(0/(^y q9. \\j'rcL^ J<jSS
ROGiCK COLLECTIOW
MORPHOLOGICAL MD SYSTEMATIC
STUDIES
ON THE
CHEILOSTOMATOUS BKYOZOA
BY
G. M. R. LEVINSEN
WITH 27 LITHOGRAPHIC PLATES AND 6 FIGURES IN THE TEXT
PUBLISHED AT THE COST OF THE CARLSBERG FUND
V.OC'
TO BE OBTAINED FROM
»NATIONALE FORFATTERES FORLAG*
COPENHAGEN
PRINTED BY FR. BAOOB 1909
(Price 45 Kr, = 50 /-)
CHEILOSTOMATOUS BRYOZOA
MORPHOLOGICAL AND SYSTEMATIC
STUDIES
ON THE
CHEILOSTOMATOUS BEYOZOA
BY
G. M. H. LEYINSEN
WITH 27 LITHOGRAPHIC PLATES AND 6 FIGURES IN THE TEXT
PUBLISHED AT THE COST OF THE CARLSBERG FUND
TO BE OBTAINED FROM
» NATION ALE FORFATTERES FORLAG«
COPENHAGEN
PRINTED BY FR. BAGGE 1909
bsloJ
TABLE OF CONTENTS
Page
Preface I— III
Terminology V— VII
Morphological Part 1—87
Calcification 1—7
Cryptocyst and Gyninocyst 7 — 8
Spines 9—10
The Morphology of the Zorecium . . 10—22
Rosette-Plates and Pores 22—32
The Compensation-Sac 32—33
Vestibulum 33—37
The 0"perculum 37—46
Polymorphism in the Bryozoa Ki — 49
Ooecia 49—67
The systematic characters in the
Cheilostomatoiis Bryozoa 67—87
The occurrence of one or several forms
of individuals in the colony 71 — 73
The Hcterozotecia 73 — 75
Anatomical characters 75 — 76
Calcification 76—77
The frontal wall 77
The pores ^. . . 77
The spines 78—79
Tlie primary aperture 79 — 84
The peristome 84 — 85
The operculum 85 — 86
The rosette-plates 86 — 87
Synopsis of the Families and Genera 88—90
Systematic Part 88
Order Cheilostomata 88
Suborder Anasca 88
1st Division: Malacostega 88
Page Family Acteidae 92—93
— Bicellariidae 93—116
— Farciminariidae 116—122
— Flustridae 122—130
— Scrupocellariidae 130—143
— Mem))raniporidae 143—156
— Cribrilinidae 156—161
2nd Division: Coilostega 161
Family Microporidae 161—166
Group Tidiifera
Family Steganoporellidae I(i7— 170
— Aspidostomidae 171 — 175
— Thalamoporellidae 176 — 196
— Setosellidae 196
— Chlidoniidae 196-201
— Alysidiidae 201—207
3rd Division: Pseudostega 206
Family Membranicellariidae 207
— Cellulariidae 209—213
Suborder 'Ascophora 213
Family Catenariidae 213—259
— Onchoporidae 259—264
— Euthyroidae 264—266
— Crepidacanthidae 266—269
— Euthyridae 269-273
— Savignyellidae 273-274
— nipi)othoidae 274-281
— Adeonidae 282-289
— Reteporidae 290-296
— Myriozoidac 296—301
— Sclerodomidae 301—304
Page
Family Tiibiicellnriidnc 304—308
— Coneschiin-lliiiidac 308—313
— Epicaulidiidac 313
— Lekythoporidae 313—314
— Eurystoiiiellidae 314
— Escharcllidai' 314—335
— Sniillinidac 335—345
— Celleporidae 345-347
Page Family Holoporcllidac 347—350
- Pctraliidae 350-353
— HipiJopodinidae 353 — 355
Literature 357—364
Explanation of the Plates 366—418
Index 419—427
Errata and remarks 429—431
PREFACE
THE studies embodied in this work were begun by me in the year KS96, after I had completed an essay on the Bripzoa in the Danish challv-formation, which received the palreontological prize offered by the Royal Danish Society of Sciences. During my investigations on the fossil species I obtained a strong im- pression of the imperfect condition of the classification of the Bryozoa, as I was frequently in doubt as to which genus or family I should refer a given species to, and I became convinced of the necessity of making more detailed studies on the recent Bryozoa before thinking of publishing a work on the numerous Bryozoa from the Danish Chalk. I did not imagine, however, that this work would take such a long time.
In this work, which deals with the most difficult ^ and at the present time most numerous of the three orders of the Bryozoa, the Cheilostomata, I have made an endeavour to reform the classification, and as basis for such a reform I have first of all made a comparative study of the structural features of most import- ance in systematic regard. I have included all the families and most of the genera of which I have been able to examine material and which I might consider as well-founded. With regard to the species I have not followed the same procedure everywhere; in the case of some families and genera I have been content to name a number of the s|)ecies belonging to them, whilst in other cases I have described more or fewer, partly new, partly older but not sufficiently investigated, inter- esting species. Of the interesting genus Thalamoporella I have described all the species I have had the opportunity to examine. The [irocedurc I have followed in the individual cases has in part been determined by my material; but I may
' "Our real perplexities commence when we attempt to frame the families and genera; for in the case of the Polyzoa it is extremely difficult to seize the significant characters. This remark applies especially to the Cheilostomata. « Th. Ilincks: British Marine Polyzoa, Introduction, pag. CX.WII.
II
add Ihal Ihe reason why there is only a small ninnher of descriptions of species in the latter part of the work is, that I desired to come to an end with a work, which has already laid a heavy toll on too many years of my life.
As will be seen, I have been obliged to make great clianges with regard to the delimitation of most families and genera, and if I have not been able to refer a larger nnmber of the earlier described species to my genera, the reason is that I have only had opportunity to examine a small number of these species and the descriptions and figures publislied in many cases do not give sufficient infor- mation regarding their structure. I hope, therefore, that this work will lead to renewed investigation of the numerous species, which are j)reserved in museums and private collections, and which have not been examined since they were described.
The first Plates to this work were prepared in the year 1901, which will ex- plain why a number of the generic names used on the Plates have later been replaced by others on the accompanying explanations, hi some cases, namely, I have often been obliged to name the figures given on a Plate at a period when I was not yet certain to what genus a given species should be referred, and I have therefore been obliged provisionally to use the earlier given generic name; in other cases I have later been obliged to use another generic name, because it had been shown in the interval that an older had the priority. In many cases I have followed the view of the priority question expressed by the Rev. A. M. Norman in his »Notes on the Natural History of East Finmark Polyzoa«. In some few cases it has also been necessary to alter the specific name.
As the Danish coasts are extremely poor in Rrijozoa, I have made several endeavours to obtain material from foreign countries which had been i)reserved in such a manner, that it was suited to the investigation of the nature of the calcification process and of the structure of the oa^cia; but as these endeavours have led to no result I have been obliged to give up my attempt at solving the first question, and with regard to the structure of the ooecia I have been unable as a rule to give information on the internal membranous parts. I have used the microtome for these investigations in a number of cases; but the spirit ma- terial employed was too old to show what I wished to see.
That I have been able to include so many forms within the scope of my in- vestigations is due for a great part to the help a number of colleagues in foreign countries have given me, and first and foremost my work will bear witness of my great indebtedness to Miss C. Jelly, the author of »A synonymic Catalogue of the Recent Marine Bryozoas to whom the Zoological Museum of Copenhagen owes the possession of so many interesting Australian and South African species. Mr.
Ill
R. Kirkpatrick (British Museum) and Dr. S. Harmer (earlier Caml)ridge, now Keeper ol" British Museum) have with great liberality and unfailing willingness lent me material from the collections in their charge, and a similar interest has been shown in my work by Canon A. M. Norman, Mr. A. W. Waters and the late Mr. C. N. Peal, to whose private collections I have very often had recourse. Mr. O. Nordgaard (Trondhjem) has always willingly sent me material of the Norwegian Bryozoa and my thanks are also due to Mr. F. Canu, Versailles, Mr. J. Gabriel, Abbotsford, Victoria, Prof. Dr. H. Theel, Stockholm, Mr. J. F. Whiteaves, Ottawa, Canada and Mrs. H. Eden (nee Gatty) for assistance with material or loan of spec- imens.
Lastly, I would express my warmest thanks to the Directors of the Carlsberg Fund, who have voted me the means not only for the continuation of my many years' studies but also for the publication of this work.
TERMINOLOGY
Bryozoid. The common name for all the individuals of a colony.
Zooecium (- autozooeciutn). A chamber in which a polypide is or has been lodged.
Heterozooeclum. A chamber in which there is no polypide or only a vestige of one in the form of a small cellular body. On the other hand the chamber contains a powerful muscular apparatus for the movement of the operculum, which in the avicularium is called the ))mandible« and in the vibraculum the wflagelluma.
Kenozocecium. A chamber in which there is no polypide and as a rule no muscles and no aperture.
Gonozooecium. A modified zooecium set apart for reproductive functions.
Polypide. The alimentary canal with tentacles etc., belonging to a zooecium.
Gymnocyst. A calcified pari of a Bryozoid which arises by the transformation of a covering membrane.
Cryptocyst. A calcified part of a Bryozoid which arises within a covering membrane. A cryptocyst arising from the vertical walls may be called a »priniary(( cryptocyst and that arising from a frontal gymnocyst a ))secondary« cryptocyst.
Ectocyst. A cuticle secreted by a covering membrane.
Epitheca. A membrane covering a calcified surface.
Rosette-plate (— communication-plate). A diaphragm, pierced by one or more exceed- ingly line pores, occurring in the walls of adjacent Bryozoids. Through these pores pass fine branches of a tissue (the endosarc or the mesenchymatous tissue) which maintains the coinnuinication between all the members of the colony.
Pore-chamber. A small space situated in the boundarj* between two walls of a zoa'ciuin, the inner part of which is provided with one or more rosette-plates.
Pores. Most of the so-called pores are not real pores, but only uncalcified (membran- ous) spots in dilfercnt calcareous surfaces. In the present work such uncalcilied spots arc sometimes (e. g. in the Catenariidae) called »excisions«, )>perforations«, i>lissurcs« or >ifenestrEe«, and the last signification is as a rule used about unusually large and regularly arranged pores. Real pores are found in the rosette-plates, in the frontal shield of the Cribrilinidae and in the peristome of Haswcllia, Adconella elc. Uncalcified spots in calci- fied surfaces may be called wpseudoporesw.
Ascopore. A pore leading into the compensation-sac.
VI
Marginal (or oral) spines. S])iiu's issiiiiif^ i'roni llic iniuT niarfiin of a f^yiiinocyst. In viTv rare cases fCri'piddcantlia Poissoni, Mcudporu hyulinaj they are found together with a strongly ik-vcloiu'd frontal cryptoeysl.
Acropetalous spines. Spines issuing from Ihe cirtunilVrence ol a pore (pseucloporu).
Bilaminate spines. Spines (generally Hat) the inner layer of which is formed by a cryptocyst while the outer layer is formed l)y a gymnocysl. They are only found in the family Cnlcimriidae and reach their greatest development in the genus Coslicclla.
Lateral chambers. Bryozoids generally developed as kenozooecia, found as a rule in a number of four on each side of an internode in the family Calcnariitlae.
Simple operculum. A wcll-chitinized or calcified separable operculum the hing-line of wMch stretches between the two proximal corners and as a rule coincides with the proximal edge of the aperture.
Compound operculum. A well-chitinized separable operculum, the hinge-line of which is placed distally to the proximal edge. Only the distal part of it corresponds to an oper- cular valve or a simple operculum. In the Ascophora the proximal part of it, the »accesso- rial part«, serves as operculum to the compensation-sac.
Peristome. A calcareous projection more or less completely surrounding the aper- ture of the zooecium. The entrance to this, often tubular, |)rojeclion is the "secondary aperturcK.
Ooecium (= ovicell). A more or less calcified marsupium placed near the zoa?cial aperture, into which the eggs pass from the zottcium in order to be develo])ed into larva.
Endozooecial ooecia. Internal ooecia consisting of an endooa'cium formed by the distal wall and of an cctoo(ecium formed by the covering membrane.
Hyperstomial ocecia. External two-layered ooecia, consisting of an cndoocecium and a more or less developed ectoooecium.
Perlstomial ooecia. Single-layered oa'cia formed by the peristome. They are found in the families Tubucellariidae and Lckylhoporidac and perhaps also the oojcia of the families Conescliarcttinidae anil Holoporellidae may be referred to this division.
Endotoichal ooecia. Hollows formed by resorption in a thick calcareous frontal wall and at last opening outwards. They are found in the families Cellulariidac, Membranicella- riidac and Setosellidae.
Acanthostegous ooecia. Marsupial spaces lying between the covering membrane and two series of concurrent spines. They are found in Electro zostericola and El. (Heterocecium) amplectens.
Double-valved ooecia. Oa?cia consisting of two arched hollow valves (kenozooecia). They are found in Algsidium parasiticum.
Basal mark. A curve seen on the basal surface of a hy|)erstomial ofecium, circum- scribing that part of the frontal wall of the zoa'cium, which takes jiart in the formation of the endoocEcium's basal wall.
Basal. The surface with which an incrusting colony is fixed and the corresponding surface in a freely growing colony.
Frontal. The surface opposite to the basal and that in which as a rule the aperture is placed. Sometimes, however, the aperture may be terminal, viz., ))laced in the ti]) of Ihe zooecium.
VII
Distal. The part of a zooecium most remote from the primary zocreium (the ancestrula) of the eolony. When used ahout the single parts of a zocreium, for instanee the s])ines, it signifies the part most remote from tlie point or the surface of fixation. —
Proximal. The part of a zoceeiuni nearest to the primary zoceeiuni of the colony. While in most Cheilostomata tlie zoa'cia have separate lateral walls the terminal walls arc as a rule common to two successive zoa'cia in the same longitudinal row and there- fore the distal wall of the proximal zoax'ium is at the same time the proximal wall of the distal zoa'cium. Only in very few cases is there found separate terminal walls (see pag. 11).
Morphological Part.
Calcification.
Different views. Different modes of calcification.
IN his well-known paper on Meinbranipora membranacea H. Nitsche' expresses the view that calcification proceeds in the cuticle given off by the cells of the covering membrane, which at the places where such deposition takes place is divided into three layers and it is the middle layer characterized by its highly refracting power which is impregnated by the calcium salts. Nitsche arrived at this result exclusively from an investigation of the not yet calcified short spines, of which in this species one occurs at each of the posterior corners of the zocecium. According to Nitsche these spines are covered externally by a thick cuticle and beneath this there is a highly refracting layer intended for calcification but which does not (juite reach out to the tip of the spine. Internally the whole cavity of the spine is covered by an exceedingly thin membrane, which according to Nitsche is the innermost layer of the cuticle, whilst he calls a net-work of cellular strings in the inner cavity the endocyst. On this view however there would be no continuous covering of endocyst in the interior of the spine, which does not seem very probable and it would therefore be most natural to call the thin, innermost layer of the wall as the endocyst and the cellular net-work as a portion of this endocyst, which has been designated the endosarc or the mesen- chyme. I have not had the opportunity to investigate an uncalcified spine of Meinbr. membranacea, but if Nitsche's theory of the calcification is correct the spines when completety calcified must be covered with a cuticle. I have sought for this in vain however, both on the spines mentioned and on all other spines examined by me and I must therefore contest the correctness of Nitsche's view^ that the lime particles are deposited in a middle layer of the cuticle.
' 80. pp. 42, 76.
In a preliminary note' Ostroumoff makes some remarks on the calcareous skeleton in the liriiozoa and comes to a totally dillerent result from N'itsche with regard to its formation. He has hecn able to siiow, namely, by lueans of silver impregnation, that the covering membrane of the zoocia has a distiiiclly cellular structure, over which he found a thin cuticle and under it the calcareous skeleton. He concludes from this that the chalk particles arc deposited within the ectoderm cells (»par consequence les particles calcaires se deposent dans I'interieur de cellules ectodermlques«). At another place he stales:- »Le squeletle calcaire de nos Hryozoaires se place parmi les cellules de I'exoderme. Le dernier exisle pendant toute la vie de I'animal on comme couche sous-squeletaire (MenibraiiijioraJ ou comme deux couches enlre lesquelles se trouve le s([uelette (LepraliaJ'.
Later in the main work' which deals with the Brijozou from the Bay of Se- bastopol, the writer expresses his oj)inion about the same subject in this way: >in the family Escharidae (such as for instance in Lepralia) the calcareous skeleton during its formation divides the ectoderm into two layers, an exterior lying over the skeleton, and which is readily seen on the opercular wall on living individuals as well as on those treated with silver nitrate, and an interior under the skeleton which can only be seen by means of silver impreg- nation. There is only one layer of cells in Memhraniporidue, and this is only found below the skeleton «.
Ostroumoff's observations are based on the small number of species which are found in the Gulf of Sebastopol, and Lepralia PalUisiana is the only representative of the sj)ccies of Escharidae which he has been able to examine; it belongs to the forms which develop a calcareous layer, the Cryptocyst, under the covering membrane of the frontal surface, but separated from this by an intermediate space, and having a cellular lining on both its surfaces. This is however not an absolute proof that calcification has taken place within the cells, so that Ostroumoff has just as little as Nitsche proved the correctness of his view. I'ergens expresses a view similar to that of the Russian writer, partly in a small prelimi- nary paper: ^ (»bei alien Arten, welche ich untersuchte, war von aus.sen immer die Cuticula und der Kalk innerhalb der Zelle gelagert«). partly in a paper concer- ning fossil Brijozoa'', where he says: »Le derme est essentiellement constilue par un nombre variable de cellules aplalies a contour irregulier^ (Ostroumoff). Mes observations sur les larves (jui viennent de se fixer m'ont demontre cpie c'est dans I'interieur de ces cellules cjue se fait le dej)6t de calcaire . In contrast
' K8, p. 291; ' 89, p. 577; " 90, pp. .J8, J9 ; * 92, p. .'iOG; ' 93, p. :t08.
lo llu' two lasl iiu'iitioncd writers, Calvct andHaiiner look upon calcificalioii as a cuticiilai rormalion, but while Ca 1 v e l' tliinks that calcification at any rate in the CheUostomata takes place through the whole thickness of the cuticle, the following ohservalioii of Harmer- seems to suggest that he is inclined to share Nitsche's view of the calciiication as j)roceecling in the central part of the cuticle: in incinerated specimens the lateral walls of neighbouring zoa-cia may appear separated from one another by a narrow slit in jjlace of the laised linc<'. This is in fact the edge of a chitinous layer separating contiguous zoa-cia, and prolonged into the membranous epitheca. This agrees with the account given by Nitscbe of the calciiication of the zcxj'cia of Mcinbrdiiipord membi<uuict'<t, in which calcareous matter is said to be formed in the middle of the chitinous ectocyst, part of which is left on each side of it«. We shall return later to this statement. As I have not been able to examine living material I do not consider myself qualified definitely to decide which of the views is the right one, still it seems to me that the »cell-theory« is the one which explains the different plie- nomenona, which the calcification presents, in the easiest and most natural way, and it seems to me especially difficult to explain the presence of such solid sjjinous processes on the outer surface in a number of species (e. g. in llolo- porelld columnaris) as well as on the inner (e. g. in Menipea roborala Hincks and M. lifiiilata Mac Gill.) by the aid of the cuticular theory.
We may now consider a number of differences which the calcification pre- sents, and to begin with we may distinguish between more or less compact or firm calcifications. The very dilTerent resistance which the calcified skeleton is able to offer against breaking and grinding shows sulTicienlly Ihat the comj)aclncss and firm- ness can be difierent, and the firmest skeleton is undoubtedly found in the families of Sclerodomulae and Releporidae just as we find the weakest in the families Bicella- riidae, Flustriilae, Onchoporidae and in certain species of Membntiiijidrd. U we regard parts of the skeleton of certain, very slightly calcified species (e. g. of Meinbranipora membranaced, Electra pilosd, Flustra Cdrbdsea, Dendrobeania miirrdi]- ana and Oinliopora Siinldiri) under a raliier liigh magnification, it shows a grained or dotted appearance, but under a very high power (immersion) it dis- solves into a dendritic network, the meshes of which enclose numbers of small uncalcified spots, which give a reddish light. Sometimes, liowever, the same wall may show more or less calcified parts. We thus find in Dendrobeania miirruyunu that the part of the basal wall, which touches the distal wall, is much more calcified than the other part, ami in the middle of the basal wall in Escharoides Jacksoni
' 9, pp. 29 & K;.-); * 17. p. 227.
1*
\V;ilcrs we find :i Iiir^ir (jval wliitc s|»ol svliidi is jess calcified lliaii the rest of llie J)as!il wall, luiii^ formed \)y a net-work ol iriesiies, and the wiiile colour is dm- to (lie fact thai the liglit is reflected from the numerous small surfaces of wliich this net-work is c-omposr-d. In Mi'inlimni/iorin/i arciicn, Siiiillinri Irisfjinosd, var. I'lmclhmn and Siii. iir<if)iii<iiiu Ihr; hasal wall is covered hy small snow-while, round spots of a similar structure. As to the manner in wliich the calcilication lakes place, we can distinguish hetween coin|)Ound and simjile walls, as a wall in some cases calcifies as a whole, wliile in other cases it calcifies in more or liiHH separated piec^!H, whicli at any rate u|) U> a certain period are se|)arated from one anollier hy sutures, and these sutures are in some cases very distinct lor a \itw^ liini', wliiUf in oilier casis Ihc^y disappear very (piickiy. 'I'liis concerns very ollcii llic liiiiilal sv:ill, and is due to (he circunistance that this is very often provided willi covering layers or sculpture of various kinds. As examples of sjiecies willi simple walls v,v. may meiilir)n Mcmhrtiiiif/oni iiieiiihrdiiiicen, Elcclra jiilimii, species of I he genera Oiiijiliocelln, ni/i/iolliati, riialfiiiioixirellti, and Slet/ii- iiiifinrclld and also il sr-ems — all memheis ol the families liiccllariidiic and
Si rniioiflliii iiiliif. 'I lie p.nls inio wliich a eoiii|)oiiiid wall can he divided vary very greatly in size, and llir- smallest of them give the imjuessioii, nol only from their exci-edingly small size, hut also from Iheir shape, thai they are calci- lied cells, as they have the same ci-eiiiilalerj contour whicli as a rule seems to disliiifMiisli llie eelodi Till celK in llir Hn/ozoii. 'I'liis lonii of calcilicalion, which we niiglii I'.'ill »eell mosaic is lor instance roiiiid on llie hasal wall in Mi'iiihrimi- jKini SiiiKiili, l-'liislni (Iniliiiiliild (\'\. XIX, lig. 10 v), J'otalhi cunciniui, ni/iiJOfxidiiKi fiu'iicriisis Musk, Siiiilliiia LdiiHhoroui, as well as on the laleial walls of i'luslvd si'iriildhi. (iradiially s<'veral of tlmse very sniall cellular areas fuse logelher lo larg(!r ones, and in older zoom- i a the nniik of division may (piile ilisap|ieai'. In conlrast lo Hie very {\in- mosaic we lind in Hie jusl-mentioncd species, olhei- sjx-cies pre- seiil a mosaic c(Misisliiig of iiiui-h largi-r hut sliU comparalively small areas, which caniuil very well he regarded as cells. This form of calcilication, which we nii;',lil cill plale mosaic , wi' lind \eiy linely <levelo|)ed on Hie hasal wall of I'liislid ^nnrifiDiis (\'\. XIX, lig. H a) :iiid wc may here give a detailed desci'i|)liiin of ils .ippeaiance in lliis sjX'cies, which lik(; mosi Fliislrd species has a peiiecHy nncah-ilied IVonlal wall. The coni|)osilioii of Hie dillcrenl walls can hc'.t he seen, as everywhere in Hie Hni<i:iiii, allei lliey lia\c been boiled for some linie in .'ilkali, oi li:i\c hern lic.'iled wiHi f.\ii ile .hnclle, which cvi'ii in a cohl condiHon has a lar liellei ellerl lliaii hoiling alkali. Having dissolved all organic pails willi such Irealniiiil, we lind as a rule a rcnv of scpiare or li('xagonal plates along Hie middle ol every hasal wall, while il seems as if a similar longitudinal
low ol' |)l;ili*s on cmcIi side of llic middle one liiis one half williin llie same zoo'cium, and llie olher hall' witiiin llie adjoiniiifi; zocx'cium. These apparently liall" parts do not ix'loMf^ lo each other however, as each of them j)asscs over into and joins at a rif^hl angle lo one of the small plates of which each lateral wall consists. That two adjoining rows of half plates seen from the surface of the colony can look like a row of whole plates, is due |)arlly lo the fact that they lit exactly btleach other, partly that from the surface we cannot see the halves adjoining one another in the vertical walls. Further, as the zod'cia in one layer of the colony alternate willi those in the second layer, a median row of ])lates in one layei- will corre- spond lo a donlile I'ow of adjoining half plates in the olher, and Ihe two ad- joining half plates are in size almost exactly like Ihe opposite plate. The ter- minal wall is divided into two lateral halves hy a suture, running medially through Ihe single rosetle-])lale. At the borders helween Ihe single longitiulinal rows we also lind small iincalcilied inlerspaces, while the plales in Ihe single rows are separated by narrow sutures. 1 have in Iwo previous |)apcrs ' designated this manner of calcilicalion as circular, because the calk pai'licles in Ihe individual small plales are circularly arranged round a small condensed shining spot, which we might call Ihe 'Centre of calcilication«, and which in Ihe angularly bent plates is placed in Ihe angle helween Ihe Iwo pieces of each plale. 'l"he circular arrange- menl is most distinct close to Ihe centre and vanishes gradually furlher out. Still, more or fewer zoa-cia show a less regular arrangemenl of the small plales in the marginal pari of the colony, and Ihe same can be seen in scattered zoo'cia in olher parts of Ihe colony. The basal suil'ace may Ihen either be broken up into an irregular mosaic of larger or smaller jjlates of dilTerenl sha|)e, or llie median row of plales may be missing or represented only by very few ])lates. We can even here and there lind a cell-mosaic. I have found a plate-mosaic like Ibis on Ihe lateral walls in I'liislra foliiiceii (I'l. .\l.\, lig. U b), on Ihe basal wall in I'orclld sdccdhi, I'or. roiiiiircssd, Smilliiid tiisiiiiKisa. Sni. pdUiuild (I'l. .\IX, lig. 5 b), .S';)(. liiiedris, Discopord pin'oiiclla, l-liislra sririilald, Fl. piscifoniiis as well as on Ihe front wall of liii>cisiiild iiincrsd and Anarihropord nioiiodon. In contrasl lo what occurs in /•'/. scrnrifrons none of these species show a regular arrangement of Ihe small plales, and in a nund)er of lluin (he laller appear in a very irreg- ular and variable way, as they may appear logelher willi olher forms of calci- licalion within the same colony, even on Ihe same wall. Time does not allow me lo enler inio details, bul 1 will jusi meulioii Sniillimt Irispinosd. Iliislrd scrni- Idid and /•'/. piscifiiniiis as examples of such si)ecies. While Ibe small plales in
' Til, p. •_'!(;: .').'.. |> :t.
;i mimlier of the here mentioned species show plainly concentric lines of growth, they on the other hand show a distinct radiate arrangement in Inuerxitila iiiuersd and AiKirlliropoia luoiwdnn (PI. XXIII, ligs. 10 a, 11 a). These small plates which arc only distinct in quite young zo(vcia are each i)rovided in the centre with a pore, the edge of which has radiate rods, and to judge from Hi neks' drawing the front surface in the following sjiecies descrihcd hy him is also divided into a number of small plates each of which has a pore in its centre, namely, ^Lepruli<i<, I'alUi- si(tna (from Madeira), Sc/)/ro/jorc//o cinctiporn Hincks, ^Scli.* cnnciiinn Hincks, Arlhio- pouui circiniKild Mac Gill., Lcprnl'ut siibiiuinrrsd Hincks and Lep." giyas Hincks.
In numerous species which appear in free colonies either the l)asal wall or the frontal wall or both show a mode of calcification which we might call the bilateral, as the wall in question is calcified in two lateral halves, which meet in a longitudinal suture and as a rule each lateral half seems again composed of a row of pieces the dividing sutures of which meet the longitudinal suture oblicjuely. We may cite the structure of the liasal wall in Fliislni foliacen (PI. XIX, fig. 9a) as an example of this form of cakilicalion. On this wall we find two systems of extremely fine stripes, which meet under |)roximally directed angles and divide the wall into two lateral halves, separated by a longitudinal suture; the two halves are again composed of a row of pieces, and these arc .separated l)y distally directed, slanting sutures wdiich end in the main suture. Each of these lateral pieces is further joined to one of the pieces in which the respective lateral walls are divided. We can be sure that the above-mentioned fine stripes are lines of growth by treating the growing end of a branch with eau de Ja- velle; for after this has dissolved the uncalcified parts, the basal wall of the terminal zon^cium shows an angular incision which corresponds with the angle between the two systems of stripes. This form of calcification which can also present a number of modifications is for instance found in Fliislra Barleei, Fl. niem- hritiuice<>-lriinc<tta, Fl. papyracea, Discoporii iwrriicosa, Dis. pdonnella, Dis. srabra. Siiiillii)(i propinqna (PI. XIX, fig. 3 a), .S;n. rcliciihild, Sm. palinula (on the fronlai wall), Arthroponid Cecili, etc. and no douhl it appears in most cases on the frontal wall in species furnished with marginal pores, each of which serves as the starl- ing-point for a suture which in most cases ends in the median suture. Still, a median suture may be absent in very short zoa^cia and we find instead a nund)er of fan-shaped, converging suture lines, as in Discopord pdvnneUn (PI. XIX, fig. 2 a). With exception of the walls which are provided with si)ecially small pores {ThaUimoporelld, Sleganoporella), all the surfaces (frontal walls, o(vcia), which are furnished with scattered pores, are al.so provided with numerous sutural lines, as these start from each pore, and except for those which end in the free edge of
the surface, all (he otiieis ciul eillu'r in a new pore or in another siiliirai line. In Crista ehmneii the calcification takes phice in narrow longitudinal belts, and a similar mode of calcification is seen in the short and wide hollow protuberances, which are situated on each side of the aperture in several Thalamoporella (PI. Via, figs. 4a, 5a). Besides the form of striping, which is due to lines of growth, and which for instance is often very distinct in the Hippothoa species, the basal wall especially of the zorrcia often presents a distinct, longitudinal or fan-shaped striping which is most probably due to the arrangement of the separate lime particles. This form of striping is widely distributed in the species Bicellariidce and Scrupocellariida:
Before leaving this subject I must shortly mention an apparent observation made by Nitsche', according to which the calcified frame of every zoa'cium of Meinbr. membranacea after boiling in alkali is divided into three pieces, namely, in two double-folded end pieces each consisting of a terminal partition wall and a piece of the adjoining side-wall, as also of two lateral pieces. This view is nevertheless not correct. After boiling like this more or fewer zoa-cia in a col- ony may indeed show cracks or bendings, but these are quite accidental, and not an expression for the mode of calcification of the zocecia.
Cryptocyst and Gymnocyst.
Under the generic name Omjchocelld Jullien" has described several recent species of a type which had a great extension in the seas of the chalk period but which only has a small quantity of now living representatives. As is the case in a Flustrd species, the whole of the frontal wail is covered with a mem- brane in which can be seen an opercular valve, but when we remove this mem- branous cover we find underneath it and separated from it by a distinct space a more or less concave calcareous layer, which dislally has a semicircular aper- ture (opesia) through which the polypide can make its way out. This aperture which was formerly regarded as the orifice of the zon-cium in the fossil sjjccies is consecjuently separated by a space from the real orifice, which is situated in the covering membrane, hi contrast to the membranous ectocyst Jullien designates this deeper-lying calcareous ectocysl as a Cryptocyst, and proposes on the basis of this observation to divide the cheilostomatous Rnjozoa into two divisions, accortling to the presence of a single or double ectocysl. To the first division: Monodernuda, be refers such forms as Eschani foliacea, Lepralia hijaUiui, L. coccinea, CcUeporn piimiaisd and Fltistra folidCfd, and to the other division: Diplodcrnuttd, besides
' 80, p. 42; - 42.
the species of the genus Onijchocelld, BijUislra <lclic(iliil(i, Viiiciildrid ulnjssicoUi, Steyanoporelld Smitti, etc. In a later paper' besides a number of new genera, species of the genera Acted, Microporvlld. Scriii>occlldrid, iiiccUdrid, C^hiiliiui. Ijujeni- pord. Scliizoporella, Siniitia. Mncronclld and Reicpovd are referred by liini to the Monoilernmta, while he classes species of the genera Cahered, Mcnihidnipord and Sclosclld to the Diplodennald. In a third paper however he has altered" his view of the extent of the Diplodenuata, in that he now classes some of the forms which in the earlier papers he placed under the Munoilenudtd lo the Diploder- inata, namely, all the families Encntteidde, Ccllnldriidde f= ScnqioceUdiiUtde). Hi- cellariidde, Noldiiuidae, Flustridae, Meiubrdiiiporidde, GemelUuiidae and Fdrciinind- riidae. While a systematic classilication on the basis of the structure of the frontal wall is still found in a work of Canu' from the year 1900, on the Brijozod of the Cretaceous period, this classification seems cjuite given up in a later coopera- tive work by Jullien and Calvet'*, which after the death of the first men- tioned writer has been carried on and published by the latter. Calvcl'' gives very important information about the structure of the frontal wall in a large work dealing with the structure and development of the ectoproct Brijozou. Be- sides in Eucrnted Lafonti. Membranipora Rosseli and the species of the genus, Cellaria, he has found a double ectocyst in the species examined by himself oi' the genera Tiihucellaria, Microporello, Chorizopora, Schizoporelld, Lepi(di(i, rniboiiidd, Retepord and Cellepord. consequently in forms which according to .In Hi en's examination have a single ectocyst, while he has found a single ectocyst in the examined species of the genera Aeled, Scnipocelldria, Caberea, Biiyiiki, Flustra, and in Meiubraiiipoid pilosd and Membr. Flemingi. As to those forms which have a double ectocyst, he gives the interesting information that the interspace between the membranous exterior and the calcified interior layer (the Cryptocyst) is every- where covered by epithelium, and moreover contains leucocytes and a mesen- chymalous tissue. Except in the Retepord where the basal wall of the colony also has a double ectocyst, he only finds such an ectocj'st on the frontal wall.
The result of the investigations above-mentioned is, consequently, that we can distinguish between skeletal parts which come into existence inside the covering membrane and independent of this (the Cryptocyst), and those which arise by transformation of the covering membrane. We may call these last-mentioned parts of the skeleton whose frontal surface consecjuently has no membranous lining (an »epitheca«): the »Gymnocyst«.
' 43; - 45; ^ 11 ii; Mli ; '' pp. 103—168.
Spines.
Under the name of >spines« we undersland in this work only a sorl of liollow projections of the onter snrCace of the zoo-cinm, whereas we may designale all solid projections, issuing either from the outer or the inner surface, in a diU'erenl manner, for instance as spinous processes-, »denticles« or in a similar manner, according to Ihc form and size of the projeclions in ([ucslion. Such solid spine-liUe projections are present on the outer surface for instance in HoloporelUi hastigern^ Busk, Hoi cohimnaris', in the species of Farciminaria (PI. 1, figs. 10 a— 10 c) and most species of the genus Spiralaria (PI. 1, fig. 9 c), and on the inner surface e. g. in Menipea roborata (PI. II, figs. 7d — 7 e), Hincks and Men. lignlala (P]. II, fig. 8 c) Mac Gill. From the position, structure and mode of growth we can distinguish between three different main forms, which we may call marginal spines or folded spines, acropctal spines or annular spines and bilaminale spines.
1) Marginal spinex or folded spines. While these spines may appear in larger or smaller numbers on the frontal wall of species with a membranous frontal area, in the circuit of which they are placed, they may also appear in numbers of 2 — 10 in forms where the frontal area is lacking, outside the anter of the aperture. All these spines originate, as Harmer^ has already found in Memhrani- porella nitida and Crihrilina annuhtta, as crenulalions or folds of the gymnocyst margin, which surrounds the membranous frontal area (PI. IV, figs. 2 a — 2 c) or the anter of the aperture, and the two lateral halves of the fold grow finally to- gether in a longitudinal suture which is turned towards the zoa'cium, and which can often be seen for a long lime even after the spine, by continued growth at the point, has reached its full length. As the fold is closed it comes to enclose a part of the frontal area, and the growing spine will constantly be finished off by a membrane, which is the condition for its further growth in length, and which only disappears when the point of the spine calcifies. These niai'ginal spines, which are always foriued by a Gymnocyst, present a certain likeness in their mode of formation to, the hollow outgrowths of the rim which a])])ear in various snails, for instance in Pterocera chiragra.
2) Acropetal spines or annular spines. These spines which are only found in a small number of Brgozoa. begin as a ring-shaped growlh on the circum- ference of a rounded uncalcified part of a surface, and grow in other respects in the same way as the marginal spines by means of a membrane at their free end. To these belong the (as a rule) unpaired spine which is situated at the end of the membranous frontal area in the genus Electrn, the unpaired spine in
' 8, p. 192; - 8. p. 1!)4; ' 19, p. 292.
10
Escliarina spiiiifera, the two laii^e distal projections which a[)peai- in a number of species of the genus Thalamoporella (PI. Via, ligs. 4 a, 5 a) and llie two corre- sponding projections in the genus Claviporella (Pi. XX, fig. 10 a). Undoubtedly also, the very long and thin spines which appear at the edge of the calcified, arched fronlal wall of ^Lepralici< Poissoni in a very unusual way, belong to this division, and also the likewise long and thin spines which somewhat scattered and in great numbers surround the anter of the ajierture in Scliizofxirclla hiscridlis Hiucks ', and which give the impression of having been formed lound a number of the nume- rous scattered pores which appear in this species, in the same way as the very short arched projections which occasionalh' appear round ocrcial pores, for in- stance, in the species of the genus VJaviporelln. The hue acrojielal spines like the marginal ones are always formed by a Gymnocyst, but in PordUt (?) corniita (PI. XVIII, fig. () a) the endoooecium in a numJ)er of zoa^cia is furnished with one or more hollow spine-like processes which in the same manner as the acropetal spines have a ring-like origin and are no doubt formed by chalk-particles depos- ited under the membranous ectooa>cium. These projections, however, are in no inner connection with the ooecium and cannot therefore be looked ujion as true spines.
3) The bildininale spines, which have hitherto only been found in the family Catenariidce and will be more fully spoken of under this family, spring from the free margin of a moie or less developed sinus (Ihc sternal sinus), from the margin of which also an inner Cryptocyst lamina takes its origin. As these spines issue from a margin in which a Gymnocysl and a C-ryjitocyst meel, they must of course be two-layered, their outer layer l)eing formed by the Gymnocyst and the inner by the Cryptocyst. They attain their highest development in the genus Costicella (PI. XII, figs. 1 a— 1 d, PI. XX, figs. 8 a— 8 b, fig. 9 a).
The morphology of the zooecium.
As is known we can in the cheilostomatous Bryozoa distinguish between six, as a rule well-separated, walls, namely, the two lateral, the two terminal, the basal and the frontal. It is generally difficult however to distinguish exnclly between the lateral walls and the fionlal wall (or basal wall) in species which appear in single rows, and in those zoci'cia which arise by superficial gemmation and in most cases in moie or less erect {josilioii (I'or instance in the ('.cltcpord and Iloloporclld s])ecies) only llie basal wall is sliar|)ly hounded, the other walls
' 3U, p. 250.
11
riimiiiig into each other. It would he most natural only to count the adjacent jiarts of two neighhouring zooecia as lateral walls, and to regard the whole frontal surface of the zofX'cium as the frontal wall, even if the lateral parts of it are sometimes almost vertically ascending.
In contrast to what takes place in the Cyclostomata, in which all partition walls are single and common for two adjoining zoa-cia, the lateral walls in most of the Cheilostomatd arc independent, and after treatment for some time in eau de Javelle or with hoiling alkali, most of the colonies can be broken up into a number of longitudinal rows of zooecia. Still from this rule maj' be excepted a number of families and genera, as Cellulariidce, Cateiuiriidcc. Myriozoidce, Sclero- domidcv, Tubucelloriidcv, Cniiescharelliiiidcv, SeleiKiria and Lunidites, and even within genera, the species in which have independent lateral walls, for instance Porella, we can find species e. g. P. saccata, P. compressa and P. tnbidifera, in which the lateral walls are common to two zocrcia. Such common lateral walls seem ex- clusively to appear in free growing species, while on the other hand several species with free growth have independent lateral walls, e. g. the members of the families Scriipocellariida' and Bicellariiila'. The same is the case with the free-growing species of Steganoporella and TImlainoporella. If we make a section through a decalcified colony of one or other s|)ecies which has indepen- dent lateral walls, e. g. Steganoporelht mcKjnilabris, we see plainly that there is no membrane between two adjoining lateral walls, but that each of these is in direct communication with and passes over into the frontal membrane of the corre- sj)onding zocpcium. The reason why the two lateral walls are separated by the above-mentioned treatment may be that the fluid dissolves a part of the organic matter which the walls contain, and that these then draw themselves together in a similar way as a piece of wood does when it dries up. With this also agrees that such a separation of adjoining walls takes place much easier in younger zooecia than in older, in which the calcification is more advanced.
As a rule the terminal , walls in contrast to the lateral are common to two zosecia lying behind each other and there are only a few exceptions from this rule. One is presented by the species of the above-mentioned genus OmjchocdUi (PI. XXII, figs. 3a — 3d, in which this wall can also be split into two after treatment with eau de Javelle, so that we might here speak about a separate distal and proximal wall. As the genus Omjchocella commences in the Jurassic and has its widest extension in the Cretaceous period, we very likely have to do with a primitive condition. Separate terminal walls "also exist in the kenozoocia of Rete- pnra tcssellala (PI. XXIll, fig. 1 a) and lid. lata (PI. XXIII, figs. 2 a— 2 c), and
12
Memhraniponi Xornidiu n. sp. (PI. XXII, fif^s. 5 a — r> c) is also a partial i-xccplion to the above rule, as the ohliqiiely ascending frontal i)art of the terminal wall can he s|)lil into two, which on the other hand does not seem to he the case with the horizontal pari of this wall.
Of the tw-o other walls we may first consider the frontal (or oral), which presents the most nnmerous modifications and is therefore systematically the most im])()rtant. In a preliminary paper' I have proposed to divide the cheilostom- alous linjozod into four groups: Mithicoxlecja, Acanlhoslcgit, (]oU\xlv(jii and Cjiumro- steya, which are to a larger or smaller degree based on the structure of this wall. Of these the first three correspond with the division instituted in this work under the name Anasca, which covers all the chcilostomatous linjozoa with no com|)ensation sac, while the fourth corresponds to the Asi-ojtlioni piovided with such a sac. Though I only intend to keej) two of these names for systematic divisions, it would be practical to use adjectives corresponding to all the four names, in order through them to indicate essential dill'erences in the structure of the frontal wall. This may namely be rej)resenfed only by a membrane (mala- costegous Cheilostomat(i) in a largei- or smaller ])art ol' its extent, or is (|uite cal- cified (stereostegous Ch.). In the latter case the chalk cover may be arched (ca- marostegous Ch), or it may be depressed and encircled by projecting margins (coilo- stegous) Ch.). Finally, above the covering membrane there may be a chalk co\er consisting of two rows of hollow spines connected with each other in dill'ercnl ways (acanthostegous ^.Vi.), and lastly, we may just recall tliat the calcareous skel- eton itself may either be a Gymnocyst, a Cryi)locyst or a compound of both.
Before we try to give a view over the ap|)earance and extension of the Gym- nocyst and the Cryptocyst within the dilferent families of the cheilostomatous Krijozoa, we may discuss some criteria, which might lielj) to determine the ])res- ence of these two kinds of skeleton in cases where there is no possibility of deciding the question directly, namely, by observation of the membrane which should always cover the Cryptocyst. This ap])lies not only in most cases to the dried liryozod, but the thin membrane is also torn away from many colonies pre- served in spirit, and I may mention as an instance, that I have had to examine many spirit specimens of Iisclt(iioi(hs .hich'soni before finding the covering mem- brane. The lateral and oral spines always, as mentioned before, spring from the border of a Gynmocyst, and therefore we can with certainty take it for granted that every calcification which appears within such a spine-bearing border or from a corresponding border in a non-spinous s])ecies is a (Cryptocyst. Ilarmer'-
' 56, p. 2; - lU, p. ;i2G.
13
concludes rightly therefore in saying that the calcification, which ajjpears within the marginal spines in the primary zoircinm of Schizoporella uuUjarh, is a Cryp- tocyst, and such is found at the same place in many malacostegous Cheilostomala. A Cryi)locyst of this sort is not only very plainly hollow or depressed, which is in contrast to the arched Gymnocyst, hut also varies as a rule from the latter by having a more or less grained or rugged surface.
We can find all sorts of transitions hetween a completely membranous and completely calcified frontal wall among the forms without a compensation sac, and for which we have suggested the name: Auasca. The whole calcified part is sometimes a Gymnocyst, sometimes a Cryptocyst and sometimes, both kinds of calcification may appear at the same time, the Cryptocyst s])ringing from the Gj'ninocyst where the latter passes over into the membranous area. We can dis- tinguish between a distal part, a [)roximal part and two lateral [)arts for the Gymnocyst as well as for the Cryptocyst. The distal ])art is in most cases the least developed because of the position of the aperture in the distal part of the zoo'cium, and may in the Cryptocyst not seldom be (juite missing, while the proximal part as a rule has the largest extension. A peculiar excejjtion is found in the form which Busk describes as Diaclioris magellanicd, i>. (Iistans\ but which must undoubtedl}' be regarded as an independent species. The proximal part is here very feebly develoi)ed, whilst the two lateral regions are verj' broad and only separated by a split in the middle line of the zoo'cium. hi very few cases, as in Membranipora delicatiila, the proximal part may grow out as a tree lamina which is not connected with the lateral regions, and when such a lamina again meets these (listally we have the peculiar condition known in Calesclutra denlknlala, in which the frontal wall is furnished with two long and narrow fissures. The distal part may in some avicularia, for instance in the lyre-shaped forms, exceed in extent the proximal (PI. Via, fig. la, 2a, 3a). While a Gymnocyst in the Flus- tridue is either (juitc lacking or only rej)resented by a faint marginal part, there can in a number of species, as e. g. 7*7. denticulatci, Fl. ccirbacea, Fl. serrii- lata, Fl. biseriula, Fl. cribriformis and Fl. Schenaiii, n. sp., appear a feeble, more or less knotted Cryptocyst, the proximal |)art of which is most developed. While the Cryptocyst appears very late in Fl. dei)liculata and therefore can only be found in older ])arts of the colony, we find it very early developed in Fl. serru- lala and Fl. carhasea, in which species it is only lacking in the very youngest zooecia. Longitudinal and Iransverse sections through such a colony (PI. XXI, fig. 10 a — 12 a) show that this Cryptocyst, which Waters'- calls the chitino-
' 8. p. .'ji); ■■' 109, p. 28(1.
14
calcareous band in Fl hiseriatu. begins a little l)el()\v tbe up])er edge ni" llie ver- tical wall of the zotrcia. This Cryptocysl reaches a somewhat greater develop- ment in Fl. cribriformis and /•"/. Schaiund (PI. 1, fig. 7 a, 7 c), in which it shows a varying number of lines of growth, according lo the age of tlu' zoo-ciuin. W'e may mention finally, that while the zotrcia in the free pari of Fl. [oliacea have no Cryptocyst, such is rather highly developed in the incrusling part of the coi- lony and al.so, that it is well-develoi)ed in the avicularia of this s])ecits.
Of the forms which we have here classed to the i'ainily l-'nrciiiiiiKiriidnc, the fiontal wall of most of them has neither a Gymnocyst nor a Cryptocyst, or there is only a faint trace of the last. On the other hand both of them appear rathei' well-developed in Fdrciininaria appendicnlala (PI. 1, fig. 11) and in Xcllid Icnella (Pi. 1, fig. 1^). Within tlie family Bicellariidae we find a completely membranous frontal wall in most of the species referred to the genera Ihiskia, lieaniu and Diachoris. The Gymnocyst reaches its greatest development in Dintclopia and Hicellarui, because it may here attain more than half the length of the zoct'cium (PI. IV, fig. 5 and 8), while it only has a small extension in most of the Bugiilu species. With excep- tion of Bicellaria grandis (PI. IV, fig. 5 a), in which species we find a large distally freely projecting Cryptocyst lamina, I have not been able to find any trace of a Cryptocy.st in any other Bicellaria; still it seems as if a slightly developed Cryp- tocyst can be found in almost all other members of the family, at least in the older zott'cia, in which it often seems to be represented by the proximal part, which shows distinct lines of growth. The whole of the Cryptocyst shows distinct lines of growth in the figure of the zoa'cium of Maplcsloiiia simiilc.v shown in PI. IV, fig. 9 a, but the proximal part is only slightly developed. With exception of the Flustra-Vike Hoplilella armata (PI. II, fig. 10 a), in which the whole of the frontal wall is membranous, a larger or smaller part of this wall is calcified in the rest of the members of the family Scnipocellariidcc, and they have as rule a Gymnocyst as well as a rugged or grained Cryptocyst, which in Cellularia ornala even seems to form the whole of the calcified i)arl of the frontal wall. The Gymnocyst however forms most fre(|uently the major part of this wall, and its proximal part in Menipea acideala and Men. clau.sa attains nearly the two-thirds of the length of the zoa-cium. The Cryptocyst seems to he strongly developed in most of the Caberea species. While the whole calcified part of the zoa>ciimi in the Aeteidac is formed by a Gymnocj'st, the conditions are very variable within the large family Mi'inbrani- poridae. While the whole frontal wall is formed by membrane in Meinbranipora nieinbranaceu and related species, a larger or smaller part of it is calcified in most of the remaining forms, and this calcification is sometimes represented only by a Gymnocyst, sometimes only by a Oyptocyst and sometimes by both.
15
In tlie species belonging to (he genus Electra (E. pHosa, K. vcrticHUila, E. bellnUi etc.) we find a good-sized Gymnocyst, and the Cryptocyst is either (}iiite lacking or is represented only by a veiy slight margin within the spines. In the genus Cullo- pora a cryptocyst is developed in \ery varying degree and in C. lineuia, C. cra- ticiild, C Diiinerili and C aiirila it is represented only by a slight granular margin in the circumference of the membranous area, while in other species as e. g. in C. Flemiu(ji and C. trifoliiim it has grown to such an extent that the zod'cium lias only a little trifoliate aperture. Hi neks calls it in such s|)ecies »an inner lamina«. Finally, the calcified part of the frontal wall in Mcnib. (irc- tica, M. Rosseli, M. cornigerd etc. is only I'oimed by a Cryptocyst, as is also the case in the species referred to the genera Oiujchocella and Chaperia.
The Gymnocyst may attain a very different degree of development in the forms of the family Cribrilinidae, and its development is naturally in inverse proportion to the extent of the characteristic area, which consists of two rows of mu- tually connected spines. While this area in some forms, e. g. Membraniporella nitida and Cribriliiia annuhitn, constitutes the whole or almost the whole of the frontal wall, a smaller or larger part of the latter is in other species formed by the true Gym- nocyst. Cribrilina Gattya- and Cr. chlitridiata among recent forms are perhaps those in which the Gymnocyst reaches its largest relative development, and its proximal |)art may here sometimes reach the same length as the area. The area is of still smaller extent, and almost to be regarded as rudimentaiy in some species from the Danish cretaceous formation. A Cryptocyst seems to appear, within this division, only in species of Membrani-porella as a narrow niarginal region round the menil)ranous area of the aperture.
In the forms which we have called >coilostegous«, namely, in the members of the families Chlidoniidae, Ahjsidiidae, Cellulariidae, Microporidae, SleyanoporeUidae and ThalamoporelUdae, the frontal wall is formed by a depressed Cryptocyst, but in the last of these families the two marginal regions, which hound the opening distally and which often end in arched protuberances, are formed by a Gymnocyst and as a rule sej)arated from the Cryptocyst by a well-marked boundary line.
The numerous families belonging to the division of Ascophora all have an arched calcified frontal wall, and as previously noted JuUien refers the repre- sentatives of this division, mentioned by him, to the Monndcrimda, by which he understands those forms which have no Cryptocyst. Calvet' however, for a number of these forms has proved that the arched calcified frontal wall is in reality a Cryptocyst, and according to my investigations this is the case with
■ 9, p. 16(i.
16
most ol' the families in this division; still I have not l)epn ahle to find a cover- ring menihrane in members of the families Calenariidde, Uii)pothoida\ Eunj- stoniellidae and Eulhyridoe, nor in the genera Iiwersinla and AiKirlhrojiora, and I must tlierefore ascribe a Gyninocyst to all these forms.
The two divisions M(d(icnslc(ia and Cniloslt'tja in reality evenly grade into one another, and there is no doubt that the coilostegous forms have arisen from the malacostegous by the extension of the calcification all over the frontal wall. In some Tluddinoporella species, for instance in Th. e.vpansti (PI. VI b, fig. 5 a), the operculum is surrounded by a completely calcified frame-work, while in most of the species it is connected \vith a small membranous area posteriorly. We find a sim- ilar relation between the species of the extinct genus Rli(i<iasostoma and the species of OnychoceUo, between CcllnUtria and MeinbvankelktiUt and between Micro- pora and such Memhranipora species as Memb. argentea Mac Gill.', in which the membranous area is only represented by an exceedingly small part proximally to the aperture. The close connection between the Membraniporidac and the forms now classed under Micropora, TbalamoporeUa and Sleganoporella, seems never to have been doubted, and therefore older writers, such as Busk, simply refer such sj)ecies to the genus Membranipoiit. Hi neks'" speaks about the relation between the Meinbruniporidae and Microporidae in the following way: »In the most typical forms, such as M. inembraiuicea and .1/. Lacroixi, the entire area of the zore-cium is covered uniformly l)y a membrane, which lies a little below the level of the margin. In others this membrane is calcified to a greater or less extent, and a solid lamina is thus formed, which protects a certain portion of the cell. Bui even in such species, in which this process of calcification is carried furthest, and almost the whole front is hardened into a solid wall, its position within and below the marginal rim at once indicates the mode of growth, and reveals the true Membraniijoridan structure'. That Sniitt has a similar view apjjears from his placing the family Cdlaiiidue, which has a completely calcified, depressed frontal wall, in his suborder Fliistrina. and from the following statement on the family Microporidae'". »Thus in the lull iie\elopnienl of the type, the primary area, in the same manner as in Escharina, disappears, and as this was the most pregnant character of the section Escharina, here, also, we perceive the close proximity of that group, although yet the plain front side and the raised pri- mary margins of Ihe zoa-cia remind us of the Flustrine nature*.
The answer to the question: whence the Ascophora have originated, is not quite so evident, as we have here a compensation sac, of which organ no trace
72, p. 179; ■' 22, p. 128; '' lO:!. p 13.
17
whatever has yet been (bund in any member of the division Aiuisca. Sniitl and Hiiicks have both given an answer to tliis question, i)ut as neither of them had any idea of the existence of this sac, the quite calcified, arched surface and the absence of the elevated margins were for them the most important differences from the other Cheiloslomata. At any rate both Hincks and Smitt declare that these forms cannot be traced directly from the Membraniporichte, l)ut that their origin must be sought for in the genus Meinbraniporella. Hincks' states in con- tinuation of the above-given citation: The passage to the old Lepralian type is not through such forms or through the genus Microporo, but through Mem- hraniporella in which the calcareous covering is an outgrowth from the margin of the cell, overarching as it were the original membranous covering*; and a similar view of this form's im])ortance as connecting link between the two men- tioned divisions is expressed l)y Smitt, both in his work on the Scandinavian Brgozoa and in »Floridan Bryozoa«-. In the last work he says: »In the above described MembraniporelUt Agdssizii we have seen one of the most evident con- necting links between the Flustrine and Escharine types*. Harmer has a similar view of the importance of the acanthostegous forms as connecting link between the anascous and ascophorous, and he seems in a preliminary paper ^ inclined to suj)pose that the whole division Ascophova had an acanthostegous origin, while in his main work*, he supports such an origin with certainty only for Umhoniila twrrncosd and for forms related to this species. Harmer in contrast to the two authors mentioned has given more detailed reasons for his view, which we must examine into here. Harmer has in fact observed, that the membrane, which originally alone represents the frontal wall in Umboniila verrucosa and {/. pavo- nella, gradually becomes covered by a calcareous layer arising from the posterior and lateral margins of the zooecium, which itself is covered by a mendirane (epitheca), and he therefore compares this process with that taking place in Membianiporella or Cribrilina in which the original membranous frontal wall is covered by two series of hollow spines. But while in the family Cribrilinidce the single spines at the outside are connected by lateral twigs they are in i'lnhoimld according to Harmer fused together into a two-layered lamina, tlie calcified layer of which corresponds to the basal (or inner) iialf of the spines while the mem- branous cover corresponds to the frontal (or outer) half. The author further finds points of comparison, partly in the circle of pores, which appear on the margin of the calcified frontal wall in U. verrucosa and U. pavonella, and partly in the radial buttresses which separate every two of such neighbouring pores and
' 22. p. 128; '■' 10;i. p. 21; ^ IH, p. Ki; * Hi, p. 2;).i, liUl.
18
fui in llie so-called areolae. The first of these is regarded as corresponding to the pores, through which the spines in a MembraniporeUa are connected with the cavity of the zocecium, and the latter is regarded as the adjoining edges of the spines which have formed the two-layered cover. Contrary to Harmer I must however regard the calcified frontal wall in C oernwusa and U. pavonella as a Cryptocyst. It has in reality its origin helow the primary covering membrane of the frontal wall, but there is soon formed on this a fold or out-i)ushing and the Cryptocyst (PI, XIX, fig. 2 b, cr.) grows inside this one, though it is only towards the end of the development of the zocrcinm that it reaches to the distal part, and thus the frontal wall in all younger zocecia shows two proximally directed arched or angular lines not far from each other and springing from the same ter- minal points (PI. XIX, fig. 2 a), of which the distal indicates the ti]) of the just men- tioned fold and the proximal the growing edge of the Cryptocyst. The same is tlie case in the species of the genus Rhaniphostomella (PI. XIX, fig. 19 a). Finally these supposed pores like the other so-named ])ores in the Bnjozoa are not at all apertures, but are filled by a membrane, which must be regarded as an uncalcified part of the wall. This membrane in Umboniiki as well as in many other cases is provided with several small perforations and we have really to do with super- ficial rosette-jjlates here (see rosette-plates and pores).
As is well known the first zooeciiim in a colony, the so-called primary zofpcium or »ancestrula' (Jullien), frequently shows characters dilTerent from those found in the later zoa-cia and not seldom such which are found in another division, family or genus. In the Cheilostomata it appears typically in the so-called »'/'((/« "-form (Smitt), the greatest peculiarity of which is the possession of a membranous frontal area, which in most cases is suri'ounded by spines and as this form of ancestrula is found not only in malacostegous and acanthostegous Cheilostomata but also in a number of genera {Schizoporella, Escharella, Escharoides, Microporella, Hippothoa), within the division Ascophora, Smitt' and later writers e. g. Harmer", who have studied the question of the genealogy of the Bryozoa, are no doubt quite right in regarding the Tata as an ancestral form of the Clieiloslonidla and the frequency of this Tata-Uke ancestrula as evidence that not only the Aiiasi-a but also the Ascophora descend from malacostegous forms.
While the ancestrula in some cases (Retepora Beaniana, ^Lepralia- Pallasuma, ^Lepr." spat hii life 1(1 (?), Sinittia reticulata) has the same structure as the common zocecia, in others it has such a structure that it must be regarded as a refiection of a later ancestral form, and sometimes we can even find in the same or in
' 103 a, p. 235; 99, p. 306; ' 19, p. 321.
19
nearly related species two or three different forms of aiicestruhe, which as it were represent different stages of the development which these forms have passed through during the lapse of time. The idea that the ascoporc, which appears in a number of genera, e. g. in Haploponui and Microporella, must have arisen from the closure of the sinus in a schizostomous orifice, has several times been expressed, and with this agrees the fact, that Haplopoma impressum (PI. XXII, fig. 9 a) as well as Hapl. corniitiim (PI. XXII, fig. 10 a) have an ancestrula with such an orifice. Neviani' has found an ancestrula with a similar orifice in Microporella Maliisii but in another colony he has found one of Tata-form and in a third the semicircular orifice of the ancestrula was contained in a calcareous region which is surrounded by short spines. A similar variation in the structure of the ancestrula has been found by Jullien- in the genua Hippothou (Diazeuxia Jullien). Harmer has given a list of 34 difl'erent ancestrulae described or pic- tured in the literature, and I may here point out that Smitt has besides pic- tured the ancestrula' of the following species: ^Lepraliai^ spathiilifera^ Escha- roides coccinea\ Porella hei>is-\ Escharella inunersu^, Esch. stenostonur and Esch. enmcronata^.
In all the hitherto found ancestrulse with a modified Tata, which belong to ascophorous families with a cryptocyst, there is found a more or less developed depressed cryptocyst, at any rate at the period when they have produced new zocecia, and the existence of this cryptocyst goes to prove, that these families descend from coilostegous forms. That Harmer" at any rate with respect to a part of these forms is of the same opinion is evident from what he says about the cryptocyst in the ancestrula of Eschariiui intlgaris: It appears to me to be of great importance to ascertain whether this calcified portion is of the nature of a cryptocyst or not; in other words whether the frontal membrane extends as far as the sharp ridge on the inner side of the base of the spines. I can hardly doubt that this is the case; and if so the Microporoid origin of Escharine forms in which the compensation sac develops as an invagination at the base of the operculum would appear to be indicated-. I may just remark, that Harmer's Microporoid series in all essentials corresponds with my division Coilostega and his Escharine forms with my Ascophora. — Such a transformation from a coilosteg- ous into an ascophorous form as that which Harmer and the author of the pre- sent work advocate, supposes, that the depressed or hollow cryptocyst of the former.
' 77a: * 45, p. 28-34; ' 100, I>1. XXVl, fig. 98; ' 100. PI. X.WII. tig. 162, 163; ' 100, I'l. XXVI,
fig. 109-111; « 100, Pi. XXVll, (ij;. 167; 101, PI. XXI, fig. 31; " 101, PI. XXI, Ug. 29; ' 101,
PI. XXI, tig 27; '•' Alf. p. 334.
I? 2*
20
has l)een in the course of time changed into an arclied one and this change was, I tiiink, a necessary supposition for the formation of a compensation sac, which could not find sufficient room within a depressed cryj)tocyst, and ii would therefore he reasonahle to su])pose, that this has only heeii formed after the depressed cryptocyst's transformation into an arched one. While we know of no example of an ascophorous form with depressed oral wall, we can on the other hand mention several examples of forms, which though helonging to the division Coilostega (or to the related division Pseudoslega) have a more or less arched frontal wall. In such cases either the whole frontal wall may he arched within a narrow projecting rim, or such a narrow rim may he wanting, and the largest portion of the frontal wall is then arched, while there is a smaller depressed portion in its distal or central part. We can mention the recent Cellaria magmfud Busk', Macroporct centralis (?) Mac dill. (I'l. VII, fig. 1 a), Micropora noduliferd Hincks^ and Aspidostoma (jitjanteum Busk (PI. Vic, fig. 2a), and the fossil 'Ilomolosteya" erecta Marss.', Aspidostoma (?) Atalantha d'Orh (PI. VI c, fig. 5 a, b), Aspid (?) Aegon d'Orh (PI. VI c, fig. 3 a) and » A'.sc/ian) Aegte d'Orh ^ as examples of species with such a structure. In the last sjjecies the frontal wall is arched in most of the zocrcia, while in a smaller numher it is more or less depressed or fiat.
In contrast to the modified 7'f//rt-form found in the genera Escliaroides, Escha- rella, Escharina and Porella (P. l(vi)is), which possesses a depressed calcareous lamina within the spines, the corresponding lamina in the modified Tata of Hippothoa hyalina found by Jullien' is not depressed but arched (bombe) and therefore does not seem to be a cryptocyst, but this corresponds very well with my exa- mination, according to which the frontal wall in that genus is a Gymnocyst. Busk" figures some abnormally developed zooecia of Electra pilosa, which are of no small interest. The spines are quite lacking in these, due to the fact that the calci- fication of the covering membrane has continued beyond the ordinary limit, so that the (lymnocyst has spread in irregular tongues over a large part of the surface, otherwise occupied by the membranous area of the aperture. In the frontal part of the two zooecia is an open .space which in shape and size might correspond to an operculum, and which is separated from the other calcified region by a low calcified bridge. It is evident that there has been an efTort here to form a zocecium with a perfectlj' calcified frontal wall, and by a similar elTort the Membvanipora species, which is rellected in the 7'((/«-form of Hippothoa hya- lina must in the course of time have changed into a Hippothoa, at the same time as
' 8, p. 93; ' 25. p. 1 1 ; ' .^S a. PI. IX. fig. 12; * m. PI. (Uii. fig. 6: '' 4,''). p. 30. PI. I, fig. 4 ; '' 2, PI. LXXI, figs. 3, 7.
21
Ihe iiol yel wliolly calcified |)arl of the Irontal iiiemltrane has loiined a compen- sation sac by an invagination proximally to the operculum.
The basal wall like the frontal may also be membranous, as in Membranipora mein- branacea and Electru pilosn, and even in numerous, well-calcified, incrusting mem- bers of the division Ascophora the basal wall is slightly calcified or jjarlly uncalcified, sometimes even quite membranous. I may for instance mention the incrusting species of the genera Eschaielbt. Escharina, Micropoielld, Hippothoa, etc. The ))asal wall in tlie calcified state seems as a rule to be a Gymnocyst, and it is only in very few cases that it is covered with a membrane in species appearing in free colonies. Harmer' has for example shown that the free, one-layered colonies of Euthyris dathratu and Eiith. obtecta (PI. XV, figs. 2c, 2d) are provided over the whole surface with a covering membrane which is kept stretched by ])ro- jections from the underlying Cryptocyst. A covering membrane over the whole surface of the colony is also j)resent in Urceolipora nana (PI. XV, figs. 1 a — 1 e) and it seems also to be found in species of the genus Cupiilaria.
Under the names of Sleginoj)ora and Uisteginopora d'Orbigny- has described a number of fossil species, which have possessed a double roof, of which the lower except in .S7. irregularis seems to have quite the same structure as the roof in Cribrilinidae and thus to be formed by spines connected with one another. On first consideration of the drawings given we should be inclined to supjjose that the upper roof is formed by calcification of such a projecting membrane as the one we find in Eulhijris ohtecta; but according to Jullien's^ investigations the upper roof is formed by a partial fusion together of very large spines, broadened out and plate-like at the ends, and this view is undoubtedly right. That this roof cannot be explained in the above-mentioned way appears clearly from the fact, that the membrane which corresponds with the mentioned projecting cover in Euthgris, has its place below the fused spines in Cribrilinidae. hi a number of fossil (Iribrilina forms as well as in the one-layered Steginopora species we find a varying number of robusj projections at the back of the single zocecia, which Harmer' thinks have served as sup|)orts for a membranous cover, similar to the one which is found in Eulhgris. Against this view speaks firstly Ihe circum- stance, that while the mentioned sui)ports in Euthgris obteclu are slender, cy- lindrical rods, the projections in the mentioned Cribrilina species, with which Harmer compares them, have the form of tubercles, which are very differently developed in number and size in Ihe different species, and their rounded end- ])art does not seem to have been connected with a membrane. Further, these
• 18, p. 16 and 19, pp 267, p. 277, 278: « 86, pp. 235, 498, 499; ' 44. p. 609; ' 18, p. H
22
knots may sometimes be present and sometimes absent, even in closely related species; thus while they are found in Semiescharipora ovalis^ they are wanting in Reptescharipora convexa". Secondly, we must remember that while the whole surface of the colony is covered by a continuous membrane in the Eiithijris species, every single zocecium in the mentioned fossil species has been furnished with a separate frontal membrane, which has been situated below the roof formed by the spines. As shown before, the marginal spines always spring from a Gymnocyst and we must therefore assume that the Gymnocysl, which has formed the spines of the marginal zocecia, has passed directly over into tlie basal wall of Ihe colony from the free lateral edges of these zooccia.
Rosette-Plates and Pores.
The adjoining zooecia in a colony are, as known, connected by chords of mesenchymatous tissue, which extend from one zocecium into another through pores in the partition-walk, but while these pores appear in the Cyclostomatu as simple perforations of the wall, they are in the Ctenostomata and Cheilostomata very fine piercings in watch-glass-shaped, concave, thinned portions of these walls. These peculiar formations have been noticed for the first time by Smitt, on the lateral walls in Flustra foliacea^ and are called bj' him commimication-pores. He has • not however seen the real pores, and seems to regard the whole, multiporous plate as an opening. Later Reichert'' in a member of the division Ctenostomata, Zoobolhrion pellucidiim, has observed the same formations, which he calls »Ro- settenplatlcns and in which he has seen the real pores. Among later writers Waters'' first drew attention to the importance of these rosette-plates for the diagnosis of species and in a series of papers he gives information on their presence in several Cheilostomata, while the writer of this work has illustrated their occurrence in the Danish species, .^s this description'' was however written in Danish, and for that reason less available, I may give here the results of those older investigations lo which I have been able to add by later studies. Though I do not find Ihe name rosette-plate good, I shall yet use it, jjartly in view of its priority and partly because Waters has used it in his many papers. The formations dealt with here may appear under two different forms, namely as common rosette-plates or as pore-chambeis, and each of these can again be divided into single-pored, or single and multi[)orous or compound.
Rosette-Plates. A single-pored rosette-plate is a watch-glass-shaped, concave, thin portion of the wall, which as a rule is surrounded by a more or less devel-
' Sfi, Fl. 719; » S6. PI. 72U; ' 99, p. 426, PI. X.\. tig. 15; * 94. p. 2l>7 ; '■ 109, p. 286; •■■ 54, 55.
23
oped, more chitiiiised projecting marginal |)ortion, »the pore-rings the onter open- ing of which in the most developed rosette-plates is smaller than the size of the plate a little in from it. Within the pore-ring we can distinguish hetween two portions, differing in thickness, a thicker outer area and an inner surrounded by the other, very much thinner and very small pore-area, which is pierced by an extremely fine pore, and distinguished by a strong bluish lustre, which at lirst glance makes it seem thickened. Such one-pored rosette-plates may appear singly (the distal wall of Flnstru seciirifrons, Fl. papyred etc., the distal wall of most Reteporid(te), in a more or less numerous (of 2 — f2 plates) series (all walls in many species of Sniittina, in Adeonidae, in mosl Fliistridae), or in groups some- times consisting of more scattered, sometimes of more closely placed plates (e. g. in Cotenariidae, the distal wall in Scrupocellaviidue and Thalamoporellidae). hi cases where tiie single rosette-plates are close together, they have a scjuare or hexagonal shape, and meet in a network of elevated ridges, which must be re- garded as the ])ore-rings for the single rosette-plates.
It is (juite impossible to draw a sharp limit between a group of one-i)ored rosette-plates and a multi])orous roselte-plafe, as the only character, which can be regarded as peculiar for the multiporous compound rosette-plate, namely, a common pore-ring which surrounds all the single small plates, can be developed to very different degrees, and does not always appear to be constant even in the same colony or in the same zooecium. This is the case with for instance Arthro- poma Cecili, in which species the distal wall as well as the distal half of each side wall is furnished with an elongated or oval group of numerous iiniporous rosette- plates. A pore-ring may be lacking on some walls and appear on others, not only in the same colony but also in the same zooecium, and wherever it appears, it may either be exceedingly well developed, or only slightly indicated. Within the pore-ring (PI. XVII, tigs. 10 a, 10 b) which has a similar structure as in the uni[)orous rosette-plate, we have an area, the large area, which may be tilled l)y the small plates to a very different degree, and while these for instance in Artliropomn Cecili often form only a longitudinal belt along the middle part, in ^Lepraliw Pallasiana (PI. XVII. (ig. 10 a) they fill the whole or at any rate the largest part of the plate. The rosette-plates may show many ditTerent degrees of calcification, to some extent according to the degree of calcification of the sjjecies concerned. In most members of the family Bicellnriidae, in species of the genus Onychocellci and Selenaria we thus lind rosette-plates, which with exception of the pore-ring are quite uncalcified; on the other hand we find e. g. in Fliislra foliacea and Flnstia carbacea, that the large area is calcified and the single small plates are uncalcified. The pore area is always uncalcified, while on the contrary the outer
24
area in mosl cases consists of an oiiler calcified, and an inner uncalcified part, and in strongly calcified species (e. g. ^Lepralia< Pallasiana) the inner uncalcified portion of the outer area is very small. The single small j)lates in a compound rosette-plate often show only a slight indication of a pore-ring, and when they are not much hollowed out the calcified portion of their outer area is often so little distinct from the large area, that it is only jiossihle lo find it hy very favour- able light. Just as we rather frequently find two rosette-plates fused together into a double plate with an outer area in common and two pore-areas in species, the distal wall of which is provided with a number of uniporous rosette-plates (e. g. in Fliistra foliacea, Fl. carbacea and Membranipora pilosa), we also find in a multiporous rosette-plate a fusion of two or more small plates into one. A great deal of variation and very dilTerenl kinds of fusion take place in the distal w-all in Membr. membranacea^. In this appear as a rule two pear-shaped multi- porous rosette-plates, but in many zooecia each of these is replaced by a whole series of smaller plates, of which some are uniporous, others multiporous with a very varying number of pores; the conditions may even be (juite dilTerent on the two sides of the distal wall.
Pore-CJiambers. I have used this name" for the small spaces which are situated in the angle between the basal wall of a zooecium and one of the perpendicular walls. In their typical form they have a triangular tranverse section, and we can distinguish between a basal wall, an inner wall and an outer one. The basal wall is a portion of the basal wall of the zooecium, the small rosette-plates are situated on the inner wall, and on the outer wall is the entrance to the chamber (PI. XVII, tig. 10 c). If we examine their development in the newly formed zooe- cia in the growing part of the colonv', we see that the inner wall is the part first formed and that the basal wall and outer wall are formed later. We can best make sure of their presence if we loosen a colony from its supi)ort and look at it from the basal surface; for in this position the inner walls of the elongated pore-chambers form curves within the lateral margins of the zooecium (PI. IX, ligs. 11 g, 12 a, PI. XV, figs. ;5c, 4 c, PI. XVIII, figs. 14 b, 11 a). There is as a rule only a small number of sniall plates ])laced in a single row and the neigh- bouring chambers arc in most cases moved up so close together that the curves touch one another, oi' even so that the chambers have a common separating wall. While the vertical walls in all zoo'cia, which are furnished with ordinary rosette-plates, form right angles with the basal wall, the pore chambers are placed in such a way that their outer wall forms pointed angles with the
' 54, Tab. II, fi)5. 17: .55, PI. IV, fig. 5; '' 54, p. 2,50: 55, p. 7.
25
basal wall of the one and obtuse angles with the other of the two zooecia, between which it serves as connection (PI. XVII, fig. 10 c). The outer wall of the chamber forms obtuse angles with the frontal wall of the zoa>ciuni and the pore-bearing, somewhat slightly concave inner wall forms obtuse angles in- wardly and pointed angles outwardly with the base. What is said here applies to the pore-chambers of both the lateral and distal walls. Though rosette-i)lates and pore-chambers seem at first glance to be of quite different structure, they are connected by transitions. If we imagine a rosette-plate placed in such a way thai its lower edge goes down into the angle between a lateral wall (or distal wall) and the basal wall, a removal of this edge into the basal wall would produce a pore-chamber, as what is just characteristic for such a formation is, that it belongs to two adjoining walls. I have found such transitions between common rosetfe-plates and pore-chambers in colonies of ^Lepraliw^ Pallasiana from Sebastopol, which together with Electra Zostericola forms incrustations on Zostera marina. While colonies of this species from Denmark and from Port Jackson, New S. Wales, have only ordinary multiporous rosette-plales, we find more or fewer zooecia in the colonies mentioned from Sebastopol, in which more or fewer rosette-plates are replaced by pore-chambers with differently developed basal wall. We can also find such transitions in the very variable species Porella concinna between rosette-plates and pore-chambers, which replace one another in different colonies. In contrast to the multiporous chambers which can be found in ^Lepralia< Palla- siana and Porella concinna the few-pored chambers are usually constant within the species, and even sometimes in the genus or family. Besides in all members of the families Hippothoidae and V.elleporidae typical pore-chambers appear in the genera Callopora, Cribrilina, Puellina, Eschar ina and in a number of species of the genera Escharoides and Microporella. In the members of the family Celle- poridae. the colonies of which increase by superficial budding, the pore-chambers are only to be found in the zocccia which form the llrsl incrusting layer of the colony; in species of Escluirella (PI. XVII, fig. 1 c) the originally long and narrow pore-chambers, which are provided with a row of small single-pored ro- sette-plates, are divided by partition walls into a number of uniporous chambers, and the pore-chambers may be tubularly lengthened in .species of the genus Hippothoa.
Before discussing the relation of a rosette-plate to the two zooecia which it connects, we may again recall that on using boiling alkali or cold eau de .la- velle we can not only loosen a colony from its support, but even as a rule sepa- rate it info single rows of zoa-cia, on which wc can without difficulty study the
2f)
roselle-jilales. While Xilsche' in his nl)ove-inenli()iu'(i work on Meinhr. mein- branncca has rightly ohserveii, that the single zorecia have independent lateral walls, he gives a wrong view of the relation of the single zoa^cia to the rosette- plates. He saj's namely: »Die Rosettenplatten eines jeden Zoociuni eorrespon- diren nun mit den Rosettenplatten der uniliegenden Zoocien auf das genaueste*, and he gives in detail an explicit account of how the rosette-plales of each zoceciuni are placed opposite to a corresj)onding rosette-plate in an adjoining zooecium. If for instance we separate a row of zod-cia of a ScriijxH-clldrid form (PI. II. figs. 7 g, <S c) each lateral wall in its distal half will show a inultijjorous rosette-plate, hut in its proximal half an opening of the same sliajje and size. If we subject Flustra foliacea (PI. I, fig. 81)) to the same treatment, we find 2( — 3) multiporous rosette-plates on its distal half, and '2{- \i) openings on its proximal half. Because of the arrangement of the zonecia in alternating longitudinal rows, one or more openings in the proximal half of a lateral wall will always correspond to and fit exactly o))posite the same number of rosette-plales in the distal half of the corresj)onding lateral wall of the adjoining zooecium. In (ie- mellariu loricata we have an example of a form, the zod'cia of which in contrast to the ordinary conditions are arranged in pairs. Each two of these zoa-cia are as a rule connected by a single rosette-plate, which only belongs to the one zoa'cium, while the opposite one has a corresponding opening in the wall. We may examine ever so many forms in this regard, but we will never find two rosette-plates opposite each other, but a rosette-plate on one wall always corre- sponds with an opening on the ojjposite wall. Strictly speaking the rosette-plate, as well as the apparently single lateral wall between two adjoining zocecia, is also divided into two halves (PI. \\'II, tig. 10 b), which however in the case of the rosette-plate are very unequal in size, as the concave pore-bearing portion belongs to the one wall, while the oj)|)osite wall includes Ihe pore-iing, which can then be seen on the inner (towards the inside of the corresj)onding zoo-cium) surface of this wall as a more or less circular projection round the above-men- tioned opening. The rosette-plates are arched inwardly towards the proximal zooecium on the terminal partition-wall, which as already said is common to two zocecia situated behind each other. The above-discussed arrangement of the rosette-plates can be illustrated in a very clear way by means of a variety of Flustra seciirifrons" with narrow branches found in the Kara Sea, in which the rather numerous uniporous rosette-plates are unusually strongly arched, so that they can be seen llnough the membranous oral wall. Inwardly arched rosette-
^0 ».i/i,
53, I'l. .\.\V1, lig 9.
27
plates are here only seen in llie distal lialf of llie zocecium. and the first, out- wardly arched plate, which can be seen proximally to the margin of the distal wall, only apparently forms an exception to the rnle, because, namely, the distal wall ascends oblitpiely from the basal towards the frontal wall, and this plate belongs really to the distal zoo'cium. We can easily convince ourselves that the same law apjjlics to the [)ore-chambers if we examine the basal wall of a colony, which has such, as the lines in which the pore-chambers meet the basal wall shine through on its surface (PI. IX, figs. 11 g, 12 a, PI. XV, lig. ^ c). If we sepa- rate a row of zooecia of a species which has well-developed pore-chambers, we find that a transverse section of the distal and proximal portions of a zocecium has a very varying form, because the basal part of the lateral walls (or outer walls of the pore-chambers) in the distal half of the zocecium meets the basal wall at a pointed angle (PI. XVII, fig. 10 c), while the corresponding poi tion of the lateral walls in the proximal portion of the zoa'cium, which is jirovided with openings to the pore-chambers, forms an obtuse angle with the basal wall. It is evident fiom this that the zorrcia of such a species, seen from the basal wall, are more or less plainly rhombic, even if when seen from the frontal surface they have an oval or rounded shape '. As the outer wall of the pore-chambers, as said before, forms obtuse angles with the frontal surface of the zocecium the distal half of such a zoiccium will be surrounded by a marginal expansion (PI. XVII, ligs. 1 a, 1 c), formed by the pore-chamber. This expansion which in older zooecia is covered by the surrounding neighbouring zooecia may be easily seen in the marginal zowcia of a growing colony. Just as the opening on the rosette- plate is smaller than its extent a little way inside this (fig. 10 ])), the same ap- plies to the opening of the j)ore-chamber, which is limited bj' two, more or less developed plates belonging to the outer wall, which plates we may call »lips«. They thus play a similar part to the projecting marginal portion of the rosette- plate which we have called the pore-ring, but while the latter always belongs to the op|)Osite zocrcium the lips here are a part of the real pore-chamber, and the opposite zoa'cium has only an opening corresponding to the opening between the lips.
In expressing as above the law with regard to the relation between the ro- sette-plates and the single zocecium, namely, that the distal half of the zocKCium is furnished with rosette-plates and the proximal with corresponding openings, it should be understood that the word half, taken in a more restricted sense, only applies to such zoa'cia as are arranged in regular quincunx, i. e. so that a
' 54, PI. II, figs. 'J7— 33, 55, PI. IV, fij>s, 22— M.
2.S
lerminal parlition-wall helvveeii Iwo zod'cia (ils riglil ()pj)Osile to a latei'al wall in an adjoining zoa'ciuni. On the other hand, if two adjoining zoa'cia are placed in a diflerent relation to one another, the distribution of the rosetle-plates and the oj)enings will also change. Even in those colonies where the (piincunx arrangement is most regular, we will sometimes he ahle to find j)laces where more or fewer zoa'cia are arranged in a less regular way. If now two adjoining zoa'cia, for instance in Fhtxlra foliacea, are so placed in relation to one another that the one i)rojects beyond the other by a quarter of its length, this ([uarter will he provided with a rosette-plate, while the other part of the lateral wall has nothing hut 0])enings, which correspond \\\[b the same number of plates in tlie adjoining zocrcium. The law ought really to be expressed. in this way, that the part of the lateral wall of a zoo'cium, which extends beyond the distal wall of the adjoining zocecium, is furnished with rosette-plates, while the portion be- hind has openings. While most Cheilostoumla are arranged in more or less regular quincunx, there are on the other hand species in which this arrangement can only be seen here and there, while the zoa'cia are principally arranged in more or less regular transverse lines. This is for instance the case in Sinilliun (Schizoporella) linearis, and most of the zooecia here will have either only rosette- plates or only openings on the side-walls. There is also a strong inclination to such an arrangement in Memhranipora nionostachys, and it is not unusual that a whole row of connected lateral walls have either only rosette-plates or only openings. Electra pilosd forms a peculiar exception from the common rule, and very likely this is also the case with the other Electra species. Although as a rule we have the true quincunx arrangement in tliis species, yet in a whole row of zoa-cia on the same side we either find only rosette-plates or only openings. This difference is how- ever accompanied l)y another, as the lateral walls which bear the rosette-plates are always much thicker and more strongly calcified than those with openings, and the last are very thin and after boiling in alkali often partly destroyed. We can now and then find a whole row of zocecia, the lateral walls in which are thick and furnished with rosette-plates, but then both the corresponding rows of adjoining walls are thin and have openings.
We have up to the present only discussed the appearance of the rosette-plates on the vertical walls, but they may appear on the basal wall (posterior wall) as well as on the frontal surface, and in tlie first case both in two-laj'ered and in one-layered colonies. Thus, in two-layered colonies, I have found tluni in SiuHtiim palinaia (PI. XIX, fig. 5 ))), Porella saccata Por. coinpressa, I'hdUujtopo- rella lioiichu (PI. VI, fig. 7 i), Sle(janoporella magnilabris (PI. V, fig. 5 b), Diinorplio- zoiim nobile (PI. IV, fig. 1 c, 1 d), Micrupurella llabellaris (PI. XV, fig. 4 c) and Micr.
29
marginata (PI. XV, fig. 'A c). On Ihe otlier hand they are lacking for instance in Fliistra foliacea and Fl. seciirijions. They appear in the same way as the rosette- plates on the vertical walls, a rosettc-j)lale on a zooeciuni in the one layer corre- sponding with an opening in the opposite layer, but in none of the mentioned species are they found in all zofficia of a colony, though for the rest they ap- pear in very varying numbers. While they thus appear very scattered in Steg. magnilabris, they are found on by far the most zooecia of Microporella flabellaris and Mic. marginata, and in the last species the connection between the zooecia is as a rule a double one, every zocecium possessing a rosette-plate as well as an opening.
Rosette-plates or pore-chambers may also appear on the basal wall of colonies with one layer. We thus find a number of uncalcified uniporous rosette-plates in liutliyiis obtecta (PI. XV, fig. 2 b) and E. chhitrata ' where tiiey might be con- sidered as uniting the interior of the zocecium with the space, which is bounded by the covering membrane, while a number of basal uniporous rosette-plates in Hiantopora radicifera (PI. IV, fig. 6 b) serve as origin for the radical fibres which fasten the colony to its support. In the family which I have called Petraliidae, the species of which mostly appear in free colonies with one layer, the free basal wall is cither furnished with rosette-plates or with pore-chambers from which radical fibres sometimes issue (e. g. in Petralia tuberosa Busk^ and P. dorsiporosa Busk").
We will now consider the appearance of the rosette-plates on the frontal sur- face. Busk' has already called attention to the fact that the species which he de- scribes as Carbasea Moseleyi, possesses a number of formations in the distal half of the zocecium, which quite correspond to rosette-plates, and these plates are also found in the distal part of the frontal wall in Onchoporella boiDbijcina (PI. XIII, fig. 9 a, 9 f), Onchopora Sinclairi (PI. XIII, fig. 7 a, 7 b), CalwelUa bicornis (PI. XIII, fig. 8 a) and Onch. deirtata (PI. XIII, fig. 6 b), all of which species I refer to the family Onchoporidae, and to this family ■Carbaxea^ Moseleyi and Iclithyariu oculata Busk ' also jjrobably belong. The rosette-philes in those species examined by me are furnished with a strongly developed pore-ring projecting into the interior of the zoa'cium and are either round, uniporous or longitudinal, narrow and as if formed by a fusion together of from two to four uniporous plates placed in one row. To judge from figs. 4 a and 4 b the roselte-jjlates seem also to be uniporous in -^ (la r based" Moseleyi, and the 8 — 10 small red spots, which Busk has found on the rosette-plates of the specimen stained with carmine,
' 19, I'l. .\VI, fig. 22; - 8, HI. .Wll, fig. 7 d, PI. XVIII, fig 4 b, '■' 8. p. :>1 : ' 8, p. 48.
30
might be leucocytes, which can often be loimd fixed to the inner surfai-e of many rosette-plates and which can easily l)e taken for pore-areas. Kiithijris ohtecta (P\. XV, fig. 2 a) and UrceoUpora nana Mac Gill. (PI. XV, fig. 1 a) are also furnished with rosette-plates, and the marginal |)ores, which ap[)ear in a single or ilouble row in numerous Cheilostomata, seem always to be rosette-plates, which are usually furnished with a single pore-area. We can for instance mention Escharella immersa, Escharoides coccinea, Porella strnma and Smittina palmata. These rosette-plates are always without a pore-ring and are (|uite membra- nous, for which reason they quite disapi)ear when boiled in alkali. Some- times in many species — for instance in the species of Celleporn and Holo- porelhi — they may come to lie at the bottom of shorter or longer canals, partly by the calcareous wall's growing in thickness, partly i)ecause the calci- fication takes place in such a way that the canals leading to these rosette-plates pierce the calcareous wall under very pointed angles. Such long canals can for instance be found in Tessaradoma borealis and Escharella spinosissinm^, and espec- ially in the last species they are remarkable for their considerable length, so that even some of them may reach from the marginal portion almost right in to the middle line of the frontal wall. In other species these marginal pores are enclosed or overbuilt by small calcareous spaces which are furnished with a larger or smaller opening and which we may compare with the above-mentioned pore-chambers. We may mention Sniittina reticulata, Sm. palmata (PI. XIX, fig. 5 a), Escharella variolosa, Discopora verrucosa and Disc, pavonella as examj)les of species which possess such well-developed marginal cavities or areola'. The three or four- sided areolae are outwardly limited by a projecting line, which is simply a contin- uation of the lateral wall of the zocecium, and are separated from one another by a number of transverse buttresses, which grow in length with age and in older zoa^cia even touch one another in the middle of the zoa>ciuni. Two ad- joining lateral ridges will, as is the case with the lateral walls from which they spring, after boiling in alkali solution separate from one another, and if we look at such a separated row of zoo^cia from the side we see these lateral spaces through the wall as light canals, which on superficial observation would seem to belong to the lateral walls. Still we must remember that the rosette-plates which lie at the bottom of these spaces are really placed on the frontal wall. It is not in all cases however that the superficial pore-chambers are externally hounded by such a projecting ridge; this is not the case e. g. in Escharoides Jacksoni, in which species these spaces are short, sac-like with an aperture facing
' 34. PI. III. fig. 3.
31
towards the cenlre of the zod'cium. [ii JhiswvUin (iiistraliensis and Hasiv. coronata the frontal wall is furnished with muiuMoiis pore-canals, each ending inwardly in a uniporous roselte-plate and as the rosette-plates helonging to the marginal pore-canals have their place in the outer pari of the lateral walls, these rosette- plates thus form a connecting link hetween the common lateral rosette-plates and those belonging to the frontal wall. In species of the genus Myriozoum the whole of the frontal wall is furnished with closely placed, posteriorly directed sac-like pore- canals, each ending in a uniporous rosetle-plate (PI. XIX, lig. Hi a). In each canal is a chord of mesenchymatous tissue, which has a club-shaped widening towards the ro- sette-plate. In Srlerodoinns denticiilatux (PI. XIX, fig. 18 a, 18 b) the frontal wall of the zoo'cium is furnished with minieious curved, sac-like and widened pore-canals, which contain a similar chord of mesenchymatous tissue. Finallj', I may mention that in all the species which have marginal pores and at the same time a median avicularium proximally to the aperture, the avicularium stands in connection with the llrst or sometimes also with the second pair of superficial rosette-plates, respec- tively through two or four shorter or longer canals, which issue from the distal part of the avicularian chambers. This is the case for instance with most species of the genus Porella.
AH other so-called pores in the Cheilostonmta are, as Per gens has already remarked, not real pores, and when this writer' states »ces petits pores sont, en realite, des cavites intersqueletliques occupees par du tissu epidermiijue, en con- nection avec ies parties scjuelettiques et avec le parenchyme«, this so far agrees with my observations, as I have always found the bottom of these pores closed by a membrane, which adheres directly to the calcareous skeleton and may with age be calcified to a more or less extent. In some of the species, for instance in 'Lepralid' Pallasiana, a larger or smaller number of these pores may eventually become closed, and in Siniltina jmrifera they may assume a very dilTerent appea- rance according to the different manner in which calcification proceeds. This membranous area in Microporina horealis is divided into a number of small areas by radiating calcareous ridges. The difference between such a j)ore and a rosette- plate is therefore only, that the latter is furnished with one or more very fine perforations, which are absent in the former. The pores as well as the marginal rosette-plates may as time goes on become surrounded by small chambers, and for instance in Sinittiim povifera and ■ Lepralia« Pullasinna a meshwork of ridges is formed over the whole surface. Regarding the pores of the ooecia, I need only remark that they are similar to those of the zoo^cia.
' 93, p. 308.
32
The Compensation-Sac.
The compensation-sac was first noticed by Jul lien', hut llie descrip- tion which tliis writer f^ives of this iniporlaul organ is not very detailed, and this might be one of the reasons why Jul lien's discovery has either been quite overlooked or received with distrust by all later writers, until Harmer- redis- covered this organ and gave a fuller account of it. While I do not agree with Harmer in his view of the structure and development of the compensation-sac in Discopora verrucosa and the forms grouped with this species, my investigations agree otherwise with the general view he gives of this organ. It is a large thin- walled sac, which in the Cheilostomata provided with an arched calcified frontal wall (Ascophora mihi) lies immediately under this in the whole or the largest part of its extent and oj)ens outwards either immediately jjroximally to the o])erculum, or occasionally further back, through an unpaired median opening, an ascopore« (Micro- porella, Inversiiila, Tiihucellarid, Onchoporella, Haplopoma, Adeona). Its inner wall, which is attached distally to the proximal edge of the operculum, is on each side furnished with a row of muscular bundles, which in arrangement, grouping and attachment to the inner surface of the calcified lateral walls, correspond perfectly with the parietal muscles in the Malacostega, and there is no doubt that they have the same signification as the.se, because their contraction will extend the sac, thus causing it to be filled with water through its external opening with the final result that the polypide is extended. The observations made with regard to the first l)eginnings of this sac scarcely leave any doubt, that as a rule it is formed as an invagination of the original membranous frontal wall of the zooecium, whether the wall later on retains its membranous condition as in all groups furnished with a cryptocyst, or later becomes calcified as in Hippotlioulde and Cdleiutriklitc. The first trace generally appears rather late, either distally to the operculum or to the median pore, and from there it gradually .spreads over the rest of the frontal wall. A somewhat ditfex-ent mode of formation is found however in Disco- pora verrucosa and related forms. While Harmer"' looks upou the compensation- sac as a true sac provided both with an inner and an outer membranous wall in all other forms examined by him, he has quite a different view of the corre- sponding formation in the above-mentioned forms. He states namely, that in these the membranous frontal wall provided with parietal muscles, which is seen on the (piilc young zoo'cia, later becomes covered by a fold, springing from the proximal and lateral margins, the inner lamella of which is calcareous and the superficial layer membranous, and the compensation-sac formed by Ibis
' 45 a. p. 67—68; ' 18 and 19: ' lit, p. 293—297.
;53
process possesses only an inner, membranons wall. Ihe outer being calcareous. According to my investigations the fold wbicb gradually covers the original membranous frontal wall is an evagination of this wall itself and therefore con- sists of two nienibranous layers, an inner which together with the primary frontal membrane forms ■ the compensation-sac and an outer which forms the frontal membrane of the adult zooecium. The calcareous layer seen within the covering membrane in the proximal part of the zoai-cium, is a cryptocyst which grows into the cavity of the fold but only reaches its tip in the adult zoa^cia, and therefore in all not quite developed zooecia we see a curved or angularly bent line marking the free edge of this calcareous layer (PI. XIX, lig. 2 a) proxi- mally to the growing edge of the fold.
To make certain I have examined a number of longitudinal sections made with the aid of the microtome of L'nibonuld pavonella (PI. XIX, fig. 2 b), in which the compensation-sac seems to show the same conditions as are found in U. verrucosa. The reason why I preferred the former species is only that our Museum's spirit-material of this species is of somewhat more recent dale. Though the sections examined are not good, they are sufficient to establish the correctness of my view. While all the membranous or cellular portions are strongly stained and easily recognizable, which for example ajjplies to the frontal membrane and the compensation-sac, all the calcareous walls appear as faintly stained, verj' fine lines. The ascending distal walls are more or less broken or folded in most of the sections, and this is also the case with the cryptocyst (cr) lying in the interior of the frontal evagination. Sections of younger zooecia are only different in that the evagination is shorter.
Harmer has already drawn attention to the fact, that the above-mentioned 'Miicronellu< pavonella must be referred to the same genus as Ihnbomila verrucosa (Discopora), and to the same genus I must also refer the species of v. Lorenlz's' genus Ramphostomella. In all the.se species the primary frontal membrane forms an evagination which encloses the cryptocyst and in young zocecia of a certain development we see the free edge of this cryptocyst proximally to the free edge of the evagination (PI. XIX, fig. 19 a).
Vestibulum.
Within the recent Bryozoa, as is known, an operculum only appears in the Cheilostomata, which in other respects are distiuguislu-d from the Ctenoslomala
' 58, p.
34
by being more or less calcified as well as by having avicularia and ooecia. The possession of an operculum has been rightly regarded as the most important of the characters mentioned here, and it is Iherelbre so much tlie more of interest that ^^'aters' has shown that an operculum is lacking in the nutritive individuals of the genus Buyiila. Nevertheless, that the species of this genus must certainly be regarded as Cheilostomota is evident, not only from the fact that they ])oss('ss the other Cheilostome characters and are very closely related to the Bkelluria and other genera with an operculum, but also from the fact that they all have avicu- laria, ■which always have an operculum. Nitsche^ has pointed out, and other writers confirmed, that the tentacular sheath from the proximal part of the zooecium whence the polypide originates, grows forward as a solid chord, which is fastened to the inner frontal surface of the zooecium in its distal part. Later, this chord obtains an inner cavity, whicli opens outwardly through a slit in the frontal wall of the zooecium, and it is evident from this that the difference be- tween the structure and development of the aperture in the CheilostonuiUt and CJeno- stomata is conditioned by the difi'erent ways in which this chord-shaped formation is fastened to the inner surface of the zooecium. In the Cheilostomata this attach- ment lakes place in a semi-circular line and this results in the formation of a semi-circular opercular valve. As is known'', we can distinguish in the tentacular sheath between two difi'erent regions: the true tentacular sheath, which in the retracted condition of the polypide encloses the tentacles, and a distal region, the vcslihulum, which can be shut off from the true tentacular sheath by a mus- cular segment, the diaphragm, and as we shall see later the vestibulum may even in certain cases have another closing-apparatus j)laced distally to the diaphragm. As I have nowhere found in the literature a satisfactory account of the way in which the vestibulum is connected with the operculum as well as with the aper- ture of the zooecium, I will try to give such here. If we imagine a zooecium with the operculum (|uite open, but with the [lolypide drawn in, we can distinguish in the vcstibuliun between an inner or zocecial, and an outer or opercular portion, of which the lirst is fastened to the edge of the aperture, and the latter to or a little within the edge of the operculum. liesides the two portions mentioned we also have on each side a triangular lateral portion (PI. XIII, fig. 7 a) which con- nects the zocecial and the opercular portions with each other, and which is folded into the vestibulum when the operculum is closed. The comparison between the vestibulum and a valved purse, the two metal guards of which might respectively correspond with the rim of the aperture and the rim of the operculum, which is
'111, p. 12; ' 8U, p. JJf— >S; ^ 19, p. 272.
35
used by several writers, is therefore not quite correct, and it would be far more correct to compare it with a division in a modern purse, in which the lateral walls when the purse is closed are folded into this. To explain the formation of such a vestibulum a simple horizontal dividing of the flat vestibular rudiment is not sufficient, as this would only lead to the formation of the zocecial and the opercular walls. To explain the formation of the two free lateral walls it must, I think, be necessary to suppose that an invagination on each side has taken place togetlier with the division of the chord-shaped rudiment.
The distal part of the vestibulum presents a number of dilferences, partly in the way in which it is fastened to the operculum, partly in its structure and nature, and we may here shortly mention some of the differences, the closer study of which however will recpiire fresh investigation-material. While its frontal wall in a number of forms is fixed directly to the free edge of the operculum, as in most Fliistra species, Membrduipora meinbranacea, Electra pilosa, Geinellaria loricata, Micropoiiim boredlis, Sciiticella platjiosloma, Retepora Beaniaiui, etc., in a number of other species it is fixed at a shorter or longer distance within the edge, in such a way that we must conclude that the frontal and liasal walls have moved from each other after the division of the vestibular rudiment. For instance we find this the case in Fliistra abiisskoht, 11. carbasea, in numerous members of the family Membraniporidae {Callopora mirita, Tctjelbt unicornis, Memb. arctica etc.), in the family Scriipuci'lldriidae, in the genera Stajdnopurella, BicdUiria and Discopora, in 'Lepraliu' Palhisiana, Tiibiicellaria opunliuides etc. In most of the Cheilosloinata, and as it seems in all Anaska as well as in numerous Ascophorn, the part of the frontal wall of the vestibulum, which adjoins the operculum, is more or less chitinized, whether this connection takes place in or within the edge of the oper- culum, and when such an operculum is isolated the chitinized portion of the vestibulum adheres to it as an arched chitinous ridge (the -opercular arch< ) rising from its inner surface, which is lowest at its distal, central [>art, but which gener- rally on each side ends in a more or less triangular »flange<=, which is a part of the above-mentioned lateral wall of the vestibulum and which goes directly over into the membranous part of this. If we compare opcrcula of the youngest and the oldest zooecia in a colony, we sometimes (e. g. in Microporina borealis) find that the opercular arch is higher on the latter, and now and then this opercular arch shows distinct lines of growth. There is a cavity between the operculum and the frontal part of the veslibulum, the opercular cavity, and into this extend the occlusor muscles of the operculum, which in the forms with a well-developed opercular arch are generally fastened to this; if not, the oi)ercular muscles are
attached to the inner surface of the operculum itself.
3*
36
Just as the part of the frontal wall of the vestibiiliim, which is connected with the operculum, may he chitinized, this may also he the case with a larger or smaller part of the inner wall of the vestihulum, as e. g. in Euthyris clathrata described by Harmer', in which species this writer has described a vestibular sphincter apparatus, similar to that which Hi neks'- formerly noticed in Eiirysto- melhi hihihiatd. In E. clalhrala^ the somewhat chitinized inner part of the vesti- hulum (irsl bends inwards and downwards into the zod'cium and then again bends forwards and upwards in a semicircular fold, the chitinized part of which (labium) in the closed condition of the vestihulum, (its closely to the above- mentioned opercular arch, which in this way forms an under lip, while the labium forms the upper lip. Also in Euthyris ubiecia according to Harmer's investigations there is a delicate labium. Hincks was the first to find a two-lipped vestihulum in "Lcpraliu" bilabiala, and as I have been able by the great kindness of Professor Whi leaves to examine Hincks' original specimen, I can confirm that the sphincter-ap[)aratus like that in E. clathrata consists of an upper lip (labium), formed by the inner j)ortion of the vestihulum, and an under lip, formed by the opercular arch, which Hincks calls »a semicircular chili- nous rim, as it were soldered to the inner surface of the operculums. I have found a quite similar two-lipped vestihulum in the closely connected species Li'pralia' foraminUjerd, while I have found a vestibular two-lipped Sphincter- apparatus of an essentially diilerent structure in the genus Sleyanoporella. It is placed at the proximal part of the operculum, and consists of two (juite similar semicircular lips slightly chitinized at the free margin, both of which are folds of the vestihulum and have no connection with the opercular arch. From the zooecial aperture's distal rim or anter in quite a number of forms there sj)rings a more or less developed, calcified portion reaching into the zocecium, in most cases in the form of a low, arch-shaped calcareous ridge, which seems to have originated from a partial calcification of the inner or basal portion of the ves- tihulum. Such a structure, which we may call a »\estibular arch«, is found in the family Reteporulae (PI. XXill, figs. 4 a — c), where it is as a rule crenulated, in Macro- pora centralis Mac Gill. (PI. VII, fig. 1 a), in most species of the genus Microporella (PI. XV), and in the genera Escharina (PI. XVIII), Escharella (PI. XVII) and Eschuroides (PI. XVII, figs. 5 b, c). It reaches its highest development in the two last-menlioned genera, and it is shown plainly in a number of figures in Busk's Crag Polyzoa '. The species which shows the highest degree of development of this portion is Escharella iliaphana Mac Gill. (PI. XVII, figs. 1 c, 1 ri), and it is here in llie same
' 19, p. -HMS: 5 .il p. >S^ ' 7, I'l. VI, ligs. 4. 8; I'l. VII, litJs. 1, ;t etc.
37
manner as the above-mentioned chilinous region in Eiilhyris cUithiuUd bent strongly basally and afterwards again frontally so that it forms a hood-shaped cavilv with a frontal concavity. This vestibular arch, which arises from Ihe distal rim of the primary aperture must not be confounded with the arch-shaped cryplocyst-ridge, which in a number of species of the genera Stetjanoporella (PI. V, ligs. 5 a, G a, 3 a) and Thalamoporella is placed between the basal (horizontal), and the frontal (obliquely ascending) portion of the distal wall. Waters' who was the first to speak about it calls it an oral shelf. It was later mentioned by Harmer^'.
The operculum.
In lis simplest form the operculum is a semicircular membranous valve, which passes evenly over into the frontal membrane and is only cbifinous where it meets with the opercular arch. We might give a line running belween the two corners of the opercular valve as a border towards the frontal membrane, and round this line, the hinge-line, the valve turns during the folding in and out of the polypide. Such an opercular form can be found in most of the Malacostega, in a number of Coilostef/a, as also in not a few members of the division Ascophora.
In contrast to the oj)ercular form just described, in other forms we meet with an opercular valve which is separated in different ways from the frontal mem- brane, and in the simplest cases by its proximal rim being furnished wilh a chitinized thickening (basal sclerite, Harmer), which on each side is connected with the chitinous opercular arch. Besides in Clilidonia Cordieri and most Stega- noporella species (PI. V, fig. 3 c) such an operculum is found in a number of species of the genus Thalamoporella, e. g. in Th. e.vp(iiis(t (Pi. VI b, fig 5 b), Th. iimmillaris, Th. Jervoisii (PL Via, fig. 4 c), etc., while in other Thalumoporellu forms the operculum is only partially separated from the frontal membrane by means of a shorter or longer basal sclerite on each side (see PI. VI b, lig. 6 a). The opercular valve can also be seen either entirely chitinized or calcified, and I have already mentioned earlier the few recent species which possess a calcified opercular valve. Within the group Malacostega I have found a completely chiti- nized operculum both in some, not yet described Oiujchocetla-spcvies (PI. XXII, rig.;U)) and in some members of the family Scrupocellariidae, namely in Caberca Uoryi and Cab. Darwini Busk and in a new Scrnpocellaria species. In these three species the operculum is enclosed by a comi)lelely calcified rim, the proximal jiarl being bounded sometimes by two projections from tlie calcified lateial parts of the zocecium (C. Darwini), sometimes also by the here higlily developed plate-like
• 107 a, p. .'•.1; " 17, p. 227.
38
spine, which as is known appeal's in very different degrees of development in a number of members of this family. As a similar enclosure of the operculum is also found in Menipea liausd Busk ', Men. Je/freysi Norman - and Scnipocellaria mar- supiata Jull.^, it seems i)robable that the operculum in these species has a similar structure. Besides in the species just mentioned, we find an independent opercular valve in the Coilostegous genera Micrnpora and CeUiilarut, and in the genera of the division Ascophora: Microporellu, IiuxTsiiila, Onchopora, Vrceoliporu, Clwrizopora, Haplopoma, Adennellopsis and Tubncellarin. While we may briefly call such an operculum as appears in most of the Malacostei/d an opercular valve, I would propose the designation »simple o])erculum« for any opercular valve, which is distinctly marked off from the frontal, membrane, and can consecjuently be isolated as an independent formation. While the proximal edge of such an oi)erculum forms as a rule a straight line it is more or less concave in a number of sj)ecies of the genera Celliilaria and Tlutldinoporella, so that the hinge-line falls a little proxi- mally to the edge, and in such cases the sim])le operculum does not fill the whole zoa^cial aperture, the proximal part of which is filled by a membrane. Within the division Ascophora the same thing appears in a new form from Singa- pore belonging to the family Petraliiilae. Jul lien' has founded a genus: Clui- perio, the species of which were formerly referred jiartly to Membrnnipora, and partly to Monoporelhi, and Waters'' says regarding this genus: This group was indicated by Jullien under the name of Chaperia, but while he based it upon two lateral plates, which I have shown are for the attachment of the oj)ercular muscles, and do not occur in all species, the important character is the form of the operculum, which is separable, and which has at each side an elongate pro- tuberance for the attachment of the muscles. « hi oi)j)Osition to Waters I would maintain that the most important generic character is the two plates mentioned, which I have found in all sjiecies I have examined, whereas the operculum according to my investigations is subject to a fairly considerable variation. As Waters refers both Meiiib. (j(ih-ala and Menib. crislata to Cli. <inniiliis Manz., we must, before speaking about the operculum in the different forms, make the ad- mission that our material is too small to venture on expressing an opinion as to the identitj' of the two last-mentioned forms, which in any case are very closely con- nected, hi a species, which under the name of Memb. cristata has been sent me by Miss Jelly and which came from South Africa, the opercular valve occupies nearly the whole of the distal half of the large oval aperture of the zooecium, and is in its proximal portion furnished within each lateral rim with a very
' 8, p. 20; '^, p. 44(i; » 43, p. 507; * 45, p. 61; ' 112, p. 655.
39
thin ami not very long sclerile sloping dislally and inwards. Tiie opercular valve as well as llie memljrane whicli occupies tlie rest of llie aperture of the zocEcium, is thin and fine and not more chilinizcd than the membrane, which covers the calcified frontal surface of llie zoci-cium. hi a new species from New Zealand, which is provided with six l)ranched spines, the opercular valve and the mem- I)rane which occupies the rest of the oval zooecial aperture, are not more chitinized than the rest of the covering membrane, but the opercular valve is at a considerable distance from the rim furnished with a continuous arched sclerite. We will call this species Ch. arcifera. While the operculum in Ch. cervicornis has a similar structure as in Cli. cristata, it shows some dilTerence in a form which under the name Memb. (jaleata, v. erecta has been sent me from the British Museum. The two sclerites are somewhat shorter here, and the opercular valve as well as the mem- brane which fills up the rest of the aperture is here somewhat more chitinized and somewhat more yellow in colour than the covering membrane, without however the limit between these portions being very sharp. The aperture of the zooecium is shorter and wider in Ch. spinosa than in the above species, and the largest part (74.or*/,)of it is taken up by the opercular valve, which is here furnished with two long and strong sclerites. The opercular valve and the membrane filling uj) the rest of the aperture form here a plate which in its stronger chitinization stands in great contrast to the covering membrane connected with it. Finally, the broad triangularly rounded aperture in Ch. Capensis is as in the other species filled by an opercular valve with two strong and short sclerites and a supple- mentary membrane, but both are here fused together into a strongly chitinized plate.
It is evident from the foregoing comparison that the portion which has been named by authors »the operculum ^ in Ch. spinosa and Ch. cdpciisis, not only corresponds to the simple operculum in a CeUiilaria, Microporn, etc., but also with an adjoining portion of the original membranous cover. These two portions are here fused together to a chitinous plate, of which only the distal portion, which has a free rim and is connected with the vestibulum, can emerge from the zooecium. Further, a consideration of the shape of such an operculum will alone be sufficient lo come to this result, for since the hinge-line must be in a straight line, it is evident that an operculum which has an arched proximal rim cannot emerge from the zoa>cium at its j)roximal portion. An operculum like that here mentioned we may call a compound operculums understanding therewith an oper- cular formation in which the opercular valve is fused together with an adjoining portion of the original membranous cover to form a single, more or less strongly chitinized plate, in which we can distinguish between the valvidar portion and
40
the accessory portion. Within the division Anaska such a compound opercuhim appears not only in the mentioned Chaperia species hut also in Megapora ringens and Foveolaria eUiptica (PI. VII} fig. 7 h), hut in these two species with the peculiar modification, that the valvular portion and the accessory portion are here con- nected by a low linear belt of thinner material in their whole breadth.
Besides in the members mentioned of the division Anaska a compound operculum appears in most members of the division Ascophora, and it may here be charac- terized as a double operculum, as it really has a double function. While the accessory portion of the operculum, which is placed proximally to the hinge-line in Ihe Anaska forms mentioned, is connected with the covering membrane of the zoo'cium, it is continuous with the basal or inner wall of the comjjensation-sac in the Ascophora, while the frontal wall of this sac is connected with either the distal rim of the covering membrane (in the forms which possess a Cryptocyst), or (where such is lacking) with the distal rim of the calcified frontal wall (Hippo- thoidae and Catenariidae). This was already shown by Jul lien', who calls attention to the fact that the hinge-line of the operculum does not coincide with the proximal rim of the operculum, but lies more distally, while the opening which leads into the compensation-sac is placed immediately proximally to the operculum. When the valvular portion of such a compound operculum emerges from the zou'cium, the accessory portion will on the other hand go down into it and thus open the compensation-sac, to which it serves as operculum. In all such ca.ses where an operculum ends in a proximal convex rim or a rim furnished with a projecting median portion, as for instance in all the species referred to the genera Lepralia and Schizoporella, it is evident that we have to deal with a compound operculum, as a simple operculum must always end in a proximally straight or concave edge. On the other hand, the presence of such an edge does not exclude the possibility, that the operculum may be compound, and the only certain way to settle the question is to find the hinge-line of the operculum. An articulation similar to that which lakes place between the valvular portion of the operculum and the accessory portion in Megapora ringens and Foveolaria clliplica occurs within the division Ascophora in the genus Arthropoma, which includes the two species A. Cecili and A. circinata, because the small proximal process of the oper- culum is connected in a similar way with the valvular portion of the operculum.
We have already under the compensation-sac discussed the well-known fact, that a series of forms have a median pore, placed at a greater or less distance from the zooecial aperture, which leads into the cavity of the zooecium. II has
' 45 a.
41
been proved for some of these forms Ihal the compensation-sac opens out through this pore and there is hardly any leason lo doul)l, that this applies to all. Most of them have a sini])le operculum, and a compound operculum is only found in species of tlie genera Onchoporclla and CalweUia (PI. XIII).
Just as a sim{)le operculum may either be quite chitinized or only separated from the covering membrane by a basal sclerile, a compound operculum may also be formed in these two ways. While for instance we have a completely chitinized operculum in the genera Schizoporella, Eschariiui, Microporella, Myriozonni as also in certain Cluiperia species, the compound operculum in other forms is membra- nous or very slightly chitinized and only separated from the basal wall of the compensation-sac by a basal sclerite. This is the case for example with the oper- culum in Enriislnnielld fornminiriera, Hippopodina fegeensis, Cheihpora sincera, Smittina porifera, in numerous species of the genus Holoporella and in all mem- bers of the family Onchoporidae. In most species of the genera Escharella and Ksclmroides, in all species of the genus Discopora and in a number of species within the genera Smittina, Holoporella and Petralia the aperture is covered up by a membranous operculum, the distal part of which is formed by an oper- cular valve, while the proximal portion goes immediately over into the compen- sation-sac.
The connection between the operculum and the zooecial aperture in the Cheilostomata may take place in two different ways, which in a few instances are used at the same time, namely partly by direct connection between the proximal edges of the aperture and of the operculum, and partly by a connec- tion of very slight extent which occurs at each end of the hinge-line. The first mode of connection is found in all the Anaska. and in those Ascophora in which the compensation-sac oj)ens out through a median pore separated from the aper- ture of the zooecium. The simultaneous occurrence of both modes of connection is found in a number of acanthostegous and coilostegous forms, for instance in Fi<inlina fupdaris, as well as in the genera Tlialamoporella and Stenanoporella (PI. V), and in the last mentioned genus, the species of which have an usually large and, owing to its chitinous armature, heavy operculum, this last connection is very firm, the tip of the strong and conical hinge-teeth being connected by a rather long and cylindrical chitinous band with the proximal corners of the strong opercular arch.
In all Ascophora, the compensation-sac of which opens out through a part of the aperture which can be closed by the proximal or accessory portion of the operculum, the operculum is only in firm connection with the aperture on each side of the hinge-line, and in most forms which have a well-developed opercular
42
arch, a similar connection taiies place helwcen thisaiul llie ajierlure as that found in the genus Stegnnnpnrella-
We may mention Emlmllothecn qnailidta (PI. XX, lij^. 11 a), Euthiiris cl(itlirala\ Calpidium nrnatiim (PI. XVIII, fig. 13 b), ^>Lepralia-^ restita and Ptcrocella nlcita (PI. XXI, fig. 4 a) as examples of species with large and strong hinge-teeth while on the other hand tlic hinge-teeth are quite lacking e. g. in species of the genera Discoporci and Eschaioiiles. hi the forms which have no opercular arch at all, or in those with an imperfectly developed one, the connection lakes place either on the very margin of the operculum or within this, and the first of these cases we find in the genus Porella. hi P. struma for instance we find in each of the proximal corners an elongated thickening, which forms almost a right angle with the muscular ridge and which is in connection with the aperture. In Mijriuzoum Inincatiiin on the other hand the proximal part of the operculum is on the inner surface surrounded with a strong marginal thickening and in the distal part of this on each side is found a rather large oval pit into which a rounded hinge- tooth is immersed.
The aperture, besides being furnished with hinge-teeth may have other protub- erances or teeth, and of these we may now mention some which from (heir position must be supposed to support the operculum, or to counteract an ex- ternal pressure on the latter. Such formations, which have their place either within the proximal or within the distal rim of the operculum, may appear sometimes in pairs, sometimes as a single, low plate, and are found in forms which have a simple operculum (Celhilaria, Microporella, Micropora), partly in forms, the aperture of which has a small but sharply marked sinus (Arthropoma, Escharimi. Schizopordla). In the Celhilaria species, where in a smaller number of cases they may be found both within the proximal and the distal rim, they most frequently appear as small, paired, rounded or conical teeth, which may occasionally be long, like canine teeth, as in C. rujida (PI. VIII, fig. 1 a), where they appear both proximally and distally. In a few species such a pair of teeth is replaced by an unpaired low plate, which is proximal in C. aiujiistilolnr , distal in C. CharlesworthiiK In the species of the genus Microporella (PI. XV), Nve gene- rally find in the whole breadth of the proximal margin a more or less devel- oped supporting beam, sometimes with two small conical teeth, and such is also found in Micropora centralis (PI. VII, fig. 1 a). To the same sort of foim- ations as those just mentioned we must probably also class the curved and pointed tooth, which is placed on each lateral rim of the aperture within the
' 19, PI. XVI, fig. 20-'21. ' X I'l- III, fig. 16^^ » 7, PI. X, lig. 4 a.
7fc
43
operculum in Pelrnlid pornsa, Pel. /'uZ/ur and in a new species from Singapore. These teeth, which without closer examination would be regarded as hinge-teeth, have really nothing to do with the suspension of the operculum, which takes place distally to them.
While these teeth all have their place on the inside of the operculum we also on the outside find unpaired as well as paired ones. A median tooth is found as is known in numerous species within the genera Esclmrellu (PI. XVII), Escharoides (PI. XVII), Exocbella (PI. XVII), Smiltina (PI. XVIIl, fig. 12 a), Dis- copora etc. and its frequent presence in species which have a membranous or slightly chitinized operculum, shows that it must be regarded as a protective formation. Lateral teeth appear on the peristome in certain species of the genus Escharoides (PI. XVII), besides in the species of the genus Exochella (PI. XVII), and Jullien' considers these teeth in Ex. Umtjirosiris (PI. XVII, figs. 9a, 9c) to correspond with the hinge-teeth in Sinittind, although they can grow together with the median tooth.
We have already called attention to the fact, that the occlusor muscles are most often fastened to the opercular arch, where such is in any way well-devel- oped, and they are then as a rule fastened to the apex of a more or less devel- oped triangular lateral portion, well-developed in Euthyris clathrata, but only slightly indicated in the low, but strongly chitinized opercular arch in the Steyanoporella species, which is often placed a good way within the free margin of the operculum. Where the opercular arch is wanting, or only slightly devel- oped the occlusor musics are as a rule fastened to the inner surface itself of the operculum, and we can here again distinguish between two cases, according as they are fastened to special ridge-shaped protuberances or to a pair of small, pit-like spots, which Waters has called >>muscular dots«. Such muscular dots can for instance be found in the genera Cellepora, Lekythopora, Avthroponvt. Con- escluirelliiui and Schizoporella (PI. XVIII, figs. 3 e, 4 c, d), while muscular ridges appear in the genera Porella, Eschdiina (PI. XVIII, fig. 2 c) and TubrndUirui.
We must finally remark - upon the fact that the operculum in a number of Coilostegous forms consists of two layers, namely an external membrane, which forms a continuation of the covering membrane of the frontal wall, and an inter- nal chitinized or calcified layer, which we must regard as the operculum's crypto- cyst. Such an operculum with two layers is found, besides in the species of the genus Celhdaria, in Microporina borecdis, Micropord coriacea. M. Sormani n. sp. (PI. VIII, figs. 3 a, 3 b), M. perfondci, as also in a species described in this work which I have identified with Macrupora centralis Mac Gill. (PI. VII, figs. 1 a, 1 d). In the last
' 45, p. ,^5.
44
as well as in Micioponi Xoriwmi (PI. VIM, fig. 3 b) the deeper layer of the oper- culum is calcified and has quite the same appearance as the cryptocyst of the frontal wall. In a figure drawn by Calvel', representing a longitudinal section through Celliilaria fistnlosa, it is seen very plainly, that the two layers of the oper- culum meet in the distal and the proximal rim, l)ut that they are also separated by a space.
Within the division Ascoplwra an operculum with two layers has hitherto only been found in the interesting species Eiithijris cldlhrctta Harmer. It consists of two chitinized layers which are fused together along the proximal rim of the accessory portion of the operculum and in a median part connected with this, but otherwise they are separated by a distinct space.
We cannot leave this section without touching upon the terminology used for the description of the opening in the zoa-cium which is covered by the oper- culum and by the frontal membrane. While Johnston'- generally uses the word ♦aperture* not only for that portion of the zoo'cium which is covered by the frontal membrane in the Malocnstega, but also for the opening which is covered by the operculum in the Coiloslega and Ascopora, Busk' in his catalogue only uses this name for the zocecial opening in the Malacostega and the word »mouth« for the opening which is closed by the operculum in the Coilostega and Ascophora. Hi neks* consistently maintains a similar distinction, using however the word »orifice« instead of »mouth«, and he also indicates by this the opening covered by the opercular valve in the frontal membrane of the Malacostega. In his general review of the genus Membranipora he makes the following statement: >The terminology employed in describing the members of this genus requires a word of explanation. The area is the portion of the cell surrounded by the raised margins. The aperture is that part of it which is not closed by a calcareous wall; and on this is placed the true orifice — a semicircular opening, with a valvular operculum*. Apart from a few inconsistencies Busk follows Hincks' terminology in his work on the Bnjozoa of the 'Challenger* Expedition; while Waters in his numerous works describes the opening which is covered by the operculum as an »oral aperture*, or simply as »aperture«, and he also uses the latter for the zooecial opening in the Membranipora. Finally, Mac Gillivray'' in a work on the tertiary Bryozoa of Victoria has felt himself obliged to replace Hincks' term »orifice« with a new term »thyrostome«, concerning which he writes: »The nomenclature is thai in general use. The only innovation of any consequence I have made is the introduction of the term »thyrostome« (Ovga aiofia) for the
' 9, PI. VI, fig. 11. ■' 41 a. '2. ■• 22. ^ J< p. 2.
7fc
45
opening through which the tentacles and oral extremity of the polypide are protruded. The terms orifice, oral aperture and mouth are inaccurate and con- fusing and the proposed name will I think prove ad\antageous«.
It is evident from the above morphological considerations on the operculum, that when we exclude the small number of species which are furnished with a simple operculum, we have in all other Cheilostomatous Brijozoa, on the frontal side of the zocecium, a larger or smaller opening (viz. an uncalcified portion) which is covered by an operculum in connection with a larger or smaller portion of the original frontal membrane. The relation between this portion and the opercular valve may be very different both in regard to the mutual size of the two portions and to their nature. In the Malacostega both are generally mem- branous and the opercular valve is as a rule many times smaller than the rest of the cover. We lind a comj)letely chitinized opercular valve however in a number of Onijchocelhi species (PI. XXII, fig. 3 b), as well as in a number of species of the family Scrupocellariidae, and in quite a number of Meinbranipora forms the suplementary cover is greatly reduced in extent. This is for instance the case in Callopoia luina.v, C. trifolium, certain varieties of C. Fleniincji, Kosscliaiui Rosseli and Membvaniporina artjentea Mac Gill. ', in the last of which it may be smaller than the opercular valve. In the Ascophora the suplementary cover, or as we before have called it the accessory portion, is frequently fused together with the oper- cular valve to a well chitinized, compound operculum, but in quite a number of forms (e. g. in Discopora species, certain l'^sch<tn>idcs species, etc.) the structure of the operculum is not different from that we find in the Malacosleija, because the opercular valve as well as the suplementary cover is membranous. On the other hand we find in a smaller number of Malacoslega a well-chitinized, compound operculum, as in Cluiperia s])in()S(i, Cli. aipensis and Me<]upor(i rintjens, and 1 do not doubt that ^LepruUct^ Poissoni and Dorij/xtrella spathiilifera', both of which have a well-chitinized, compound operculum, must also be classed with the division Mdlctcoslec/a.
For these reasons we propose to keep the term > aperture «. which Johnston uses, for the frontal zoreciai opening in all Cheilostonutta; for, even though it might be right to use a special term for the o[)ening covered by a simple operculum, two separate terms would i)e unpractical, as the forms provided with a simple operculum occur as a rule in families together with forms which have a compound operculum. It can always be settled, by examination of the form of the oper- culum and the aperture, the position of the hinge-teeth ami ol the corresponding
' 74. vol. T, PI. SI, fig. 2 - 84, p. lOfi.
46
parts of the operculum, which part of the aperture corresponds to the opercular valve, and if we require a special expression for this we may call this »the valvular aperture-.
Polymorphism in the Bryozoa.
As is known polymorphism also occurs in the ISriiozoa, but in contrast to the case in the Hydroid polyps it is not present in all species, even not in all genera or families. We can distinguish between four main forms of individuals (Bryozooids):
Aiito:oa'cia (Auiozooids), which contain a polypidc, consisting of a tentacular apparatus and a well-developed digestive canal.
Heterozowcia (Heterozooids), which have no intestinal canal, and at most have a trace of a polypide in a small cell-body, furnished with a circle of fine bristles. The chamber contains a strong muscular apparatus for moving the operculum, which sometimes only covers the aperture, in which case the Heterozooecium is called an Avicularium, and sometimes extends beyond this in the form of a whip, as in the so called vibraculum, but otherwise there is no sharp limit between these two forms of heterozooecia.
Kennzoa'cia (Kenozooids), which not only have no polypide, but as a rule no aperture and always no operculum. While the Autozoo^cia might be regarded as alimentary individuals, the Heterozooecia as defence individuals, the Kenozoojcia must be regarded as supporting, fastening and connecting individuals. To this class of individuals belong: the segments which compose the thread-like basal parts in numerous CJenostomala, in the Cyclostome genus Crisia, and a smaller number of Cheilosionmtn (Hiiskia, Alijsidium etc.), the segments which form the upright stems in Slirparia, Ahjsidiiim and CIdidonia, and certain portions of the branches of the last, the radical fibres and the chambers for the insertion of the radical fibres in Scnipocellariidae, Caleiuiriidae etc., the peculiar lateral compartments in the Catenariidae, the modified marginal individuals, which appear for in- stance in Flustra securifrons and Fl. carbasea, the small chambers which form the encrusting base and the outer (ba.sal) layer of the Reteporn colonies, the peculiar cavities which appear among the zocecia in Membranipnra Lucroi.vi, Cribrilina Udimnryinata etc., the supporting tubes in the Cijclostonudd, as also the small chambers which surround the oa-cia in the family llippollwldae, in nuuiy species of the family Cateiutriitlae etc. (see under ooecia).
As a fourth class of colonial individuals we may perhaps in many species regard the egg-producing individuals (Gonozmn-ia). While in numy cases, e. g. in Meiubniniponi meinbraiiuceu, all individuals in the colony seem able lo produce
47
eggs, this function in otiier forms is in charge of special individuals, which may often differ greatly from the ordinary zooecia (Adeonidae, Catenariidae, certain Hippothoa species), and which occasionally have no polypide (Hippothoa /iy«/i/ia). They are in most cases furnished with separate marsupial clianihers, the so- called oci'cia.
I may now make some mainly comparative observations on the structure of the Heterozocrcia. It we look at the frontal surface of an avicuiarium, the oper- culum (or mandible) of which has been removed, we find that a greater or lesser part of this surface is occupied by an aperture covered by a membrane, within which there is often found a more or less developed cryptocyst. This part corre- sponds with the membranous area in the zooecia of a Meinhninipora, but while such an area in the zocrcia is only found in the division Mulacostega, it is found in the avicularian chamjjer in all Cbeilostoniatous Bnjozoa. We may further discern between two different parts of this area, a distal, the opercular area, which is covered by the operculum and a proximal, the subopercular area, and the border between the two areas is formed by the hinge-line, which coincides with the proximal edge of the operculum. This border is in all Ascopbora with the exception of the Adeonidae and of Leicschava criistacen also indicated by a calcareous cross-bar, arising from the prolongation and amalgamation of the two hinge-teeth, and besides in the genera Nellia, Finiilina, Arachnopnsia, Miciopura, Microporina and a few Meinbraniporina (e. g. in M. crassiinaryinfdd) species, in which such a cross-bar is also present, the two hinge-teeth are separated in all other Anaska. Waters has already called attention to this difference.
The cryptocyst, which can be present both in the opercular and the sub- opercular area reaches its highest development in the heterozoa>cia of the genera Onychocelld ' and RluKjasostomii, the former of which is mainly and the latter exclusively represented by extinct species. The cryptocyst is here, as in certain fossil species, which for the present I refer to the genus Aspidostoma (PI. VI c, figs. 3 a, 4 a), extended over tbe greater part of the frontal wall of the chamber and is only provided with a small opening of varying shape, which is intersected by the hinge-line of the operculum and through which the muscles make their way out to the operculum or mandible. In the avicularia of Fliistra foliacea the cryptocyst extends over most of the subopercular area and something similar takes place in the avicularia in several Thalamoporella species (Fl. VI a). A well- developed cryptocyst is also found in the opercular area of the large avicularia in Flustnt (dujssicola as well as in that of the large lyriform or spoon-shaped
.S(), PI. 07.'), ligs. 2, 15.
48
avicularia which occur in ThalamoporelUi lioticho (PI. VI), Thai, novae boUandiae (PI. VI a), Cribrilina fiyiilaris etc. On the other hand, a cryptocyst is quite lacking in the heterozooecia in the families liicellariulae, Scnipocellariidae, Catena- riidae etc.
On account of the free movement recjuired by the operculum (mandible) of the heterozod'cia, this is always simple (pag. ;?S), and naturally ends in a straight proximal edge. While the basal and frontal wall of the vestibulum in an ordinary zooecium are connected by two free lateral walls, which on the closing of the operculum are folded, the latter are absent in a helerozooecium, and the vestibulum is consequently here developed in the shape of two separate laminje of which the basal takes up the opercular area, while the frontal, which proximally is joined to the basal, extends over the internal surface of the mandible. We saw above that in an ordinary zooecium the frontal wall of the vestibulum may sometimes be attached to the edge of the operculum, sometimes at a greater or smaller distance within this. This is also the case with the helerozoa»cium, only that the variation is still greater here. While for example the frontal lamina of the vestibulum is attached to the edge of the mandible itself in the small avicularia with a semicircular mandible, which is found in most species of Fhistra, Porella, etc., in the large avicularia of Flnstra abi/ssicola (PI. XIX, fig. 13 a) it is only attached to a triangular median belt, which decreases in breadth distally and does not reach right out to the tip of the mandible and the latter is thus provided with two wing-shaped latei-al parts. In the Onychocella species (PI. XXII, fig. 3d) the frontal lamina is only attached to the proximal part of the mandible over a small triangular area, and still further proximally the attach- ment takes place in the llagelliim of the real vibraculum. As the vestibulum in the heterozooecium as already stated consists of two separate laminae and does not, as in the zooecium, form a funnel-shaped tube, the frontal lamina^ comes into closer relation to the mandible, and for that reason the latter obtains the charac- ter of a two-layered plate, which between its two layers encloses a .space, the mandibular cavity (PI. XIX, 10 b, 13 a, 14 a, 15 a, 15 b), corresponding to the opercular cavity. While the mandible itself is always more or less strongly chitinized and as a rule provided with a rounded spot of thinner nature (the so called »lucida«), near its proximal portion the vestibular covering of the man- dible may sometimes be perfectly membranous, sometimes more or less strongly chitinized over a larger or smaller portion of its surface. It seems thus to be completely membranous in the large avicularia found in a number of Cellepora species, while we very often find in the small avicularia with a semicircular mandible, which so frequently appear in b'liislru, Purella and Cellepora, a dis-
49
tiiicHy chitinized marginal region, which consequently conesponils to llie previously mentioned opercular arch. There is also a distinct contrast between the marginal region and the median region of the vestibular layer in the above-mentioned avicularian mandibles of Fliistra (ihiissicohi and Onijchocella sp (PI. XXII, fig. 3 d), because the marginal portion, which forms the lateral walls in the mandibular cavity is strongly chitinized and shines through the surface of the mandible as two brown ribs converging towards the apex. In the elongated pointed mandibles of Fliislra denticiilata, Microporelht imirtjimita, Schizoporella lonyirostris and Scnti- cella iilagiostoiua the vestibular layer is chitinized over the greater part of the length of the mandible, although at the proximal part of the mandible it changes to a softer part, and a longitudinal section through such a mandible (PI. XIX, fig. 10 b) shows that the inner cavity towards the apex of the mandible dwindles to a very fine canal; this seems to suggest that the narrow solid tip is formed l)y a fusion of the two layers. It is not always, however, that such translucent lines arise from the vestibular layer, as many mandibles may be provided with two distally converging ridge-shaped thickenings which, like the ridges mentioned under the zocEcial operculum, are projections from the inner surface of the mandible itself. Such converging ridges are found in the mandibles in most species of Porella, in Discopora, etc.
Time does not permit us to enter into further details liere regarding the muscles of the avicularia, and we may just recall that for the movement of the mandible there are abductors or openers, and adductors or closing muscles. While the lirst are always double, Ihe latter are sometimes single, sometimes double, and in many cases two separated muscles are attached to the mandible by a single tendon. More rarely we also find parietal muscles (Fliislnt species, Fscluiroiiles coccinea).
Waters, as is known, has shown that the cavities provided with an elongated triinigular opening in the extinct Eleidae, which were formerly taken to be oircia, must in reality have been avicularia-like formations; they dill'er however from the cheilostomatous avicularia, in always lacking a membranous suboper- cular area. In a number of these species I have found a calcified mandible.
Ooecia.
Before giving a comparative account of the structure of the oa-cia, we may summarise what the literature and especially the older contains regarding these formations. The first writer where we have been able to find anything about the
4
50
ooecia, is John Ellis', who in his well-known work on the Corallines not only treats of the hydroid polyps, coral algae, varions Oclacliniae, sponges etc., hnt also of a number of Unjozoa. hi a number of species of the genera Buyiila, liicclUiria and Scriipocellaria he has noticed and figured the ooecia, which he terms « Malls, testaceous Spherules', or »testaceous Figures* '; but while he recognised, although in an imperfect way, the importance of the gonothecae for the reproduction of the hydroids polyps" (»I discovered that they were Matrices or Habitations of young Polyi)es, which are produced here and there, on the Sides of the Parent, as in the Freshwater Polype*), he does not seem to have reached to a similar comprehension of the ooecia. He only speaks in detail about the owcia of a tropi- cal Bmjula species, R. neritiiia ' and expresses here the very remarkable view that they are a sort of small snails, from the eggs of which the colony originates: »I plainlj' discovered it to be the connected Niduses or Matrices of certain testa- ceous Animals, like small snails or Neritae* . . . »()r let us suppose, that the testaceous Animal . . . lays its eggs; these turn into vermicular-shaped Polypes, whicli, after they have fixed themselves to some marine Substance, rise up, and push forth into branches of small Polypes in their Cells«. The oa'cia are thus figured on the accompanying drawings as small .S/j/ror/i/.s- or PUiiiorbis, and from this description Linne gave to this species the name »nerj7i/ia«. Ellis expresses elsewhere a supposition that a similar relation obtains between certain Bripzoa and Bivalves: »The next class, which is the Esclutra deserves our notice» . . . »There appears a great probability of some of these being the Matrices or ovaries of certain Species of Shellfish, perhaps of the Bivalve Kind^ On Flnstra (Eschara) foliacea he further writes"": »Upon examining some specimens lately, I discovered at the Entrance of many of the Cells a small testaceous 13o(ly, like a bivalve Shell «. As appears from the figure to which the writer refers, there is no oa'cium whatever but an oj)en zoa-cial aperture, in which consequently the orifice itself represents the one, the operculum the other sheU.
Pallas'' suggests the view that the ooecia are ovaries, a view retained to the time of Huxley. It was however chiefly the oa>cia in the incrusting forms (»£sc/ior««), which he was disj)osed to regard in this way, whereas on the other hand he is more doubtful on the question, whether the free plant-like forms ('('.ellahirid ) are provided with such. In iilurimarum, presertim lapidescenlium Eschararnm anli(iuioribus cruslis passim, ad singiilarum cellularum oscula, ohser- vari solet bulla galeae instar cellulae ostio imminens, substantiae Escharae homo-
' I'J, p. ;!:)— .19. •- 12. Introtiiu-tidii p. IX. ' 12, p. 35. ' 12, liitioduclioii p. XV '■' 12, p. 71.
pi. XXIX, K. "91, p. :»;.
51
genea & continua. Vascula sen Galericulae in Cellulariis staliin considerandae, subanalogae; has in Eseharis bullas ovaria forte esse suspicionem injiciuiit'. It is very intelligible that the free, prominent, somewhat stalked (xrcia in Ihujiila and Bicellarut would make a dilTerent impression on an observer than the od'cia in the incrusting forms. Also, Ihey appear sometimes (in liiiijiild nerUind and Bicellaria ciliata) not on the top of the zooeciiim but fixed to (he one side. In that case they correspond in their position as well as in their equipment with a stalk-like portion with the ^bird's head« avicularia in Bugiila and Bicelliiriu, and Pallas considers them therefore as organs of related nature. His above-quoted view, in which he terms these ditferent stalked formations as organs somewhat related (subanalogae) to the otrcia in Escluira is further explained in another place', where he suggests that they are of service in fertilisation (seminilicationi). On account of the resemblance to the gonothecae in the hydroid polyps he is disposed to consider the gonozooecia in Crisia as ovaries'. Ovariorum qvae in Sertulariis videbimus similes vesiculas in sola C. (Crisia) eburnea & falcata obser- vatores invenerunt. An aliis qvo(}ve speciebus contigerint incertum. Reperti vero in C. neritina & avicularia Galericuli sen Calyculi singulares, in recenti stirpe spontaneo motu priediti, singulisque cellulis adpositi, qvorum certus usus hucus- qve nos latet, seminilicationi in his speciebus destinata organa fortassis esse repe- rienlur«. It is evident from what he says further: ^Lateralis inspectio .. . docet, bullulas istas esse galericulis s. neclariis caput aviculae referentibus, in G. avi- cularia, analoga organa'"', that he considers the ooecia in BiujnUt neritina as or- gans of a similar nature as the 'bird's head« avicularia. This view, that the ooecia and the avicularia are related formations we tind again in several later writers, and with regard to the designation »Nectarium which Pallas often uses for the .stalked otecia and avicularia, we find an explanation in Ellis and Solander's work.
In this work, published by Ellis' daughter after the death of the writers', it is said regarding Flnstra: The ovaries appear to be the pearl-like studs, which we find at the tops of the cellss and regarding >(>//(/;•;>(.: »lhe ovaries are uncertain, but most probably the little hemispherical covers, thai appear over the cells, do that officer. Ellis returns here again to the od-cia in /)'»</. neritin<t: In my observations on this genus I cannot pass over the singularity of the Celiaria neritina, or Snail-bearing Coralline. The likeness to Nerits of its rows of little round adhering bodies, which are open on one side, together with their shell-like figure . . . inclined me to believe at first thai they were the young
' <.ii, p. (>(). ■■ ill. p. i;s. •' i:i, pp- 11. 10— 20, •-'ii.
52
ones of .such ;i small kind of slicll-lish. Hut l>y c-ouipaiing tluMii willi liic figures of others of this genus, they appear rather to he what we have called Ovaries. Or pcvhaps they arc young of the animal dclcnded by a testaceous covering like a little shcU-lish, which at tiic time of its maturity separates from its umbilical
cord IVom whence it drops and soon adheres to a pro])er substance as a
base, beginning to form a Coralline like the parent animal.- There is discussed here also another peculiar view regarding the oa'cia and the avicularia, both having been considered as nectaries: »A later writer, who is a strong advocate for the vegetation of Zoophytes, supposes these little pearl-like figures as also those like the heads of birds in the Birds-head (Coralline (or OUaria avicularis) to be their Nectariums, analogous to what is so called in the flowers of some plants."
Lamouroux' also mentions the oa-cia in li. neritiiui, and introduces us to several hypotheses regarding the functions of these formations. On les a con- siderees comme des opercules que le polype construit a voionte, soil pour se metlre a I'abri du choc des corps exterieurs, soil i)our liiverner, soit encore pour fermer sa demeure lorsqu'il a cessc de vivre. II est probable qu'aucune de ces hypotheses n'approche de la verite, et je pense que ce sent des ovaires renfermant les germes de nouveaux individus; j'ai observe (jue ces corps vesiculaires sont quekjue-fois tres-entiers, et dans ce cas je les ai toujours vus remplis de petits corps globuleux; il parait que ces ovaires s'ouvrent par une fente transversale; toutes les Ibis i|u'elle existe, les ovaires sont vides.
Milne Edwards- considers tlie oa'cia in F.schdid as well as the avicularia on the zooecia as "vesicules gemnnferes«, or »capsules gemniiferes«. »Les obser- vations de Loefling et de i)lusieurs autres naluralistes nous out a|)|)ris cpie ces vesicules (ofpcia) sont des capsules gemmiferes, el par eonseepient nous sommes porte a croire (|uil doit en etre de meme ici, et que le tubercule pyrifornie, dont nous venous de decrire les divers etats (the avicularia in E. sulcata) doit etre considere comme elant un receijlacle conlenant les gemmules et servant a leui- livrer passage.
Lamarck' also uses the name »vesicula' gemmilei;e , but just as oflcn the name ovaria for the oa^cia as well as for the gonothecie in the hydroid |)olyps. The same doubt, which Pallas had, as to whether the free, plant-like forms (Cellaria) possess such formations, is repeated here: '>Vesicula; gemmiferu' nulla', nisi bullic qv;e in nonnullis speciebus extant.
lieid' studied living specimens of BiujiiUi (iniciildria with eggs in the oti'cia.
' .'I'j. p. l.-ili— 134; -■ 77, p. 48: ' .'.1. ji. 174: ' <).->.
53
Nevertheless we can only understand his view of the striichne ol' the od-iiiini, and of the relation of the eggs to it, after reading Nitsehe's later but fuller description of the oa'cium in BiceUaiia ciliaUt, which is built in a similar wav.
Busk' introduces the name »ovicells«, which is still used by some writers, for the here discussed formations, but the older view of Ihem as capsules, con- taining the ovaries, was first altered by Huxley's": Note on the reproductory organs of the Cheilostome Polyzoa.« He pro])oses here the now prevailing view of the ocTcium as marsupial chambers, into which the eggs arc brought from the zon-cium to develop into larvaj. He found namely in Hiignla aniciihirid, that the egg is formed in the zoa^cium where it is attached to the funiculus near the stomach and also that the originally empty oa'cium at a certain time was seen to contain an egg, which was more developed than the one observed on the funi- culus, and which after cleavage became an embryo provided with cilia.
Against Huxley's view Hincks' maintains, that the eggs from which the ciliated embryos are developed according to his investigations are formed in the oa-cia (ovicells) of a shapeless, grained mass. As to the eggs which Huxley found in the zooecia Hi neks states that they are most common in zoo^cia, the occcia of which have emptied their contents, and they can even be found in zou'cia, the polypide of which are dead, from which it must be concluded that they are only set free on the dissolution of the soft content of the zooccium. They are never ciliated at any stage of their development.
The first detailed account of an otrcium is given by Nitsche*, who describes the development and structure of the ooecia in Bicellniia ciliata. He represents it as formed of two hollow, two-layered, bladder-shaped outgrowths from the margin of the zoa-cium; the smaller, which is membranous, is grown over by the larger, the outer wall of which is calcified, and which in the full-grown condition forms a helmet-shaped body connected by a short stalked portion with the zooecium. The membranous bladder serves as an operculum for the helmet-shaped portion, and its interior is penetrated by a muscular chord, by the contraction of which its rim withdraws from the edge of the oa'cium so that the larvie can get out. hi the above-meulioned work of Re id attention had already been called to the fact that this membranous operculum of the ooecia in Biigula ciniciihtrid. which contains larva\ undergoes rhythmical contractions (This membrane was observed in a few instances where the ova were fully formed to contract and relax at intervals, and in this way it may assist in the escape of the ovum«. Without knowing Huxley's observations Nitsche arrived at the same result with regard
'3; ^ S9, » 37; ' 7i).
54
to the fuiH'lion of the ocecia. He has seen the formation of the egg in the zocecinm and while the ooecium originally was empty he found it at a certain lime containing an egg, without heing able to ascertain how it came there. He expresses the following supposition: »wahrscheinlich zwangt sich das Ei durch den hohlen Stiel der Ovicelle und tritt durch eine OefFnung, welche ich an der Stelle, wo die beiden Blasen zusanimenhangen, gelegcn vernuillie, in den Raum zwischen den beiden Blasen." Nitsche tries to explain Hincks' different view, that the eggs are formed by a granular mass in the ooecium in the following way, that the egg after its transference to the ooecium instead of developing further, sometimes dies away and dissolves into a shapeless mass. Finally, he states that the supposed eggs, wliich Hincks has observed in zocccia without polypide, are only peculiar bodies which liave arisen from a retrogressive metamorphosis of the polypide.
In ^Contributions to the liistory of the Polyzoa«, where Hincks* introduces the new name »o(rcium«, he admits the correctness of Nitsche's assertion, fliat the supposed eggs, which he had discussed earlier, are really the so-called » brown bodies<s and he assents to Huxley's view of the ociccia as marsupial chambers. He adheres liowever to the idea, that eggs can now and then be formed in I he ocecia and maintains the correctness of the observations which he fornierly made on this subject in a few Biigiila species and Bicellaria ciliata. In his later published, principal work- he definitely expresses the view that the ooecium has an internal connection with the zoax'ial cavity ('>its interior is in direct communication with the perigastric cavity«), but otherwise there is no further information on the structure of the ooecia. They are indicated as prominent*, "sul)immerse(l < and »immersed< {Fliistra, Cellaria), according as they are more or less prominent on the surface of the colonj' or hidden within this.
Vigelius-' in his investigations on Fliistra inembrnnaceo-lnincala has given a description of the structure and develo]Hncnt of the on>cia in this species. While the oa'cium and its operculum in BicclUirid ciluita arise as two outpushings from the frontal wall of the zooecium, the ooecium in this species arises as an inva- gination from this wall, a short way dislally to the operculum and it thus conies to protrude into the zoa'cium as a hollow bladder, the interior part of which enters into connection with the distal wall of the zooecium, which is here formed in a peculiar way. It consists namely of a horizontal, under part, which oi'igi- nally reaches right to the frontal wail of the zoa'cium and of a distally and slightly basally inclined part, which grows together with the ooecial bladder.
» 38; « 22; ' 105, p.
55
Laler the horizontal part of the distal wall and the rronlal wall of the zod'cium separate from one another. While the distal half of the oa^cial bladder calcifies, the proximal half continues to be membranous, and Vigelius thinks that the egg passes along from the interior of the zoa>cium upwards towards the otrcium between the distal wall and the frontal wall of the zooecium by which action it i)ushes the membranous part of the ocecial bladder in front of it; he thinks that this membranous part is later reabsorbed, which enables fertilisation of the egg to take place through the aperture of the oa>ciuni. The portion of the frontal wall of the zooecium, which is situated between the operculum and the free edge of the ooecium, acts as operculum for the ooecium. This operculum is provided with two muscular bundles, which reach from its free edge to the basal wall of the zoa^cium and which by their contraction are able to draw it inwards.
The present writer" in three papers, the last of which is a preliminary note has given a series of investigations on the oa'cia and has shown there, that with the exception of oa-cia, which are covered by kenozooecia, the oa»cia have no such inner connection with the zooecium as Huxley, Nitsche, Hincks and other writers have supposed. In all other cases therefore the egg must pass into the ott'cium through the outer opening of this marsui)iuni. In the last paper the author has set up eight different types of oa'cia, two of which (the epistomial and the mesotoichal) in the present work are classed under the hyperstomial.
In an important memoir chiefly dealing with the inner structure and with the embryology of the Cheilostomatous Bryozoa Calvet" has examined the ooecia of twenty one species belonging to the genera Biigula, Flustra, Membranipora, Micro- porella. Chorb.npora, Schiznporella. Lepralia, Uiubonula, Retepora and (k'Hepora. With the exception of ^Lepralid Pallasiana, in which he has found a membranous one- layered marsupium formed by a basal evagination of the vestibulum and of Cellarid fisliilosa he has found the oo-cium formed by two two-layered bladders, a superior more or less calcified and an inferior membranous one, the last of which is ])rovided with muscular strings destined for the opening of the ocecial cavity during the setting free of the larvae. He has not been able to find any coninuinication between the ooecium and the zocecial cavity and he therefore thinks that the egg, to get into the oa>cium, must perforate the membranous bladder. As to the ooecium of Cell, fistulosa he states that an opening exists in the wall between the oa>cium and the zoctcium.
In a very interesting paper Harmer^ has set forth the supposition, thai the ooecia may be looked upon as formed by hollow spines and he founds this view
54, p. 253. 55, p. 25 and 56, p. 11 — 18; ' !l. p. ^ 19, p. -283—284.
56
especially on the structure and development of the ooecia in Aliisuliiiin jxirasili- ciim and Euthiiroides episcopalis.
Before trying to give a division of the dilTerent forms of orrcia, I must ex[)res my regret, that the material at my disposal has not allowed me to give a fuller account of these formations, of which in many cases I have only been able to examine the calcified portions. I hoj)e, liowever, that my investigations will to a certain degree facilitate the work of the investigators who may be able to com- bine the desire to continue these studies witli favourable conditions of procuring suitable material.
Endozooecial ooecia (PI. XXIV, figs. 6 — 11).
We indicate by this name the ort'cia which are immersed in the zon^cia, gene- rally, however, in such a way that they appear more or less distinctly on the surface of these. Their main portion, the endoooecium, is formed by the zoffcium's distal wall, which in the free, frontal edge of the ooecium passes over into the much less developed ectooa'cium, together with which it forms a fold, the od'cial fold. In the majority of cases the distal wall has a short horizontal portion, provided with rosette-plates, which bends over into the helmet-shaped or cup-shaped ooecium, and it is only in species of the genus Retiflustra (PI. XXII, figs. 1), 2 a), that the basal rim of the distal wall lies higher than the free frontal edge of the ooecium.
If we only pay attention to the calcified portions, we should think that these ooecia were in internal connection willi the proximal zoa'cium, but with the exception of those oojcia, which are covered by kenozooecia, there seems really always to be a mendiranous separaling-wall between the zoo'cium and the ott'cium.
We can divide these oa'cia into lw(3 groups, according as the distal oi' the two chambers, which bound the oo'cium, is an ordinary zocecium (autozooecium), or a kenozoa'cium. Wc must also refer the oo'cia, which are enclosed in the avicularia, to this last-mentioned group.
a) Endozooecial ooecia, which are enclosed in autozooecia.
In the historical introduction we have referred to Vi gel ins' account of an oa^cium belonging to this type, namely, the ocrcium in Fliistra membranaceo- tnincald, and need only recall here that Ibis oo'cium, according to the description of that author, is formed by a bhulder-sliaped infolding of the IVontal membrane of the zoo'cium meeting the distal wall. As our Museum does not possess colonics of Ibis species with developing ooecia, but on llie other hand those of Fliistra seciirifrons, Ihe oa'cia of which have essentially the same structure, we may te.st the correctness of Vigelius' investigations by means of this species. The
57
ooecium in Flustid seciirijruns (PI. 1, figs. 5 ;i, h, c, PI. XIX, figs. 8 b — 8 n) whose inner pari may be loolved upon as a transformed distal wall, is a helmet-shaped calcified bladder, the basal portion of which issues from the short and horizontal |)ortion of the distal wall at a pointed angle, while its free, frontal edge passes immediately over into the frontal membrane of the zoa'cium, together with which it forms a fold, the od'cial fold. We may indicate the calcified bladder as the endoott'cium, while an ectooo^cium is only represented by the portion of the frontal 'membrane, which covers the distal pari of the endooo^cium. Between the operculuiu of the zoa'cium and the free rim of the ooecium we see a membranous portion chitinized at the distal edge (Pi. I, fig. 5 b), the ooecial operculum, which is connected with another membranous region, the ou'cial membrane (PI. 1, fig. 5 a. Pi. XIX, fig. 8j), which issues from the basal wall of the endooa-cium and forms a complete separaling-wall across the oa-cium. While this was originally situated close to the roof of the oa-cium, in an egg-bearing oa'cium it inclines the opposite way, so that it forms the fioor of the ooecial chamber (PI. 1, fig. 5 a, fig. 2 a). In the angle between the owcial operculum and the ooecial membrane is attached a muscular chord which originates from the basal wall of the zooecium, and when it contracts, the oa-cial operculum is drawn inwards and thereby permits the larva to escape. Finally, it may be mentioned that from the lateral walls of the zoa'cium issue two flat, sloping calcareous ribs which as a rule meet in a suture distally to the zoa-cial operculum (PI. 1, fig. 5 a, 5 b, 5 c, dw.).
The very earliest trace of an ooecium to be seen in Flustra seciirifrons from the surface of the colony, is a slightly inclined curved line, which at a distance from the operculum nearly equal to its height unites the two lateral borders of the zocecium and rises from the attachment of the distal wall to the inner sur- face of the frontal wall of the zoa'cium. PI. XIX, fig. 8 b shows a longitudinal section through an early stage of an oa-cium, which is a little older than thai just mentioned and shows a distal wall, Ibe basal portion of which is horizontal, while the rest rises distally forming an angular arch and joins the frontal wall, which slill forms a straight line at this place. On the other baud, lig. 8 c shows a small indentation proximally to the frontal end of the distal wall, and this indentation increases in length or depth in the following figures 8 d, 8 e and 8 f, the last of which represents a longitudinal section through a completed ooecium. While it is quite easy to understand that Vigelius, who examined longitudinal sections of decalcified colonies, considered the indentation mentioned to have risen by an invagination of the frontal membrane, it is cjuite evident from the longi- tudinal sections (8 b — 8 f) given here that the endoooecium is only formed by a continued growth of the distal wall, which however at the same time undergoes
58
a strong llexioii and alleralion in shape. Thus, wliili' Ihe angle between llie liori- zontal and vertical portions of tlie distal wall in fig. 8 b is right, and in lig. 8 c obtuse, it gradually becomes more and more acute on account oC the endooo'cium bending backw^ards towards the basal wall of the zoa^cium, without doubt be- cause of the counter pressure brought about by the growth-tension. While the portion between the horizontal part ol' the dislal wall and the jjoinl of the indentation has nearly the same length in the examined longitudinal sections, the indentation on the contrary increases in length, and lastly the oa-cial fold grows down over the oa-cial membrane, which not long before occupied most of the frontal wall of the deveio|)ing oojcium. At the same time as the developing orrcium is undergoing these ailerations in shape, the whole zoa'cium increases considerably in size, and the horizontal part of the distal wall in length.
As already mentioned in the above reference to Vi gel ins" investigations, he believes that the ocrcial membrane dissolves later, so that the egg from Ihe zon^^ cium can reach into the oo^cium, but this view clearly proves to be wrong from the fact, that I have found eggs lying in the oa>cia in Fl. secnrilhuis and Fl. memhranacco-tnincnla (PI. I, fig. 2 a), the floor of which is formed by such an ooecial membrane on which the egg rests. The egg must therefore have come into the ooecium from outside through the oax-iai ai)erture, and possibly Ihe altered position of the ou'cial membrane is due to this transference. Fig.s. 8 g— 8 n show a series of developmental stages of the oo'cium mentioned, seen from the surface of the colony. In the earliest of these (8 g) the ascending part of the distal wall has nol yet l)egun lo calcify, and the deej) sinus between the (wo rounded projections comes from the not yet closed uniporous rosette-plate. The other figures show the formation of the owcial bladder, its partial closure and the formation of the two calcareous ribs.
While the rest of the oa'cinm-bearing members of Ihe family have essenlially the same structure of the ocrcia as Fl. securifrons, we find a rather difierent structure in Fl. folincea (PI. I, figs. 8a, 8 b; PI. XXIV, fig. 8), as the oa-cia here have an irregular egg-shape. Whilst, as already mentioned, a pair of cryptoeyst- ribs occur in /•"/. securifrons proximally lo the operculum of the zocecium, in a number of species, e. g. in Fl. ineinbranaceo-trimcata (Pi. I, figs. 2 a, 2 b, PI. XXIV, fig. 6), 7-7. Barleei (PI. I. fig. ;5 a), /•'/. Schonatii (PI. I, fig. 7 c) etc., a more or less developed cryptocyst-belt occurs just dislally to the free edge of the oa^cium, between this and the covering membrane; the originally separated lateral halves of this belt later fuse together. This belt reaches its highest development in /•'/. fliislruides (PI. I, fig. 4a; PI. XXIV, Lig. 7) and it may in lime quite cover the ooecia, which in this species exceptionally project distinctly on the surface
59
of the colony. In some species, Fl. denticiildta (I'l. I, fig. 9 c), Fl. florea and partly in Fl. fliistroides (PI. I, lig. 4 b) tlie oa'cia are situated inside (he avicularia. With exception of the Farcimiiiaria species (PI. I, figs. 10 a — 10 d), in whicli the ocTcium is enclosed in a kenozooecium, tlie ocecia in the other members of the family Farcimimtiiidae seem to have essentially the same structure as in the Fhistridae, but all of them project more or less on the surface of the colony. In the species of the genus Columnaria n. g. (PI. I, figs. 12 a — 12 d; PI. XXIV, fig. 9), a part of the inner (basal) wall of the ocecium is on each side covered by a triangular cryptocyst-plate, which from each of the lateral l)orders of the zoa'cium pushes itself in between the ectoooecium and the endoon^cium and in Nellia simplex var (PI. XXII, fig. 6 a) the frontal wall of the ocrcium is provided with a cryplocystic belt, like that founil in many Flnstridac. I must also refer to this group the ooecia in Micropora Nonnani (PI. Vlll, figs. 3 a, 3 b), Micr. perforata (PI. VIII, fig. 4), liosselia Rosseli, Biujidopsis Peachii, Buy. ciispidata, Menipea cervi- coriiis (PI. II, iig. 4 b), M. Bu.ski (PI. II, fig. 3 c), Urceolipora nana (PI. XV, figs. la — 1 c, PI. XXIV, fig. 11), Cheilopora sincera (PI. XXIV, fig. 4a), Gephyrophora polijmorpha, the oa'cia in the species of the genus Oniichocella (PI. XXII, figs. 3 a — 3 b, PI. XXIV, fig. 10), in all members of the family Sclerodomidae (PI. XIX, figs. 18 a, hS b), as also in numerous members of the family Catenariidae, for in- stance in Hincksiella pnlchella (PI. XII, fig. 9 a), the sj)ecies of the genus Ptero- cella (PI. XII, figs, oa, 6a), most of the Catemiria species, (PI. XIII, figs. 2a, 3a, 3b) etc. In the majority of the mentioned forms the ocecium projects more or less notice- ably on the surface of the respective zocEcium, and it is only in a small number of cases, e. g. in Urceolipora nana and in the mentioned species of the Catenariidae, that it is ([uite hidden within this. While in a number of cases we only have to do with a membranous ectoocecium, as in Micropora perforata, Bnyulopsis Peachi, Cheilopora sincera, etc., the ectoooecium in others is wholly or jiartially calcified, e. g. in the mentioned Calenariidae, in Biiguhpsis cuspidala and Menipea cervi- cornis. Finally, in both cases there may appear between the endoooecium and the eclooa'cium a more or less developed cryptocyst, as in Bay. cnspidata. Menipea cerricornis and Gephyrophora polijmorpha^ . in the last of which the crypto- cyst covers the whole frontal wall of the endoooecium. The cryptocyst in Urceoli- pora nana on the other hand has (juite a dilTerent position, as it here covers the basal wall of the owcium right down to the place where the oa>cium issues from the short horizontal portion of the distal wall.
b) Endozooecial ooecia, which are surrounded by kenozooecia or heterozooecia.
' no, PI. 11, fig. 22.
60
Tlu' eiulood'ciiiiii, as in llu' loii'i^oiiij; i^roup, is I'oniu'd l)y llif dislai wail iii'- tween two chambers lying in llu- same longiliulinal row, bul while the ecto- oa>ciiiin in that groii]) was only represenled by a more or less distinctly limited part of the frontal mcmiirane of the covering zoo'cinm, it is here so lo speaii represented by the whole covering chami)c'r, which is a Ucno/Od'ciuni. W'c find everywhere a common operculum for the kenozorecium and the owcium. Such oa'cia are found in Didymia simplex (PI. IV, fig. 7 d), Eiwratea chelata, likcllarin infnndilnildld (PI. IV, figs. 4 a— 4 d), Menipea crijstallinu (PI. IV, ligs. 1 a, 1 b), Ciiltiilinit piincldld (PI. IX, iig. lib), Cr. dnnnlatd, Cr. (idltijiiv (PI. I\, lig. 12a), Escharella diiiphana (PI. XVII, fig. 1 a), Ksch. abyssicoUi (PL XVII, lig. 2 a), Enriistonielld fordimnicierd (PI. XVIII, figs. 14 a — 14 b), E. hilahidtd, besides in the Farciminarid species (PI. I, figs. 10 a — 10 c), most members of the family Catena- riidae (Pis. XI, XII, XIII, XV), and the members of the family Ilippothoidae (Pi. XXI, figs. 8e, 8 b, 9 a, 9 c).
The fact that the endoooecial ocecia, besides appearing as a rule in certain families, appear sporadically in more or fewer forms in a number of other families would seem to suggest Ihal they rei)resenl an old oau'ial type, which perhaps was at some lime general, but which later has been replaced 1)\' others. It deserves to be mentioned in this connection Ihal they apjjcar together with hyperstomial (xrcia in Cribriliiia punctdtd (1^1. IX).
2) The hyperstomial ooecia (PI. XXIV, figs. 12 — 18). These oa>cia like the endozocecial consist of an endoooecium and an ectoooecium, which join at the free frontal edge of the o<rcium and form together a fold, the oa'cial Ibid: but they are always situated outside the cavity of the zooecium, and the dislai wall does not take part in their formation, even though they most frequently arise from or in the immediate neighbourhood of its fiontal edge. The two layers of the actual oieciuui are formed by the frontal membrane of Ihe distal zoo'cium, hut between these a cryplocyst layer may sometimes appear, and in many cases the hyperstomial on-cia are pro\ided with an oo^cial cover. This type of onH-ium, which aj)pears in the majority of Ihe Cbeilostoiudld, presents numerous modifica- tions, of which we may mention here Ihe mosl important, bul for the rest refer- ence may be made lo the dilTereiil I'amilles.
We may begin with the oo'cia in Scriipocellarta scabra, of which a series of developmental stages have been figured on PI. II, figs, f) a— 5 f, as they appear when the colony is viewed from the surface and after treatnieni with boiling alkali or cold eau de Javelle. At the time when the frontal wall of the distal zooecium is still ciuite membranous, the first trace of the calcium appears as two small dislai rounded calcareous plates, which arise from the frontal edge of
(jl
the (lislnl wall and soon join in a median suture. This small, bilabiate calca- reous plate, which has arisen IVom calcilication of a part of the frontal mem- brane of the zoo'cium, increases gradually in size, grows semicircular, and is finally grown round by a calcareous framework of the same origin. The just mentioned calcareous plate with a longitudinal suture in the centre, which forms a common wall for the zooccium and the ooicium, is the basal wall of the oa'cium, the frontal part of which is formed by the further development of a fold, the ou'cial fold, arising in the circumference of the plate named. The inner layer of this fold (the frontal part of the endoorecium) is a continuation of the plate, while the outer layer (the ectootrcium) is a continuation of the surrounding calcareous framework.
The calcification of the basal wall of the endoooecium takes ])lace in CaUo- poni Ihimcrili (PI. IX, fig. 3 a), C. aiirita (PI. IX, fig. 4 a, PI. XXIV, fig. 16), Teijella unicornis. T. .Srj/j/ifV/e (PI. IX, figs. 6 a— G c) and Crihrilina punctata (PI. IX, figs. 11a — lid) in the .same way as m Scrap, scabva, and the oo'cium in these is at a very early stage represented by two small sejiarated calcareous plates, l)ul the endoofficium in Caberea Ellisi (PI. II, fig. 6 a) and Demlrotwmia Murraijamt (PI. IV, figs. 2 a — 2e) on the other hand calcifies as a continuous plate, and this seems also to be the rule within the division Ascophora.
With exception of the orecia in the family Onchoporidae, in which the endo- oo'cium as well as the ectoocrciuni is membranous, the endoocrcium seems else- where to be calcified, but in forms with a calcified ectoocecium it is very often extremely thin-walled and breakable, and often not easy to discover on dried material. The ectood'cium may sometimes be membranous, sometimes wholly or partly calcified, and in many cases its structure appears to be constant williin the family or genus. We have for instance a calcified ectooci'cium in the families lielcporitlae, Sniitlinidac and Di.scoporidae, in the genus Cellepora, besides in most of the Porella species, l)ut we find a membranous one in the genera Scijizoporelld. Hscharella, E.scliaroide.s and Pelralia. In the species of the genus ('.(diopora (PI. XXIV, lig. H)) a larger or smaller portion of the ectoooecium is membranous, and the rill, which Hincks mentions for a number of the species of this genus, marks just the proximal border for the calcified i)ortion. The eclooo'cium is also in numerous members of the family Scrupocellariidae provided with a larger or smaller uncalcified portion (PI. II, figs. 7 a — 8 a).
We have already mentioned previously, that a more or less develojjed crypto- cy^tic region may appear in the endoorecial od'cia, between the two layers of the Od'cium, and the same may be the case in the hyperstomial ones. Still I have up lo now only found such a cryptocyst in the genus luuballotlivca (PI.
62
XVIII, figs. i:ia, PI. XXIV, iig. 1,'i), besides in all nicinbers of the family Onclio- poridae (Ft. XIII, figs. 6—9, PI. XXIV, iig. 12), and in both cases tlie wliole frontal wall of the oa-ciuni is provided with such a layer, which is placed be- tween the ecto- and endood'ciuni. There is however this dillerence thai while this layer in Emballolhcca ari.ses high up from the cryplocysl of Ihe distal zocrciuui, in the family Onchopoikkw it arises from the distal wall between Ihe two zocL'cia.
We very often in species of the genus just mentioned meet with the very peculiar case, that the ooecium is formed by three to five adjoining zoa'cia and conse(iueiilly consists of the same number of segments meeting in sutures, of which each single one includes a calcified endooa'cial layer, a cryplocyslic layer and a membranous ectoooecial layer.
We have seen that the basal wall of the od'cium in ScrupncelUtrui sc(tbr(i arises by calcification of a part of the original frontal membrane of the zoci-cium, and nearly one half of the hyperstomial ooecia might be in a similar relation to the zooecium, even though the size of this common wall for the zoa-ciuni and ooecium may be very variable in the diderenl forms and sometimes present considerable dificrences in species of the same genus. It seems as a rule to be large in the families Meinbrdiiiporidae, Scnipocelhiriiddc and Petniliidtie, as also in the genera Eschardla, Escluiroiiles, Schizupurella, Ksclidrina and Microporellu, while it is for example very small in Dendroheaiiia Miirraiianu (PI. IV, figs. 2 a — 2 e), Porella compressa and Smitlind trispinosd. In the genus Smiltina especially the relation between the zo(i3cium and the oa^cium seems to be subject to great variations, and while the common wall in some species is large or of fairly con- siderable size, e. g. in S. boreulis, S. Sinilti (PI. XIX, fig. 4 a), S. palmala (PI.
XIX, fig. 5 a), it is as mentioned very small in .S. hispinosu, and may again l)e quite lacking in other species (S. reticuUda, S. Laiisboroui, S. linearis). In Ihe last case these oa-cia, which we may call indej)endeul, consist of Iwo layers in their whole extent, and are formed by the ofrcial fold alone, while this fold in the previously MHiilioned cases arises in Ihe circumference of a semi-circular area, namely, the parlition-wall lielween Ihe zod-cium and the ooecium. Such inde- pendent ocrcia seem to appear as a rule in Ihe families RicelUiriidde. Hcteporiddc, Celleporidae, Mijriozoidde and Discoporidde, and they may also occur in llie genera Smittiiid and Porella (c. g. in P. saccatn); but as already mentioned there is no sharp distinction between independcril and dejiendent ocrcia, because the parlilion-wall may vary considerably in size. While the independent Od'cia in Ihe above-mentioned Smitliiia species allach themselves so closely lo the frontal wall of Ihe distal zodcium, Ihal it is not jxissible to isolate llieni as a whole, the hyperstomial (xecia in the laniily liicelldriidac on the ollu-r hand are freely pro-
63
jectiiig, so that they can very easily be separated and the same is the case with the ooecia in the genus Thalamoporella and in most species of the genus Discopora, although to a less extent. In the family Reteporitlae also the oa^cia seem origi- nally always to be free and able to be isolated, even though they later get tirmly imbedded in the colony by covering layers, and they seem here, as in the family BicelUiriitldc, always to be provided with a narrow, almost stalked basal part, as is also the case with the Od'cia in Porclhi sdccota.
While the frequently mentioned wall between the zooecium and the ou'ciuni in Malacoslegous forms only consists of a gymnocystic layer, it is on the other hand as a rule wholly or partly two-layered in the Ascophore forms which have a cryptocyst, as within the gymnocyst there is a cryptocystic layer, which some- times covers its whole surface, sometimes only a larger or smaller part of it. This difference seems to depend on how far the ocecium appears at an earlier or later stage of development of the zoa'cium. In species of the genera Schizoporella, Escliarina, MicroporelUi, Petralia and Emlxillotlieca, besides in certain species of the genus Sinittina (5. Lansborouii, S. reticiilala and .S. linertris) the ooecia first appear after the frontal wall of the zooecium is comjjletely formed, so that the basal wall of the oa'cium, which arises by calcification of a portion of the frontal membrane, comes in its whole extent to lie up against the cryptocyst of the frontal wall, from which, however, as a rule, it seems fairly easily detachable. In Emballotheca furcala at the place where an otrcium is going to be formed, we find a deepened, semicircular area, surrounded by a low marginal ridge, and a similar deepened area might also be found in species of the genus Petralia (PI. Will, fig. 5 a), as the ooecia here are in their basal half sunk into niche-like recesses.
On the other hand, in the genera Escharella (PI. XVII), Escharoides (PI. XVII), as also in certain species of the genera Porella (e. g. in P. slriima Norman and P. glaciata Waters) and Sinittina (S. Sinitti, S. Iwrealis, S. palmata etc.) the rudi- ment of the oa^cium, as in Scriipocellaria scalna, is seen at a very early stage in the development of the zocecium, and the cryptocyst, which from the beginning only appears outside or in the marginal region of the basal wall of the ooecium, as a rule gradually grows more or less far in over the basal surface, which as a rule however has a larger or smaller triangular, semicircular or semielliptical, proximal area which is not covered by the cryptocyst. In contrast to what lakes place in the genera Schizoporella, Escharina etc. this cryptocystic layer is here firmly fused together with the gymnocyst wall of the oa-cium, and it is in rare cases, as in Escharoides coccinea and E. Jacksoni, provided with wide pore-canals.
While a calcified ectoooeciiim does not seem to increase in thickness, and this is also the case with the endooa'cium when it is covered bv a calcified ectoori'cium,
64
an ciiilooaHMum as a rule seems to increase in tliickness when the eclood-eiuni is membranous, and this seems generally to he (he case with all calcareous walls covered l)y a membrane. This seems to suggest tluit the cells of this meml)rane deposit fresh layers of chalk on the outer side of the older ones. Such calcareous walls have as a rule a more or less rough surface, and rib-like or ramified thickenings also very often appear on them.
The hyperstomial officia are in many cases again covered by one oi- more calcareous layers, which sometimes arise from one or more of the adjoining zooecia alone, sometimes also from the peristome of the zoa'ciuni itself, and we give here as examples a number of species in which the oa'cia have such a cover, for which may be proposed the name »oa'cial cover*, hi the species of the genera Myriozoiim (PI. XXIV, fig. 18) and Haswellia (PI. XVI, lig. 2 a) the oa^cia, which in their whole extent consist of two layers, are placed in niche-like depres- sions on the frontal wall of the distal zod'cium, and when the ocrcium arches forward so as to form its frontal half, this is grown over by a frontal continua- tion of the niche, which quite closes round the oa-cium. As soon as this closing has taken place, the o(X'ciuni can only fii' seen faintly as an imperfectly limited swell- ing, which in the course of time becomes less and less distinct, because the thick cryptocyst forming the frontal wall of the niche increases in thickness under the covering membrane, which is probably continued over the whole inner surface of the niche. Norman' would undoubtedly call these ooecia »cryptic'. A single, undivided o(vcial cover, which arises from tlu' frontal cryptocyst of the distal zoo'cium, is also found in Porelld sirniiui. Porelht (jldcidta, SiniltiiKi Sniilli. Sniil- liiui Irispinosct (PI. XIX, lig. 7 a), Sniillind iinisj)iiii)s<t: in the last two the oo'cial cover leaves a larger or smaller part uncovered, and in none of these species does it attain a thickness similar to thai in the nu'ntioned members of tlu- family Mijriozoiddc. In contrast to the cases cited the od'cial cover in a number of species is formed of 3 — 5 calcareous plates joined by sutures, which sometimes arise merely from the adjoining zocrcia, sometimes also from the peristome. In Siiiilliiid foVutccd (PI. XXI\', lig. o a) a small proximal part of the zoo'cium is uncovered, and the ooecial cover consists of three portions, which meet together in two proxinuil converging sutures. Of these the middle one comes from the distal zoo'cium, and the two others, which come from the two lateral zoo'cia, each have a large, free, triangular projection, placed distally to the ocecium, and covering over a part of the zocjecial aperture. On the oIIut baud, llu' perislonu' in l)isi(>i)ord Sarsi (PI. XXIV, fig. '2 a) and I'orclld cdiujircs.sn lakes pari in the
' SI, p II.-).
65
formation of the ooecial cover nnd in Porella saccata we meet with an ooecial cover with many laj'ers, because thin calcareous plates are constantly growing over the ooecium from the three surrounding zooecia. A similar, many-layered ooecial cover seems also to be the rule in the family Reteporidae.
An oa'cial operculum (PI. XXIV, figs. 6, 7, 9, 10, 13, 14, 16 o.o.) has u|) to now only been found in Bicellaria ciliata, Biigiila Sahatieri^, Callopora (Memhranipora) Fle- ntincii^ and Microporella M(tliisi\ and it consists in these forms only of an cvaginafion from the proximal zoa-ciiim's mem])ranous wall, as a rule distally to its oper- culum. Into this evagination extends a muscle, which is able to withdraw it and thus open the oa'cium, both for the egg to enter the latter and for the larva to escape. The oa'cial operculum seems to he quite lacking in Porella saccata and in the members of the family Reteporidae, and it is very likely to counter- balance this, that the ooecia in this family are furnished with a more or less developed, screen-like continuation, directed inwards, of the rim of the opening. In Tlialamoporella we find a well chitinized ocEcial operculum, which at its proxi- mal part is connected with the zocecial operculum, and which seems to be pro- vided with a muscle on each side (PI. VI, figs. 7 e, 7 o, 7 n, 7 g, 7 h).
3) The peristomial ooecia. These ooecia, which only consist of a single cal- careous layer and have no covering membrane, are formed by the peristome, and may otherwise be very different in shape. In the family Tiihiicellariidae* (PI. XVI, figs. 3 b, 4 a, 4 b, 5 a, 5 b, 5 d) they have the form of an irregularly pear-shaped expansion open at the end, while in the genus Lekytliopora (PI. XVI, figs. 6 a, () b, 7 a) they form a semi-globular expansion on the frontal wall of the long tube-like peristome. I must for the present also refer the helmet-shai)ed or cup-shaped ooecium in the genera Holoporella and Conescliarellinu (PI. XXIII, fig. 8 a) to this type.
4) The endotoichal ooecia. These ooicia which are only found in the genera Celliilaria (PI. VII, figs. 4 a— 4 f, PI. VIII, 1 a— 1 c, 2 a— 2 c) and Membranicellaria (PI. VII, figs. 2 a— 2 c) are cavities in the thick frontal wall of the zoii'cium, and it looks as if they are formed by a gradual resorbtion of the calcareous material of this wall. Thus by grinding longitudinally the older and younger parts of a colony we can find these ooecial cavities in all possible sizes, from quite small ones, situ- ated in the middle of the thick wall, u|) to a size which takes up the largest part of the thickness, and opens outward. According to the investigations ofC^alvet'*
' il, p. 57. ' 9, p. 262. ^ 9, p. 1(19. ^ My (.'Xiiinination <if these o(ecia lias l)eeii made on dried malerial, but Waters lias later lltii given a lull aecount of them, based on fresh spirit material. ' 9. p. 2(14, pi \'l. li-. II
5
66
there is an opening between the zocEcium and the ooeciuni in the separating wail, but I must disjjute its presence, as I liave always by transverse grinding found the separating wall unlirolvcn. Calvet has found an ooecial operculum with two layers, which is opened Ijy a muscular apparatus.
5) The double-valved ooecia (PI. VII, figs. 3 a, 3 h, 3 i, 3 j, 3 k, 3 I) which have hitherto only been found in Aliisidiiim ixtrasiticnin, consist of two double layered, arched valves, the edges of which meet together and with the zooL-ciuni bearing them form a bean-shaped body. They rise from zott'cia, Ibe oral surfaces (PI. VII, 3 c) of which form nearly a right angle with the longitudinal axis of the zoircium, and the two valves arise in the lateral borilers of the said surface on each side of the zooccial aperture, which leads directly into the bottom of the ooecium. As each of the two hollow valves has an inner connection with the zocecium through a pore-chamber, we must regard them as two kenozooecia (see under Ahisidiuiu pardsiticiiiu).
()) The acanthostegous ooecia. We indicate by this name the cavities found in the two Elvctia species, E. zostericohi (PI. IX, fig. 2 b) and E. (Hctenvcium) amplectens (PI. IX, figs. 1 a, 1 c), which externally are limited by two lows of hollow spines meeting together in the middle line of the frontal surface. The od'cial cavity in E. zostericola is bounded internally by tlie frontal membrane of the zou'cium, and externally by the mentioned spines, and according to Ostrou- moff this cavity contains developing larvae. While the zooecial operculum in the species mentioned is placed at the distal end of the ooecium-bearing zoa^cium, in the corresponding zoacia of E. amplectens it is situated proximally to the area formed by spines, and as this species has only been examined in dried condition, nothing is known as to how far the ocBcial cavity also here is bounded in tlie same way as in E. zostericola.
Before leaving this subject, we may briefly touch upon the question of the egg's transference into the oircium. The older view that the egg is carried from the zoa-cium (or gonozo(i'cium) into the oaxium througli an inner connection seems according to Jullien's investigations to hold good for Hippolhoa hijalina, in which sj)ecies the gonozooecium and the orecium form a common cavity, closed by a common operculum. According to Jul lien- the zoa>cium has no polypide but contains an ovary, and he supposes that the tentacular sheath is of service to the egg by carrying it over into the ocpcium. A similar direct trans- ference probably occurs also in all the cases where endoocecial ooecia are present with an operculum in common with the zoa-cium (llippotlioidac, ('.iilrniiriulnc. etc.).
' 90, p. 19. '' 4,5. p. 31.
67
On the other hami, we have noticed that the endozooeclal ooecia in Fliistra are quite separated from the cavity of the zocx^ciuni by the ooecial membrane, and a transference of the egg from the zoa'cium into the ooecium can therefore only take place by tiie egg iirst leaving the zoa'cium through its aperture and after- wards entering the oa-cium on the withdrawal of the operculum of the latter. As we have nowhere been able, except in the above-mentioned case, to find an inner connection between the zoo^cinm and the ooecium, we cannot doui)t but that the egg elsewhere always leaves the zooecium through its aperture. This is undoubtedly most evident in the pcristomial and the doul)le-valved oa'cia, be- cause the zod'cial aperture leads directly into them, and the same is the case with the ooecia in Tbalamoporellii; but neither can we in any other /^n/ozoo find in the relation between the zooecium and the ooecium any difficulty for such a transference. Without entering in particulars I shall here only state that in all the species with ottcia, examined by me, the position of the ooecium in relation to the zoo-cial aperture is a such that when the operculum opens to a certain extent the egg will have no difficulty in reaching into the od'ciuni, whetber the transference be etTected by aid of tbe tentacular sheath or by an independent movement of the egg. Especially in tbe Ascophora this passage seems to be secured in the best possible way as in most members of this division the zoa>cial oper- culum in a certain position closes a space which can be looked upon as a common vestibulum for the zooecium and the ooecium, and a completely covered passage is thus formed between them. Least safe the passage seems to be in the family Reteporidae and the genus Exochelht as there is a rather long way be- tween the zooecial aperture, and the oa-cium and the zorecial operculum cannot close the space between the zooecium and the owcium.
The systematic characters in the Cheilostomatous Bryozoa.
While we sometimes find in the literature, as in Hi neks. Waters, JuUien and other writers, views concerning the larger or smaller value of different syste- matic characters, the systematic importance of a single character being some- times dealt with, sometimes the relative importance of several characters, yet any connected or more complete review is lacking of those characters, which in the present state of our knowledge might be used for systematic purposes, as also a valuation of their relative importance based upon a sufficient number of examples for it is only in this way, that tbe reader becomes able to judge in the matter. We shall endeavour here to give such a review and we shall first distinguish between two dilVerent categories of characters, namely the »colonial» and the »zooe- cials meaning i)y tbe first those which can be referred to colonial forms and the
5*
68
colony's composition of one or more difTerent, individual forms, while the last are those which are found in the structure of liie single zoo'cia.
Colonial form and mode of growth. Throughout the organic world wherever single individuals are uniteil into colonies or in florescences we lind a repetition of the same colonial forms oi' forms of growth. The colonies may he incrusling or free foliaceous or branched in various ways, the single indi\i(hials arranged in one layer or two, in one, two or more rows etc., and this harmony in Ilie outer arrangement may often produce a surprising likeness between animal forms very different in slructure, occasionally even between certain animal and plant forms. It is therefore easy to understand that the lirsl investigators of the numer- ous aggregate animals of the sea, the single individuals of which only reveal their peculiarities on very close examination, have tried to arrange this varie- gated multitude after likeness in the colonial form. We may for example refer to Ellis' celebrated work on the Corallines', under which common name be not only classes hyilroid polyps, Bvijozoa and corals, but also certain calcareous algae. By and by as knowledge of the single individuals of the colonies advanced, the systematic importance of the colonial form becomes more and more limited, as it is gradually used for less and less extensive systemalic units, and in the pre- sent day /Jryoroa system, which is founded on Smitt's and Hincks' well-known works, it occupies a very subordinate position. As there is nevertheless too much importance still attached to the colonial form as systematic character, not only within the Bryozoa, but also within other aggregate animals, for instance the hydroid polyps, I do not think it unnecessary to discuss this question here, and I may first quote some observations concerning this made by Hincks-. After having spoken about the slight hel|), which the j)olypide, and the avicularia give us in systematic regards, he says: »There remain the characters of the cell itself and the habit of growth. It can hardly be deemed doubtful which of Ihem should have the |)recedence in a natural system; we may go very much furlhei-, indeed, and say llial in such a system the latter must hold a very secondary and subordinate place. The essential structure of the cell, as one of the primary zoa'cial forms, must certainly be accounted the most imj)ortant point, holh in it- self and as a clue to relationship. The mere habit is, so to speak, a suj)erinduced condition, which may be difTerent in the most nearly related and similar in the most divergent forms; and groups based on it, instead of fitting in with natural affinities, are found to traverse them at all points*. A little further on' he also slates: »In the Escharine group it seems to me that the families and genera
r.' ' •>•>. Introtiiiclioii. p CXXVIII, ' p CXXX.
69
should l)e based almost wholly on the zoa'cial characler; but I am certainly not prepared to hold that other structural elements should never be taken into ac- count. The Flastridae, which seem to constitute a most natural grouj), have a true Membraniporidan cell, and hold their separate place by virtue of their corneous and foliaceous zoaria<'. As a consequence of the weight the writer attaches to the colonial form in the family Flastridae, he refers an incrusting species Fliistra (Memhranipora) /liistroides Hincks, which in its essential characters is a Fliistra, to Meinbivtnipora at the same time that he indicates in its specific name its likeness or relationship to other Fliislra species. Gemelhiria is also a genus, which in Hincks is based essentially on the colonial form.
A. M. Norman' takes up a somewhat similar standpoint to that of Hincks, which he expresses as follows: »It has been argued by recent writeis that the form which a colony of a polyzoon belonging to the Cheilostomala assumes is of no moment in generic character. Electro piloxn lends strong support to this view. Yet it is a view nevertheless in which I am not prepared in all cases to acquiesce. The zon?cial characters are unquestionably all important, hut no lasting classification can be based on any part of the zooecium, whether it be the mouth- o])ening, wall, rosette-plates or anything else. Why also in all instances is the ultimate growth and form of the zoarium to be excluded from generic character among certain families of the Cheilostomatu, and at the same time to be recogni- zed among the Cyclostomata and Ctenostomata, and even other groups of the Cheilostomatd'! This is surely scarcely consistent. In some instances, as for example in Electra pilosa, the form of the colony is of no generic and specific value, but in other cases it may be and, I believe, is«. To judge from this statement this writer seems more inclined than Hincks to use the colonial form as a .syste- matic character, and this appears also in his last paper' on the Brijozoct, since he here maintains the old Fliistra genus Cnrhasea rejected by Hincks, which is only based on the fact that the colony has a single layer. There is of course no doubt, that any character constantly appearing in a systematic division must be regarded as being of systematic value, and the same must also be the case with the colonial form. Wherever therefore this appears constantly within a genus or family it ought to be emphasized in the diagnosis. But the proof that the respective genus or family is a natural one is only given when evidence has been obtained of sufficiently great agreement between the single species in regard to the structure of the colonial individuals, since for instance the same form of colony may appear in the Brijozoa not only within the three natural main divi-
82, p. 122. ' 8,'!, p. 581.
70
sions: Clieilostoimitd, Ciicldstoinald and (Itenoslomatd, ))iil in the first division also within a scries of widely dilTerent families and genera. Thus the nel-like connec- tion of the hranches of the colony, so common in the family Retci)t>ri(l(ie, we also find in several Ciiclosloinata {ReiicuUimni, livlicrisina, Retihornerd), in several species of the family AdeonUUie (e. g. in Ailcona (irisca, A. dppemliculitld, A.WUsnni), in the species of Ri'lijhixlra as also m Mciiihrdniixira sigilldtd^ i\nd Pelrdlia iiiidata. A colony consisting of cylindrical, or })olygonal internodes generally connected by flexible chitinous bells is found in such widely difTerent forms as most spe- cies of the genus Celhildrid, species of the genus Tnhiuelldrid, the species of the genera Fdrciniiiiaria and Nellia, Microporiiia borcdlis, Schizuporella ininiersd and species of the Ctenoslome genus Fliistrella (Fl. dichotoma and Fl. Binder!). We have here only mentioned some of the most peculiar forms of colony; for of the more common, e. g. free colonies with Ihxt branches, we might cite numerous examples. This colonial form is the most prominent in the families Fliislri<lae and Bicellariidde, and the particular stress which has been laid on the colonial form, as far as the first family is concerned, has, as we shall see later, resulted in several members of the family Bicellariidde being described under the name of Flustra. Just as the same form of colony may on the one hand appear within widely different families and genera, it is on the other hand not always constant even within the species, and numerous sj)ecies can appear in two or three difTe- rent forms of growth. The colonial form can therefore not at all he used as a specific character with certainty. One of the species which otTers the most striking example of variation in regard to form of growth is Electra jiilo.sd. While this sjiecies is at our coasts only known in an incrusting state, Norman has found it in the Throndhjcm Fjord growing in free colonies of very difTerent shape, sometimes with tiie zooecia in one row, sometimes in two, sometimes with F/iis/ra-like or (^elliilarid-Vike branches, and this author gives altogether 10 diffe- rent forms of growth for this species. Tiie following may be mentioned as ex- amples of species, which appear not only incrusting, but also in free, foliaceous, one- or two-layered colonies: Membranipora arcticd, ThaUimoporeUa Rozieri. Th. liotichd, SteijctnofMrella Biiski, St. mafinilahris, St. tnincala. Leprdlid- I'dlldsiana, Smittiiid folidceu, C.heilopura sinceru, Discupora pavonellu, Disc, scdbrd, Disc, plicata, Escharella lubiatu. Disc. Sarsii, /i.sc/i. rosacea, Porella struma, Porella compressa, Porelld Skcnei, Smiltiiia Irisfiino.sd, Sin. Ldnsborovi. The question, how far it would be correct in any case to limit a species, genus or family from one or .several others only on the basis of difference in the colonial form, must therefore be
' io:i. p. s.
71
answered absolutely i" Hie negative, as agreement in regard lo the I'orm of colony, according lo the data given above does not give anj' guarantee for real rela- tionship.
When Norman points out the inconsistency of rejecting the form of colony as a systematie character in the Cheilnstomata though it is used in the Cijclo- stomata and CJenostonuthi, we must remark that as the zooecia within the division of the Cyclosloiudld have nearly the same structure, it has been necessary to choose the characters from the way in which these zorecia are arranged. I do not doubt however that the classification of the Cijclostoinata also requires reform. I shall not in this work enter further into this question however, but only men- tion as an example that a new species from tlie Danish cretaceous formation Diastopora carinata, may appear both as round discs and as free cylindrical stems, which sometimes have a wide inner cavitj', sometimes an axial canal, fine as hair. This species may thus be referred both to Diastopora and to Canaria. An- otiier species, Diastopora conij)ressa, occurs both as unilamellate and as bilamel- lata expansions, and would consequently be referred to Diastopora as well as to Mesenteripora, the latter of which genera Pergens even refers to another family. On the whole, the classification seems to me more natural within the Cteiwsto- ludta. For the rest, in dealing with the classification it is impossible to be consi- stent in the sense that we must everywhere attach the same value to the same structural feature. It proves on the contrary that the same structural feature in difTerent systematic divisions can have a very difTerenl systematic importance, so that characters which are constant in one genus or family in other corre- sponding divisions are not always constant even within the species.
The occurrence of one or several forms of individuals in the colony.
The fact, that a colony can contain one or more forms of individuals, which are absent in another, does not exclude the possibility, that the two colonies can belong to the same genus, or even to the same species. Considering first of all the hetcrozocEcia, their occurrence in manj' cases is, as known, very inconstant within the family, genus or species, because they can be absent in more or fewer genera within the family, and in more or fewer species within the genus. Even within the species their appearance is often inconstant, and we may cite the following species as examples, in which they can sometimes be absent, some- times present: Schizoporella unicornis, Sch. sangvinea, Escharina s(/)i/)/e.r, E. Alderi, ^Lepralia'^ Pallasiana, L. pertusa, L. edax and Discopora verrucosa. We can there- fore not base a genus, nor even a species on the presence or absence alone of heterozocecia. On the other hand, there is a whole series of families and genera.
72
in which the helerozooecia are either constantly occturing or always absent anil in that case their appearance or absence will help to characterize the repective families or genera. For instance the absence of avicularia is to such a degree bound up with the notion Electra, that the discovery of an avicuhiria-bearing /i/ec/ra species would rightly be looked upon as very remarkable. We may mention the Adeonidae, Catenariidae, Celleporidae, Holoporellidite and Tbalamoporellidac as ex- amples of families with constantly occurring avicularia, while these are absent in the Aeleidae and Steyanoj)(>rellid(ie. They appear for instance constantly in the genera Callopord and Exuchella, while they are absent in the genera Membrani- poru (s. str.) and Electra.
The oci'cia present a similar inconstancy in their occurrence to the hetero- zoo'cia, as they are (juite absent in a number of families (e. g. Adeonidae. Slegano- porellidae and Aeteidcie), genera (e. g. He<ini(t, Meiubraitiporu (s. st.) Cupid<tri(i and Lunularid) and species, and in many sjiecies they ap])ear very inconstantly and by no means in all the colonies. For instance, in Discopora uerrucosa we only find ocecia in the colonics from deeper water, never in coastal forms. There- fore a genus or species cannot be based only on the ditlerence, that they have or are without ooccia, whereas a constant occurrence of these formations can be used as an auxiliary character. What has been said about the systematic value of the fact, that heterozocecia or ooecia occur in a species, genus or family, does not exclude the different structure of the heterozocecia and the otecia from having a great systematic importance and we shall discuss this matter further in the following sections.
With regard to the kenozooecia, their systematic impDrtance is very diverse, and the small triangular spaces for instance, which appear between the zou'cia in different forms, are not always constant in the species. This applies for ex- ample to Membranipora Lacroixi. That the so-called radical fibres, which serve to fasten freely growing colonies of less solid materials, only have a very slight system- atic importance, is evident, partly from Ihe fact that they are found in so many families (c. g. Flustridae, Bicellariidae, Cellidariidae, Scrnpocellariidde, Cotenariidae etc.), partly because their occurrence is dependent on the free condition of the colony, which has no systematic importance. We may give here a few examples to show that the radical fibres can be present or absent in forms of growth of the same species as well as within closely related species. Such radical fibres can for example be found in Stej/anoporella neozekinica, which occurs in pillar- shaped trunks, while they are absent in an incrusting form, which Harmer considers as a variety, var. magnified, of the same species. A similar relation is found between the freely growing species: Microporella fldbellaris and Mic. margi-
73
iiula and llie iiicrusting Micr. cilidtct us well as between a (Veely growing, richly branched Japanese Micropnrella wliich is closely related to M. Mdlusi, and the last-mentioned, as a rule incrusting species. Genera based on the presence of radical fibres (e. g. Craspedozoiiin, Fliislrainorplui) will for these reasons be just as artificial as genera based on the lorni of the colony, but this does not ex- clude that differences in the appearance of the radical fibres may sometimes be of use as auxiliary characters, e. g. in some genera of the family Bicellariidae. A much greater systematic importance must be given to the flat kenozooecia, which in all freely growing Releporidac not only form the incrusting part of the colony but also a covering of its basal (as a rule the outer) suiface. Although on account of their position they can only occur in freely growing species, they are namely characteristic for the family Heteporidae, and are found in all members of this family, occurring as free colonies. A still greater systematic importance is held by the lateral chambers, so characteristic of the family Catenariidae, which may appear in each zooecium up to four in number on each side, and which besides the imj)ortance they have for the distinction of the family also in many cases offer good generic and specific characters.
The Heterozooecia, as is known, may sometimes occur independent or vicarious, taking the place of a zocrcium in the colony, sometimes dependent and situated on the zoa'cia, and in the last case they may in one way be regarded as organs belonging to these. The vibracles, which appear on the basal wall in Caberea and other genera of the family ScnipoceUariidne, occupy a peculiar intermediate posi- tion between the independent and dependent heterozooecia ; for while in other cases the latter are always connected with the zocecia by a common wall, these vibracles have an independent basal wall, and can therefore be separated from the zocecia. The ditTerence between independent and dependent heterozoa^cia is of systematic interest, in that certain systematic divisions (families and genera) only have independent heterozoa'cia, others only dependent, while again others present both kinds, not seldom in such a way that they occur together. The independent Iieterozoojcia have their main extension in the division Amiska, where thev' appear unmixed in the families: Flustridae, Cellidariidae and Tlmlamo- porellidtw, l)esides in the genera Ouijchocella, Scleuaria, Cjipiddrin and Liuuildria: The majority of the Membraniporinn and (jibrilinci forms may have dependent heterozocEcia, though independent ones do appear in not a small number of species, e. g. in Membraniporinn crassimarijinattt, M. cnrniyera, M. pijruhi, M. plana, M. velaUt and in Figulinu (igidaris. While all the other species of the genus Callopora have dependent heterozooecia, we find at the same time independent in C. craticula. Independent heterozooecia seem to occur in all members of the
74
laiiiily Adeoniildf williiii llic division Ascoiiliora, l)iil ns a rule together with de- pendent ones. Othei'wise they :ij)pear very seldom in this division, and are for instance found in Schizoporclld sixukjUcs. Arlhicjioiud C.ecili, var., Schizothecci fissn and Chorizoponi BrniKju uiiii.
The most important dilTerenee in slrueture, whieh the heterozotreia present in systematic regard is the presence or absence of a calcareous transverse bar between the o|)ercular and the subopercular area. It is namely, except in a lew cases, absent in the division Aiuiska, and, except in the family Adeonidac and LeieHchura crnslacea, it is found everywhere in the division Ascophoni. The ab- sence of such a transvei'se bar in '■Lepr(ili<i« Poissoni and in Doriiporclhi sjHilhiili- fcra makes it j)robal)]e that these forms belong to the division Anaska. On the contrary the difference between the avicularium and the vibracnium, has gener- ally taken no real systematic importance, and the same heterozott'ciuni may appear in the same genus, even occasionally in the same species, sometimes as an avicularium, sometimes as a \ibraculum. This is the case e. g. in Microporella ciliata, and the genus Microporella as well as the genus Escluirina may serve as examj)les of such a variable develo|)ment of the two heterozoa>cial forms. While the hcterozod'cia within the division Ascophora, where Ihej' are mostly developed as avicularia, only very seldom show so great a modification in their structure that it can be used by the separation of families and genera, there is a much larger diversity in the structure of the heterozorecia in the division Anaskti, and most of the heterozooecia, which by their {)eculiarities help to characterize the families and genera, are vibracles. While the peculiar, freely moveable, bird- headed avicularia are characteristic of the family IVuellnriidac, we lind more or less peculiar vibracle forms in the genera Caberca, Scrupocellaria, Oiujclwcella, Selei}(iri<t, Cupularut and Liuiul(iri<i. The avicularia in the family Aileanidae have a great systematic interest, as they not only differ from the avicularia in all other Ascoj)lior(t by lacking the above-mentioned transverse bar, but they also show a constant character in the avicularia mandible, which is provided wilh a muscular process on each side at the proximal part. The occlusor muscles may also present differences, as they are as a rule double, more seldom single, and this is just the case in the Adeonidae.
The ooecia, as we have already noticed, appear in a series of widely different types, of which again a single one (the hyperstomial) shows fairly considerable modifications. Although their systematic imj)ortancc is rather diminished by their inconstant apj)earance I must yet look upon them as some of the most im{)orlant formations in systematic regard, and there is no doid)t that they are far more im-
75
porliuil than the helerozoa'cia. While these very seldom present family or generic c-haraclers and it is for instance unusual to meet such peculiar, or in their character so constant, avicularia as those we find in the families Bicellariidae and Adeonidae, the oa'cia in most families and in a number of genera present systematic characters of greater or less importance. We might here recall the oci'cial structure in the families Fliislridae, Farciminariidae, Bicellariidae, Cellnla- riidae, Thidamopovellidae, Catenariidae, Hippothoidae, TubiicelUiriidae, Onchoporellidae, Alysidiidae, etc. The most widely distributed oa'cial type is the hyperstomial, which again may present a series of different modifications. While thus the od'cia in the Bicellariidae and Releporidae are free, they are as a rule connected with the zofccium in the larger part of their basal wall. Other dilTerences are; that the ectoooecium may be membranous or calcareous, and that the calcareous surface of the occcium may be entire or provided with pores, though the last- mentioned characters are not of the same use everywhere and present many exceptions. While the ectooa-cium in the genus Scrupocelhiria may sometimes be entire and sometimes with pores, it is generally provided with pores in the genera CeUepora, Discopora, Hippothoa and Siuittina, and only a very few species are exceptions from this rule. In the large family Releporidae the ooecia are either entire or provided with a linear or three-foliate Fissure, and only one single species is further provided with a few scattered pores.
Anatomical characters. These are the characters derived from the organs included in the zocecium, consequently from the polypide, the muscles, the compensation-sac, etc. The structure of the polypide has up to the present hardly been subject to any comparative study in the Cheilostonutta, and it seems reaso- nable to suppose that .such an investigation of this division, just as in the Cleiw- stoinala, might show differences which would be of importance as distinguishing characters. Thus certain Ctenostome genera (Botverbankia, Vesicularia, Ainatliia), as we know, are remarkable in that they possess a gizzard while the lophophore in Flnslrella in contrast to the condition in Alciionidium, is furnished with a ciliated longitudinal furrow and two vibratory threads. That there are also differences in the structure of the alimentary canal in the Cheiloslomata appears from Busk's observation, that the coecum is absent in Urceolipora nana and Carbasea Moseleiji, the last species of which no doubt also belongs to the family Onchoporidae, in the other members of which we should therefore find possibly the same characters. The parietal muscles in the Clieilostomata may, as is known, appear in difTerent ways. Whilst in the Malacnstega they are attached at one end to the calcareous lateral walls, and at the other to the membranous frontal wall, in the Ascophora
Aei///i/5eA/, (2, Pi. R.
"N
-^^t* i*i»^<>u.«'
L-'^UAliW
1(
!
74
family Adeonlddc wilhin llu" division .\scoj)hi>r(t. hul as a riili' logelher witii de- pendent ones. Otherwise they appear very seldom in Ihis division, and are for instance fonnd in Scluzoporclhi spoiniiles. Arthrnpomd Cccili, var., Schizolhecd fissa and Cliorizopora Bronifuiarli.
The most important difference in strnctnre, which the heterozoopcia present in systematic regard is Ihe ])resencc or ahsence of a calcareous transverse bar between the opercular and the subopercular area. It is namely, except in a few cases, absent in the division Aiuiska, and, excej)! in the family Adeonidoe and Leieschara Crustacea, it is found everywhere in the division Ascophora. The ab- sence of such a transverse bar in 'Lcpr(dia« Poissoni and in DonjjiorcUa spalhali- fera makes it probable that these forms belong to the division Anaska. On the contrary the ditference between the avicularium and the vibraculum, has gener- ally taken no real sjstematic importance, and the same heterozon^cium may appear in the same genus, even occasionally in the same species, sometimes as an avicularium, sometimes as a vibraculum. This is the case e. g. in Microporella ciliata, and the genus Microporella as well as the genus Escharina may serve as examples of such a variable development of the two heterozocccial forms. While the heterozooecia within the division Ascophora, where they are mostly developed as avicularia, only very seldom show so great a luodification in their structure that it can be used by the separation of families and genera, there is a much larger diversity in the structure of the heterozotccia in the division Anaska, and most of the heterozocrcia, which by their peculiarities help to characterize the families and genera, are vibracles. While the peculiar, freely moveable, bird- headed avicularia are characteristic of the family liicellariidae, we find more or less peculiar vibrade forms in the genera Caherea, ScrupocelUtria. Oitijchocella, Selenaria, Ciipniaria and Liinularui. The avicularia in the family Adconidae have a great systematic interest, as they not only dilTer from the avicularia in all other Ascophora by lacking the above-mentioned transverse bar, but Ihey also show a constant character in the avicularia mandible, which is inovided with a muscular process on each side at the proximal part. The occlusor muscles may also present dilferences, as they are as a rule double, more seldom single, and this is just the case in the Adeonidoe.
The ooecia, as we have already noticed, appear in a series of widely diPTerent tvpes, of which again a single one (the hyperstomial) shows fairly considerable modifications. Although their systematic importance is rather diminished by their inconstant appearance I must yet look ui)on them as some of the most important formations in systematic regard, and there is no doubt Ihal they are far more im-
Ifr %
I f« H
75
porlant than the helerozoa'cia. While these very seldom present family or generic characters and it is for instance unusual to meet such peculiar, or in their character so constant, avicularia as those we find in the families liicellariidue and Adeonidae, the oa>cia in most families and in a number of genera present systematic characters of greater or less importance. We might here recall the oa>cial structure in the families Fliistridae, Farciminariidae, Bicellariidae, Cellidd- riidae. Thidamoporellidae, Catenariidae, Hippothoidae, Tubucellariidae, OnchoporeliuUie, Alysidiichte. etc. The most widely distributed oojcial type is the hyperstomial, which again may present a series of different modifications. While thus the ooecia in the Bicellariidae and Reteporidae are free, they are as a rule connected with the zooecium in the larger part of their basal wall. Other dilTerences are; that the ectoooecium may be membranous or calcareous, and that the calcareous surface of the ocecium may be entire or provided with pores, though the last- mentioned characters are not of the same use everywhere and present many excejitions. While tiae ectootrcium in the genus Scrupocellaria may sometimes be entire and sometimes with pores, it is generally provided with pores in the genera Cellepnra, Discopora, Hippolhoa and Siniitina, and only a very few species are exceptions from this rule. In the large familj' Ueieporidae the oo'cia are either entire or provided with a linear or three-foliate fissure, and only one single species is further provided with a few scattered pores.
Anatomical characters. These are the characters derived from the organs included in the zoa'cium, consequently from the polypide, the muscles, the compensation-sac, etc. The structure of the polypide has uj) to the present hardly been subject to any comparative study in the Cheilostomata, and it seems reaso- nable to suppose that such an investigation of this division, just as in the Cleno- stonutla, might show differences which would be of importance as distinguishing characters. Thus certain (>tenostome genera {Bowerbankia, Vesicularia, Ainathia), as we know, are remarkable in that they possess a gizzard while the lophophore in Flnstrella in contrast to the condition in Alcijonidium, is furnished with a ciliated longitudinal furrow and two vibratory threads. That there are also differences in the structure of the alimentary canal in the Cheilostomata appears from Busk's observation, that the ca'cum is absent in i'rceolipora nana and Carhasea Moscleyi, the last species of which no doubt also belongs to the family Onchoporidae, in the other members of which we should therefore find possibly the same characters. The parietal muscles in the Cheilostomata may, as is known, appear in dill'erent ways. Whilst in the Malacostega they are attached at one end to the calcareous lateral walls, and at the other to the membranous frontal wall, in the Ascophora
r
I I I
f 1 '
76
tliev are allached lo Ihe conipe'n.salioii-.sac, which has arisen either as an in- vagination or as an oulpusliing from thai cover. In SteyannporclUt, ThdUtmoporelUi and Micropnrti iincifera they are represented by a single iiundie on eadi side reaching to the covering membrane through the two openings (»opesiulae« Jull.) in the cryptocyst, which appear in tlie forms mentioned, and still more remark- able is their appearance in Microporiiui horcdlis, as they here unite the crypto- cyst with its covering membrane but are otherwise, as in Malacoste(j(i, placed in two longitudinal rows. Waters' has pointed out another structure which on closer investigation might prove a tlistinguishing character, namely the »suboral glands*, which are placed on each side proximally to the operculum. They seem to appear in most Ascopbnra, although according to Waters they may be absent in some few sj)ecies, as in Cheiloponi sinceni and SiuiUiiid paliuatd, whilst up to the present they have not been found within the Anaska. While all the organs mentioned only presumably present distinguishing characters, the compensation- sac on the other liand is an organ of very great systematic importance, as it is the means of separating the Cheilnsloiiuihi into two main divisions: Ascophora and Anaska. Against the common rule, it opens in a number of genera (Micro- poreUd, Iiwersiiila, Haplapoiud, Adeniui, Adeonellnpsis, Cdlwellid, Onchoponi, Oiuho- porelld, Tuhiicelldria) not immediately ])r()ximally to the operculum, hut through a median pore (the Ascopore) further back, and a number of these forms (the species of Haplopoma, Adeona and Adeoncllopsis) have been wrongly referred to Micro[)()reII)i.
Calcification. Though the ditference in firmness or density of the calcareous skeleton can not be expressed cjuite exactly except by the aid of chemical ana- lysis, it is in many cases already so distinct from a general zoological examina- tion, that it must be regarded as a good auxiliary character in the distinction of a number of families. We find the weakest calcification in the families liircl- Iciriidiic and Fliistriiilde in which the frontal wall is wholly or mostly uncalciticd, but on the other hand in the family Onchoporidae, the members of which have a completely calcified frontal wall, the calcification is not mucli more solid than in the BiceUarildde. The families Adeonidde and Miiriozoidde are diaracterized bv very thick-walled zooecia, while the very firmest and hardest calcareous substance is undoubtedly to be found in the lieteporidae and Sclerodomidae. The dilference in regard to the firmness of the calcareous skeleton seems to be very slight within all natural families and must therefore be regarded as a good expression
' 108/ 1
77
for the lelationship. On the other hand, the mode of calcification seems to have only a slight systematic importance, hecause it often varies, not only within the genus Init also within the species (see pai;. fj).
The frontal wall. As we have already fully discussed the ditTerences, which occur ill llu' slrucliire of the fronlal wall under the morphology of the zoa-cium, we may content ourselves hei'c with a brief reference to this (piestion. While Jul lien and later Canu attach such a great systematic importance to the crypto- cyst, that they on the basis of it divide the Cheilostomata into two main divi- sions: Diplodenudta and Monothtnuthi, we can only from the investigations we have made on its extension in the difi'erent families (see pag. 13 — 16) regard it as an auxiliary character. It is for the present not easy to judge to what extent it can be used as such, since in many cases it is difficult to decide, whether dried or even spirit Bnjozini have a cryptocyst or not. We may for instance mention, that out of the whole material, which the zoological Museum of Copen- hagen jiossesses of Esclutroides coccinca, only a very few colonies of the genus show a distinct covering membrane. \\'hile the frontal wall in some forms, e. g. in the species of the genus Electra, the members of the families Hippolhoidae and Catenariidae is only formed of a gymnocyst, and in others e. g. the Onijcho- cella species only of a cryptocyst, both modes of calcification are represented on this wall in most of the Cheilostomata. The cryptocyst shows a veiy remarkable condition in Steganoporetla and Thalamoporella, as it descends more or less deeply into the zofficium through two (more seldom one single) openings proximally to the aperture and may even reach the opposite wall. Still more peculiar is the condition it shows in the genera Cellularia and Membranicellaria, because the surface of the colony is divided by a network of ridges into a number of areas, which do not correspond at all with the real zott'cia. We have also seen that the calcification of the frontal wall may take place to a very varying extent, so that we can find all possible transitions between a cpute uncalcified and a (|uite calcified fronlal wall, and the characters derived from the dillerent extension of the calcification are therefore more or less relative.
The pores. I have already called attention to the fact, that a number of the so-called pores seem to have a similar structure to that of the rosette-plates; but as time and material have not allowed me to carry through such an examina- tion everywhere, I shall here under the name of pores include all [)ore-like foruialions, which in contrast to the rosette-plates are situated on free surfaces. The pores are certainly amongst the formations, which have the least systematic importance, because in most families and genera where they ajjpear, they are
78
subject to gient variation in occurrence. This does not exclude the possibility however that in a number of cases they may be good auxiliary characters. As a rule the pores are absent in the division Maktcoslega. where they no doubt are replaced by the membranous frontal area. In most species of the genus Electra however, we find pore-like spots which in reality are only thin places in the gymnocysl. On the other hand, we find pores in most other CheUosloinnla, but they are constantly absent in the zotrcia of the genera Cellulariu, Hippothoa, Chorizo- pora and Eiithyroicles. They appear generally only on the frontal wall, and on the basal wall only in the families Eiithi]ridae and Petraliidae, the latter family of which mainly embraces free forms with one layer, and the basal wall is very often furnished with one or a few pore-chambers, more rarely with scattered pores. The pores on the frontal wall may appear as marginal pores, or as scattered; but this separation is not always sharp, because the marginal pores may appear in several rows, and thus gradually extend over a larger or smaller part of the surface, and cpiite apart from this transitional state the ])ores in several species may appear sometimes as marginal sometimes as scattered pores. Tliis is for in- stance the case in Porella concinnu, Escharina Hijudmanm and Haplopoma impressa. We may cite the Steganoporellidae, Thalamoporellidae, Petraliidae, Hippnpodin'uUte and Microporelld as examples of families and genera in which scattered pores appear constantly, while the pores are more variable in their occurrence within the genera Escharello, Escharoides and Smitlina, as well as in the family Adeoni- dae. In the families Reteporidae, Celleporidae and HoloporeUidae we find as a rule a verj' small number of pores, which are mostly situated on the marginal por- tion of the zooecium, and in the family Onchoporidae we have external rosette- plates appearing in small number in the distal half of the zoo'cium.
The spines in regard to their systematic importance may be compared with the pores, and their occurrence shows a similar lack of constancy. From their shape and structure we can distinguish between jointed and nnjointed, single and branched spines. The joints seem only to be a practical arrangement, to enable longer spines to better resist pressure and blows, and as a rule consist in the spine at the proximal part being I'lirnislied with a chitinized belt which gives it a certain flexibility. In specially long spines such joints may be repeated up to nine limes, and such articulated spines have thus a certain resemblance to the antenna' of many insects. They occur rather seldom and are only found in a number of Retepora species, in Escharello diapluina (Fl. XVII, fig. 1 a) as also in the species of the genus Exochella. All short spines are on llie oilier liarxl nn- jointed. More or less strongly branched spines are also very rare and can be found in single, double or still larger numbers in various families and genera.
79
In the genus Electra the median acropetal spine is much branched in E. helliila, while the peculiar unilateral covering spine, which appears in the family Scrupo- cellariidae is branched in a number of species, as in Scriipocellaria reptans and Menipea (uulcala. Further, branched oral and marginal spines appear in larger or smaller nundier in Mcnihrdniporina cornujcra, M. protecla, in several varieties of Microporelld Maliisi, in two species of the genus Clutpeiid {(I. (iiiniiliis and C. cerincornis), in Hiunlupora radicifcra and in some Species of the family Cribrilini- dne. The differences mentioned in the shape of the spine have, as will be seen from the given examples, generally a very slight systematic importance, and are not even always an expression for a difference of species, hi the same way as there is hardly any family or genus, except those very poor in species, in which all the members have spines, so there are hardly many species, in wliich the number of spines is constant, and in many cases the variation is very consider- able. We may give here a few instances of the variation in number of the spines in genus and species, hi Smitlina the number varies between 0 and 8, in Escha- rvlUi between 0 and 10, in Chaperia between 0 and 8 and in Callopora between 0 and 13. hi Electra inonostacljiis the number varies between 1 and 18, and even the one is not always present, in E. pilosa between 4 and 12, in Callopora liiiealu between B and 12, and in Biujulu Murraijana between 3 and 8. hi discussing the systematic importance of the spines, we must still notice that the family Cribri- linidae is based solely on the mutual relation of the marginal spines, and that a plate-shaped or branched covering spine only appears in the family Scrupocellarii- dae. To this we must still add that this spine is far from being found in all the species of the family, and that the family Cribrilinidae is undoubtedly not a natural one. hi contrast to the generally great inconstancy and variation of the spines, it may be mentioned that marginal spines are always lacking in numer- ous families, which are mostly rich in species, e. g. Farciniinariidae, Cellulariidae, Sleiianopori'lUdne, Thalamoporellidae, Adeonidni-, Calcnariidae, C.clleporidae, Hippo- Ihuidae, Myiiozoidae and Tubucclbiriidae.
Finally, we may briefly refer to a new Callopora species, from the F'ieroes, which apparently shows the largest amount of variations in the numtjer, struc- ture and mutual relation of the spines, which have yet been found in any Bripzoa. While some zoa'cia only have 4 short spines, others have a veiy varying number of longer ones, which sometimes have the same breadth in their whole length, sometimes the tip expanded or bifurcated. These longer spines in more or fewer zooecia may be united with one another to form a cover, pierced by transver.se furrows, just as we lind in the species of the genus Membraiiiporelld.
The primary aperture. In a nundier of species we meet two ditferenl forms
80
of zooecial apertures, and most of these cases appear in ocecium-bearing species, the ocecium-bearing zoctcia liaving anotlier form of the aperture from the others. rThis condition occurs for example in most species of llie family Catendriidae, the species of Ihe genus Hippolhou, in (UihriliiKi clithridiatd Waters, '■Schizoiiorclht' filucincta Rss., ^Sch." siibinimersa Mac Gill, Scli. spomjitefi Pall, » Lepral ia -^ bislaln Waters, etc. We also find two different forms of zooecial aperture in a smaller number of species which have no ocrcia, for instance in a number of Stegano- porelUi species, in Eiithyris obtecta, Eiith. cUithritla and ■^Lepraluf depressa. Apart from these cases, the form of the aperture is constant within the same colony, and in the main constant within the species, though now and tJien it may show distinct variations in colonies from different places. This last condition is found for example in Scluzojiorelhi sponyitcs (PI. XVIII, fig. 4 c, d). On the other hand, the form of the aperture may have a rather different character in species, be- longing to the same natural genus, and we may mention here some examples. In species of the genus Thcdanwporclht (Pis. VI, VI a, VI b, VI c) we frecjuently find a more or less sharply marked, wider or narrower, roimded sinus, but it is at times so faintly marked, that the aperture becomes irregularly circular and in a few species it is provided with a straight or almost straight proximal edge: . Within the genus Haswellia an oral sinus is lacking in H. yracilis (PI. XVI, fig. 1 b), while it is distinctly developed in the other species (PI. XVI, fig. 2 b), and there is a sinus in Exochella tricmpin (PI. XVII, fig. 9 b), which is wanting in E. longi- rostris (PI. XVII, fig. 6 b). The form of the aperture also undergoes a somewhat considerable variation within the genus Sniittina, as it sometimes has a more or less distinctly rounded sinus, sometimes is irregularly circular or quadrangularly rounded.
While the examples mentioned, which might easily be added to, make it al- ready very doubtful, if it is right to attach the great systematic importance to the form of the aperture, which SinilL, Hincks and other authors do, this doubt is further strengthened when we examine the whole extent of the dilferences, which the form of the aperture can [)resent within the (^heilostome Bnjozoa, and the appearence of the.se different forms of the aperture within a series of natural families.
We can refer the numerous forms of aperture to two diiTerenl types, which however in reality grade evenly into one another, and which we may call the »holostonie« and the »schizostome«. The holostome aperture may have the form of one continuous line of different shape (circular, oval, transversely o\al), in which ca.se the boundary between the distal (the anter) and the proximal (the jjoster) part of the edge of the aperture cannot be defined by the aid of the form of the
81
aperture itself but either by the aid of hinge-leelh, or where such are missing by the points of suspension of tlic operculum. Again, the edge of the aperture is divided naturally into two different portions, a distal and a proximal, which meet at an angle on each side. The distal portion then generally forms a larger, more convex curve, the lateral parts of which may be parallel, converging or diverging, while in the proximal, smaller j)ortion we find all possible conditions between a curve and a straight line. A review of a large series of holoslome apertures shows us that forms of apertures such as the circular, the elliptic, the semicircular, etc. are mutually connected by such a number of transitions, that it is quite hopeless to base a systematic division only on the form of the primary aperture. In his well-known Monograph Hincks' uses the following designations for the form of the aperture in the holostome genera described by him: "semi- circular« (Chorizopora, Microporella, I'oielln), more or less semicircular* (Phylactella), ^semicircular or suborbicular< (Micropora), »semicircular or semielliptical« (Reteporci), »suborbicular or semicircular (Miicionelld), suborbicular (Smitli(i), suborbicular or subquadrangular<^ (Ufuboiu'lhi), orbicular or ranging from semicircular to semi- elliptical« (PalmiceUaria). The designation >.semicircular« is thus used to charac- terize the form of the aperture in eight of the ten genera here mentioned, either alone or in connection with the designations: 'suborbiculars semielliptical and »subquadrangular«, of which the first appears in the diagnosis of four, the second of two genera. We can easily see that the differences in the form of the aperture, which Hincks put down for the genera mentioned, are loo vague and indefinite to be of any use in their distinction.
hi contrast to the holostome the schizostome aperture has on its proximal edge a more or less deep sinus. If we take our starting point from a form such as Arlbropoma (Scliizoporella) Cecili or Schizoporclhi sjionyiles, in which the sinus is very narrow, almost slit like, and if we imagine this as gradually widening on both sides, we will have a series of apertures with varying breadth of sinus until at last this disappears, because its sides run into the lateral edges of the aperture. On further extension the sinus becomes wider than the rest of the ajuMture, as it is in some of the species referred to the genus Lepnilui. Still this picture only gives us a fractional part of the variations, which the schizostome aperture in reality presents, because a similar variation lakes place ])artly in the depth or height of the sinus partly in the shape of its proximal rim, which uuiy some- times be straight and sometinu-s uu)re or less curved. It is clear, IIkiI the schizo- stome aperture otTers a far greater possibility for variations lii;in the holostome,
') 22.
82
because besides Ihe variation in the distal part or the aperture, we also have the possibility for a so to spealv endless variation in the extent and shaj)e of the sinus. That such a variation is not merely an abstract thought but really exists, will be admitted by all who on the one hand have examined large (pianlities of Bryozoa, and at the same lime also have studied the considerable literature on this subject. The majority of those species, which have a schi/oslome aperture are referred by Hi neks and later writers to the two genera SchizoporelUt and Lepraliar Though Hincks considers them to belong to two distinct families, it is in many cases a matter of guesswork, whether to class a species to one of Ihe genera or to the other, because they can only be distinguished by a dilVerence in the shape of the aperture. Yet the diagnoses of the two genera seem to be quite ditTerenl, as a Schizoporelld aperture is considered to have a sinus on the proximal edge, but Lepidlia a horseshoe-shaped aperture, contracted at the sides. Since, however, such a proximal part of the aperture, so contracted, can in reality be regarded as a sinus the difference between the two kinds of apertures is reduced to a difference in the width of the sinus, and species with a narrow sinus have thus been referred to Scluzoporella, and those with a wide sinus to Lepralia. The result of Ibis consideration is then thai the shape of the primary aperture, on account of the practically endless variations to which it is subject in the Cheilo- stome Bnjozoa, cannot have any great systematic importance, and that it can at the very most only be used as a more or less constant, auxiliary character in Ihe diagnosis of the genera.
We arrive at the same result on considering the question from another point of view. If we examine the aperture in a large number of forms belonging to a series of families, we find that cjuite corresponding forms of aperture, holoslome as well as schizostome, reappear in all families which are rich in species, and we may thus draw the conclu.sion, that the.se different forms of aperture in each of these families have ari.sen inde|)en(lently. To mention some of the most |)romi- nent forms of aperture, we lind for instance an aperture with a sinus in the following families: Cribrilinidae (e. g. in Cribrilinu clUhridiata Waters), Thalamo- porelliddc. Miiriozoiihic, Eschnrellidde (in Scluzoporella and Kscluiriiui), Snnlliitidae (Sinitliiia linearis, S. porifera etc.), Hippothoidae (Hippnlhoa, Triiposleija), Adeoiiidac (.several Adeonella species), Releporidae (lielcpora iiiiperati. Ret. simiosa, Rhiincho- pora, »Sc/H'ro/)0/-e//rt« scintillans, etc.), Catenariidac {Cjdpidiiim, CAavipurella, Ilincks- iella, etc.), Eiitbijridae (Urceolipora nana) and Celleporidae. A .semicircular a|)ertnrc with a simple operculum, which is furnished with a straight or slightly curved proximal edge, is found further in the following families: 'rhalanioparcllidae (Tlud. expansa, Tlud. Jervoisi), Microporidac. Cellnlariidai; Escharelliilae (Micropordla,
83
Inuersiiila), Hippothoidae (Haplopoma, Chorizopora), Adeonidae (Adeonellopsis) and Onchoporidae (Onchopora).
Besides the shape of the aperture we must also consider its teetli-shaped projections, and I have already called attention to the fact, that we can distin- guish between hinge-teeth, supporting teeth, and such protecting teeth as are placed outside the operculum. Teeth-like projections of different kinds are occa- sionally used by different writers, e. g. Smitt, Hincks, Waters, JuUien, as generic or family characters, and JuUien' has for instance founded a family Stnittiddc merely on the presence of a median tooth (lyrula) and two side-leeth (cardellae). To judge from the name he gives the two side-teeth (cardellae, from cardo a hinge), we would imagine (hat he regarded them as hinge-teelh, but in Exochelld they belong to the jteristome, and may even join togethei- with one another or with the median tooth (K.v. lonyirostris). For the rest the author writes regarding all the three teeth: »c'es( Ic (levelloppemenl du jeune peristome qui contribue a former la lyrula et les cardelles dans la famillc des Smittiddei. There is no reason for attaching much systematic importance to these teeth-like projections, and they can at most be used as more or less constant auxiliary characters, particularly in the diagnosis of genera. Hinge-teeth seem to appear constantly, but in somewhat varying shape in the genus Smittina and to be wanting in the genus Discopora. In the genus Tludamnporellri tliey are very di- stinct and well developed in a series of species, whilst in other species they are very slightly develo[)ed or absent, ami Ihey seem to ajjpear very seldom in the genus Holopordla. Supporting teeth seem to appear conslanliy in the genus Cellularia, but as already mentioned they vary in shape and number. The median tooth, to which the greatest importance has been attached, seems to appear within most families which are rich in species, but in families which are only tolerably rich in s|)ecies, it never seems to be constant, and it is not even always constant within the species. It is found in the family lisclmrclliddr. in most species ol the genus Escharella, in the family Discoporidae e. g. in Discopora pcwonclUt, I). sc(d>r(i and D. plicaUi, in the family Petraliidae e. g. in Petralin casla- neii and /-•. hisiiuicdd, in the family UolopovvUiddc e. g. in Holoporclla Iridcniiciihda, in the family Relefxtridae e. g. in Retepord noude ZeUmdide, in the family Adeonidae e. g. in Brdcchridijid piirifonnis, and in llie family Crihriliniilde in a variety of the fossil Mciubrdiiijiorelld crcjiiduld Hog.
As examples of species, in which the median tooth is sometimes present, sometimes absent, we may mention l)esiilcs the last-menlioned : I'luclla coiniircssd,
■1
' 45, p. 52.
84
P. coiuinixi, Smittina palincila, Discopora scabra and D. plicata. In llie two lasl- nienlioned species there may even in lliis regard l)e a dilTerence between the single zoa-cia in the colony.
In connection with the aperture, we have still to nienlion as systematic character the i)reviously discussed vestibular arch, which seems lo appear con- stantly in the family Rete})orid(ie and in most genera of the family EscIvircUidde.
The peristome or the secundary ai)erture, which forms a more or less perfect vestibulum lo the true or primary aperture, appears only within the Ascophora and is even within this division represented in a very irregular way, as it may sometimes be absent in whole families (Catenariiddc, Pdidliuldc. Holoporrllidae), or genera {MicroporclUt), whilst in others it appears to a very variable extent. A peristome may sometimes be developed round the whole circuit of the primary aperture (^Lcpralid" cfinthdrifonnis, the species of the genera Hnswellia and Tuhii- cvlliirid. liclcpora prctiiuild KirU, etc.), sometimes over only a larger or smaller portion of this, being somelimes interrupted distally (»P/ii//«c/e//a« hdirosa, »7-'/i.« cnlldris, "Schizoporelki- drnudd Yar.), or [)roximally (many species of Smittiiid and Retepord). In some cases it is formed by continued growth of the edge of the primary aperture ("Leprdlid P(dl(isidiui Xiw, »Lep.<^ cdulhnrijoimis, Esclvninii sim- plex), whilst in other cases it forms a wall outside this rim ( Phi]ldclelld< lahrosd, »Pli.' colhtris, "Scl}iz.« drmdki Var). It may be low. circular (Escluirinn siiuple.v). funnel-shaped ('Lep.< canllidrij'orinis), or tube-shajjed (Retepord pectinala, Ret. phoeniced, Eschnreltd spinosissititd, Phijlacleltd' (/eoiuctrica) and in a number of cases provided with a pore on the frontal wall. It is occasionally furnished wilh teeth-like projections, which in number and position are like those, which in certain genera belong to the primary aperture. This applies for example to the genus Exochelld and certain species of the genus Eschdrnides.
As the peristome is often very obvious il is easily undersh)od why il has in many cases been used as a systematic character at the cost of others more im- portant, but less prominent, and in Hincks' great work the following genera are besides the family Porinidde entirely or chielly based on the structure of the peristome, namely Poriiui, Ldijempora, Schizotheai, Porelld. Eschdrnides, Snullid. PluildctcUd, Mucronelld, Palinicelldiid and RliiinchoptH^. Of these genera I am onlv able to retain Porelld, in the limitation given by Hincks.
In discussing the cpiestion of the systematic importance of the peristome, we may first call attention to the fact that the same peristome forms recur within a series of widely dilferent families and genera. We thus find a collar-shaped I)eristome. i'urnishcd wilh a frontal incision in many members of the familv
85.
Ret('lMri(l(te, in a series ol' species of Ihe genus Smitliiiu, in PorclUi coiujiressu and Discopuni Sarsi. A shorter or longer liibe-shapeil peristome willi a pore on tlie frontal wall is found in the genera Adeonclhi, Hasivcllid and Ttihiicellaria, in cer- tain Retepora species (R. cellnlosa, R. Coiichi, R. complanata etc.). in Tessaradonui bovealis, 'Porinao tiibiilosa, Sinittina Lanshorovi, var. persoiiata), whilst a long tube-shaped peristome without pores is found in certain Retepora forms {R. pecli- naUi, R. phoenicea), in certain Cellepora forms (Cellepora tiibulosa, C. bicornis), Lekijthoj)(>r(t hi/strix, TPhijladellai^ geometrica etc. Next, I would point out, as a general result of my investigations on this point, that the peristome in many cases is very inconstant within the genus (e. g. : in the genera Escharella, Sinittina, Discopora, Petralia, Cellepora, etc.), and Hi neks even mentions a series of cases where the peristome in the same sjiecies may sometimes he present, sometimes absent, which for example is the case in '■Lepralia- Pallasiana, Sniiltina trispino.sa and Escharina Diitertrei. Whilst the above-mentioned small peristomial teeth are found constantly in the small genus K.vochella, their appearance is very incon- stant in the genus Escharoides, and on the whole like Waters I cannot attach very great importance to the peristome, which however does not exclude the possibility that ils apperancc may be constant in a series of genera, e. g. in Adeonella, Hasuwllia and Tiibiicellariu.
The operculum. As all that has been said regarding the systematic impor- tance of the form of the aperture, also holds good as a rule for the form of the operculum, we may here merely take note of the other ditTerences, which a])pear in its structure. As already mentioned, we are able from the difierent relations of the operculum to the frontal cover and the compensation-sac to distinguish between an opercular valve, a simple and a compound operculum. These dille- rences have however only partially a systematic importance. We have a series of examples of the fact that an opercular valve and a sim|)le o[)erculum may appear within the same genus: e. g. in Sleganoporelln and 'I'ludamoporetld, and especially in the last-mentioned we find a series of intermediate forms between the two kinds of operculum. We have other examples in the i)reviously men- tioned species of Caberea and Scruj)ocell(tria, in which the |))esence of a simple operculum seems to be dependent on the strong development of the covering spine. That an opercular valve and a compound operculum can appear in the same genus, we have examples in the genera Adeona, Porella, Escharella, Escha- roides, Snuttina, Holoporella and Chaperia. Whilst for example we as a rule find a compound operculum in Porella and Adeona, there is an opercular valve in Porella la'vis and Adeona violaceu, and while there is generally an opercular
8(>
valve in EscbareUu unci Escharoides we liiul a well-chilinized compound oper- culum in Escharella polita and Escharoides saurocjlossa.
But the contrast between a simple and a compound operculum is of greater systematic importance, and it seems as a rule to be an expression for a generic difference. We find a simple operculum within a series of Ascophore families {Escharellidae, Hippolhoidne, Onchoporidue, Adeonidae'), and it is generally accom- panied by a different mode of opening of the compensation-sac, which in these forms with a simple operculum with a single exception (Chorizopora), opens out through a median pore (see pag. 32). In spite of the above examples of varia- tion, llie structure of the operculum seems as a rule to show more constancy within the genus than for instance the shape of the aperture and the peristome and must he regarded as one of the best distinguishing characters. Referring for the rest to the separate families, we may just mention as examples that while a well-chitinized, compound operculum is found in Schizoporelln, Porella, Cellepora and Adeono, a membranous operculum, which is not separated from the compensation-sac, is the rule in the genera Escliarella, Escharoides and Discopora. The mode of attachment of the occlusor muscles seems also to be rather constant within the genus, and we niaj' cite as examples that there are special muscular ridges or muscular processes in the genera Porella, Escharina and Microporella, while Schizoporella, Cellepora, Arthropoma and Conescharellina have muscular dots.
The rosette-plates are interesting examples of a structural feature which, though subjected in a number of cases to considerable variation within the genus, and even within the species, proves in most cases to be constant, not only within the genus, but also within the family. It is specially the rosette-plates of the lateral walls, liowever, which show this constancy, as those which appear on the distal wall in many cases show great variation, and we may cite the rosette- plates on the distal wall of Membranipora membranacea as a very ])ronounced example of such a variation ([>. 24). Referring for the rest to the diagnoses of the separate families and genera, we may here cite the following families and h\ genera, partly very rich in species, in which the rosette-plates of the lateral
walls especially show eitlier perfect constancy in structure and ap])earance, or only a small degree of variation, namely: Farciminariidae, Scriipocellariidae, Bi- cellariidae, Cellulariidav, Stcfiaiio/iorcllidae, Thalamoporellidae, Adconidae, lieteporidae, Catenariidae, HippaUundae, (lelleporidae, Holoporellidae, Onchoporidae, Conescharelli-
' see pag. 38.
87
nidae, Mijriozoidde, Escliarella, Escharuide.s, Pori'lla, Omjchocclhi and Calloporti. On the other hand, the rosette-plates show variations in the families Fhislridae, Membraniporidae, Cribriliiiidae and Micioporidae, l)ut in slill higher degree in the genera Schizoporella and Sniittiiia. hi these some species have single-pored, others multiporous, and again others mixed rosette-jilates, and colonies from different localities may show a distinct difference in the number of pores in the rosette- plates e. g. in Schizop. unicornis, Sch. sanguinea and Sch. longirostris.
Synopsis of the Fa mil
of Cheilostomatous Biyozoa licnlcn
ies and Genera
I of in llu- present work.
Subordo Anasca.
1. Division: Malacostega. f '' ' j, -u F;im. Aeteidae: Gen. Aelea. rf>M^ Fani. BiceUaiiidae: Gen. l)imor))ho- zoiim n. g., Biujiila Oken, Stolo- nella Hincks, lieania Johnst., Hiantopora Mac Gill., Chaperia Jullicii, Petalosleifux n. i^., Hdlojiliiht Busk, Motdinia Flcm., Gemellaria Sav., Hrctlici Dyster, Cornucopina n. g., Didijmut Busk, Eiicralea Lamoiir., Dinw- topia Busk, Kincloskids Kor- Dan., liirellfirid Blainv., Btign- larid n. g., Bicclhirina n. g., Walersiii n. g., Deiidrobeania n. g. Fani. FarciniiiKiriidac: Gen. Farciiui- iKirid Husk, Columwirin n. g., Nellia Busk. ' * Fam. Flastridae: Gen. Fliislrn L., Sdisilhistra Jullien, Kenelhi n. g., Relifluslra n. g., Spirahi- ria Busk, Heterojlnslid n. num.
Subordo Ascophora. "^
Fam. Calenariidae: Scnticella n. g., Crihricelld n. g., Costicella n. g., Claviporella Mac Gill., Pterocella n. g., Calpidium Busk, Hiiicksielld n. g., 6'o/p- /mr;V( Sav., Stro])hipora Mac Gill.
Fam. Onchoporidde: Gen. ddweUid Wyv. Th., Onchopord liusk, Onchoporelld Busk, Oncho- linroides Ortin.
Fam. Eiitliyruiddc: (Jen. Knlluiniidcs Harmer.
Fam. Fiitliyridde: Gen. FncoUpord Mac Gill., Eulhijris Hincks, PIcnrotoichiis n. g.
Fam. Sdi'ignfit'llidae n. f . : Gen. .SV/- I'ignijella n. g., Hcdijsisis Nor- nuin.
Fam. Hippothoidac: Gen. flippnlluxi Lamour., Chorizopoin Hincks, Hdplopoma n. g., Tryposfega n. g.
l-X"^
89
\
(Anasca). yO Fain. Scriiimcclldriidae: Gen. Scriipo- celluria Van Ben., Canda La- niour., Bugiilojisis Verrill, Ho- plilella n. g., Rhabdozoiim Hincks, Caherea Lainour., C(i- bvriellu n. g., Menipca La- mour. ,m3 Fain. Memhraniporidae: Gen. Meiu- branipora L., Electra Lamoiir., Cidlopora (Gray) Norman, Metjaporu Hincks, Tef/ella n. g., Caleschara Mac Gill., Oiiijcho- cella Jullien, Cnpularia La- moiir., Lunularia IJusk, Sele- n(tri(t Busk. Fain. Cribrilinidae : Gen. Meiubidiii- porella Hinclvs, Cribrilina Gray, Piu'lliiKi .lullien, Fiipilind Jul- lien, Aspidclecii-d n. g., Aracli- nopiisia Jullien.
2. Division: Coiloslega. ^ ic(
u J Fain. Microporidne: Gen. Micropora Gray, Macropora Mac Gill., Fleniiseptella n. g., Forainin- ella n. g., Calpcnsia Jullien.
f.W" Group Tublfera:
Fain. Stc(jaiwporellid(ie: Gen. Slccjd- I noporella Smitt., Siphonopo-
rella Hincks. Fain. Aspidnstontidae j;^ ^: Gen. Aspidosloma Hincks, Labinpora n. g., Crateropora n. g. Fain. Th(d(imop()renidae.pGen. Thala- vL moporelln Hincks.
,«\)Fani. Chlidnniidnc : Gen. Chlidonia f Sav.
(Ascophora).
Fain. Adeonidac: Gen. Adeona La- inour., Adeonellopsis Mac Gill., Adeonelki Busk, Bracebridgia Mac Gill.
Fain. Retepovidav : Gen. Retepnra Lnperato s. ext., Rluinclw- pora Hincks. P'' Fam. Myriozoidae : Gen. Leiescharn Sars, Mijviozonm Donali, //o,s- wellia Busk, Gephijvophora Busk.
I'";un. Sclciiidoniiditc: Gen. Sclero- doniiis n. g., Tessdrddomci Norman.
Fam. Tubmrlhiriiddc: Gen. Tnbu- ccllnrid iVOrh. /rnbij)(>iclla n.g.
Fain. Conescharellinidae n. f. : Gen. Conescharellind d'Orb., Bipovd Whitel., FIdbellipora d'Orb.
Fam. Liriozoidae: Gen. Liriozoa Ellis-Sol., Geinellipord Smitt.
Fam. Lekijthoporidae n. f. : Gen. Leki/thopord Mac Gill.
Fam. Eiirystomellidae n. 1".: Gen. Eiirystomella n. g.
Fam. Escharellidae n. 1'. : Gen. Eschn- rella Gray, Anarthropord Smitt, Invevsiula Jullien, Escharoides Milne Edw., ZJ.ro- chelld Jullien, Schizoporella Hincks, Escluirina Gray, Mi- croporella Hincks, Artliro- poma n. g., Eniballotheca n. g., Cyclicopord Hincks.
Fam. Smittiniddc: Gen. Porella (Gray) Hincks, Smittina Nor- man (n. nom.), Discopora Lam.
.^
(Anasca). Fam. Aliishliiddc u. (limn Busk.
90
1. ; (k'li. Alijsi-
^,~ -
3. Division: Pseiuhslega.
Fain. Mviiihrdnicelldiiitlde n. I'.: Gen.
Membranicelhiria n. g. Fam. Celliihiriiilde: Gen. Cellidaria
Pallas.
'V
(Ascophora).
Fam. (lellcjMriddc: Gen. Cellepoia
L., Siniopdtd n. g. Fam. HoloporeUidac n. f. : Gen.
lloloporeUa Waters. Fam. Pctraliidae n. f. : Gen. Petra-
lia Mac Gill. Fam. Hippoporinidae n. f. : Gen.
Cheilopora n. g., Hippopodina
Systematic Part.
Order Cheilostomata.
The zoacia, to a larger or smaller extent calcified, as a rule furnished with an operculum (except Bugula). There can he found four different forms of indi- viduals: uulozoa-cia, heterozooecia, gonozoa-cia and kenozooccia, and in many cases the eggs are matured in special, outer or inner, calcareous marsupia, the so-called ooecia. The separating walls between the individual zocecia are furnished with rosette-plates, and in colonies consisting of more rows we can as a rule distin- guish between a horizontal or oblique distal wall and vertical lateral walls, which are most frequently independent. More rarely a lateral wall is common to two adjoining zocecia, which on the other hand is almost always the case with the distal wall.
Suborder Anasca.
A compensation-sac is wanting, and the frontal wall is either wholly or in part membranaceous, or calcareous, depressed and surrounded by raised margins. In the heterozoa'cia the opercular and the subopercular areas are as a rule not separated by a continous calcareous bar, but only partially by the hinge-teeth of the operculum.
1st Division: iVlalacostega.
The individual zoa-cia are plainly marked olf on the surface of the colony. The frontal wall quite or partially uncalcified and the operculum as a rule a membranous valve, the rim of which is chitinized, but which proximally passes over into the frontal membrane.
92 Family: Aeteidae.
(I'l. VI c, liji;S. li ;i-(i (1).
The zoa'via, wliicli liavc no spines and the calcareous wall of wliicli is (icnscly covered willi j)oies of dilTerent form, consist of Iwo portions inclined towards one another at an angle, the lower of which is as a rule decumbent, adherent, while the upper, mostly tube-shaped part is provided at its expanded end with a small membranous frontal area. No cryplocyst. The diajjhragm has a structure similar lo thai in the Ctenoslonicita. The heterozoivcia and (mvcui wanting. The distal wall furnished with a row of uniporons rosette-plates. The colony creeping, forming a meshwork of single rows of zoa-cia, from which free in-anches some- times issue.
The partly thin, thread-shaped adherent part, from which the free upright part of the zocecia arises, is by Flincks compared lo a stolon bul this name can only be used for a basal portion, consisting of kenozocrcia, as found within the order Ctenostoniatct in the families Vesiciihtriklae, Trilicellidae, Valkeriidae and Mimosellidae and within the Cheilostomcitd in the genera Chlidonia, Liriozoa and Stirpaiid. In .4e/('a the whole colony is built up by autozoa'cia, and the fact, that the proximal part of the zoa?cium is thin and uuich elongated, does not entitle us to sj)eak of a stolon in these sj)ecies any more than in the species, which Hincks refers to the genus Hippolhou. The adherent parts of two successive zooecia are separated by a wall, which in Aetea dilatata is furnished with a row of 7 uniporous rosette-plates, and a similar separating wall is found everywhere, where one zo(]eciuni issues from another. In Aetea triincnta according to Hincks new free zooecia maj' issue from the basal side of the ascending [)arl of the zooecium. The calcareous wall of the zooccium is richly furnished with ])ores, which in dilferent species can appear in diderenl ways. Thus, while the whole calcareous surface in Aetea dilatata is furnished with round jjores, the form of the pores varies in many other species at different places. For example, the distal part of the zoa'cium in Aetea aiuiiiina and also the broadest part of the adherent portion are furnished with small round or oval pores. In the narrower jiart of the adherent portion they fuse together to longer, slit-like spots (fig. (id), and in the largest part of the ascending portion (fig. 6 c) they become continuous, ring-shaped interruptions, and therefore the calcareous portions ai)pear as a row of free rings situated above each other, which can be isolated without great diffi- culty. Sometimes however we find a short connecting branch between two succes- sive rings, or a bifurcation of a single ring. Waters' has found an egg enclosed
' 111, p. 5, Fl. I, ligs. 1—0.
93
ill a spherical, transparent body near llie lip of the basal side of the ascending part of the zoa-ciuni in a large numi)er of specimens of Acted angiiina, and con- siders this to be an ooecium. The great transparency of this little globe, which has enal)le(i Waters to count the cell-divisions of the egg, seems to indicate, tlial it is not calcareous, and this fact in connection with its for an oa'cium, very unusual position on the l)asal side of the zoa'cium, speaks decidedly against the ocecial nature of these globes. I must therefore regard the supjiosed ovicellular wall only as a shell membrane surrounding the egg.
Smitt' has already called attention to Ihe great agreement between the members of this family and the Ctenostoiiuitd; but when he specially compares Acted with the family Vesiciilariidae, we must remark, that this genus shows a much greater agreement with the families Ciitindroeciiddc and Victoretlidae, in which the zooecium according to Hincks also consists of an adherent and an ascending j)orlion, while they have no real stolon. In all Ctenostome families, where the zorecia issue from a stem or stolon consisting of kenozooecia, the zooecia die away and can be renewed, whilst such a renewal does not take place where there is no stolon, as in the two above-mentioned families, and according to this, the peduncles in Tvitkelln must belong to the stolon and not to the individual zooecia. Smitt' has also called attention to the fact that Acted, in the cylindrical form of the zooecia and the rich development of pores, shows agreement with the Cijclostomatd, and he imagines the possibility that the latter may have had a Ctenostome origin. Without entering further into this question I wish only to point out in this connection that in the Cyclostome species Stomatopord <idltkd d'Orb. - the zooe- cium, as in Aetnu consists of a decumbent and an ascending part. On the other hand, the agreement which an Acted shows with such a species as ■Mncroncl!a< cotlmnnca Kirk, is of (juite a superficial nature, as the ascending tube-shaped portion in the last-mentioned species is only a periston! and cannot therefore be compared with the ascending portion in an Acted, which has an operculum near the tip.
Family Bicellariidae.
Kncnitiiddc Hincks, Notainiidae Hincks. (Pis. III-V).
The zod'cid as a rule slightly calcified and in most cases with a large mem- branous frontal area. Where a distal wall is developed (wanting in Hcduia and Stnlonclla) it is nmre or less ascending and its basal edge is then placed more or
' 99 a, p. 46U. " 8(5, VI. 7.59, ligs. 1—3.
94
less proximally on the basal surface of Ihc zooecium. The lateral walls always independent, and each provided with 1 (rarely with 2) multiporous rosette-plate, which is often partially uncalcified. The avictilaria when present dependent, most frequently capitate, pedunculate, freely movable, more rarelj' sessile and in that case often extremely long and slender. The iMvcia as a rule hyperstomial, free, more rarely endozooecial and then as a rule covered by kenozo(i>cia. The colonies free or creeping, generally branched ami frecjuently provided with radical fibres. • With a few exceptions (e. g. Hiantopora and Cbaperia) the calcification in this famil}' is very feeble, and the least calcified Cheilostoniala known are undoulitedly the Beania species, of which some contain so little calcareous material that it is only by using hydrochloric acid that we can make sure that there is any calci- tication at all in their walls. Whilst the whole frontal wall in the Beania species, in Dimorphozoiim nohile and Watersia mililnris. is membranous, in most members of the family a larger or smaller portion of it is calcified and forms a gymnocyst, which may sometimes, for instance in (icmcllaria loriatta and certain Corniicopinu species, occupy two-thirds or three-fourths of the whole length of the zoa'cium. From this gymnocyst in older zooecia there arises not so seldom a small secund- ary cryptocyst (e. g. in Duhjiiua simplex, Geiiiellaria loricala, Deiulrobeania Miirnnj- and). Except for the species of the genus Beania in which the individual zocecia are connected by cylindrical tubes, two zoo'cia in the same longitudinal row are in all other cases connected by a distal wall, which is always more or less ascending from the basal towards the front wall so that the distal end of the lower zocjecium projects more or less over the j)roximal end of the zocecium above. It is usually furnished with a number of uniporous, more seldom with one or two multi- porous, rosette-plates and not rarely {Bmjula, Halophila, Didijmia, Bicellariu, Bicel- larina, Bnc/nlaria) the basal edge shows a peculiar angular bending (PI. Ill, figs. 1 c, 2(1, PI. V, ligs. la, 2 1)). Each lateral wall is as a rule provided with 1 or rarely with 2 multi])oious rosette-plates. Except for the pore-ring they are as a rule membranous, and it is therefore difficult to decide, from spirit-material, whether they ai'e uni- or mulliporous. In all cases where they are calcareous, e. g. in Dendrobeania Miirraijana, l)in}(irj>hi>zount nohile, Biujularid dissiniilis etc., they are however multiporous. Whilst the dependent avicularia in most Cheilo- stonuitd attain their greatest breadth where they are fixed to the zoa'cium, most avicularia in this family are provided with a shorter or longer movable peduncle or the ])roximal part of the avicularian chamber is slender pedunculiform. While the first have tlie j)eculiar resemblance to a bird's head wliicli has given rise to the name > aviculariiim» the others which increase gradually in breadth toward the distal end have been described as trumpet-shaped. (>ommon sessile avicularia
95
appear however in Hianlopora, RiujuUirUi (PI. V, fig. 2 a), Petalosiegiis (PI- IX, figs. 8 a, 8 b) and .sometimes in Chai>eri<t. The ooecia are as a rule hyi)erstomiai, and might be considered as free, i)ecause the endoorecium only has a small portion of its basal wall in common with the frontal wall of the zooecium. Whilst the endoooecium is always calcareous, the ectoooecium may be calcified completely (Bicellaria ciliat(i) or almost completely (Dimetopia corniita), or some- limes quite or partially uncalcified (Dcndrobeania Miirrdijtina. BiKjnlaria dissimHis, etc.). In a smaller number of cases Ihc o(rcia are immersed either in kenozoii-cia or in ordinary zocecia (yBugiila^ inirdhilis). With the exception of most Chaperia species and of 'Membrnniporaf CarU'ri\ which on account of its pedunculate, capitate avicularia must certainly be referred to this family, the colonies are never incrusting and appear in a greater variety of forms of growth than in any other family of the CljeilDstonuitd. Apart from such genera as GemelUtria, Notamia and Siinnotum, in which the colonies may be considered as two-layered, colonies with two layers are only found in Wdtersia militaris and Bimorphozoiim nohile. Radical fibres appear in most genera and in very different ways (see Ihe synopsis of the genera).
This family, like the Aeteidae, presents a series of points of contact with the Ctenostoimtid, and forms so to speak a connecting link between these and the Cheiloslonuttd. This is nowhere more prominent than in the peculiar dimori)hism in Dimorphozoiim nobile (PI. IV, ligs. 1 a— 1 e), as the zou>cia in the one layer of the colony are built in quite the same way as in an Alcynnidiiwi, whilst in the opposite layer they possess an operculum, avicularia and ocecia. For the rest, however, the diaphragm in these zotecia seems to be Ctenostome-like. We should also remember that an operculum is absent in species of the genus Bmjiiki, as also that the diaphragm in Eiicrdled cheMd is said lo be built in the same way as in the Ctenostonuitd. The generally slight calcification also agrees with this view, and finally a series of forms in this family shows quite similar modes of connection between the zoa'cia as those we know in the majority of the Cfeno- stomdld. Thus, Bednia corresponds in this regard with the Ctenostome genera Ardchnidium and Biiskid, whilst the stolon or stem, which consists of kenozoiecia and which is widely distributed in the Ctenostomatd, is again found in ^Bkelldvid' (jldbi-d, Biujidd (Stirpdrid) Hdddoni and B. (Stirpdid) cdrdibicd.
When Busk, Hincks and other writers refer a number of genera of the family (Eiwrdled, Ccmelldrid, Notdinid, Didijmid, Dimetnpid etc.) lo other families, I lie reason is, thai these writers have laid greater stress on the form of colony
' 'r.i. p. s'i
96
or on the modes of connection of the zoa-cia. In their whole structure these forms undouhledly belong to the family BiceUurwUte. The peculiar contrast in Episto- mia and Sijiiiiotiim^ between the proximal cylindrical and the distal widened portion of the zmecium as well as the possession of |)e(lunculate avicularia, shows that the position of these genera is near lo (lormicopiiui. hi Gemellarid the dislal wall is as in Biu/iilci: angulale and furnished with a series of uniporous roselte- plales. We also find an angular distal wall in Didymia, the oa-cia of wliicli, like those in Einrateo and Coniiicopiiia, are surrounded by kenozooecia, and Dimetopia has like most of the Bicellariidae, free orocia. Finally, I have been obliged to set up new genera for the old F/«s/r«-species, Fl. nohilis, Fl. dissiniilis and Fl. militaris as also for BiujiiUi Mnrraijnna, BicelUiria Alderi and ('.iilewtiia" hicornis. It is however with some doubt that I refer the last sjiecies lo Ihis family.
In the following synopsis of the numerous genera of Ihe family, lo which I have been ijnder the necessity of adding 6 more, I have as main characters in the separation of the genera mainly used diderences in the structure of the zoa'- cia themselves, as e. g. the presence or absence of an operculum, the division of the zooecium in different segments by constrictions, the structure of the dislal wall, and next the differences in the character of the occcia. I have used the piesence or absence of ooecia and avicularia, as well as Ihe dilVerences in the structure of Ihe avicularia, as auxiliary characters.
Synopsis of the Genera.
1) The colony consists of two layers, the zowcia of which are of very different kinds (Ihe zod'cia in one layer are quite uncalcilied, without operculum, in the olher layer they are of the ordinary type; the distal wall consists of a horizonlal. basal iiorlion wilh a mulli- porous roselle-[)late, and of ii fronlal ascending portion; free oa-cia, freely movable avicularia) Diiuorpliozoiim n. g.
1) If the colony consists of two layers, the zocecia of the two layers are of the same kind:
2) Zooecia without operculum; (the edge of the dislal wall is angu- lar; within this a row of single-pored roselte-plales; free Od'cia, freely movable, cai)itate avicularia, radical fdnes issue both from Ihc fVoiilal,
basal and lateral aspects of Ihe colony) limjiiln Okcn (Lev. mod).
2) zocecia wilh an operculum:
' 111, p. 14.
i)7
3) The colonies, which never Iiave a free, upright growth, are ex- clusively attached l)y radical fibres which either issue from a creeping stolon or from the basal surface of the individual zoa?cia:
4) the colony is attached by radical fibres which issue from a creeping stolon; (the zoa-cia which issue separately from the stolon, are furnished with two rows of spines, joined together in pairs and separated
by a single row of transverse slits; no avicularia, no ocrcia. . . StoloneUa Hincks.
4) the colony is attached by radical fibres which issue from the basal surface of the individual zooecia, and these are generally connected with one another by shorter or longer, wider or narrower tubes to form a network with larger or smaller apertures:
5) the zooecia very slightly calcified; the connecting tubes between the individual zooecia distinct; ocEcia wanting; as a rule pedunculate,
freely movable avicidaria lieania Johnston
(Diachoris).
5) The zoa>cia strongly calcified; the connecting tubes between the single zooecia indistinct, broad and short, and only visible from the basal surface; ooecia may be present; sessile avicularia; (from each avicularium issues a spine which is often much branched and may conceal a larger
or smaller portion of the frontal membrane) Hiaiilopora Mac Gillivray.
3) the colonies have a free upright growth or are incrusting.
6) The distal part of the zooecia provided internally with two lateral spaces open towards the frontal surface (sometimes combined to one single, horseshoe-shaped space), formed by two calcareous plates which issue from the lateral walls and converge towards the distal wall; avicularia and free ooecia may be present; the colony incrusting or laminate) Cluipcrin Jul lien.
G) The distal part of the zooecia without lateral spaces:
7) There is a frontal shield, formed by five broad hollow spines lobed at the edge and separated bj' rows of jiores; (a simple com|)lelely chitinized operculum; sessile avicularia) Petalosteyiis nov. gen.
7) No frontal shield:
8) No ocecia :
9) The distal, broader, more or less .symmetrical part of the zoa'cium is separated from a nearly as long, proximal, narrow, cylindrical part by a constriction:
10) The ba.sal edge of the distal wall is angular; no avicularia; a con- striction jusl (listally to the distal wall Halophila Husk (Lev. mod.).
7
98
10) The basal edge of the distal wall not angular; long-slalked
fixed aviculaiia; no constriction dislally to the distal wall... EpisiomUi Fleming.
9) Tlie zott'ciuni not divided into a {)roxinial, narrow cylindiical and a distal wider part (no avicularia).
11) The basal edge of the distal wall angular; (radical fibres issue
from the lateral margin in the proximal jiart of the zoa>cium . . . (leiiicllarid Savigny.
11) The basal edge of the distal wall not angular lirellid Dyster.
8) 0(rcia present:
12) The oa'cia, which do not issue from the boundary between two zooecia placed in the same longitudinal row, are covered by kenozooe- cia; (the proximal part of the zorecium separated from the distal by a more or less distinct constriction a little distally to the distal wall).
13) The ooecia are placed on zoa'cia of ordinary size; zoa'cia very asymmetrical, from the narrow tube-like proximal part widening into an obliquely funnel-shaped extremity, furnished with spines; as a rule there are found avicularia, the radical fibres, which go down along the l)asal surface of the colonj', issue from a rosette-plate a good way
distally on the basal aspect of the zo(L'cia Conmcopina n. g.
13) The ocecia are placed on zooecia of smaller size; zoa;cia sym- metrical or only a little asymmetrical; no sj)ines; no avicularia.
14) The basal edge of the distal wall angular; the oa'cia-bearlng zooecia placed between two zoa'cia in a bifurcation; (the frontal wall of the kenozooecium membranous, furnished proximally with two calcareous ]irocesses; (no rosette-plate between two neighbouring
zooecia Didijinia Husk.
14) the basal edge of the distal wall not angular; the oa>cia- bearing zooecia attached either j)roximally to the frontal area or to the basal surface of other zocecia; the frontal wall of the kenozoa>cium calcified Eucralea Lamouroux.
12) Free oa^cia issue from the boundary between two zooecia placed in the same longitudinal row:
15) The distal wall furnished with four uniporous rosette-plates, each of which is jjlaced at the bottom of a se])arate chamber; (no avicularia) Dimclopia Busk.
15) The distal wall not formed in this way:
16) Each zoa»cium has a strong muscle, which at its distal end is attached to the inner side of the external wall of the zoa'cium, and at the other to a conical ])rojecti()n from the distal wall of the next
99
lower zo(Pciuni; two successive zofccia separaled by a small iiiicalci- fied space; the distal wall has an uncalcified multiporoiis losette-plale; the radical fibres which arise from the hoiiiidary between two zo(L'cia at their rim, run proximally and join, filling the spaces between the branches in the proximal part of the funnel-shaped colony) .. . Kineloskids Koren-
Danielsen.
16) No such muscle; no uncilcified space between the zoa3cia:
17) Each zoircium consists of three sections separated by constric- tions, of which the middle one is elongated, cylindrical, while the distal one is obliquely funnel-shaped (avicularia freely movable; the basal edge of the distal wall unequally asymmetrically angular; the radical
fibres issue from the basal side of the zofrcium BicclUuin Hlainville (mod.).
17) The zooecia not divided into three segiuents separated by con- strictions:
18) The basal edge of the distal wall is angular:
19) Distal wall with two multiporous rosette-plates; sessile avicu- laria Biiyiilaria n. g.
19) Distal wall with small uniporous rosette-plates; free avicularia; (zooecia widening from a narrow cylindrical [)ro\imal [)arl into an obliquely funnel-shaped extremity; radical fibres issue from the lateral margins of the zoa^cia) Bicellarina n. g.
(B. Alderi Busk). 18) The basal edge of the distal wall not angular:
20) Distal wall very slightly ascending, with several uniporous rosette-plates; no avicularia; radical fibres issue everywhere from the covering membrane of the frontal surface in the two-layered colony . . Wdlcrsid n. g.
20) Distal wall consisting of a basal, horizontal part with a muili- porous rosette-plate, and a frontal strongly ascending part ; freely movable avicularia ; radical fibres issue from the second (more seldom also from the first) rosetle-i)lalc of the marginal zocecia DendrobcanUt n. g.
In the al)ove synopsis of the genera, in which the degree of relationship is not expressed by their consecutive order, 1 have not been able to take account of a series of earlier described forms, which I do not know from |)ersoual obser- vation. So far as Hnxleya is concerned, this genus is said to have a completely calcified, arclied frontal surface, and does no! seem to belong in any way to
100
this family. Brcllui liibcvformis seems according lo Hi neks' figure lo liave an angularlj' bent dislal wall and would therefore, according lo the above given synopsis, have to he referred to Genwllaria. Regarding Syniwtiini aviculure I have no information about the structure of the distal wall, and if this, as in Gemellaria loricdta. is angular, there might be some ground, in spite of the presence of avi- cularia, to refer il to the genus Gemellaria. A closer examination of those mem- bers of the family, which Busk has described in the Challenger Expedition's Bryozoa will no doubt lead to the setting up of several new genera, and Busk explains also that to avoid doing so he made his definition of the genus Biigiila very elastic, whilst at the same lime dividing the species into four groups.
It will for these species be of j)rincii)al interest to lind out whether they have an operculum or not, and also how their distal wall and ooecia are constructed, hi Biujiila iniiabilis and '•Biigiila<' leontodon, of which two species I have been able to examine a small fragment without ocrcia, there is an operculum as well as an angular distal wall, and these together with two other species are referred to Busk's first group, where the ooecia which only a])j)ear in the median row of the colony, are enclosed in the proximal part of the higher placed zocrcium. The question is therefore, whether these si)ecies form a new genus or whether they can be included under Diclymia, the ooecia of which however are surrounded by kenozoci'cia. In Biigiila bicornis the higher j)laced zorrcium arises far back on the basal side of the lower and meets with this in a circular disk. The form, which Busk mentions under the name of Diachoris nuHjellanica, v. distans. but which he has not made the subject of any description, seems, to judge from Ihe figure given, not only to be a separate species, but also to represent a new genus. The whole frontal wall seems namely to be calcified except for a median longi- tudinal slit, which proximally is much widened, and in front is continued right to the aperture, which is provided with a sinus.
Bugula Oken, char, emend.
The zo(vdiiiu without an operculum. Distal wail with a basal angular edge within which there is row of uniporous rosette-plates. Freely movable capitate avicularia; free (xvcia. The colonies free, branched, the zooecia in two or more rows.
Waters as is known has shown, that an operculum is wanting in Biujula, and Calvet has confirmed this observation lor Ihe French species. Whilst I am certain that an operculum is absent in Ihe other /J(/.(/H/«-species, which are found in our Zoological Museum, I am not (luile so sure of this for B. calicnlala, be-
ini
cause llu' individual zud'cia in Ihe badly prt'served colonies seem lo nie lo show a trace ol' an operculum, and if lliere is nol an even transition in this regard within the species we must very likely form a new genus for the species with an operculum. The angular bending of the distal wall may reach its maximum in li. (Ii'uldld Lamx, where the two lateral halves in some zorecia almost reach the proximal end (IM. V, figs. 1 a b).
Bugula caliculata n. sp. (PI. Ill, figs. 1 a-1 q.)
The zooecia, which from the narrow, proximal end increase in width distally, have on the outer distal angle a very short, curved spine, and on the inner a very long thread-like spine a little lower in position. In very j'oung and developing colonies however the first 3 — 7 zooecia have 2—3 long spines, and in such colonies the ancestrula is even provided with 6, of which the third (the lowest) on each side is placed at double the distance from the second as the latter from the first. The membranous portion of the frontal wall which in the ancestrula occuj)ies nearly half the length of the zoa>cium has in the common zooecia a much larger extent, hi the few single zooecia succeeding the ancestrula there is found a constriction in the proximal part (figs. 1 d, 1 e).
The avicularia occur only in a relatively small number, and are situated a lillle within the outer lateral margin and a little distally to the proximal end of the zooecium. Each zooecium of a pair, where the bifurcation commences, is in most cases furnished with an avicularium, a rule, however with not a few excep- tions, especially at the last bifurcations. Besides these, a number of avicularia occur apparently without any very definite position.
Ooecia small, globular, and their longitudinal axis is a continuation of that of the zooecia.
The stem is jointed and consists of a row of long, narrow segments (keno- zocecia) widened a little at both ends and rounded quadrangular in section. The distal end of such a kenozoa-cium is provided a little proximally to the joint constriction (fig. 1 1), with a distal wall, saddle-shaped from side to side and from the front to the base, which on each side is furnished with 4—5 small, uniporous rosette-plates, all of which may sometimes be separate, sometimes con- nected together in groups. This calcareous distal wall is continued internally along each of the two lateral surfaces of the kenozocecium as a calcareous band (fig. 1 (j) which as time goes on increases in width and in thickness. The two bands join together to a ring-shaped portion (ligs. 1 1-1 m) at the proximal part of the segment, and the intention with the whole of this arrangement is evidently
102
to strengthen the resisfiiig power of Ihe otherwise slighlly calcilieii stem. Along the middle of tlie frontal surface of each segment we find an exceedingly nar- row membranous frontal area, which even in its distal part is furnished with parietal muscles (figs. Im — In), which Kirkpalrick has also found in B. (Stirparia) Hnddoni. New colonies arise from the stems of the older, taking their origin between two contiguous segments, and the j'oungest, which have a very small number of zoa>cia, possess only a single stem-segment, which in time increases in lenglh and seems to be formed by a constriction of the j)roximal pari of Ihe anceslrnla (figs. 1 c, 1 d, 1 f). After the ancestrula follow two still solilaiy zooecia, after which Ihe first bifurcation commences. The older colonies, with from 3 — 17 joints, have only one solitary zoa'ciuni, which according to the age of the colony sometimes has altogether 2 — 3 spines, and sometimes none at all, while Ihe distal wall, as in Ihe segments is connected with two calcified bands whicli are fused together in Ihe jiroximal part of the zoa^cium into a ring. A larger or smaller number of the older zoo?cia according to their age show a similar Iransformation, and a comparison between the youngest and oldest colonies leaves no doubl about the fad, Ihal the solitary zooecia in Ihe proximal . portion of the colony are in time transformed to segments, while the proximal segment arises from a constriction of the proximal part of the ancestrula. I cannot determine with certainty how the other segments are formed, but as new colonies can arise between two segments, it seems reasonable to suppose, that new seg- ments can also be formed between two older ones, and the fad that the seg- ments may have a very dilTerent length favours this supj)osition. Neveitheless, I have nowhere found Ihem so short that I could consider them as just beginning.
The radical fibres, which in the older parts of the stems issue in numbers from uniporous rosette-plales in the areas between the two strong, calcified bands, are simple calcified fibres, which partly cover the trunks, partly project freely from these, hi some places they are pear-shaped, swollen in a part of their course and contain a strongly refractive, shining mass, while such swellings at other places project freely and thereby assume a great likeness to the gonothecae in Ihe Hydrozoa. As far as the physiological importance of these swellings is concerned, I would j)ut forward the supposition that they serve for the accumu- lation of reserve materials. Waters' has found (juile similar formations in liu- gnla (Stirpciriri) glabra Hincks.
The colonies are frequently compound, and Ihe small colonies have the form of stalked caliculate tufts, the branches of which show (5 bifurcations in the
' 111, p. 20, fig. 1.
103
largest ones. In the largest the stalk or stem has a length of ill mm., and tlie cup a height of 75 mm.
It is not quite clear to me whether the above-mentioned, (juite young colonies have arisen by budding from the older colonies, or whether they originate from larvaj which have attached themselves. The fact that they arise as a rule be- tween two segments, whilst a single one of them issues from the frontal surface of another zoaxiuni in a somewhat young colony, speaks in favour of the lirsl view. While the one stem-segment in the very young colonies is very thin and rather short, I have observed in various colonies, both in young and in somewhat older, a thick and long, newly formed segment with a distinct terminal growth, arising sometimes between two stem-segments, sometimes between a stem-segment and the ancestrula, or between the two oldest zoa'cia (fig. 1 g). In these cases the colony always seems to commence with the formation of a stem.
A number of colonies of this species were collected at Hongkong in shallow water by Captain Suenson.
I originally believed this species to be identical with Stirjxirict Huddoni Kirk- patrick\ and the figures of this species are therefore indicated by the latter name on Plate III. A closer comparison with Kirkpatrick's description and figures has however convinced me of the independency of the species here de- scribed. Si. Haddoni not only lias no avicularia or spines, but differs further from B. caliciilota in the strongly arched basal surface of the zocecia. and their strong turning inwards towards the middle-line of the branch. In both these features B. Haddoni shows a great resemblance to the new species B. candhica to be described later.
Bugula glabra (Hincks).
Slirparia glabra Hincks, Annals, nat. hist. 5. S. Vol. XI, pag. 196, PI. VI,
fig. 2.
Bicellaria glabra (Bicellaria stylites in tai)ula) Busk, Challenger, Zoology,
Vol. X,^*in>g- •^i'. !''■ VI, fig. 1 a. Stirparia glabra Waters, Journ. Linna;an Soc, Zoology, Vol. XXVI, pag. 19
(I'l. Ill, lig. .Sa).
I have examined a very young colony of this species with S stem-segments and only 3 full-grown zoircia, in which the ancestrula has only 3 long spines on each side, whilst a larger number (5—7) occur in the specimens examined
> 49, p. 603.
104
by Ilincks and Busk. The dislal wall is anf;ulaily l)eiil, and lo judgi' from the slrucliiiT of these zoa'cia this species can he rct'erred neither lo Hiccllnria nor lo Conmcopina. The sliiiclure of the oa»cia is not known. Tlic stem-segments have a structure cjuite similar to tliat of llie last sptcies, and the above-expressed suggestion, that new segments may be inserted lielween the older ones, is streng- thened by the fad that every second segment of the specimen examined by Hi neks is scarcely half the size of the others. There is also a very small seg- ment (the tifth) in the colony examined by me. According to Waters' investi- gations, the radical libres quite agree with those in li. cdlicuhiht and have especi- ally the same kind of pear-shajjed ex])ansions.
The small colony which I have received through the kindness of Miss Jelly, comes from Port Phillip, Australia.
Bugula caraibica n. s\^. (I'l. Ill, ligs. 2a-2n).
The zotecia, which increase in width distally from the nari-ow ])roximal end, are turned inwards towards the middle of the branch, in sucli a way, that the frontal areas of two neighliouring zoa'cia form nearly a right angle with one another, and they have thus, to judge from Kirkpa trick 's tigure, been subject to a much smaller turning than the zoa'cia in B. Hmliloni. The frontal end is cut off straight and the basal surface strongly arched with an almost semicircu- lar transverse section. Almost in the middle of the distal margin of the basal wall there is in numerous zoo-cia a rather strong s|)iiie (fig. 2b), which may grow longer than the zoo'ciuni, but is often very short. It seems to be (juite wanting however in other zooecia. Theie is very seldom a very short, external corner-spine. The distal wall is insymmetrically angular (fig. 2 d), and somewhat distally from this there is a ring-shaped constriction.
The avicularia, which occur in very small number, are placed outside the membranous frontal area in its proximal portion.
The ooecia. the outer layer of which is calcified, are nu)ie than half the length of the zooecia, elongated, strongly arched and marked with radiating striae. They are placed obliquely relatively to the zoa'cia, and turned so much outwards that they can be seen in the wdiole of their extent from the basal as- pect of the colony.
The segments (Kenozooecia) of the stem are, seen in transverse section, circu- lar or perhai)s slightly (juadrangularly rounded. Here also we find two calcified thickenings internally, arising from the distal wail and showing lines of growth. They meet in a ring at the j)roximal end of the segment, but otherwise they
105
(iilVer from the coii-es|)onding thickenings or bands in ]i. niliciihild in several ways. Tluis, their thinner middle portion passes evenly over into two thicker, rounded marginal portions (fig. 2 k), and further they are much broader, occu- pying more than half the periphery of the whole segment. They divide this into lour, unequally large areas, of which the largest lies on the basal surface of the colony and the narrowest on the frontal surface. This last area which does not seem to have any membranous jjortion at all or to be jirovided with parietal muscles is not rarely divided into two or more areas behind one another, as the two calcareous thickenings may be connected by one or several transverse bridges. The distal wall (figs. 2 1 — n, 2 j), which is saddle-shaped fiom side to side, is over its whole surface provided with extremely numerous, small uniporous rosette- plates, so that the whole di.stal wall migiit really be regarded as a large multi- porous rosette-plate. In its whole extent it is attached internally to the wall of the segment by ascending, often branched chitinous rods, which are apparent from the outside anil produce digitate and lobate figures.
The colony consists of a nunil)er of jointed stems which have two alternate rows of llahellate branches with lour to five bifurcations and up to 40 linear segments with biserial zooecia. Each of these branches is in connection with the stem through a multiporous rosette-plate, which is placed a little proximally to the end of a stem-segment (tigs. 2 n, 2 i, 2 j), and such a rosette-plate is only found on that side of the segment where a branch issues. I have only in a few cases found two successive branches arising from the same side but never two branches placed at the same height. From each stem again 2 — 5 new stems arise, in most cases just opposite a branch, more rarely alternately with these, and in a few cases I have found a new stem arising just proximally to a branch. New stems which are in connection with the main-stems through multiporous rosette-plates seem to arise in a doul)le way, partly by transformation of branches and partly independently. While the common branches are fixed by a zocecium, the proximal part of which is provided with two rings, I have seen a number of branches only ditferent from the others therein that 1 — 2 slender segments are interposed between the zoo-cium and the stem, and most likely these branches are about to be transformed into new stems. A great number, however, of the young stems, which issue fiom the main-stems and for instance those, which are seen in fig. 2 a, cannot well have arisen in this way, which in the first instance may be inferred from their being generally placed opposite the branches, as two branches are never [)laced at the same heiglh. In the next place these stems are characterized by their being provided with branches only at a very late period though there is a rather large ditlerence in that respect. Only in a single stem
106
with two segmenls I ha\e louinl ;i lilllu leriniiiiil bianch showing a double l)i- liiicatioii while a eoinmon hianeli on a niain-sleni as already said shows 4 — 5 bifurcations. In all the other young stems tlie tip is devoid of a branch, which no doubt has fallen of. While a terminal branch is a direct continuation of a stem and does not arise from a losetle-plate, the formation of a rosette-plate always precedes the formation of a branch, and even if all the lateral branches have dropped of, as is the case in many of the stems examined, their position and number is indicated by the respective rosette-plates. The examination of a number of stems shows that the first rosette-plate appears proximal ly to the partition-wall between the end-segment and the one next to it, and that the development of these formations goes steadily downwards. I shall here give a few instances showing the difference in the appearing of the rosette-plalcs.
|
a stem witli : 6 joints |
Tlie fifth segment with a beginning rosette-plate. |
|
7 — |
Rosette-plates on the six segments. |
|
9 — |
A Rosette-plate on the seventh segment. The partition wall between the eighth and the ninth segments is not wholly developed. |
|
11 — |
Rosetplates on the nintli and the tenth segments. |
|
13 — |
Rosetplates on the eleventh and the twelfth segments. |
The number of segments in the trunk gradually increases by division of the older segments, and when two short segments follow one another this is a sign that a division has taken place lately. The proximal segment of the two has then not yet got the lateral rosette-plate, and the proximal end of the distal seg- ment does not yet show the rounded swelling defined by a more or less distinct constriction, which is seen on the completed segment. A division like this is always introduced by the two strongly calcified lateral belts on each side sending ))rolongations towards one another, which at last join together to form a bridge.
The radical fibres, which issue from the proximal end of the stems serve exclusively to attach these to the surroundings. They are much branched, furnished with irregular expansions and swellings, and like the stem divided into sections (kenozooecia), which inlernally are separated by multipbrous rosclte-j)lates, l)ut externally have no distinct constrictions. We further find a muiliporous rosette-plate everywhere where a new branch arises from an older one. While the radical fibres have in Ihe beginning on arising from the stem a struc- ture similar to the latter their wall soon becomes evenly calcified over the whole of its surface.
107
- The colony examined consists of c. 20 zod-c-ia-ljearing main Irnnks, of which the longest have forty odd segments and a length of l(i.5 etm. The segments have a length of 3 — 5 mm.
Christiansted lagoon, St. Croix (Fishery hispector Mag. Chr. Lofting).
Dimorphozoum nov. gen.
The colony consists of two layers, the zoa-cia of which are of exceedingly diverse natnre. In the one layer (the Ctenoslome) they are quite uncalcitied and have no operculum, whilst in the other (the Cheilostome) they have an oper- culum and the structure general in the family. The last layer has besides the following characters: the distal wall consists of a basal horizontal portion with a multiporous rosette-plate, and of a frontal ascending portion; free oarui; freely movable, club-shaped aviciilariu.
D. nobile (Hi neks).
Flustra nobilis, Hincks, Annals nat. hist, fi Ser. Vol. 7, 1891, pag. 288, PI. 6, fig. 5.
Waters Journ. R. micros. Sj/c. 1896,
pag. 281, PI. 7, fig. 10—11. (1^1. IV, figs. 1 a^l f).
The Clieilosloinc latjer:
The zooecia are elongated hexagonal, and the frontal wall membranous in al- most its whole extent. The distal edge furnished with 4 spines, which may vary considerably in size, and of which the middle ones are the longest. When they are not very small, each one of them sends out a small, distally directed branch from its proximal half. There are as a rule 4—6 bifurcated spines on the distal half of each lateral edge, which also vary considerably in size. The inner branch is generally the longest, and may occasionally reach more than half-way over the frontal area, it may als,o however be (piite absent. The distal wall ends basally in a straight edge, and there is generally a more strongly calcified belt (fig. 1 d) both proximally and distally. It is provided with a very large, multi- porous rosette-plate (fig. 1 c) and such is also found in Ihe distal half of each lateral wall (fig. 1 b)'. On the basal wall of a great many zoa-cia there are 1—4
' When I give the number of rosette-plates (109, j). 281) in tlie distal lialf •.)! the lateral walls it is because in species with independent lateral walls it can easily be seen (p. 27) that the rosette-plates (or at any rate their main parl^ as a rule belong to the distal half of the lateral walls, the proximal part only possessing a corresponding number of openings, each surrounded by a pore-ring. In species with common lateral walls only the rosette-plates in the distal half of a lateral wall have their con- vexity turned inwards.
lO.S
niultiporous roselte-plales, which serve as conneclion with the zou-cia in the second hiycr, and are convex towards Ihese (fig. 1 c).
The avicularia wliich Hi neks wrongly gave as niemhranaceous do not seem to occur on all zoa'cia, hut are in most cases represented l)y two. ^^'e can occa- sionally find 4. They are not, as represented by Hi neks, attached to the basal surface of the lower zocx'cium, hut to the proximal end of the liigher. Each lateral edge namely sends out a narrow prolongation directed inwards, to which the avicularia are attached, and at the place of attachment of each avicularium we find a small uniporous rosette-plate. The avicularia are conical or club- shaped with a straightly cut frontal area, and the operculum, which is broadly chitinized in the margin, has in its proximal part a half-moon-sha|)ed lucida (fig. le).
The ooecia which up to the present have been overlooked, are free, without slrialion, provided with an uncalcilied ectoocecimn and very low. They are how- ever somewhat higher when seen from the basal surface.
The Ctenosloiite luycr consists of quite uncalcified, elongated liexagonal zotccia with a two-lipped aperture, and they are in all respects much like the zoa-cia in an Alcijonidiuni. I can give no information about the rosette-plates, as I have only examined dried colonies, and it was only after moistening these that the dried-uj) zoix'cia of this layer showed their real nature. I have twice received material of this species from Miss Jelly, once a large colony labelled South Africa, and an- other time a number of fragments together with small colonies of CJutju'rid copensis, labelled Port Elisabeth. All these specimens, of which the last were richly furnished with ooi'cia, were quite covered with the layer of uncalcilied zoo-cia, and as the basal surface of the other zoa'cial layer is at the same time richly furnished with rosette-plates, I have no doubt that the two layers really belong together; but it would be very desirable to make an examination of fresh material in order to determine this (juite unique dimorphism with cer- tainty.
The colonies are foliaceous with slightly lobate margin, attached by a dense mass of radical fibres, which in the Cheilostome layer arise from the margin of the zocrcia in their distal half.
Bugularia nov. gen.
The distal wall angular with two niultiporous rosette-plates; the oo'cia free; (whuliivia sessile, not peduiu-iilnte.
109
B. dissimilis (Busk).
Carbasea dissimilis Busk, Catalogue of Mariue Polyzoa, Pari 1. Clieiioslomata pag. 51, PI. 50, figs. 4 — 7.
— — Busk, CiuUlenger, Zoology, Vol. X, Pari I,
pag. -5fT. S's
Fluslra dissimilis Waters, Journ. R. Micros. See. 1896, pag. 282.
(PI. V, fig. 2 a— d).
The zooecia elongated, quadrangularly tongue-shaped, with as a rule a niucli narrower proximal half, of which a larger or smaller part is calcified. Three pairs of spines may occur, of which fre(iuently only a smaller number is devel- oped. In colonies without oa'cia only the first pair is generally present, but even tliese may be lacking or rudimentary in many zocecia. In colonies with ocecia, it is rather difUcult to find this pair of spines from the surface of the colony, as they are placed in a hollow on each side of the oa>cium. The marginal zorecia which are longer than the others, are drawn out into a plump corner- spine. The distal wall, which is furnished with two multiporous rosette-plates, is much bent angularly, and has besides a distinct saddle-s]iaj)ed curve from the front to the basal side (fig. 2 b, 2 c). Each lateral wall is furnished in its distal half with two multiporous, strongly projecting rosette-plates. The basal surface of the zooecia is coarsely striated transversely (fig. 2 b).
The avicularia which are placed in the middle of the proximal, calcified portion of the zowcia are attached by means of a rather wide proximal part and the tii)s are turned in diil'erent directions.
The ocecia are not as fiee as they are in Biujula, rather a large part of their basal wall being firmly connected which tlie higher zoa'cium. They are very large, furnished with an uncalcified ectooo'cium, and the endoooecium besides a distinct double striation also has a cliaracteristic system of lines bounding triangular or s([uare api)arently impressed meshes.
Cornucopina nov. gen. Bicellaria p. p.
(PI. IV, fif^s. 4 and 5).
The zixrcid widening from a long, tube-shaped proximal end obliipiely up- wards, funnel-shaped, with a ring-shaped constriction at a greater or less distance from the distal wall. The mrcift, which are not placed between two zocecia in the same longitudinal row but on the zoa-cial distal margin, which is directed outwards from the middle of the colony, are surrounded by kenozo(x'cia. In most
110
species appear nviciilaria, which are generally capitate and pedunculate or trumpet- shaped. The radical fibres, which run down along the basal side of the colony issue far distally on the individual zoa'cia. The colonies are elegant tufts with biserial branches.
This genus which will most probably be split up later into several includes the majority of the species in the old genus Bicellaria\ and the only species known to me which remains in this genus is B. ciliata. One of the characters which, in a narrower sense, separates the genus Bicellaria from Cornncojnna, is the sharp constriction between the wider funnel-shaped terminal portion of the zoa>cium and the proximal cylindrical portion, and Corniicopina yrandis in this structural feature approaches Bicellarid, as we lind at the same place internally a narrow, ring-shaped, oblique, chitinous thickening. This species also occupies a special position within the genus in having a cryptocyst (fig. 5 a), already ob- served by Harmer-, which extends under the larger part of the frontal mem- brane and reaches almost to the operculum. It is provided with hnely curved and dentated edges, and it rises dislally from the deeper, proximal part to end in a free, shovel-shaped plate. Two successive zooecia are connected by a multi- porous rosette-plate, which is surrounded l)y a calcareous ring, and this is again connected with a similar ring surrounding the adjacent rosette-plale of the lateral wall (fig. ii a — 5 b). Busk has overlooked the very large plump avicularia, which in this species here and there issue from the basal surface of the zooecia a little proximally to the outer margins (fig. 5 c).
Beania Johnston. Diachoris.
The very slightly calcified zon-cia are mutually connected by cylindrical lubes to a more or less open network, which is attached to the underlayer by radical fibres arising from the basal surface of the individual zocjecia; each lube is fiirii- ished with a multiporous rosette-plate; no oa-cia; as a rule freely movable avicalariu.
While all the species, which I have been able to examine of this genus, have an operculum, such according to Busk's^ account and figures, is lacking in Diachoris tmujclUtnicn, in which the aperture is said to be surrounded by a circu- lar thickened rim. If this account is correct, this sjjecies must jjrobably be re- garded as the re[)resentalive of a s])ecial genus, and this inii;lil tlu'ii retain the old iianie Diaclwris. — In the sj)ecies from Ita[)allo, which Waters calls />'.
' 8, p. 31. - 111, p. .cjii
Ill
nui(jelhuiic(i\ ami of which species this wriler has been so kind lo send nie a fragment, there is an operculum:
Hiantopora Mac Gill.', char, emend.
The strongly calcified zooccia are connected by cylindrical processes, each of which is provided with a multiporous rosette-plate. The oo'cia tree; sessile avi- cularia; the colony attached by radical fibres, which issue from the basal wall of the individual zorecia. From the proximal portion of the avicularium rises a hollow spine, which as a rule is strongly branched and may cover over a larger or smaller part of the frontal membrane.
H. radicifera (Hincks).
Membranipora radicifera, Hincks, Annals nat. hist. 5 S.
Vol. 8, 1881, pag. 5, PI. 2, figs. (J, 6 a, (i b.
(PI. IV, figs. 6 a— 6 c).
The zooecia are broad, hcxagonally rounded, with two short, blunt spines and a little further proximally on one, generally the left, lateral margin with a short l)ifurcated spine with two unequally long branches. The strongly arched basal surface runs out into six, a little lower placed, but also arched, .somewhat broad and short tubes which are separated by broad and deep pit-like depres- sions and meet with corresponding processes from the neighbouring zooecia. At the bottom of each pit is an oval hole, which opens on the frontal surface of the colony, but on account of the somewhat imbricate position of the zo(Bcia, these holes are not very distinct. They open on each side of the distal end of the zoiL'ciuni. Each tube is furnished with a large, multiporous, strongly calcified rosette-plate, occupying the whole of its breadth, and the arched basal surface of each zod'cium is furnished with 4 6 uniporoiis rosetle-])lates, which serve for connection with the numerous radical fibres, by the aid of which the colony is attached to its underlayer.
The avicularia are large, proximally furnished with a small, curved spine, and provided with a mandible, which is inclined to one side. Each zoa'cium has such an avicularium attached along the one lateral margin and directed oblicjuely inwards, opposite the above-mentioned bifurcated spine.
The ooecia, which Hincks does not mention, are free, widest at the proxi- mal end, cup-shaped or semi-conical, furnished with an obliquely ascending
in. p. iCi, - 7.'). p. .a^ 7(i. pp. (id— (ii. •208
112
frontal surface, and with a calcified, rugged ectoooecium. On each side of the oa'ciuin is a small ohli([uely placed si)ine.
1 have been able to examine a colony ol' Ibis species from Port Phillip, Vic- toria (Miss Jelly).
To the genus Hinniopora, which Mac Gillivi-ay lias founded on "CrihrUhui' fero.v, I must, besides Ibis sj)ccies, also refer Mcnibvdnipord rddicifent as well as the form which Kirk])a trick has described under Ibe name M. nuiicifcra, v. intermedia, and which he considers as an intermediate form between //. /c/o.r and H. radicifera. I agree willi Ibis writer as to tiie necessily of referring all three forms to the same genus; bul whilst he refers them to Meinbranijmrd, I must, partly on account of their points of agreement with lieania, partly because of the free ott'cia, refer them to the family liicellariidae, and although they must come close to Beanid, they camiot for several leasons be included under this genus. Some of these reasons are: the strong calcification, llu- |)resence of oa-cia, wbicb however have hitherto only been found in H. radicifera, and finally the ])resence of the sessile avicularia (in conlrasl to the pedicellate inovai)le ones in Ileania). Lastly this avicularium is in all three species furnished with a spine, wliich in each attains an extremely variable development, and in //. fero.v coxers (be greater part of the frontal surface with its branches, and Ibis is the reason why this species was formerly referred to the genus Cribrilina. In //. radicifera it is rallier small undivided, conical, whilst it is much larger and richly branched in //. intermedia, but in contrast to the spine in //. ferax it projects fieely bere. Of H. ferox besides Kirkpalrick's original specimens I have been able to examine two others, namely one from Port Phillip (Miss Jelly) and another from Port Phillip Heads (Mr. J. Gabriel); they show all dilferences in tbe shape and development of the aviculaiian s])ine, so that the species seems to undergo great variation. It may be possible to set up several dilferent species. All three species agree however in that tbis hollow aviculaiian spine wbicb may in realilv be looked upon as a hollow, branched continuation of tbe avicularian cband)er, is not, as Kirkpatrick seems to believe, connected with the opposite margin of the respective zocKcinm, but nuiinly witli parts of the surrounding zott'cia, |)ailly with their distal spine or distal margin, |)arlly with their avicularia or with the branched prolongations of these. The tip of the avicularian .spine is however often fused togelbei- witb a small branched spine, which ari.ses from the distal half of tbe opposite margin of tbe zoo'cium.
Mac (iillivray', who originally i-el'erred tbe genus liiaiihiiinrii to IJic I'amilv
' 75, i).,4«r
rot
113
Cribrilinidae, has in a later paper' made this genus into a special family Hianlo- poridae, to which he also, besides some fossile forms, which I Iiave not had the opportunity to examine, refers Cribrilinn monoceros, and Hincks'-' stated already in an earlier work that the two species ought to be united into one genus, and that this genus ought to represent a new family. I cannot admit, however, that there is any relation between the two species which only show the external agreement, that a larger or smaller part of their frontal membrane is covered by branched projections; but whilst these are hollow and originate from the avicularia in //. ferox, they are solid and originate from the lateral margins in C. monoceros.
They thus show a difference in the only structural feature, which could be in favour of their being united to form one genus. As the genus Hiantopora, accor- ding to the foregoing definition naturally belongs to the familly liicelhiriidae, I am unable to adopt Mac Gillivray's family.
Brettia Dyster.
? Maplestonia, Mac Gillivray.
(PI. IV, figs. 9a-01}).
The distal wall is not angular; o(vcia and avicularia wanting; the colony with single-rowed zoa-cia.
I must for the present refer Maplestonia to this genus, as there is nowhere in the diagnosis given by Mac Gillivray a character sufficient to separate it from Brettia. I have been able to examine a small fragment of a colony of M. simplex with some few zociecia, the frontal membrane of which is surrounded by a more strongly calcified cryptocyst with fine lines of growth, which also surrounds the distal wall. Otherwise the two species M. cirrata and M. simplex seem to show great differences, and the first' resembles Catenarin in its whole mode of growth.
The form, which Waters^ has named llrellia friijida and of which he has been so kind to spare me a little branch, is, as he has himself supposed, identi- cal with Smitt's liiigula qvadrideiitata, wliich is only a growth-form or variety of Dendrobeania Miirraijnna. This species sometimes appears with mulliserial (4 — 26 rows), sometimes only with uni- to fourserial branches (H. qvadridentata) and of the last form I have through the kindness of Prosessor Theel, Stockholm been able to examine colonies from Spitzbergcn. In contrast to the species of the genus Bmjnla as defined here, the distal wall in I). Miirraijana is furnished with a multiporous rosette-plate, and in the distal part of each lateral wall, we find two
' 7G, pp. GO— Gl - :!8a, p. 479. = G7, p. 92. * 114, p. jl.
114
such plates, placed close together on a more strongly calcified and proxlnially sharply defined part of the zoa^ciuni. The same is the case in Brettia fri(jida, and I shall only mention further, that whilst the zooecia in the uniserial hranches are as regards rosette-plates provided in (juite the same way as the zooecia in the many-rowed hranches, they lack the holes on Ihc other hand in the proximal portion of the lateral wall, which in the zoa?cia with several rows, correspond with the rosette-plates on the neighbouring zooecia.
Petalostegus nov. gen. Catenaria p. p.
The membranous frontal area is covered by a circle of mulually connected plate-like or leaf-like hollow spines; a slightly chitinous, semicircular, simple operculum; sessile avicularia; free (?) ooecia; zooecia in one row.
P. bicornis Busk.
Catenaria bicornis Husk, Challenger, Zoologj', Vol. X, PI. 1, pag. 14, PI. 2,
figs. 2 a, 2 b.
— — Waters, Challenger, Zoology, Vol. XXXI^, p. 9, PI. 1, fig. 1.
(PI. IX, figs. 8 a, 8 b).
The zooecia widened upwards from a long, narrow, tube-shaped proximal part, oblique quadrangularly oval, strongly arched especially on the frontal sur- face, the largest part of which is formed by a membranous area, covered by five mutually coalesced hollow spines. These, which spring from the rim of the frontal area with a relatively narrow proximal part, have a broad rhombic form and are therefore in the marginal part of the frontal area separated by four wide, but low interspaces, which are bounded externally by the edge of the frontal area, internally by the proximal edges of the rhombic spines. At the two distal spines the corresponding space is formed by the aperture itself. The distal much longer portions of the spines are each furnished with 2 — 3 very short projections, which meet wilh corresponding projections from the adjacent spines, and the five radial sutures are thus j)rovided with 2 — 3 larger or smaller oval pores. Of the five spines the proximal is the largest, and meets with the two distal in a triradiale suture, whilst the two others which are the smallest do not reach in lo the middle of the area. The rhombic form of the three larger spines thus becomes somewhat modified, in such a way that the proximal s])iiie is strictly irregularly hexagonal, and the two u])per pentagonal. The aperture, which is placed a little proximally to the distal edge of the zocecium, is almost semi-
115
circular, though in such a way that its distal curved edge (the anter) meets with the almost straight proximal edge in two almost parallel lateral margins. The aperture is occupied by a membranous opercular valve with a chitinous rim. On the basal surface in the distal part of the zooecium between the two avicularia we find a small, more calcified, quadrilateral area.
The avicularia which are placed on each side of the distal part of the zooe- cium, are somewhat strongly compressed with an elongated oval frontal surface which is tuined outwards. Seen from the side they are trapez-shaped with a small hook-shaped curve.
The ooecia are lacking on the branches examined by me, but according to the description (»galeriform, lofty, terminal*) Busk gives, there is hardly any doubt that they are free.
The colonies have uniserial branches, and from each zocecium issue two new ones, one from the tip, and one from a triangular projection on one (the right and the left in turns) of the lateral walls, a little above the centre of the wider terminal part of the zoojcium.
I have been able to examine a small branch of this species from the Chal- lenger's station 280, which has been kindly placed at my disposal by Mr. Kirk- pa trick from the British Museum. In favour of its reference to this family speak not only the agreements in mode of growth and zooecial form with Bretlia, but in still higher degree the free ooecia, since free ooecia do not appear in any other Malacostege family.
Chaperia Jullien ^
The distal part of the zocpciiiiu is furnished internally with two lateral spaces open towards the frontal surface (sometimes coalesced to a single horse-shoe- shaped one), formed by two plates which project from the side-walls and converge towards the distal wall. Each distal wall has 2 multiporous rosette-plates and the distal half of each side-wall a single one. Hyperstomial free oacia with a com- pletely calcified ectooa'cium. The zod'cia which may sometimes have a membranous opercular valve, sometimes a chitinous comj)ound operculum, are generally strongh' provided with spines and have often a well developed cryptocyst. Avicularia sometimes trumpet-shaped, not always present. The colonies are incrusting.
To this genus belong the following species: Ch. annulus Manz (^ Ch. (juleata Busk), Ch. cristatn Busk, Ch. ceruicornis Busk, Ch. cijUndracea Busk, Ch. albispina M. Gill.', Ch. capeims Busk, Ch. patiilosa Waters', Ch. tropica Waters^ etc.
' 45, p. Gl. ' (14, p. 116, pi. fig 10. ■' 11,'), p. :!3. * 110 a, p. 168.
116
Family Farciminariidae Busk.
(PL I, ligs. in-in).
The zoa'cia as a rule slightly calcified, occasionally with a small secondary cryptocyst, without true spines, furnished with an ohliipu-ly asceiuiing distal wall, and separated by common lateral walls which are furnished with a small number (2 — 4) of uniporous rosette-plates. The aviciilaria dei)endent, sometimes depressed, sometimes strongly projecting. The o<vcia are endozooecial, generally more or less projecting, occasionally surrounded by kenozoa'cia.
The colonies are, in the hitherto known forms, dichotomously branched tufts, with slender, prismatic, sometimes jointed segments, on which the zonccia are arranged in longitudinal rows (generally 4 — 6) round an axis, formed by the adjoining separating-walls.
This family agrees with the Fhistridw in the possession of endozooecial otrcia, and with most members of that family in its being furnished with unii)orous rosette- plates. On the other hand it differs from the Fhistridcv in possessing dependent avicularia, in the lack of hollow spines, in the absence of independent lateral walls as also in the form of colony.
Columnaria nov. gen. Farciminaria, Busk p. p.
The zooecia are without spinous processes; the distal wall has a number of scattered nniporous rosette-plates. The oo'cia are strongly prominent and the cndoorrciuni on each side partially covered bj' a little lamina of cryptocyst, which issues from the respective lateral wall of the zooecium. Capitate (wiciilaria, attached to the distal wall at their proximal part and firmly fixed wilii Ihcir basal wall to the frontal membrane of the distal zoa'cium; the fiontal wall of the avicularia without a calcareous transverse bar; the colony not jointed.
C. borealis n. sp.
(I'l. I, ligs. 12:i-]2c).
The zooecia, the whole frontal surface of which is membranous without a cryptocyst, have an elongated rectangular shape; the length is generally 4 — 4.5 times the breadth. The strongly ascending distal wall which is only half as broad as the frontal area, is elongated pentagonal, or rounded wedge-shaped and furnis- hed with 5 — 9 rosette-plates placed in 2 longitudinal rows. The side-walls, whose distal half is furnished with 2 uniporous rosette-plates, increase in height towards the distal end and terminate in a triangularly rounded, projecting corner.
The avicularia, which appear in all zocecia are attached to the distal end of
117
Ihe distal wall by their proximal, sometimes almost tap-like, proximal end, and hy means of a unij)orons rosette-plate are connected with the proximal zod'cium, whilst their more arched basal surface is grown together with the frontal mem- brane of the distal zowcium. Seen from the frontal surface the\' are egg-shaped, seen from the side triangularly rounded, and their subopercuiar portion, which is turned in towards the distal zoa-cium, forms an obtuse angle with the semi- circular, outwards facing mandible which has a chitinous margin, but no > lucida' .
The ooecia are large, broad, flatly arched, rugged, and furnished with a pro- truding proximal rim, which is separated from the other part by a ring-shaped impression. From each of the distal zowcium's calcified lateral margins issues a narrow, obliquely triangular calcareous plate, which pushes in between the endo- oa'cium and the ectooa-cium, and comes to lie over the former with its concave lower surface. It is furnished w'ith a shorter inner, and a longer outer, free marginal edge.
The colony is bifurcated u]i to three times and the zofx-cia arranged in four longitudinal rows.
A single colony of this species was taken by the Ingolf Expedition at hit. 600 17/ N jQ„g^ 540 05/ y^r at a depth of 1715 fathoms.
All the Farciminaria species which Busk has described in the Challenger Report except F. atlantiai undoubtedly belong to this genus.
Farciminaria Busk p. p.
The zou'cid have a larger or smaller number of small, spine-like processes, which are placed either on the frontal membrane or on the lateral margins; the (Hx'cid are surrounded by kenozoa'cia; an (tinciilariiiin similar to that found in Coliimnaria occurs in a few cases; the colony not jointed.
F. uncinata Hincks. Annals Nat. Hist. ser. 5, Vol. XIV, 1884, pag. 277, PI. VIII, Og. 2.
(I'l. I, lij<s. 10 a— 10(1). The zooecia, the whole frontal surface of which is membranous, evenly in- crease in breadth towards the broadedly rounded distal end, which is sometimes furnished with two short spine-like processes. The. frontal surface a little proxi- mally to the operculum has on either side a denticle similar to these, and a similar denticle, which varies somewhat in size and is sometimes double, arises from each lateral margin a little distally to the proximal end of the zooecium. It points in towards the middle line of the zocvcium, and seems to be placed under the frontal membrane. The triangular distal wall has within its basal rim
118
a small number (about 6) of uniporous rosette-plates, and the distal half of each side-wall is furnished with a single one.
No avicularia.
The ooecia are large, strongly prominent, flatly arched, roughly radiately striated on the frontal surface, with a varying number of large, cylindrical, club- shaped, knotformed or pointed processes. Hi neks' statement on the oa-cia: ^surface smooth, divided into distinct areas by raised partitions<, must refer to these projections, which reach right out to the covering membrane of the ooecium. The ooecia are borne by zooecia, which are furnished with a large operculum and with two proximal spinous processes facing inwards, but they lack the denticles, which otherwise occur on the frontal membrane. They are covered by kenozooccia, which have no denticles, but are furnished with a narrow calcareous border just like the ordinary zooecia, although this here does not reach right back proximally (fig. 10 b). The boundary between the kenozooecium and the ooecium-bearing zooecium, is formed by a distal wall, strongly bent at an angle, which has a transverse belt of scattered uniporous rosette-plates (10 d dw.), and which is furnished with a thickened, strongly calcified distal margin. If we cut away the frontal wall of an ooecium (fig. 10 e) we find outermost the narrow cavity of the kenozooecium, within this the ooecium, and proximally to this the thickened margin of the distal wall, behind which we can detect a number of rosette-plates. The keno- zooecium is separated from the higher zooecium by a distal wall of the ordinary structure (fig. 10 d).
The colonies form dense, very often bifurcated tufts, the branches of which have four rows of zowcia.
Some colonies of this species from Port Phillip Heads, Victoria have been kindly sent me by Miss Jelly.
F. aculeata Busk.
Catalogue of Marine Polyzoa, Cheilostomata,
pag. 33, PI. 44, figs. 4, 5, PI. 45 (bis.) fig. 6.
The zooecia hexagonally rectangular, a little within each lateral edge furnished with a longitudinal row of 4 — 5, very often bifurcated, upwards bent, chitinous denticles, and the distal margin of the zooecium is as a rule furnished with 2 — 4 similar, but smaller spine-like processes. The separating wails are as in the prece^ding species.
No avicularia.
The ocecia have a similar shape and structure as in F. nnciiuitd, but lack the numerous and strong processes, found in that species. On the other hand,
119
the covering membrane, which belongs to the kenozooecium, is fnrnished with numerous, pointed, scattered chitinous denticles, which thus corresjjond with those, found on the other zoa>cia. The distal wall between the ooecium-hearing zooe- cium and the kenozooecium is, as in F. unciiuita, much bent at an angle and I'urnished with a thickened margin. The kenozooecium has no operculum as it has been figured by Busk.
The colony has a similar structure as in the foregoing species, but the zooe- cia are arranged in 6 longitudinal rows. A colony from Port Phillip Heads, Victoria (Miss Jelly).
According to information kindly sent me by Mr. K. Kirk])atrick I must also refer F. atlaiilica Busk' to this genus.
Nellia Busk. Farcimia, Pourtales.
The zod'cUi without spinous processes; the distal wall has at its inner corner a single rosette-plate; the ooecla are in almost their whole extent immersed into the proximal i)arl of the ordinary zoa'cium, and project only very little on the surface of this; the avicularia are attached by a wide base or partially immer- sed, with calcareous transverse bar; the colony jointed.
N. appendiculata Hincks.
Annals Nat. Hist. ser. 5, vol. XI, 1883, pag. 199, PI. VII, fig. 4.
(PI. I, figs. 11 a- 111)).
The zocecia wide, rounded rhombic, with a memlManous frontal area which occupies almost the three-fourths of their length, and which, except for the pro- jecting distal edge, is furnished with an immersed cryplocyst in the remaining marginal part. Each distal wall is furnished with one, and the distal half of each lateral wall with a single uniporous rosette-plate.
The avicularia which occur in pairs for each zooecium are elongated, some- what curved, tapering towards the proximal end and furnished with an arched outer surface. They are placed in such a way that with their inner lateral edge they border on the distal half of a lower zooecium and with their outer lateral edge on the proximal half of a higher zorecium in a neighboining row. At the distal end there is an elongated frontal area perpendicular to the longitudinal axis of the avicularian chamber. The triangular mandible, which is directed obli- quely outwards and proximally and which is furnished with a Uuida, has like
' 8, p. 49.
120
the corresponding part of the avicularium a little hook. In a large number of avicularia the membranous covering of the frontal area is transformed into an acuminated tenfaculiforni process and in such avicularia there is no trans- verse bar.
The ooecia are almost semiglobular, but in the greater part of their extent immersed and only projecting externally as a slightly i)rominent pent-roof-shaped portion distally to the zoa^cium, which portion is at the sides bordered by the avicularia. This projecting portion consists of two calcareous layers, the ectozooe- cium being also calcareous.
The colony consists of somewhat short, cylindrical club-shaped segments with four rows of zocecia and 3 — 4 zod'cia in each low.
Port Phillip (British Museum).
N. tenella Lanik.
Nellia oculata Busk, Catalogue Marine Polyzoa, Cheilostomata, pag. 18, PI. LXIV, tig. (5, PI. LXV (bis), fig. 4.
(I'l. I, figs. 13 a— 13 c).
The zooecia elongated, quadrangularly rounded, with a proximal, calcareous portion, which may occasionally reach nearly one-fourth of the whole length of the zoa^cium. The elongated, oval frontal area is surrounded by a thin projecting rim, and at its posterior marginal portion there is a small .secondary cryptocyst. The distal part of the frontal area, which includes the operculum, is on each side separated from the remaining part by a small tooth-shaped projection of the lateral margin (fig. 13 c). The distal wall and the distal half of each lateral wall is furnished with a single uniporous rosette-plate.
The avicularia which appear in pairs on the proximal, calcareous part of the zooecium, are rather small, and have a large part of their chamber immersed in the colony, which part is apparent, funnel-like, through the lateral walls of the zooecium (fig. 13 b). At their proximal part Ihey are provided with a small pit for the insertion of the radical fibre (lig. 13 e), and al their distal part some- times with an oval, .sometimes a pear-shaped frontal area. The mandible which has a similar, variable form and is furnished with a small, beak-like hook is turned away from the zoo'cium.
The ooecia are immersed for the larger part of their extent and can only be seen from the outside as short, pent-roof-shaped projections (fig. 13d), which on each side are separated from the lateral walls of the lower zooecia by a curved suture (fig. 13 c). This projecting portion consists of two calcareous layers, as the ectooceciuin is
121
also calcareous; but it often however shows a narrow, uncalcified transversely placed area (fig. 13 c).
The colonies consist of four-rowed segments, and the individual rows may contain 4 — 12 zooecia.
The species is represented in our Zoological Museum from the Bass' Straits, Port Denison, Queensland, Texas, ^^'est-hulies (St. Thomas), Ceylon and Siani, and colonies from dilTerent places show differences, partly in the size, position and shape of the avicuiaria, partly in the more or less strongly ascending distal wall, and in the nuni])er of zoa>cia in the individual rows.
N. (?) simplex Busk.
Catalogue Marine Polyzoa, Cheilostomata, p. 19, PI. LXV, fig. 1;
PI. LXV (bis), fig. 3.
(PI. XXII, fig. 6 a).
The zooecia are elongated, narrow, tongue-shaped or roundedly rectangular, surrounded by projecting edges, wliich in their proximal half are sometimes slightly sinuated. Within each lateral wall in the whole of its length there is a low longitudinal ridge, and from this issues a cryptocyst, whicli especially distally is rather deeply immersed and attains more than half the length of the zocrcium. The aperture of the latter is almost half the breadth of the zoa^cium. The distal wall is in its innermost corner furnished with a multiporous rosette-plate, while the distal half of each side-wall has a single uniporous plate.
No avicuiaria or ooecia.
The colonies have ipiadrilateral branches with 7 to 16 zoa^cia in each row.
The Formosa-Channel, 35 fathoms, Suensson, lat. 32" 22' N., long. 128" 42' E., 170 fathoms (Suensson).
Kirlipatrick has referred fragments of a colony from Mauritius to this species, and the British Museum through that author has kindly permitted me to examine tlie preserved and mounted small branches, on wiiich the account of Kirkpa trick is based. As I have not been able to examine this form completely, however, I can only say here, that the outer resemblance is suflicienlly great to justify considering this form as a variety of N. simplex. The cryptocyst however is far less develoi)ed. The proximally slightly projecting ooecia are in the largest l)art of their surface only covered by the frontal membrane of the distal zooecium (the ectoooecium), but a little proximally to their distal end also by a crypto- cyst-bridge, which connects the two lateral margins of the zooecium and is lowest in the middle, and which in K irkpat rick's figure is seen as a low, and not
122
very distinctly marked transverse Ix-ll almost midway across the frontal surface of the oa>cium. The jiart of the ooecium lying proximally to this is furnished along the middle with a narrow ridge. This cryptocyst-hridge must undoul)tedly have arisen from a fusion of two triangular lamina> like those we have described in Coluinnaria borealis.
Family Flustridae.
The zoa'cia slightly calcified, with an aperture whicii occupies Ihe whole frontal surface, or at any rate its largest pari. Occasionally there is found a secondary cryptocj'st. The distal wall is always provided with a varying number (1 — 13) of small, uniporous rosette-plales, and such also appear as a rule on the side walls, which only in a few cases are furnished with mulliporous rosette- plates. Vicarious or independent avicularia. The owcia are endozocccial and immer- sed, generally in ordinary zooecia, occasionally in avicularia or kenozooecia. The colonies are in a few cases incrusting, in most cases free frondose, more or less richly branched, and with the fiee margin consisting of kenozoa^cia.
As the family is defined here, the main weight is laid on the possession of immersed orecia and vicarious avicularia, as well as on the slight calcification and the large frontal aperture, and I have therefore also referred ^Meinbranipora' fltistroides Hincks and M. serrata M. Gill, to this family: the latter species has been considered by Waters also as a Fliislnt. In conformily lo the above defini- tion of this family, I have been obliged to separate out a number of species, which partly have external ooecia, partly dependent avicularia. »F/Hs/r«« militaris, ^Fl." irassd, F/.o dissimilis and »F/. < nobilis are Ihus referred to the /JiVe//ar/iV/oc and ^Fl.'^ armata lo the Scnipocellariidae. Since however the ooecia and avicularia are lacking in a number of species of this family as in most other families, and as a number of Memhranipora species can have vicarious avicularia as well as a quite uncalcified frontal wall, it is difficult to draw a sharp line between this and the family Menihraniporidae. Memhranipora serrulata Busk is a species which has been regarded both as belonging to Memhranipora and to Fhistra. According loBusk"s original description it possesses immersed oct'cia, and if this were cor- rect, il would have to be regarded as a Fhistra. but I have not succeeded in finding ooecia in any of the specimens of this species, which our Museum has from the Fvara Sea or from Greenland, nor are they found on Husk's original specimens in the Brilish Museum. The species appears incrusting as well as in free, bilaniinate growths, but it differs from the Fhistra species, known to meg'in having mulliporous rosette-plates on the distal wall, as well as fully developed marginal zooecia, and I therefore find it more natural lo look upon it as a Mem-
123
branipora. Whilst the side-walls in the majority of the Fliislridae have uniporous rosette-plates, we find multiporous ones in the three species Fl. foliacea, Fl. car- basea and Fl. abijssicola, and it might be considered as part of the evidence for the systematic importance of the rosette-plates, that none of these three species have the cap- or cup-shaped ooecia, which are common in the family. Only in Fl. foliacea (PI. I, figs. 8 a— 8 b) we can find ooecia of a very peculiar egg-shape, which must have arisen in this way, that the distal wall has simultaneously formed an upper as well as a lower cap- or cup-shaped expansion. The peculiar apparatus for the ejection of the larvae, which Jul lien has shown in Fl. abyssi- cola, also seems to suggest a very distant relationship to the other Fliiatridae, but for the rest, we shall not here enter further into these questions. In many cases the proximal portion of the ooecia is covered by a low cryptocyst-belt (PI. I, figs. 2 b, 3 a, 6 a, 7 c), which originally arises out of two lateral halves which finally fuse together. It increases in height with age and may in time in Fl. fliistroides (PI. I, fig. 4 a) completely cover the oa?cium. On the other hand, there is in Fl. seciirifroiis a pair of fiat, oblicpiely placed cryptocyst-processes distally to the zooecial operculum (PI. I, figs. 5 a— 5 b, d. w.). In all the species, which occur in free colonies, their margin is formed by kenozooecia ,which for the rest can appear in very difi'erent ways; sometimes (Fl. foliacea, Fl. membranaceo- triincata, Fl. securifrons) as chambers of a similar form and structure as the other zocecia, but without an operculum, sometimes (Fl. biseriata, Fl. cribriformis) as narrow, tube-shaped marginal ridges, which here and there show internal sepa- rating walls. While such modified marginal individuals appear at several places within the division Ascopiiora, for instance in Onchoporella bombycina and Micro- porella flabellaris, I have not been able to find them in any members of the families Bicellariidae or Scriipocellariidae, and their presence or absence seems thus in doubtful cases to be available as a distinguishing character for these families. I must thus emphasize the fact, thai I have not been able to find such marginal zoa'cia in any of the above-mentioned species which up to the present have been incorrectly referred to the Fliislridae, and that their appearance has nothing to do with the number of rows of zoa^cia in the colony, is evident from the fact, that on the one hand they are lacking in the species mentioned, but on the other hand appear in Fl. bi.seriata, the true zocecia of which are two-rowed.
Jullien has made a beginning with the splitting up of the old Fhistra genus by founding the genus Sarsifhistra, and I will here propose the setting up of 4 other genera (or subgenera?), of which one must keep the name Fltistra, as it will contain the species Fl. foliacea, on which the genus was originally based. As we thus have no name for the rest of the species, which not yet have been
124
separated into genera and which accordingly must provisionally be characterized mainly in a negative way, I shall pro[)ose for these the name Heterofluslva, and the introduction of such a provisional name seems to me necessary in ail simi- lar cases.
Synopsis of the genera.
1) The side-walls with multiporous rosette-plates; if orecia are pre- sent, they are egg-shaped, the distal wall forming at the same time a distal and a proximal cup-shaped arch;
2) the larv?e are ejected through a chitinous tube, which opens distally to the zooccial operculum, and may be covered by a movable, calcareous valve; avicularia of the same size as the zorecia, lyriform;
the operculum with two large wing-shaped lateral expansions. . . Sarsifliisird .lull.' '^^'"^''''^ (S. abyssicola Sars).
2) No such apparatus for the ejection of the larvae; egg-sha])ed ocEcia may occur and smaller avicularia, the operculum of which has
no lateral expansions Fhistra (L.) Lev.
(Fl. foliacea, L. - carbasea, Ellis and Sol.) 1) The side-walls have uni[)orous rosette-plates; if ocrcia are pre- sent, they are cup- or cap-shaped, the distal-wall only forming a single arch :
3) The oojcia immersed into the bottom of kenozooecia (no avicularia,
colony with two-rowed branches) Kenella n. g.
(K. biseriala Husk.)
3) The oa?cia immersed in ordinary zooecia or in avicularia (the colonies with several rows).
4) The distal wall, at any rate in the onecia-bearing zoa'cia, very often also in the ordinary zocecia, meets with the basal wall in an angularly bent or curved line; the free edge of the onecia on the frontal side of the colony lies much lower than the basal edge; the avicularia have the same size as the zooecia, (the colonies much branched dichoto- mously, with frequcntlj' the branches meeting and thus forming an open network; radical fibres occur in the angles of the branches).... Relifliistra n. g.
4) The distal wall horizontal or very slightly curved; the free,
' 4(i, p. 4;i
125
frontal edge of the onccia is almost at the same height as the basal; the avicularia smaller than the zooecia:
5) The lateral walls within the covering membrane generally with numerous spine-like processes; the margins of the zooecium have as a rule more or fewer (occasionally numerous) spines; the avicularia generally with a pointed mandible; the oircia not rarely immersed in
the avicularia Spiralaria Busk.
(Hincksina Norm.)
5) The lateral walls never have spine-like processes, at most a single pair of spines: the mandible of the avicularia rounded, ooecia never immersed in avicularia Heterofhistra nov. nom.
Spiralaria Busk, char, emend.
? Hincksina Norman \
(I'l. I, fig. 9 a).
The lateral walls with as a rule a row of spine-like processes (or denticles) a short distance within the covering membrane; the edges of the aperture as a rule furnished with spines, sometimes over their whole length; the avicularia generally with beak-shaped, pointed mandible; the owcia most often immersed in avicularia; the side-walls have numerous uniporous rosette-plates.
As will be seen from the above diagnosis, the characters on which the genus is l)ased are not constant; but as these characters in the species which I refer to this genus supplement one another in such a way, that there can be little doubt that these species are closely connected, I must consider this genus as well-established, though its limits are not sharp. Besides in the species, which Busk originally described as Spiralaria florea-, the above-mentioned, spine-like processes on the side-walls are also found in Fl. denti(jera^, Fl. Hpii}iili[icra^, Fl. dentictilata^, to the last of which Busk has referred two fairly distinct forms, and it seems on the whole to, be subject to considerable variation. I may men- tion here the most important characters for the three forms in our Zoological Museum, which can be referred to .S. deiiticnlala.
A form from the Challenger St. 163 (var. inermis). There are no spine-like processes in a larger or smaller distal portion of the zoa'ciiiin, whilst in the proximal portion 1 — 11 appear on each side; no spines; typical (ivicularia, no (Hvcia.
A form from Bass' Straits. Strong, spine-like processes in almost the whole
' S.'i, p. .^S.'). ' (i, p. If)!!. ■' lOi).
126
length of the zoa'ciiim (up to 18 on each side), one or two pairs of spines on the distal part of the zooecium, typical ainciikiria, the oa'cia immersed in the avicularia.
A form from Victoria. The spine-like processes are much reduced and cannot be seen from the surface of the colony, appearing merely as small knobs. They seem also sometimes to be in very small numbers. Broad, flat, pointed spines appear in the whole length of the zowcitiin. Typical avicularia, the 0(ecia immersed in the avicularia. The form which Busk' described in 1852 differs from the last mentioned in that the teeth are well-developed and the spines partially widened at the tip, with two or three branches.
Very close to .S. denticiilata is S. florea, which has well-developed, hook-shaped, denticles, 1 — 2 spines, typical avicularia and the oa'cia immersed in the avi- cularia, whilst the ocecia are immersed in the ordinary zooecia in S. dentigera, S. spinuligera and S. serrata^, the last of which lacks the denticles, unless, as in the above-mentioned species from Victoria, they are here also so small that they cannot be seen from the surface of the colony. This last species, in which the aui- cularian mandible is much more beak-like than usual and elongated, is very variable in regard to its armature, as within the same colony we can find zooecia with 1 — 2 or with numerous spines, widened at the end and branched two or three times.
The above diagnosis has been designed so as also to include ^Membramporu< flustroides and Fl. octodon^, but the connection of these two species, and especi- ally the last, with the others is not without some doubt. Instead of the typical, beak-shaped, elongated avicularian mandible they have rounded ones, and in the case of Fl. oclodon it is really only the elongated form of the zoa'cia and the possession of, for a Fluslra, an unusually large number of spines, which can be taken as in favour of its relegation to the genus. Besides the presence of nume- rous rosette-plates and spines, the fact that some of the owcia are enclosed in avicularia, a character not found outside the genus Spiralaria, is in favour of the relegation of M. flustroides to the genus.
Retiflustra n. g.
(PI. I, figs. 6 and 7, I'l. XXI, ligs. 1 and 2).
The distal wall, at any rate in the ooecia-bearing zoa-cia and in most cases also in the others, meets with the basal wall of the colony in an angularly bent or curved line; the free edge of the owcia, which are placed on the frontal side of the colony, is much lower than their basal edge; the zooecia have no spines;
' 2, p. 49. ' GI, p. 1.31 .iiul 04. p. ;i " 2, p. 49.
127
the colony is strongly dichotomously branched with generally the branches con- nected so as to form an open network. Radical fibres arise from the marginal belt consisting of kenozooecia in the approximal corners of the angles of the branches.
It is possible that we may be able to add to this diagnosis still one or more characters, taken from the structure of the auicularia ; but for the present I only know the structure of the avicularia in the new species R. Schonaui.
R. Schonaui n. sp.
(PI. I, figs. 7 a-7 d).
The zooecia are of somewhat variable form, in most cases elongated, rect- angularly oval, with a distal curved margin, often a little irregular, especially in the marginal portion of the branches. There is a more strongly developed crypto- cyst than in any other member of tlie family. It appears as a marginal region along the whole extent of the zooecium and shows distinct belts of growth; these are specially obvious in the strongly developed proximal region. The larger part of the basal wall of the zooecium is uncalcified and has an oval form (fig. 7 d), only a belt along each side and a larger or smaller (Vsth — ^Ui'd) proximal por- tion being calcified. Owing to the slight strength of the calcification this oval only becomes distinct after it has been boiled in potash and only with reduced light. The calcareous part of the basal wall of the zooecium, and especially its proximal part, shows occasionally a number of transversely or obliquely placed coarse strije.
The distal wall, which is angularly bent and saddle-shaped in the direction from front to back, is furnished, with a transverse row of 6 — <S uniporous rosette- j)lates, while the distal half of each side-wall has 2 — 4. Partly owing to the saddle-shaped curvature of the distal wall, partly because the basal edge is placed higher than the frontal, we can see a large part of the under side of the distal wall from the basal aspect of the colony. The branches are everywhere bordered by a narrow marginal region, which here and there shows an inner separating wall, and must be regarded as formed by kenozooecia. It is only at the point where the branches bifurcate, consequently at the two ends of the oval perfora- tions, that this region has a larger extent and shows basally a gymnocyst and on the frontal side a cryptocyst with belts of growth. Here and there a radical fibre issues from the approximal corner of such a perforation.
The avicularia (iig. 7 a) are very rare, and I have altogether only seen two. They are of the same size as the zooecia, pointed proximally and almost pear- shaped. Contrary to the rule in Malacostega, they are far proximally provided
128
with a calcareous transverse bar and with a small cryptocyst. Only a short proxi- mal portion of the mandible was preserved.
The ooecia are low, bowl-shaped, and except in the (piite young are covered by a cryptocyst-belt in the proximal portion. The basal edge of the distal wall, from which the ooecium issues, is placed higher than the top of this, and can therefore by a deep focussing from the frontal surface be seen distally to the ooecium. Such distal walls have the same saddle-shape as the others, and are like these furnished with a row of uniporous rosette-plates.
The colonies are composed of circular fenestrate lamin.T?, superimposed one upon the other, and growing spirally from a common centre, one from the other. The fenestra; are oval, somewhat pointed and generally much broader than the segment between them.
The larger part of my material however consists of isolated fragments, and only a single fragment shows three connected laminae.
The species comes from the China Sea, lat. 26" 30' N. long., 121" 10' E., 42 fathoms, and has been taken by Telegra[)h-Engineer Schonau.
R. cribriformis Busk. Carbasea cribriformis Busk, Challenger Zoology, Vol. X, Part. I, pag. 58, PI. XXXIX, lig. 8. (1^1. I, CiHs. (i:i-61), 1>1. XXII, li^. 2 a). The zooecia have a very variable form, most often elongated hexagonal, oflen rather irregular, wilh a straight distal margin. There is a faintly developed cryp- tocyst in the form of a narrow marginal expansion, the proximal i)art of which is a little more developed. The basal side of the zooecia, which is more calcified than in the foregoing species, has a narrow, median uncalcified, longitudinal belt, which begins at the angle of the distal wall and as a rule reaches almost to the middle of the zotrcium. It is generally narrowest at the middle and widest proximally. On both sides of this we generally find a nundjer of transversely or oblicjuely placed, coarse stri;c, which in difl'erent zooecia may have a very dilTe- rent strength and occupy a very different part of the basal side, and which aiT in reality more calcified and thickened regions of this. In a fragment from Port Darwin this system of stripes is so strongly developed wilh such a pronounced whitish colour, that the whole of the basal side of the colonv' seems even with naked eye to be spotted with white. Besides the longitudinal belt mentioned this fragment by reduced light under the microscope shows a large, pear-shai)ed, dark spot, the proximal border of which meets with that of the longitudinal belt, but is broader than this. It arises from the contrast between a more strongly
129
calcified outer and a more slightly calcilied inner (median) part. The distal wall is acute-angled and the two arms are a little concave. As in the loregoing species, it is at the same time saddle-shaped, and furnished with a transverse row of (up to 12) uniporous rosette-plates. The distal half of each side-wall has ca. 6 rosette-plates. The marginal region, which consists of kenozoo'cia, only differs from the marginal region in the preceding species by the part, which ap])ears on the basal side of the colony, being much calcified and furnished with similar stripes to the zowcia. On the other hand, it has no distinct cryptocyst. The radical fibres issue from the proximal corners of a number of fenestrse.
Avicularia have not been found hitherto.
The ooecia are high, dome-shaped, with indistinct radiating stria? and gener- ally in the middle provided with a shorter or longer, sometimes rather irregular ridge. A low cryptocyst belt covers their |)roximal part. Also here the basal part of the distal wall lies higher than the top of the ocecium and is thus seen dis- tally to the latter at a deeper level (PI. I, fig. 6 b, PI. XXII, fig. 2 a). The distal wall belonging to the oa>cium forms an angular .or sometimes almost arched mark on the basal side of the colony, and the two arms are not concave but convex. The ocecia-bearing zoo'cia are, when looked at from the basal side, larger than the others, and the distal half of the above-mentioned uncalcitied longi- tudinal belt is generally very broad.
The colonies have the same slruclure as in R. Sclwiuun, l)ut the fenestrje are very much smaller and generally much narrower than the segments between them.
Of this species I have examined a fragment from Torres Straits (Cambridge) and one from Port Darwin (Ihitish Museum).
R. reticulum Hincks.
Flustra reticulum Hincks,
Annals Nat. Hist. .ser. o, Vol. X, 1882, p. 163, PI. YII, fig. 4.
(I'l. XXII, lij^s. la-lc).
The zooecia of rather varying form, most often irregularly pentagonal or hexagonal with an evenly rounded frontal edge. A cryptocyst appears as an extremely slight marginal expansion. The basal wall is uniformly, but not strongly calcified with the exception of a rather small, round (circular, oval or pear-shaped) uncalcified spot almost proximally to the distal wall. Very rarely a few short, coarse stripes appear here and there. Contrary to the case in the two other species the distal wall is generally straight in the ordinary zocrcia, and it has about 10 uniporous rosette-plates, some of which are placed opposite
9
130
each lateral margin. The distal half of each lateral wall has 5 — 6 rosette- plates.
Avicularia wanting on the fragment examined. They have been described and figured by Hincks, but require a closer examination.
The ooecia are rather large and not rarely of an outline describal)le as quadrangularly rounded. Along their proximal margin two indistinct cryptocyst processes are seen, which are rather large at their starting-point but quickly become very low. A little distally to the proximal margin of the oo-cium an extremely small pore is generally seen in the central line surrounded by a thickened portion, and from Ibis a number of partially coarse striae radiate. In contrast to the distal wall in the ordinarj' zooecia the ooecia-forming distal wall meets the basal wall of the zocrcium in a curved line, which is sometimes on a level with the top of the ocecium, sometimes somewhat lower than the latter, but at all events considerably higher than the proximal margin of the ocecium. Contrary to the case in the two foregoing species the whole of the distal wall is transformed to an oaH'ium. It is accordingly convex in its entire extent and has no saddle-shaped basal part with rosette-plates.
The colonies, which are branched dichotomously, differ from those in the two preceding species therein, that the separate branches do not meet. The marginal portion, which consists of kenozoa'cia, is wholh' calcified on the basal side and most thickened in its outer half, for which reason the colony is seen surrounded by a white margin.
I have examined a fragment of this species from Victoria (The Zoological Mu- seum of Cambridge, Dr. S. Harmer).
Family Scrupocellariidae.
Cellulariidae Hincks. (Pis. II iirid XXII).
The zooEcia are as a rule strongly calcified, with a membranous frontal area occupying a larger or smaller part of the surface. An arched gymnocysl of larger or smaller extent is found in most species proximally to the frontal area, and there is usually a more or less well-developed, most often finely granular second- ary cryptocyst. The margin of the aperture has as a rule 1 — 2 pair of spines distally, while from the approximate centre of the inner margin a spine, plate- like widened oi- branched at the end, very often arises and may cover a larger or smaller part of the frontal area. The distal wall, consisting of a horizontal basal and an obliquely ascending frontal part, has usually numerous, small, scattered, uniporous rosette-plates basally, while the distal lialf of each lateral
131
wall has one multiporous plate. Besides dependent auiciiliirid, found in most species, vibraciila may also occur on the hasal surface of the colonj% and these are connected with the colony by an independent wall. The oa'cia are generally hyperstomial with a wholly or partly calcified ectoooecium, more seldom endo- zod'cial. In the latter case they are sometimes enclosed in kenozooecia. As a rule radical fibres occur, sometimes springing from a rosette-plate (or a pore-chamber), sometimes from a separate chamber connected with a vibraculum. The colonies are always free, very branched, most frequently with uni- or few-seried zocecia, generally consisting of a single layer and in most cases jointed by means of chitinized transverse belts.
While a smaller number of species (e. g. Hoplitella arniala, Menipea flabellum, Men. spicata'^ and the Canda species), have a membranous frontal area, occupying the whole or almost the whole of the frontal surface, a larger or smaller part of the latter is in the other species occupied by an arched gymnocysl which in some species (e. g. in Menipea aculeittd Busk and Men clausa Busk) may be up to two- thirds of the length of the zooecium. While the cryptocyst in many species (e. g. in the Scruiwcellaria species, in Caberea Ellisi, Menipea acnleata, M. cirrata, M. palagonica) forms only a small depression in the margin of the aperture, it may in other species fill a larger part of the aperture inside the membranous fronlal area in the form of a somewhat depressed, generally finely granular lamina. This cryptocyst attains its largest extent in Menipea spicata, Caberea Darwini and in the Canda s|)ecies, but also in Men. flabellnm, Men. rohorata (figs. 7 b, 7 c), M. crystallina, M. liuski and several other Menipea si)ecies it may attain a consider- able development. We have already mentioned that a number of species possess a wholly chitinized, simple o[)erculum. As in Dimorpbozoum nobile and Dendro- beania Murraijana the distal wall consists of a basal, horizontal or slightly obli- (pie and a frontal, strongly ascending i)art (PI. II, figs. 7 g, 7 h, 8 c), but while in these two species the former portion is furnished with a single, large, multi- porous rosette-plate, it has generally in this family a great number, of single- [)ored plates which are variously grouped. On examining a zocrcium from the frontal surface (PI. II, fig. 7 a), the horizontal pore-bearing i)art of the distal wall is seen at a deep level at some distance proxinially to the distal end of the zool;- cium, and this is seen most clearly after a previous boiling in caustic potash. The avicularia always have their inner wall in common with Ihe zooecium on which they are placed; but as I have succeeded in isolating Ihe vibracula in some species {Caberea Ellisi, Canda arachnoidea, (kiberiella benemnnila, Scrupo-
' 69, p 132.
9*
132
cellaria scahrd) it seems natural to suppose that these hefeiozoa^cia in this family always have an inner wall of their own. In Caherea and CaberielUt I have found a septum dividing the vibracular chamber into two, of which only the distal may contain the muscles. While the od'cia in the majority of this family are hyperstomial, they are endozooecial and more or less deeply immersed in Biujii- lopsis Peachi, Ihigulopsis cuspidala, Menipea criistdllina, M. cernicornis, M. Biiski. M. triseriata and M. spicata. In M. crystallina they are enclosed in kenozoa'cia with a large membranous frontal area, while in the others they are immersed in ordinary zoa'cia, in such a way, however, as to appear more or les promi- nent on the zooecial surface. In M. Hiiski and M. cervicornis the distal part of the ocHcium is covered by a granular cryptocyst. In a smaller number of species the ectood'cium is wholly calcified, e. g. in Scriipocellaria levnatu^, Scrupocellaria reptans and Scnip. scruposa, but in most cases a larger or smaller [iroximal part is membranous and accordingly appears as a rounded or triangular area, clearly distinguishable from the calcified distal part. This is seen e. g. in Caheriella benemiinita (PI. XXII, fig. 8 a), Menipea roboratu (PI. II, fig. 7 a) and M. ligulata (Pi. II, fig. 8 a).
This famih' is one of the most natural and most sharplj' delimited, and the differences shown by the zooecia in respect to the armature of spines, develoj)- ment of gymnocyst and cryptocj'st etc., are all subject to such great variation from species to species that no generic importance ought to be attached to them. The division of the genus has therefore hitherto been based chietlj' on the struc- ture and appearance of the heterozooecia, and for the present I am unable to delimit them in a more natural way. In earlier as well as in more recent times attempts have been made to divide the large genus Menipea, e. g. by Gray, Mc Gillivray and Waters. But as I consider it superfluous to enter into a critical examination of the genera Emma' and Craspedozoum^, proposed by the two former authors, I shall limit myself to a closer examination of the divisions made bj' Waters^. This author discusses the subject as follows: »In the descri[)tion of the species, it is now shown that in the Celhilariidae there are two distinct kinds of articulation. In the larger number the new branch is given olf from a small chamber formed for the purpose. As the type of this section Menipea Baski is figured (PI. I, fig. 10); aiul I propose to restrict Menipea to those forms having this kind of articulation; and it will then include ^1/. Buski, Mac (1., ^1/. crystal- lina. Gray, M. njatluis, Thompson, M. ceri>icornis, Mac. G., M. conipacta, Mac. G. —
' In tilis species which has hitherto Ijccmi referred to the genus Meiiijwa, I liave found a viliia- cuhiiii, but without nagcllum. - 2, p. 27. " G9, p. 131. ' 111, p. 2.
133
On the other hand, probably M. cirrntd, Lamx., M. gracilis, Busk, M. patagonica, Busk, M. fimiciilata, Mac. G., M. triseriatd, Busk, M. flabellnm, L., M. ternata. Ell. & Sol., must, on this account, he elsewhere located; and in fact, before noting this distinction, it had been felt, that several species should be removed from the genus«. In another section, including ScT((/)oce//f/r/«, the jointing consists of nothing more than a partial breaking through or thinning of the walls of the zocecia near the commencement of the branch. In the zocecia in which this breaking through of the wall of the zoa^cial chamber has commenced, the polyp- ide is seen unalVected, parth' above and partly below this incipient division (see PI. I, figs. 11, 12). < In a subsequent work' he calls the group of species to which M. flabellum belongs by the temporary name Flabellaris.
In all Bryozoa that occur in jointed colonies, the jointing takes place in the same way, viz. the following. The zoa'cia, which are situated on the boundarj' between the two joints and which we may call 'joint-zooecia< , have a shorter or longer, wider or narrower, uncalcified, chitinized and accordingly flexible trans- verse belt, which may sometimes be situated more distally, sometimes more proximally, but which alwavs divides a joint zon?cium into a distal and a proxi- mal part, each belonging to its own 4«i»4-. Thus, what Waters in Menipea Bnski and other species calls a small chamber,- is in reality only the proximal part of a joint-zoa'cium, and its proximal boundary is just the distal wall between the joint-zoa>cium and the zooecium on the proximal side of the latter. This arti- culation may show an apparent, but in fact very insignificant dilTerence, when the colony is regarded from the frontal side, as the outer joint-zowcium in such species as M. jhihcUum, M. cirrata, M. jxilagonicd etc. commences with a chitinized belt, while in such species as M. Biiski, M. ceruicornis and M. criisttilliiKi it begins with a small calcified portion, the '>chamber« mentioned by Waters. In this however M. cyalhits agrees with the species of the latter group, though as regards structure and form of colony it is more closely allied to the former. As mentioned before, the ooecia in a series of Menipea species are more or less deeply immersed but as a rule distinctly prominent on the surface of the zocecia. Even apart from the fact, that, by a division of the genus Menipea on the basis of this fea- ture, we should be at a loss what to do with the species lacking ooecia, it is evident, that such a division must seem rather unnatural, as M. cijathns, which has hyperstomial ooecia by this proceeding would be separated from such species as M. cerricornis, M. Buski and M. crgstallina, to which it is undeniably closely related.
' 112, p, (;72.
134
Synopsis of the genera.
1) On the basal surface a larger or smaller number of zocrcia with a vihraculum connected with a chamber, from wliich a radical fibre may issue (avicularia always present):
2) The true vibraculum (the chamber for the radical fibres not in- cluded) divided by a septum into a distal and a proximal space, the former containing the muscles:
'A) The very large, claw-shaped vibracula, present on all zoa'cia, are directed obliquely inwards and basally, and meet from both sides at acute angles in the middle of the basal side of the colony, which they almost cover; the flagellum on one margin generally with pointed teeth; the radical fibres, which spring only from the chamber con- nected with the vibraculum, run down along tiie middle of the basal side of the colony as a continuous, raised bundle; (the colony not jointed) Caberea Lamouroux.
3) The small, curved or angularly bent vibracula, not present on all zoa'cia, are far from reaching the centre of the colony; the fiagel- lum without teeth; the radical fibres, of whicii some spring from the chamber connected witli the vibraculum, others from a rosette-plate on the marginal zoa-cia, form a bundle along each lateral margin of
the colony Cnberiella n. g.
2) The true vibraculum not divided into two spaces (the llagelhim without teeth; the colony generally jointed; the vibracula covering only a smaller part of the basal surface of the colony):
4) The od'cium enclosed in tlie widened proximal half of a large avicularium, the distal, cap-like part of which bears the mandible and encloses the muscular apparatus. The frontal areas of the two rows of zooecia meet at obtuse angles; the radical fibres, given off from and ending in a chamber connected with the vibraculum, form jjarallel connecting threads between the neighbouring l)ranches (Ainda Lamouroux.
4) The oo-cium not enclosed in an avicularium; the frontal areas of the two rows of zotrcia on the same level; the radical fibres form no parallel connecting threads between the neighbouring branches. . . ScrupocclUiria
van Beneden.
1) No vibracula:
135
5) No avicularia; (the ocecia more or less deeply immersed in the
zooecia) Bugulopsis Verrill.
(Cellularia Hincks).
5) Avicularia occur:
6) Each marginal zooecium with a large marginal avicularium, the greater part of which is immersed in the zooecium and shows a strongly arched wall inside the latter; (the other zooecia with a completelj' membranous frontal area and no avicularia; no spines; no ocecia; tlie
colony with multiserial branches) Hoplitella n. g.
6) Where marginal avicularia are found they are never partially immersed :
7) A number of zooecia on one margin of the branches have two huge, hollow spines on the proximal side of the frontal area; (a free
stem formed by numerous radical fibres, etc.) Rhabdozoum Hinclcs.
7) No hollow spines proximally to the frontal area Menipea Lamouroux.
Caberiella n. g.
Small, narrow, curved or angularly bent inbracula appear on the basal side of a number of zowcia. They are divided into a distal and a proximal cavity by a septum and occupy only a small part of the basal surface of the colony. Avi- cularia occur. The radical fibres are given off partly from a chaml)er connected with the vibraculum, partly from a pore-chamber. They form a bundle along each lateral margin of the colony.
C. benemunita Busk.
Menipea benemunita Busk,
Challenger Zoology, Vol. X, Part 1, pag. 19, PI. IV, fig. 4.
(PI. XXII, fig.s. 8 a-8 h).
The zooecia are long and- narrow with a gymnocyst occupying about two- thirds of the entire length of the zocL'cium. There is a well-developed, deeply immersed, secondary cryptocyst, which is densely and finely granular especially in its distal half, and provided with a finely dentate inner margin. Right at the distal end it appears as a more deei)ly-placed, curtain-like lamina, the free margins of which end in 6 — 8 teeth. Besides the large, long, scutiform opercular spine, furnished with a bifurcate hollow and covering the greater part of the frontal area, the zooecia have 3 — 4 spines distal ly, one on the same side as the opercular si)ine and 2 — 3 on the opposite (i. e. outer) side. Three spines only on the nuirginal zoo'cia.
136
The avicularia, of which there are two i)roxinialIy to the frontal area, are in the oa'cia-hearing zoa-cia situated on the distal part of the ocrcium.
The vibracula are not found on all zoa-cia, hut seem to ai)i)ear rather fre- (juently and may be seen sometimes on 2 — 3 successive zooecia. They are narrow, most often angularly bent and situated in such a way that their inner part is turned obliquely inwards and towards the proximal end. A radical libre takes its origin from their outer part, while other radical fibres spring from a pore- chamber in the zooecia, that have no vibraculum.
The ooecia are provided with fine radiating striae, and the largest part of the ectooa-cium is uncalcified. The calcified jjart terminates in a somewhat projecting, angularly bent or arched, often somewhat sinuated margin.
The colony is not jointed. Its branches may have up to 7 rows of zooecia.
By way of exchange I have acquired a small fragment of this species (from Challenger, St. 313) from the Zoological Museum at Dundee.
Hoplitella n. g.
Avicularia appear only on marginal zoaxia which all have a large avicularium, the inner half of which is immersed; the distal wall has on each side a long, narrow continuation running along the corresponding lateral wall; the entire frontal surface membranous; no oa'cia; the colony not jointed.
H. armata (Busk).
Carbasea armata Busk,
Catalogue of Marine Polyzoa, Cheilostomata, p. 50, PI. L, figs. 1, 2.
Flustra armata Waters, Jom-n. R. Micros. Soc, 1899, p. 279— 2Sfi. (I'l. II, figs. l();i — lOo). The zooecia, the entire frontal surface of which is membranous, are rhombic- like oval, each of their lateral margins, when seen from the frontal side, ending in an almost rectangular edge, bounded l)y two curved lines. While this edge in the zooecia in the median part of the branch is generally situated a little distally to the centre on the inner and a little proximally to the centre on the outer lateral margin, it is, on approaching the margin of the colony, situated higher up on the former and further down on the latter, and this contrast is always greatest in the parts of the colony, which have the largest number of rows of zocecia. The marginal zoa^cia are much broader than the others, as they partly enclose the large avicularia, and as they stand in close relation to the avicularia, it will be more natural to treat them together with these. Immediately proximally
137
to the distal edge of the zooecium a large, semi-circular opercular valve is found. The basal horizontal part of the distal wall has a large, somewhat curved trans- verse group of up to 70 uniporous rosette-plates. On the boundary between the horizontal and the obliquely ascending part of the distal wall two narrow, tubular cavities issue (figs. 10 b, 10 d), which from each zooecium sink down into the subjacent one. They are bounded outwardly by the lateral wall of the zooe- cium and inwardly by a continuation of the distal wall, and in a transverse section proximally to the latter they are seen as two small, round holes (fig. 10 c). They touch the basal edge of the rosette-plate of the lateral wall and generally end just proximally to it (fig. 10 d). On the basal side of the colony the edge of the distal wall shows a number (6 — 10) of small, distally pointing, short, broader or narrower, sometimes bifurcate crenulations (figs. 10 b, 10 c), which are really outpushings from the lower into the higher placed zooecium, and alternating with them is seen a number of much more faint ones pointing proximally.
The avicularia, only occurring on the outer lateral margin of the marginal zoa'cia, are very large, turned towards the frontal surface of the colony and furnished with a well-developed beak and mandible hook. A great part of the avicularian cliamber is enclosed in the zooecium, and its strongly arched endozocecial surface lias about 10 scattered, uniporous rosette-plates (fig. 10 e). The marginal zooecia have an obliquely triangular transverse section, ending outwards in a rounded edge, and (he outer of the two above-mentioned, narrow lateral cavities passes obliquely across the basal side of the avicularium, being only visible from the basal surface of the colony. On the basal side the zooecium is separated from (he free part of the avicularium by the just mentioned cavity, and on the frontal side by its upper lateral margin, which runs obliquely outwards to a small indentation in the approximate centre of the lateral margin of the avicu- larium. A corner is formed here corresponding with that of the other zoa'cia. In the outer half of a marginal zocrcium we may distinguish between a frontal and a basal, distal lateral margin, which together enclose the avicularium and mark the boundary between the free part of the latter and the part immersed in the zoa'cium. On Ihe other hand there is but a single proximal lateral margin, as the frontal and the basal lateral margins are here run together in an edge. Instead of the calcified lateral wall in the other zoa-cia we thus find here but a strongly calcified rib, which however generally shows a distinct separation into two lateral halves, enclosing between them a rosette-plate (fig. 10 e).
No ooecia.
The colonies are unjointed, single-layered, dicholomously branched with
138
5 — 14 rows of zooecia in the separate segments. The radical fibres spring from a pore-chamber in the proximal part of the marginal zocecia. In the older part of the colony they form a Hat bundle on the basal surface, immediately within each lateral margin, with oblique transverse connections at the base of the sep- arate segments.
The colonies examined originate from ('ape Town.
Menipea Laniouroux.
It will be evident from the above summary of the genera that the genus Menipea like the genus Heteroflustni is only negatively characterized, as it com- prises all the species that cannot be referred to any of the other genera.
M. roborata Hi neks, Membranipora roborata Hincks, Annals Nat. Hist. ser. 5. Vol. VIIl, 1881,
pag. 128, PI. 2, fig. 3. Flustra membraniporides Busk, Challenger, Zoology, Vol. X, pars 1, pag. 54,
PI. XXXII, fig. 7. Flabellaris roborata Waters, Journ. Linnean Soc, Zoology, Vol. XXVI, 1898, pag. 672, PI. 48, figs. 10—11; PI. 49, figs. 7 — 11. (PL II, figs. 7 a-7 k.) The zooecia long, hexagonal or hexagonally vase-shaped, often with an acutely projecting corner between the distal and the proximal part. The gymnocyst is very slightly developed on the zocrcia with no avicularia (e. g. some marginal zott'cia) and may on those with avicularia occupy about one-fourth of the whole length of the zooecium. In the entire periphery of the frontal area a distinct, granular cryptocyst is seen, deeply immersed and strongly developed especially at the proximal end, and attaining its highest development in the marginal zoav cia. There may be four spines distally. The two central ones are very small and bud-shaped, but often wanting, while the other two are rather short, as a rule present, but often wanting in the marginal zocrcia. The marginal zocrcia, which are larger but rarely longer than the other zoa'cia, are very asymmetrical and their obliquely oulbending lateral wall has a straight or slightly convex frontal margin. On isolating a row of zoa?cia after boiling in caustic potash it will easily be seen thai the inner surface of the zooecia (figs. 7 d — 7 h) has a some- what varying number of solid calcareous processes of dilTerent length and thick- ness, of which generally 1 — 4 may be seen through each lateral surface. In many zooecia a larger or smaller part of such a calcareous process may protrude on
139
each side of the proximal pari of the aperture distally to the cryptocyst (figs. 7 b — 7 c). The basal, horizontal part of the distal wall has a transversely oval or triangularly rounded, multiporous rosette-plate, generally with a frontal concavity (figs. 7 f, 7 h). In most zooecia the distal wall between the rosette-plate and the basal wall is provided with a little rounded (sometimes two) pore-chamber de- scending into the lower zocecium (figs. 7 d — 7 e) and in its bottom furnished with one or more small uniporous rosette-plates.
The avicularia occur in two different forms of which one is found in the cavity of the zorecium, while the other in zooecia without oa?cium is found on the proximal side of the membranous area, and in ooecia-bearing zooecia on each side of the distal part of the ocecium. The external avicularium, which has a well-developed hook as well on the mandible as on the corresponding part of the chamber, is placed so, that the mandible is turned obliquely outwards and distally on the ofrcia and obliquely inwards and proximally on the zooecia. The boundary between the opercular and the subopercular area is formed by two nearly always concurrent, narrow, cylindrical, generally bent and often very ir- regular processes, of which one is usually longer than the other (figs. 7 c, 7 i). On the proximal side of the frontal area we find very seldom two, generally but a single avicularium which is then most often situated on the outer side (the one nearest the margin of the colony) and occupying more than half the space. If found on the marginal zooecia it is however placed On the inner side, the reason of which may l)e, that there is a large pore-chamber on the outer side, from which a radical fibre takes its origin. In the ordinary zooecia, at the proxi- mal end of which there is but a single external avicularium, and in the marginal zooecia with no external avicularium, an internal one is always found, arising from the internal side of the surface which from its position seems intended to have an external avicularium. The latter, which has both a mandibular and an avicularian hook, is oval, with the mandible pointing obliquely distally and in- wards, and with but two short teeth on the boundary between the opercular and the subopercular area (figs. 7 d, 7 e, 7 g, 7 k).
The ooecia are rather high, rounded and the ectoooccium has a proximal, rounded triangular, membranous area, while its calcified part terminates in a somewhat projecting, angularly bent margin.
The colonies are bilaminate, dichotomously branched and their branches have up to Hi rows of zooecia. A bundle of radical fibres springing from the pore-chambers in the proximal part of the marginal zooecia runs along each lateral margin.
140
I have been able to examine a colony IVom Napier, New Zealand (Miss Jelly) and another from Port Jackson, New South Wales (Mr. Waters).
M. ligulata M. Gill.,
Craspedozoum ligulatum M. Gill., Transact, and Proceed. R. Soc. of Victoria,
Vol. XXII, 1886, pag. 132, PI. I, fig. 3.
(I'l. II, li^s. 8a-8c).
In respect to form and development of spines, gymnocyst and cryptocyst the zooecia essentially agree with the foregoing species. The marginal zoo^cia are however generally furnished with all four spines, the two on the outer margin attaining the greatest development. A rather long, calcareous process, pointing basallj' and obliqueh' proximallv, springs from the inner surface of the frontal wall on the proximal side of the zooecial npening It consists of a long, narrow, compressed rod, terminating in a quadrangular expansion with a finely dentate and striated margin (figs. 8 c, 8 e). This expansion again is composed of two unequal lateral halves, bent against each other in the shape of a roof, with the hollow downwards. These processes, which can easily be seen through the wall when an isolated row of zooecia is viewed from the side, are subject to some variation, both as regards the absolute length and the proportional size of rod and terminal expansion. The lateral walls on the other hand have no processes. The distal wall has a large, broad, multiporous rosette-plate (fig. 8 d) deeply sinuated frontally, and as in the foregoing species we find one or more pore- chambers (fig. 8 d) between the rosette-plate and the distal wall. These are however generally larger and often of a peculiarly sinuated or twisted form (figs. 8 b, 8d).
The avicularia, of which only a single form is found, have a long, narrow, triangular, j)ointpd mandible and two small hinge-teeth on the boundary between the opercular and the subo])ercular area. In the zoa'cia without ocrcia there is generally only a single, rather large avicularium |)roximally to the membranous frontal area. It occupies the whole space in the proximal part of the zowcium, and has not as in M. roborala a distinctly delimited, but em|)ty area at the side. The mandible is most frequently turned to one of the sides. There is no internal avicularium, but in some few cases a small avicularium occurs in the distal part of the outer margin of the marginal zoa'cia. Above each od'cium generally two small avicularia with the mandible turned obliciuely distaily and outwards.
The ooecia have as in the preceding species a proximal, membranous area which is here rounded and not bounded by an angularly bent distal margin.
141
The colonies are imilaininate, dichotomously branched and their branches have up to 8 rows of zooecia. They are as in the foregoing species bordered by a belt of radical fibres.
Of this species I have examined some colonies from Napier, N. Zealand, for which I am indebted to Miss Jelly.
Canda Lamouroux. (PI. II, fig. 9 a).
The zoa'cia are on the basal surface furnished with a inbraciiliiiu which (apart from the adjacent chamber of radical fibres) only contains a single cavity; the flagellum is not dentate. The frontal areas of the two rows of zoa^cia form obtuse angles with each other, and the neighbouring branches of the fan-shaped colony are connected by parallel radical fibres, which are always given off from or terminate in the chambers connected with the vibracuhi; no marginal uui- ciiUiria.
The zoa>cia have at the distal end a shorter or longer spine on each side. They have no frontal gymnocyst, the calcification of the frontal surface being exclusively formed by a more or less granular, asymmetrical, deepened crypto-, cyst, the extent of which is ditTerent in the various forms. The on>cia are endo- zocjecial, being enclosed in avicularia, and in the latter we may thus tlistinguish between a proximal, wider j)art, the ectoooecium, whose frontal wall is furnished with a rounded, uncalcified portion, and a distal, cap-shaped part, the real avi- cularium. The boundary between the two parts is formed by an angularly bent transverse belt in which the ectooa'cium and the endoooecium have coalesced. To communicate with tlie avicularium the zoo^cium has a small rosette-plate.
Of this genus four species have hitherto been described, chiefly on very rela- tive characters and without any large material, and it may accordingly be diffi- cult to decide for certain, how many of these species are maintainable. Our Mu- seum is only in possession of a plentiful material of a West hidian species, besides a colony from Bass Straits of C. arachnoides and a small fragment of C. retiformis, sent from the British Museum. From the same Museum I have bor- rowed a preparation of (lundu siiuphw Busk, for examination, but it was covered with heterogeneous bodies to such an extent, that it was imjiossible for me to decide whether this form, as I think probable, is identical with the above-men- tioned West Indian, which accordingly I must give a special name.
On the basis of this material I may now give the following synopsis of the Canda species.
142
1) The colony jointed, the two inner zooecia in each bifurcation being divided into a distal and a proximal calcified portion, connected by a chitinous tube; the vibracula far from reaching the central suture of the branch. (The cryptocyst occupying about one-fourth of the whole length of the zoa^cium. The proximal margin of the vibraculum sei)a- rated from the distal wall on the jjroximal side of it by a distance which is at least half as large as the breadth of this wall; not in- frequently avicularia along the middle of the branch; no opercular spine) C. arachnoUes Lam.
1) The colony not jointed; the vibracula almost reaching or sur- passing the central suture of the branch ;
2) The zooecia with a hammer-shaped ojjercular spine; the proximal margin of the vibraculum is separated from the distal wall by a dis- tance which is about half as large as half the breadth of the latter; the vibraculum almost reaching the central suture of the branch; the cryptocyst is a little shorter than half tlie lengtli of the zo(r-
cium C. retiforinis Smitt '.
2) No opercular spine; the proximal margin of the vibraculum almost reaching the distal wall; the vibraculum reaching or surpassing tiie central suture of the branch; the cryptocyst occupying about one- third of the whole length of the zouicium C. caraihica n. sp.
? C. simplex Busk'-.
V C. tenuis M. Gill.l
On account of the remark made l)y Husk", that the avicularia in the sutural line of the branch in C. arachnoides do not seem Id be developed in connection with the separate zocrcia, I may here call attention to the fact that Husk is wrong in his supposition. On splitting a branch into its two lateral halves it will easily be seen that lliese strongly compressed avicularia are given off from the free continuation of the inner lateral nuugin of the zoa^cia.
Rhabdozoum Wilsoni Hincks, Annals Nat. Hist. V Ser., Vol. X, pag. 160, PI. VIII, fig. 4.
This peculiar form, of which I have been able lo examine specinuMis from Western Port and Port Phillip, Victoria, which I owe to the kindness of Mr. J. Gabriel and Miss Jelly, is by Hincks wrongly referred to the Eiicniliidac, a
' 102, p. 16. - 8, p. -JG. ' (i8, p. 107.
143
family including some of the genera which have been referred by me to the family Bicellariidae. That it must be referred to the Scrupocellariidae and not to the Bicellariidae is sufficiently evident from the stronger calcification and the structure of the distal walls, the auicularia and the owcia. The last mentioned, which are hyperstomial and the basal wall of which is a part of the frontal wall of the zoa-cium, have a mostly membranous ectoooecium, which has only a calcified marginal portion. The frontal gymnocyst is unusually large, whereas there is but a very slightly developed secondary cryptocyst, which in the oldest zocecia terminates in a number of tooth-like processes. The basal wall of the zooecia is acutely arched, transversely striated and each radical fibre takes its origin from a [)roximal pore-chamber.
Family Membraniporidae.
This family comprises all the Malacoslegous forms which can neither be refer- red to the Cribrilinidae nor to any of the above-mentioned iiimilies, and which in contrast to these can only be characterized negatively, viz. l)y their not possess- ing the combination of characters peculiar to any of the above families. It shows greater variation and wider contrasts than any of the other Malacostegous families.
The frontal wall of the zoacia is sometimes quite membranous, sometimes to a greater or smaller extent provided with a calcareous layer, which may be sometimes a gymnocyst (Electra), sometimes a cryptocyst (e. g. Omjchocella) and most often a combination of both. Spines are sometimes wanting, sometimes found in great numbers in the whole periphery of the frontal area. The separate zooe- cia communicate sometimes by uniporous or multiporous rosette-plates, some- times by pore-chambers. The heterozocecia have in some cases a calcified trans- verse bar and may appear both as avicularia and as vibracula. They are sometimes independent (vicarious), sometimes dependent, and sometimes both forms are found together (Callopora craticula). The ocEcia are usually hyper- stomial, in a single genus acanthostegous and in some cases endozoa-cial {Cale- schara Rosseliana), sometimes (Oochiliiui) surrounded by kenozoa>cia. The colonies are most frequently incrusting, but in many cases free and then either laminate or forming richly branched tufts. Within this seclion so rich in species no small number of genera and a few families have subsequently been set up or proposed, e. g. by Busk, Waters, JuUien, Norman and others. Neither time nor my material permit me to give a criticism of all the genera proposed, but I must confine myself to set up a few new ones and to give new diagnoses of some older ones. A grouping of the numerous species described, according to their
144
relationship, will require a considerable amount of work and much critical sense on account of the great variation within a series of structures.
Membranipora L.
Billuslra d'OrJj (p. p.), Busk, Smitt. Nichtina Canu.'
The zuwcku the aperture of which is to a greater or smaller extent surrounded by a granular or denticulate, cryptocyst margin, have 2 spines at most, which are situated in the two jjroximal corners. On each side of the distal wall one niultiporous rosette-plate or a series of uniporous or partly multiporous; each lateral wall with 2 — 4 multiporous plates. No aincnUtria; no owcia.
In M. nicmhrdnacea the cryptocyst appears only as an extremely narrow mar- ginal portion, while in other si)ecies it attains not only a greater breadth, but also forms a large, proximal expansion, often terminating in a larger or smaller process. This is most strongly developed in M. ilenticulald (ilanica) v. sciiliitd'-, in which it almost reaches the operculum as a free, quadrangular lamina. It is less developed in M. delicatiila Busk. The cryptocyst attains its highest develop- ment in M. ohionya Busk', which represents a Micro/;or(/-like development of the genus. The two spines, which constantly appear in M. membranacrd and in M. tuberciilala and which in a number of species are more or less tuberculiform, attain their highest development in the latter species, in which they often coal- esce into a single very large tubercle, and a similar coalescence takes jjlace in a number of zocecia of ^1/. Lacroixi Aud^ (non Busk, nee Hincks), ligured by Savigny, the spines of which generally seem to have a triangular transverse section. In M. Savarti and M. denticiihita these spines are not constant, and in a series of undescribed forms, which must be referred to other species, they are altogether absent. In my description of M. membranacea in »Zoologia Danica* I have already called attention to the great variation in the rosette-plates of the distal wall in this species. On either side there may be sometimes a large multi- porous rosette-plate, .sometimes a series of smaller, uniporous or partly multi- porous ones. In all the forms examined by me multii)orous rosette-plates are constantly found on the lateral walls.
As in all the numerous forms, I have had the opportunity of examining, no ooecia were found, which however are said to be present in the species from
' 11 a, p. 380. '■' 55, p. 54. ' 7, p. 34. ^ While the .species of Savigny is furnlslicd with two spines which in some zocecia are coalesced into a semiglobo.se tubercle the species, wliiih lliiicks calls Memb. iMcroixii, lias a greater or lessci' luinihei' of small triangular hollows Uc'nozo<t'eia between the zoa'cia.
145
Florida, determined liy Smitt as ,1/. Lacroi.vi, I must dispute the correctness of
S mitt's determination. The unpaired swelling mentioned before, which is found
in the proximal end of some zocecia In M. Lacroi.vi Aud. \ Smitt" explains
as ooccia, which have been placed in an inverted jjosition by Savigny's artist
(>drawer<); but there is, I think, no reason to doubt the correctness of the
figure.
Membranipora limosa Wafers.
Journ. Linnean Soc, Zoology, Vol. XXXI, 1909, p. 140, PI. 12, figs. 1—5.
(PI. XXII, figs. 5 a-5 c).
The zooecia, which are separated by distinct (in fresh colonies brown) sutures, are rather long, generally hexagonally rectangular with a curved distal edge. The narrow aperture, which is half as broad and a little more than half as long as the frontal wall, is provided with a semicircular oral valve. The whole of the calcified part of the frontal wall is formed by a cryptocyst, in which we can distinguish between a broad raised marginal portion furnished with parallel series of more or less coalesced tubercles, and of a depressed median pari, the distal margin of which is armed with a little process of varying shape, most often bifurcate, sometimes almost fan-shaped with a number of small projecting teeth. The obliquely ascending distal wall, the triangular basal part of which may be split into a distal and a proximal half after treatment with Eau de Javelle, has in its inner part two (more seldom three), fine, slender, erect, somewhat curved calcareous rods, bent at the end like hooks, which project inlo the proximal i)art of the distal zooecium and have the hooks directed away from the frontal wall. Each distal wall has in its inner, more horizontal part inside the posterior margin 6 — 7 uniporous rosette-plates or a smaller number of plates, of which some are multiporous. The distal half of each lateral wall has generally 2 (rarely a single) rosette-plates with 2 (1) — 6 pores.
The colonies unjointed, slender, richly branched, with bifurcate branches which bear from 4 — 5 rows of zocecia. The number of zocecia in the separate rows is from 4 — 14.
The Formosa-channel, 30 fath. (Suensson), Nagasaki (Suensson).
As M. meiubranacea L. must be regarded as the type of the above characterized genus, and the name Membranipora ought therefore in future to be used only in this more restricted sense, we shall want a name to designate all such species as cannot be referred to particular genera. As such a temporary name I propose » Membraniporina « .
' 98, PI. 10, fig. 9.2. '' 103, p. 18.
10
146
Electra Lamour.
Tendra Nordin. p. p., Pyripora Mc (^oy p. j).,
Heteroceciuni Hincks.
The frontal calcification of the zoa-cia is essentially or exclusively a gynino- cyst. There may be a circle of spines round the frontal area, of which an un- paired proximal one is generallj' the most constant and often the only one pre- sent. The distal wall is furnished within its proximal margin with a transverse row or a transverse belt of uniporous rosette-plates; the lateral walls have 2 — 15 multiporous plates. No anicularia. (hecia absent or acanthostegous.
To this genus I refer E. iwrticillala, E. pilosa, E. bellnUt, E. tiiacdiillui, E. lUstorla, E. zostericola, E. (imj)lectens, E. njonostachys, E. fossttrUi and E. catenu- luriii which like E. fossaria has a calcified operculum and can only be regarded as a form of the latter. I have .some doubt whether the species, which has hitherto wrongly been called M. Lacroixi, and for which I projiose the name of M. bippopiis, can be referred to this genus.
E. zostericola Nordmann. Tendra zostericola Repiacholf, Zeitschrift fiir wissensch. Zoologie, 25. B., 1875,
pag. 129, Tab. 7—9.
Membranipora (Tendra) zostericola Oslroumoff, Die Bryozoen der Bucht von
Sebastopol, pag. 18, Tab. 1, Fig. 13—14.
(PI. IX, figs. 2 a-2 b).
As shown by the above-mentioned authors there is among the ordinary zooecia, which have generally only two distal and sometimes one proximal, unpaired spine, a smaller number, in which as in the Mcinbraniporella species the mem- branous frontal area is covered by two rows (10 — 17 pair) of hollow, very thin- walled s|)ines, which meet in the central line of the zocecium. Their form is extremely' variable in the same zorecium, as they are sometimes broad, some- times narrow, sometimes single, sometimes bifurcate in a larger or smaller part of their length. Two opposite spines most often meet in a truncated terminal part, but it is not infrequent, that a greater or smaller number of them stretch a thin point across the end of an opposite spine. The bright spots seen at the outer part of each row are the translucent cavities of the separate spines. Of these the distal ones are the shortest, and the gymnocyst projecting here into a triangular portion, which has a curved margin distally, leaves a small trans- versely oval area for the opercular valve. The two rows of spines form a some- what arched roof across the frontal membrane, and thus a space is formed which
147
opens outwards immediately on tlie distal side of the operciiluni of the proximal zocEcium. These zooecia. of which several may sometimes occur in succession, are supposed by Repiachoff to be equivalents of o(rcia. But while according to the description of this author we should think that the cavity of the zooecium itself acts as oojcial cavity, Ostroumoff informs us of the fact, that the em- bryos and larva; are situated in the space between the spines and the frontal membrane. He speaks on this as follows': »The lattice-like zooecium (cellule treillissee Nordm.) serves as ovicell for the zooecium on its proximal side. The cavity of the ovicell is formed on one side by the surface of the mantle (i. e. : fron- tal membrane), on the other by the concurrent spines. The egg, which is ex- truded from the lower zooecium by the tentacles, comes into this cavity, and this may be easily seen by a transverse section through a lattice-like zooecium containing embryos. Some embryos are usually found in this cavity. « On my enquiry Ostroumoff has however informed me, that he has not observed such a transference of the egg. Besides the ordinary zooecia with 2 — 3 free spines a smaller number may be found, in which the frontal area is surrounded or par- tially covered by 1 — 9 pairs of spines of varying length, which however meet neither the spines springing from the same nor those from the opposite side.
A number of colonies of this species from Sebaslopol were kindly sent to me by Dr. OstroumotT.
E. (Heterooecium) amplectens Hincks. Membranipora amplectens Hincks, Annals Nat. Hist., ser. 5, Vol. VIII, 1881,
pag. 129, PI. Ill, fig. 7. Heterooecium amplectens Hincks, Annals Nat. Hist., ser. 6, Vol. IX, 1892,
pag. 195. (PI. IX, figs. 1 a-1 c). The ordinary zooecia are pear-shaped oval and provided with a membranous frontal area occujjying half the breadth of the zooecium and between half and one third of its length. It is surrounded by seven spines, of which six are short and a proximal one long and strong. From the inner surface of the frontal area more than 30 small dentiform processes issue, of which the two distal ones are the longest. They are arranged in an oval which is not entirely closed proxi- mally, and the distal half of which is immediately within the margin of the frontal area.
The ooecium-bearing zooecia are broadly oval and have somewhat proxi-
' 90, p. 19.
10*
148
mally to the centre an opercular valve, on the proximal side of which there is a long, strong spine. The two rows of flat spines, which cover the area on the distal side of the valve, generally meet in truncated ends. We may how- ever sometimes, as in the corresponding formation in E. zostericola, see a spine stretching its terminal part across an opposite s\nne. The basal wall is only calcified in the distal, ribbed half of the zoa'cium. A small piece of this species was kindly placed at my disposal by the late Mr. Peal.
Var. brevispina n. (fig. 1 c).
The ordinary zooecia are larger, narrower at the base, the frontal area sur- rounded by 8 — 9 short spines, the proximal one but slightly stronger than the others. The dentiform ]n-ocesses are represented by about 10 extremely small tubercles, situated within the margin of the frontal area in the distal half of the latter.
The orecium-bearing zooecia are larger than in the principal form, have fewer spines and a semi-circle of o short spines proximally to the aperture.
A few colonies of this form have been found on Honnophora Anstralasiae in the herbarium of alga; in the Botanical Museum. Although we do not under- stand the significance of the situation of the aperture behind the area formed by the spines, we must still group this form of oojcium with the one found in E. zostericola.
Electra bicolor Hincks.
Membranipora bicolor Hincks,
Annals Nat. Hist., ser. 5, Vol. VII, 1881, pag. US.
(PI. IX, figs. 7a-7c).
The zooecia very long, narrow (the length larger than the breadlli by about 3^2 times), somewhat lyre-shaped, with a longitudinally oval, membranous frontal area, occupying about three-fourths of the whole length of the zooecium and bounded by somewhat convex lateral walls. The smooth, arched gymnocyst passes into a cryptocyst, which first sinks obliquely distally and inwards and finally gives off towards the basal wall of the zooecium a horizontal lamina ending in a denticulated margin (fig. 7 c). On the boundary between the oblique semi-elliptical and the horizontal denticulate part of the cryptocyst a triang- ular calcareous lamina takes its origin. It consists of two lateral halves, bent against each other at an angle open outwardly, and which meet in a thickened central ridge (figs. 7 a, 7 b). In rare cases the gymnocyst has a small tubercle-like expansion distally. The frontal margin of the distal wall is strongly thickened and crenulated, and on the proximal side of it the operculum is seen
149
with a strongly chitinized margin. The lateral margins of the operculum form right angles with the distal margin. The distal wall has within its basal edge a transverse row of 3 — 5 small uniporous rosette-plates, while the distal half of each lateral wall has 2 multiporous ones.
The colonies examined form incrustings on Amansici pinnalifida from Austra- lia. (The herbarium of algaj in the Botanical Museum). This species is most closely allied to Membranipora nitens Hincks, which must also be referred to the genus Electra and shows more distinct signs of the relationship than E. hicolor. It has as in E. pilosa an obliquely ascending distal wall, and the three promi- nent spines, so often occurring within the genus, viz. the unpaired proximal and the two distal, are here represented, the former by the large conical expansion and the latter by two somewhat compressed tubercles, which are connected by an arch-like ridge. The rosette-plates are of the same structure as in E. bicolor.
E. angulata n. sp. (PI. XXII, fig. 4 a).
The zooecia of varying form and dimensions, with a distal arch-like or angulate margin and with a large, most often oval, membranous frontal area, occupying the greater part of the frontal surface. There is a slightly developed, granular, dentate, secondary cryptocyst. In respect to development of si)ines the zooecia show great ditTerences. The best provided ones, which in the colonies examined arc in a great minority, have on the margin 12 not very thick spines, which reach the middle of the area or even surpass it. A larger or smaller number of them is however often wanting, and many zoa-cia are altogether without spines. On the proximal gymnocyst we find in most zoa?cia 2 (more rarely a single median and still more seldom 3) short, thick, conical spines, generally open at the end, which are situated half-way between the central line and the lateral margins. These spines may sometimes be rudimentary, and in many zoa>cia (with or without marginal spines) they are absent. The distal wall, which is generally ascending towards the frontal surface and angularly bent from side to side or arch-like, has on either side a rather large, multiporous rosette-plate situated in one of the basal corners of the distal wall. The distal half of each lateral wall has a single multiporous rosette-plate.
On a ligneous core taken on the surface of the water near Koh Samit, Siam (Dr. Th. Mortensen).
In a variety of this species from lat. 22° 10' V. long., 114" 30' E. (Captain Suensson) the separate zooecia attain considerably larger dimensions and are in the examined colony all provided with 20 — 24 marginal spines and with 1 — 3
150
short and thick proximal ones. The distal wall is more bent (at a right or an acute angle), and the distal half of each lateral wall may have 1 — 2 rosette- plates.
In referring the species, described above, to Electrn, although the distal wall has two niultiporous rosette-plates instead of a row of uniporous ones, the reason is that the rosette-plates of the distal wall in many species show rather great variation even in the same colony. Otherwise this species is most closely allied to E. monostacliiis. The peculiar doubling of the j)roximal spine may possibly explain the origin of the two proximal corner-spines in Mcnihranipora lueiiihrdiui- cea and may then be considered as evidence of the development of Memhidiiipord (sensu stricto) from Electro. Both genera agree in jjossessing few multiporous rosette,-plates on the lateral walls and in their constant lack of avicularia and hyperstomial ooecia.
Callopora (Gray) Norman ', char, emend. Alderina Norman", Amphiblestrum Gray p. p., Ramphonotus Norman',
Doryj)orella Norman*. (1^1. IX, figs. :i^i).
The zocecia, which may have a varying number (0 — 1(5) of spines and a cryptocyst developed to a varying extent, are provided with a small number (5 — 6) of large few-pored pore-chambers. The owcia are hyperstomial. The ccto- ooecium, the calcified part of which often ends in a projecting margin, has a larger or smaller uncalcilied frontal portion. Dependent (wicnUiria generally appear, more seldom independent ones as well. The former may appear distally to the ooecium in an oblique position ami singly or in pairs, while in zocecia without ooecia they may appear singlj- and in different positions on Ihe proximal part of the zooecium.
Of species known to me 1 must to this genus refer Callopora lineata, (',. crali- cida, C. Diimerili, C. aiirita, Amphiblestrum Fleiniiuji, A. Irifoliitm. lidiiiphonoliis mina.v, Alderina imhellis and Doryporelhi spathnlifera. Despite the great variation in a series of structures all the above-mentioned species are so closely con- nected that it apj)ears to me to be necessary to refer them to the same genus. In all of them there is a small number of few-pored pore-chambers, and they all have hyperstomial ooecia \vith a partly uncalcified ectoooeciuni, which how- ever may be of very varying extent. The calcification of the ectoofrcium is least developed in C. Diimerili, in which species it appears only as a narrow mar-
83, p. 588. ' 83, J). 596. '■' 83, p. 597. * 84, p. 106
151
.^
f
ginal portion, and most developed in C. aurila (fig. 4 a). In C. ininax its extent is similar to that in (J. inibellis but is often indistinct, as it is not always sharply defined. In all of them there is a cryplocyst, the development of which is however not only different within the different species, but also varying ac- cording to locality and age of zooecia. Its development is slightest in C. craticnia and (L lineata, in which it is only a narrow marginal portion inside the spines, greater in C. Diinierili and C. aiiritd, and still greater in C. Flemingi, C. trifolium, C. imhellis and C. iniiKi.v. The last four species are evidently most closely allied. In the last-named species we find a strongly developed avicuhuiiim with an unusually high chamber (mounted on a pedicel-^ Norman'); but in this dille- rence I cannot find sufficient reason for setting up a new genus.
A later examination of some good colonies of Doryporella spnthiilifera has corro- borated my view as to the systematic position of this species which I must refer to the present genus. As I am later to give a full descrii)tion of this species in a work on the Ingolf Hiyozoa I may here just mention a few points of its structure. The so-called median pore is the aperture of an avicularium of the same form as those found in the distal part of the zooecium and corresponding to that found proximally to the aperture in C. Fleniinrii, C. minax and C. lineata, and in the last species there may also as in C. sjiathulifera be found a spine distally to the avicularium. There are 6 rosette-plates in the proximal half of the zooecium.
In old colonies of C. Flcminyi, C. minax and C. spathulifcra there may be found a compound operculum, the opercular valve and the membrane filling the rest of the aperture being fused together into a separable chitinous lamina.
Megapora Hincks.
The zooecia have a strongly developed, partially depressed cryptocyst and an aperture surrounded by spines and with a well-developed vestibular arch. A compound operculum in which the valvular part and the accessory part are connected by a joint. A few few-pored porC'Chambers. No auicularia. Hyper- stomial o<vvia whose ectooa'cium is calcified with the exception of a frontal triangular membranous part covering a corresponding very prominent granular part of the endoocEcium. The only species hitherto known are M. ringens, and M. hijalina Waters^. They are undoubtedly closely related to the Fleniiiigi-group within the genus Callopora.
' 83, p. 597. - lis, p. 39.
152
Tegella n. g.
Callopora Norman p. p.
(PI. IX., figs. 5-6).
The zocpcia, which have spines and a slightly developed cryplocyst, are pro- vided with multiporous rosette plates. Hyperstoniial mvcia with an infoinplelely calcified ectoooecium, which are again surrounded by m'inihiriit.
Of species known to me Callopora unicornis and C. Sophiae belong to this genus.
Foveolaria Busk, char, emend.
The entire surface of the zorrciuni is formed by a very thick, solid, much furrowed cryplocyst, which is deeply depressed in the whole periphery of the aperture. A very large, oval, compound operculum with a joint connecting the val- vular part and the accessory part. Multiporous rosette-plates. Hyperstoniial o(xria which are provided with a membranous ectoooecium and are finally hidden by covering calcareous layers. In most zocccia a large ai'icuhn'iiim proximally to the opening.
To this genus I can only refer F. elliptica Busk.
Caleschara Mac Gillivray', char, emend. Rosseliana Jullien.
There is no gymnocyst, but on the frontal wall of the zo(vcium a strongly developed, depressed cryptocyst, which is sometimes (C. denticulata) only perforated by a semi-circular opesia and two slit-like opesiula\ No spines. No avicularia. Endozooecial, but more or less distinctly prominent oivcia. All rosette-plates uni- porous.
This genus agrees with the majority of the Flnslriilae both in its possession of endozoa-cial oa^cia and uniporous rosette-plates. Of species described only C. denticulata M. Gill, and C. Rosseli And. belong to it. An undescribed s])ecies from Siam makes an intermediate form between the two just mentioned species, its cryptocyst terminating in a free, dentate lamina, and if we imagine this lamina coalesced distally with the dentate lateral parts of the cryptocyst, we should have two slits similar to those found in the former species. —
' 74, Vol. 2, Dec. V., p. 45, PI 48, ni<. 8.
153
Onychocella .luUien'.
Onychocellidae Jul lien.
(PI. XXII, figs. 3a-3(l, pi. XXIV, lig. 10).
The frontal calcification of the :oa>cia exclusively consists of a more or less developed, depressed cryptocyst. No spines. The operculum is sometimes a wholly chitinized simple operculuiji, sometimes a membranous opercular valve, and it is generally surrounded by an arch-like, chitinized thickening of the frontal mem- brane. The oblique, frontally ascending terminal walls are like the lateral walls two-layered, and both kinds of walls are provided with a lew mulliporous rosette- plates. The auicidaria are independent (vicarious), with a strongly developed cryptocyst and a flagellum-like, lengthened mandible which has a single or double, thin, wing-like expansion. The oa-cia, which may, I think, be considered endozooecial, appear as low, not strongly prominent, swellings from the proximal end of the distal zooecium, and they are separated on either side from the raised margin of the proximal zorecium by a suture.
This genus is plentifully represented in the chalk-period, while only a small number of recent species are known.
It will be noticed that the above diagnosis corresponds not only with the genus Onychocella Jullien, but with the bulk of his family Omjchocellidae, the latter comprising also a number of species, which must be referred to the new family Membranicelhiriidae set up by me. Although I have no doubt, that in time it will be necessary to acknowledge JuUien's family Onychocellidae, I shall at l)resent refer these forms to a single genus, as they are not yet so well known, that the genus can be divided in a natural way. Jullien has set up no less than eight genera, all of which however seem to me to be based on rather un- important differences.
Of this genus I have examined six recent species, among which one from Denmark Strait, O solida Nordg I. The latter possesses a simple, membranous oper- cular valve, while the others have a wholly chitinized, simple operculum, and this dillerence is in the examined species connected with another. The fact is that the free margin of the operculum is in all of them surrounded by an arched chitinous sclerite, but while in the five species this chitinous arch only reaches as far as the proximal corner of the operculum, it is in 0 solida Nordg. contin- ued a long way on the proximal side of the latter and here serves as base of attachment for a parietal muscle- With the exception of Onychocella Liiciae Jullien
' 42, p. 7. - 84 b, p. 8.
154
ooecia have hitherto not been made out with certainty, neither in fossil nor in recent species of this genus; but the reference of the above mentioned species to the genus Omjchocella does not seem to me to be unquestionable. The presence of avicularia with wing-shaped lateral expansions is not conclusive. I have found quite similar avicularia in a tropical Microporella s])ecies. With regard to the zon?cia themselves they seem to be more like tliose found in (killopora Flemingi and cognate species, as there seems to be a distinction between a strongly de- pressed cryptocysl surrounded by a projecting margin and an arched, jiroximal gymnocyst. The rather large ooecium issues from I he la Her and is in size, form and position unliUc the ooecia, which I have found in a series of recent and fossil species of the genus, and which are very little conspicuous, so little in fact, that they have hitherto been overlooked.
While all the other zoa?cia have a sharp and deep sutural funow in the whole of their periphery, which forms the l)oun(Jary between the projecting mar- gins of their own and those of the surrountling zorecia, such a sutural furrow is wanting in the distal end of the ooecium-bearing zoa'cia, and the proximal end of the distal zoa^cium does not as in the other zocrcia end in a low, rounded, projecting margin, but in a somewhat higher, more or less distinctly prominent swelling (the frontal wall of the oa'cium) which is but indistinctly marked ofT from the zoci'cium, and wliich seems to be covered by its frontal membrane. This slightly prominent, rounded pent-roof is on either side separated from the marginal cryptocyst of the proximal zoa-cium by a sutural furrow, hi the interior the frontally ascending distal wall touches the distal end of this swelling, and between the zocecial operculum and the margin of the occcium we find a slightly chitinized ocecial operculujn. Reference may be made to the schematic figure (PI. XXIV, fig. 10.), the dotted lines in which show how I picture the inner parts of this oa^ciuni.
Cupularia Lamouroux.
The zowcia broadU' rhombic, without frontal gymnocyst, but with a depressed cryptocyst perforated by a larger or smaller ajierlure. No spines. Each distal wall with one, and the distal half of each lateral wall with several (u]) to (i), scatte- red, uniporous rosette-plates. The lateral walls are common to the contiguous neighbouring zooecia. On the distal side of each zonecium we find an asymme- trical, independent vibraculnm with a long tlagelhim and an angularly bent, kid- ney- or bean-shaped opening. No owcia. The species hitherto described occur in free, discoidal colonies witli a thick basal surface covered by a membrane, the radiating furrows of which correspond with radiately arranged zocecial rows.
155
While all the other species have only an opercular valve, we find in C. Loivei Busk a wholly chitinized simple operculum, enclosed by a complete calcareous frame, the cryplocyst being raised proximally to the operculum to the level of the latter and forming its proximal boundary. This species might thus justly be referred to the family Microporidce. —
Lunularia Husk '. Lunulites Lamouroux, p. p.
The zntvcia (juadrangularly rounded, without frontal gymnocyst, but with a depressed cryplocyst perforated by a larger or smaller aperture. No spines. Each distal and each lateral wall with a number of scattered, uniporous rosette-plates. The lateral walls are common to the contiguous neighbouring zocrcia. The sym- metrical vibracula with a long flagellum and a deeply depressed, strongly develo- ped cryptocysl occur in shorter or longer rows or scattered among the zocrcia. No oivcia. The species hitherto described appear in free, discoid colonies with a thick basal wall covered by a membrane, the radiating furrows of which corre- spond with the more or less radiately arranged zocrcia. —
This genus, which is plentifully represented in the chalk-period, has only a few recent species. Of these I have had the opportunity of examining a fragment of /.. capiilm, kindly placed at my di.sposal by the British Museum.
II will perhaps be justifiable to combine the two genera defined above into one family Liimilariidae.
Selenaria Busk, char, emend. The zoa-zia rhombic or rhombicly hexagonal, without a frontal gymnocyst, but with a depressed cryptocyst perforated by a larger or smaller aperture. No spines. Scattered among the zooecia are a number of independent vibracula with an arched frontal surface perforated by numerous pores or by slits. A high ribbon- shaped lamina, issuing from the one lateral margin in the distal part of the vi- bracularian chamber stretches over towards the opposite margin and not far from this bends inwards towards the basal surface. It serves no doubt for the attachment of the flabellum. Distal wall with 2 multiporous rosette-plates, and the distal half of each lateral wall with a single one. Lateral walls are common to the contiguous neighbouring zoo'cia. The ocrcia, which seem to be endozooccial, appear on the surface of the colony as low, rounded, pent-roof-shaped swellings. The colonies are free, discoid, with a deepened basal surface perforated by numerous pores
' 8, p. 208,
156
and provided with radiating furrows, which correspond with llie radiafely arranged zott'cia.
Similar vibracula are found in the cretaceous species Rhagasostoma elegans V. Hag.
Family Cribrilinidae.
(I'l. IX, ligs. 9-11).
The zoa'cia with a larger or smaller, membranous i'ronlal area, covered by two rows of mutually coalesced, hollow, marginal spines, which form a frontal shield perforated by slits or pores.
The unnaluralness of this family may he sufficiently evident from the fact, that it is only based on a single character, which has moreover been taken from formations as variable and as inconstant in appearance as the spines. It is true that all such forms, in which the spines by their mutual connection form a shield broken through by slits or pores, have a certain outward similaritj', whicli without a close examination may easily be considered a proof of real relationship. The fact is however that we might be equally justitied in forming a family for all such Menibraniporidae, in which spines are absent or for such as possess two rows of well-developed, unconnected spines. In reality we do not in the other structural features find such a degree of conformity as might justly be expected in a natural family. A careful examination leaves no doubt of the independent origin of such a frontal shield in many difi'erent forms. That Ilarmer has a similar conception of these forms, is evident from the following statement of his: >The existence of great differences between the opercula of dilferent species at present referred to Cribrilina suggests that the genus is an unnatural one, representing a stage of evolution of the Lepralioid zooecium, which has been arrived at independently in several cases.- '
Electro monostachys (PI. IX, figs. 2 a — 2 b) and K. anyiilutu n. sj). (PI. XXII, fig. 4 a) constitute two of the best examples of the inconstancy of the spines. Here we may find in the same colony some zocrcia, which are entirely without spines, and others provided with a larger number of these structures. In the face of this fact it would surely be impossible to nuike the i)resence or absence of spines the only dislinction between two systematic sections. We are however able to mention two quite corresponding examples of the inconstancy of the frontal shield, viz, besides the above-mentioned Electra zostericola a new species from the Foeroes which is related both to Callopora Diimerili and to Menibrdiiiiiorella nilidu.
' 19, p. 329.
157
In this species we find within the same colony some zocecia, wliich are provided with a frontal shield similar to that in Membraniporella nitida, and some which have either only 2 — 4 short distal spines or besides these a varying number of longer, unconnected ones. A partial coalescence of s|)ines may also occur in several species. Thus, I find the first pair of spines coalesced in no small number of zod'cia on a colony of Membraniporiiui pijrula, Hincks from Victoria, and in the Meinbr. defensa described by Kirkpatrick a number of opposite spines (in the figured specimen 4 pair) may sometimes be connected. Such a coalescence of o[)posite spines also takes place in the whole length of the frontal area in Sto- lonella clausa Hincks, which belongs to the Bicellariidae, and a frontal shield formed by 5 coalescent broad spines occurs in Petalostegus hu-oriiis, which I have thought it most correct to refer to the same family.
The natural consequence of the view expressed above would then be the splitting up of the family Cribrilinidae and the grouping of its forms with such forms of the Membr(tniporidae. to which they are most closely allied. As however the latter family cannot be regarded as natural either, it must perhaps be broken up into a larger or smaller number of smaller families, and the forms, which have a frontal shield, must be divided among them. My material of both these families is however too small for me to venture upon making definite proposals for a final arrangement of all these forms, and therefore for the present I prefer to keep the two families unaltered. As the members of this family have their nearest relations in the family Membraniporidae. it is quite natural, that we should find' a similar extent of variation in most structures. The cryptocyst forms however an exception in this respect, as it is either completely wanting or appears only as an extremely faint margin within the spines (MembraniporelUt). This is a natu- ral consequence of the presence of the frontal shield, the latter making such pro- tection unnecessary as in uncovered Membraniporidae may be rendered by the cryptocyst. The frontal shield may be of very difVcrent extent, occupying at times the entire frontal surface and in other cases but a smaller part of the latter. It is much reduced in certain forms occurring in the Danish chalk-formation. While in some cases we find an opercular valve only, a wholly chitinized (simple or complex) operculum is often present as in the members of the family Scriipii- cellariidae, in which the opercular si)ine is so strongly develo|)ed that it forms part of the boundary of the operculum. As in Membraniporidae, the rosette-plates may be multiporous, uniporous (e. g. Membraniporella dislansj or there may be pore-chambers. The heterozooecia may appear both as independent and dependent ones, as avicularia and as vibracula, and rather frequently we find a calcified transverse bar between the opercular and the subopercular area. The ooecia are
158
hypersloiiiial or eiulozocrcial, and in the latter case they are surrounded hy keno- zoa'cia in the hitherto examined species.
Tlie authors, who have liitherto set up genera witliin this section, liave chiefly attached importance to the structure of the Iroutal shield, i. e. to the structure of and the connection between the spines, of which it is composed. Here again we must maintain, that on account of the vaiiable nature of the spines they are but badly suited to alVord generic characters, and we must call attention to the fact, that the difl'erent varieties, which Hincks lefers to (Irihriliiui iiunclaki, show such great dillerences in the structure of the frontal shield, that some of them cannot even be entered under his diagnosis of the genus Crihriliirci. I attach the greatest importance to the same structures that I have made use of in dividing the genera under Memhraniporidae. For want of material I must however here confine myself to give diagnoses of the following 5 genera.
Metnbraniporella Hincks, Char, emend. Lepralia (Johnston) Norman '.
The aperture in the frontal shield has an o[)ercular valve, and the shield is perforated by slits. There are pore-chambers with few pores, and the hyperstom- ial oa'cia are provided with an ectooti'cium but partially calcitied. Dependent ouiciilaria may occur.
This genus is here taken in a much more limited sense than by Hincks, and with the exception of the presence of the frontal shield the two species, that we have referred to it, correspond in ail characters with the genus Callopora and show signs of being specially closely allied to C. Uiiinerili. Tliis appears for one thing in the structure of the ooecia, the ectoooecium being in botli species only calcified in its marginal portion. A frontal shield appears constantly in M. nilitla, while tliis is not tlie case in an undescribed species from the Fa-roes. In the latter we find in tlie same colony, besides a smaller number of zoa>cia with a frontal shield, also some that are provided with but 2 — 4 distal, unconnected spines. This species thus forms a link between Callopora and Memhraniporella.
Cribrilina Gray. Cribrilina Jull. p. p., Gephyrotes Norman 84, p. 100.
(I'l. IX).
The aperture in the frontal shield, which encloses an opercular valve, is usu- ally provided with a more or less distinct proximal mucro. Pore-chambers with few pores. The owcia are hyperstomial or enclosed by kenozoa'cia, and the wholly
' 84, p. 100.
159
calcified ectoooeciuni is generally provided with a larger or smaller number of perforations. Dependent avicularia may appear, and the shield is perforated by pores.
Cr. pimcliUa, Cr. cryptoecium Norman ', Cr. aiinulatu and Geplnjroles nitido-
pnnctata (Smitl) belong to this genus.
In Cr. piinclata (fig. 11) we find in the same colony both hyperstomial ooecia and ocecia enclosed by kenozocrcia. On examining a longitudinal .section af Cr. annulata (fig. 10) we might be inclined to regard the ooecia as formed by a large distal spine. A closer examination will show distinctly, however, that the endoooecium is formed by the distal wall, which has 4 — 5 uniporous rosette- plates. Moreover the surrounding kenozou^cium (10 a) is provided with pore- chambers. As in the species of Retiflustra the basal i)art of the oa'cium lies higher (more distally) than its free, frontal margin (10 b).
Puellina Jullien", Char, emend.
Cribrilina JuU. p. p.
(PI. IX, fig. 12a).
The semi-circular aperture in the frontal shield is filled by a wholly chitini- zed, simple operculum. The shield is perforated by pores, of which those in its periphery serve as passage for short, tentaculiform evaginations from the frontal membrane, of which the first pair is considerably longer than the others. The ocecia, which are hyperstomial or enclosed by kenozonecia, have a wholly calcified ectoocecium. Few-pored pore-chambers. Independent but not dependent auiciilarid may appear.
Cribrilina radiatu, Cr. iimominata and Puellina Gattija' belong to this genus. The first-named species, which seems to have a wide distribution, will probably prove collective.
With regard to Harmer's contrary opinion^ of the structure of the frontal shield in P. radiala I can only say, that in this matter I share the opinion of Norman.*
Figulina Jullien ^, Char, emend. The aperture in the frontal shield, which has a more or less distinct sinus, is covered by a wholly chilinized compound operculum. Each distal wall with a row of uniporous, and each lateral wall with a number of mulliporous rosette- plates. Hyperstomial owcia whose ectoocecium is provided with a median suture
' 84, p. 102. -' 44, p. (i(>7. ■' 1!), p. li'ili. * 84, p. l)(i. '' 44, p. G08.
160
and with at least two pear-shaped perforations. Independent hut no dependent (wicnhiria may appeal'. The frontal shield with [)ores.
dr. figtilaris. Cr. pliiloinela i>. uniuda and Cr. clilhridiaUt ' belong to this genus.
M. pijriila is a Membraniporinu species which bears a close resemblance to Cribrilinu jigiilaris. I shall just mention thai the od'cia have also in this .species a median suture, and that the eclooo'cium appears to have a large, uncalcified region on eather side. It is however not so well delined as in Cr. /Kjiihiris.
Aspidelectra n. g.
Membranij)orella Hi neks.
The proximal part of the zoircium with 1 — 2, thick, projecting, hollow spines; the frontal shield perforated by slits; each distal wall with 2 multiporous rosette- plates, and the distal half of each lateral wall with a single one; the aperture in the frontal shield with an opercular valve; no ai'icuhiria; no o(vci(t.
A. melolontha, the only species hitherto known, must certainly be traced to Electra and appears to show specially close relationship to E. (tngiilata. with which species it agrees not only in possessing 1 — 2 jjrojecting spines, but also in having an angularly bent distal wall with a mulliporous rosetlc-[)late in each of the two basal corners.
Arachnopusia .luUien'-, char, emend.
The frontal shield, which has a small number of large holes and avicularia of varying size, is formed by the coalescence of a number of branched, originally hollow, later partially solid spines, which spring from the lateral walls. A mem- branous opercular valve. The angular distal wall has a number of uniporous rosette-plates while the rosette-plates of the lateral walls have 1—3 pores. Hyperstomial owcici with a wholly calcified ectoooeciuni and an ooecial cover formed by the adjoining frontal shields. The distal wall is in the ooecia-bearing zooecia continued frontally beyond the proximal part of the otrcium into a lamina terminating in a rounded, sometimes crenulated margin, from which a membranous ocecial operculum takes its origin.
To this genus belongs Crihrilina inonoceros M. Gill, which however comprises several rather different forms, that may possibly be considered independent s])e- cies. Cr. lerniinnhi M. Gill. '' may probably also be referred to Ibis genus. It has at anj' rate a prolongation ending in a crenulated margin similar to that found
' 108, p. 5. - 45, p. 62. ' 76, p. 5U.
161
in A. monoceros. It is in lliis s[)ecies seen al the bottom of tlie nperlure nearly on a level with the spines and separating the ooeciuni from the proximal zoce- ciiim.
As I cannot discover any relationship between Hianlopora ferox and Cribrilina monoceros, but find the peculiarities of the latter species sufficiently well-marked to make it represent a genus of its own, I shall keep Jullien's genus Aracli- iiopnsia, but on a new basis, and I think it may for the present l)e ranked under the above mentioned artificial family ('.lihriliiiidae.
2nd Division: Coilostega.
The frontal wall has within the covering-membrane a generally depressed, calcareous cover (the cryptocyst) surrounded by projecting margins, which either reaches the proximal margin of the operculum or is only separated from the latter by a small membranous portion. Spines of the usual form are usualh' wanting. The cryptocyst is as a rule provided with pores and most frequently with a foramen, the »opesiula« (sometimes confluent with the aperture) on each side, through wdiich a parietal muscle passes out to the covering membrane. These foramina may be either simple perforations of Ihc cryptocyst, or out- growths from their proximal and inner margin may sink into the zotrcium to join the basal (sometimes a lateral or the distal) wall in dilTerenl exlcntion. In most cases these »opesiular outgrowths*, as we may call them, form in connec- tion with the interjacent frontal wall and generally also with the basal wall a more or less complete tube, the »polypide tubes enclosing a part of the polypide. There is either a wholly chitinized, simple operculum or a partially strongly chitinized opercular valve. The avicuhiria or vibrncula are always independent. There may be hyperstomial, endozocrcial endofoichal or bivalvular oarin.
The families Microporidae, SteijanoporcUidae, Aspidostomidae, Tlialaiiioporellidae, Selosellidae, Chlidoniidae and Alijsidiidae belong to this division.
Family Microporidae.
The semi-circular aperture, which is bounded proximally by the distal, ascending margin of the cryptocyst, has generally a more or less strongly cliilinized (or calcareous), simple operculum, more seldom an opercular valve. Opesiulse, when present, are always distinct from the aperture. Pores may be |>rcsent or wanting and spines may appear. There may be (ivicnhiria, and the o(vcia, when present, are endozoa^cial or hyperstomial.
The family Microporidae is, in contrast to the following families, not quite natural, comprising as it does a series of genera which have independently
n
162
attained the correspondence in form of aperture and structure of ojierculum that we have just pointed out.
Micropora Gray. (PI. VIII).
The two opesiulse, which are more or less constant, have the form of simple perforations. Spines may appear. The oa'cia, which have a membranous ecto- ooecium, are endozoa^cial but very jjrominent, and the small aincuhiria, which are situated proximalh' to tlie aperture, are furnished with a complete cross- bar. Pore-chambers with few' pores.
To this genus belong M. voriacea Esper, M. perforata Mac Gill. (PI. VIII, fig. 4 a) and a species which has hitherto been confounded with M. coriacea, and for which I will propose the name M. Nonnani^ (PI. VIII, figs. 3 a — 3 b). Of this species I have only seen a little fragment from Hastings, sent me by the late Mr. Peal, and having lost it 1 shall only mention, that the operculum is calcareous and that the distal half of the endoooecium lacks that cryptocyst cover, ending in an angular margin, which is found in M. coriacea.
Microporina n. g.
The two opesiulse, which however are sometimes filled up, appear as simple perforations. Numerous pores. No oaxia, but avicularia with cross-bar occur. Each distal wall and the distal half of each lateral wall with a row (6 — 8) of one- or two-pored rosette-plates. A longitudinal series of parietal muscles is placed on each side between the cryptocyst and the covering membrane. Cellaria borenlis Busk and Micropora clomjala Hincks belong to this genus.
Macropora M. Gilliv., char, emend.
The zooecia verj' thick-walled, provided with pores but without spines and without opesiulse. The zooecial aperture is provided with a well-developed vesti- bular arch. Oo'cia and ordinary auiciilaria wanting, but among the zooecia we find some wliich have an aperture of a very different form and whose distal margin is furnished with three membranous, feeler-like filaments. Pore-chambers.
' 56, p. 7, note.
163
M. centralis Mac Gillivr.
A monograph of the tertiary Polyzoa of Victoria' Transact. Royal Soc. of Victoria,
Vol. IV, 1895, pag. 55, PI. VIII, fig. 3.
(1^1. VII, fif(s. 1 a— 1 (I).
The zooecia which are bounded by a rounded granular marginal ridge are large (length 1.3 mm.), broad, hexagonal, thick-walled, very strongly arched and within the brown covering membrane finely tuberculated and provided with small, scattered pores. The aperture, which is situated at a shorter or longer distance from the distal margin of the zod'cium, is surrounded by a thick, wall-like peristoni. It is large, almost semi-elliptical, but with the lateral margins somewhat con- verging proximally, where it is cut olT straight. Within this proximal margin we find in the whole breadth of the aperture a ridge-like, raised part supporting the operculum, and within the distal margin of the aperture there is a strong vestibular arch which is somewhat angularly bent from side to side. The two proximal corners of the extremely thick, calcified, tuberculated operculum, covered like the rest of the frontal surface by the covering-membrane (fig. 1 c), are se- parated by an extremely small sinuation from the remaining part of the proximal margin, and accordingly a very small slit appears on each side. In each of the proximal corners is seen a small triangular-rounded hinge-tooth. Each distal wall and the distal half of each lateral wall is provided with a long pore-chamber (fig. 1 d), with a row of uniporous rosette plates.
Avicularia of general structure are wanting on the fragment examined, on which however was found a zooecium with an aperture of peculiar structure fig. 1 b). It is more oblong than the others, and the two distally somewhat con- verging lateral margins meet in a distal margin, which has a median sinus. In this an almost black, short, feeler-like filament takes its origin from the covering membrane, and some way further down there is a similar^one issuing on each side. These filaments quite correspond with those discovered by Harnier in Piiel- lina radiata. The proximal margin of the aperture is furnished with a low, broad denticle.
Of this species I have had the oi)portunity of examining a small fragment from Wanganui, which inerusts a shell-fragment, and which was sent to me by Miss Jelly labelled »Mo;io/Jore/Za crassatiiui' , under which name I have mentioned it in ^Studies on Bryozoa« '). M. Claikei Tenison-Woods belongs to this genus, and in the figure Mac Gillivray" gives of this species we also see a zooecium
' 5G, p. 7. ' 7G, p. 55.
11*
1(U
with a peculiarly formed ai)crlurc, whereas neither the description nor the figures of M. centralis give any indication of the presence of such zooecia in that species.
Hemiseptella n. g.
From the proximal margin of the primary aperture a horizontal lamina taking up the whole hreadlh of the frontal wall, descends some way into the zod'cinm. The j)rimary aperture is more or less completely divided into a distal portion, containing an opercular valve with a strongly chitinized opercular arch and a proximal portion, represented by the two oi)esiuhe, the division being efl'ected either by the concrescense of two or three laminate processes or in a very incomplete way by three (two lateral and a median) group of s])inous pro- cesses. Small (iviculdi'ut. No i)ores and no spines. No (xrcia. The lateral walls are common to the contigimus zoo'cia. Large generally uncalcilied rosette-plates with several ('?) j)ores. Free branched colonies with pillar-like branches and strongly calcified zocecia.
To this genus belong Viiicnl(iri(i gntliica Busk* (= V. ste<i<in(tpiir<ndes Goldsl.), Vine, hibiata Busk and "Thalamoporelhi'^ Michaelseni Ca\\e[", in which last species the division between the opercular aperture and the two opcsiuhe is very in- complete, being only formed by three separate groups of spinous processes.
To judge from the figures, a number of the species, referred by d'Orbigny-', lo the genera Cellitvui. Quadricelhtria, Vincnlaria and Vincnlarind are no doubt related to this genus, and Vincnlnrid yotliicd"^ is at all events nearly related lo Hem. sleganoporoidcs Goldst. A similar form of aperture is found in Semicscliara himarfiinatd d'Orb.', and in Vincnlarind ohliqna^ d'Orb. the little avicularium has the same position as the avicularium in Hem. steganoporoides.
Having examined a piece of Heiii. steganoporoides and several pieces of Hem. labiatd, all from the Challenger Expedition I have come to the result, that the two forms are only local varieties, not distinct species, and firstly Hem. stegano- poroides in opposition to the contrary statement of Busk is furnished with a quite similar avicularium as is found in Hem. l(dnat<i. The chief difference however between the two forms is according to Busk to be found in the different origin of the central pier which separates the two opesiuhe, this j)ier being in Hem. steganoporoides formed as an ascending process from the proximal margin of the primary aperture, while in Hem. lahiahi it is formed as a descending process from the bridge, which is itself formed by a concrescense of two lateral pro- cesses. In a number of zoa'cia of Hem. l(dnata I have however found a more or
8, p. 72—73; 110, p. 13. ■' 11. p. 18. " SB. * 86, PI. 6o4. ■"' 80, I'l. 6(>0
165
less developed median laminate process springing from the proximal margin, while in others it is as in Hem. Micluielseni only represented by a group of spinous jirocesses. Also the form of the proximal margin of the definite aperture, which according to Busk in Hem. labiata is always strongly projecting (»the strong projection forwards of the oral bridge ) is subject to great variation, being sometimes straight, sometimes more or less deeply sinuated and sometimes pro- jecting. While the rosette-plates are as a rule membranaceous I have in the form .sleyanoporoides found a number of plates showing a greater or lesser degree of calcification.
Foraminella n. g.
The somewhat arched frontal wall lias no pores, but on each side a longi- tudinal series of (1 — 5) foramina (opesiulse). A membranous opercular valve. Independent aviciilarid without cross-bar, with an elongate mandible, on the one side furnished with a wing-like expansion. Hyperstomial oa'cia with a membran- ous ectoooecium. Pore-chambers.
The only representative of this genus is Monoporelht lepidn Hincks. As the name MonoporelUi must be kept for the first species, referred to this genus, M. noduUfera Hincks, which seems to be very diflerent from F. lepida, I have been obliged to set up a new genus for this species.
Calpensia JullienS char, emend.
The opesiular outgrowths join the lateral walls, forming a closed hollow on each side. A simple, feebly chitinized operculum. Numerous pores, but no spines. No occcia. No (ivicularia. The distal wall consist of a basal horizontal and a frontal ascending part, the former being furnished with a narrow transverse group of small uniporous rosette-plates. The distal half of each distal wall with a single multiporous plate.
This genus to which only a single species, viz. Micropora imprcfsa Moll can be referred, and which makes a transition to the following group Tuhifera, is nearly related to the genus Thalamoporella, from which however, it dilTers in the lack of spicules, oa^cia and avicularia. Besides, in no TImUimoporclUt, l)oth the opesiular outgrowths reach the lateral walls, and only in one or two species is found a simi)lc operculum with a straight proximal margin.
' 45, p. 78.
166
Group Tubifera.
Undt'i- the nbove name we may unite the three lollowing families, in wiiieli tlie deseendiiig ciyptocyst forms or lalves part in forming a shorter or longer, more or less complete, more or less insymmetrical tube, llie pnli/pidc lube, the frontal wall of which from a deeper level ascends towards the aperture. In all the members of this group a part of the cryptocyst descends more or less deeply into the zoceciiint, generally in such a way as lo join the basal wall with a shorter or longer basal edge on each side, i)ui in a few cases these oulgrowtlis from the cryptocyst only reach the basal wall {SIctjdnojKirclUi lladiloni, SI. liiislci) or the outgrowth on tlie one side only reaches the lateral wall (some Thalainoporella-species). While tiie frontal wall and the lateral walls of the polypide tube are always formed by the cryptocyst, the liasal wall is in most cases formed by the basal wall of the zoo'cium, and in such cases the outgrowths join this wall with a curved or angular edge on each side, the distally ascending parts of which indicate the form and direction of the tube (PI. V, fig. 5 b, PI. YI, fig. 5 d, PI. Via, figs, lb, 3e, 4 b etc.). More rarely the polypide tube has a basal wall of its own, the two outgrowths from the cryptocyst bending round and uniting within the basal wall of the zoa'cium, such forming a basal wall for the polypide tube. In that case tlie two outgrowths join the basal wall of the zoaxium in a continuous, curved or angular line and distally to this is seen the tube shining through the wall (PI. VI, figs. 3d, 7 i, PI. Vic, fig. If).
While in the Thalamoporellidae and in a few Steganoporella-specles (PI. V, fig. 3 a) the frontal wall of the polypide tube is distally on each side in con- nection with the lateral parts of the cryptocyst, this is not the case in the other members of the group, in which this frontal wall (the »median process^ Harmer in the Slcganoporellidae) is quite free. Thence follow^s, that in the TIkiIiuiio- j)orellidae the >opesiul3e« are completely separated from the aperture while in the other Tubifera they are fused together with it, bul this fusion can take place in difTercnt degrees, and while in most species of the genus Sle<i(moporclla and in the genus Aspidostoma the two opesialse are seen as two rounded sinuations from the aperture, they are completely melted together with it in .S7. bilcr<dis and in the genera Siphonoporelln, Labiopora and Cratcropom.
In all such forms, in which the basal wall of the polypide tube is formed by the basal wall of the zooecium, the opesiulse or the corresponding parts of the aperture leads into two cavities (the » lateral recesses* Harmer), more or le.ss completely sej)arated from the iioly])ide tube and from the remaining zocecial
167
cavity, but these two cavities are melted together in a single one in all these forms, in which the polypide tube has a basal wall of its own.
Synopsis of the families:
1) Zocecia with calcareous spicula in the shape of compasses and bows; ocecia with two calcareous layers, springing from the whole anter of the aperture; the opesiulaj are always completely separated from the aperture Thalamoporellidae n. f.
1) Zooecia without spicula; if ooecia are present they have only a single calcaieous layer (the endoocvclum) and are placed distally to the aperture of the zott'cium, which is distinctly visible:
2) No avicularia, no oo-cia, generally two forms of zoa>cia .. . Steganoporellidae. 2) Avicularia always and ooecia sometimes present; only a single
form of zooecia Aspidostomidae. '
Family Steganoporellidae.
The zooecia, which in most cases occur in double form, are always without spines, but generally provided with pores. The frontal wall of the polypide-tube is usually free, as the two opesiula; are generally not separated from the aperture of the zott'cium. The operculum, which is sometimes bounded by a chitinous sclerite proximallj', sometimes continued immediately into the frontal membrane, is as a rule very large and then suspended by strong hinge-teeth. Each distal wall with 2 and the distal half of each lateral wall with 1 — 3 multiporous ro- sette-plates. No avicularia. No owcia.
Synopsis of the genera.
The whole of the calcified part of tlie frontal area lying proximally to the aperture is a depressed cryptocyst; the aperture of the zowcium is surrounded distally and laterally by a projecting margin; the zoa-cia frequently occurring in two forms and provided with a large oi)er- culum armed with teeth, which is suspended bj' strong hinge-teeth; the polyjiide-tube is never continued proximally beneath the cryptocyst cover Steganoporella Smilt.
The proximal calcified part of the frontal wall is formed by a larger or smaller, arched gymnocyst; the aperture is not surrounded by a projecting margin; the zooecia occuiring only in single form
' This family has been put up by F. Canu (1 1 b, p. 276).
168
and provided wilh a small, always unariucd opercular valve; the polypide-tube is continued jjroximally beneath the cryptocyst cover Siphonopnrrllii Hincks.
Steganoporella Sniill.
I had already studied a series of StcudiioiKirclhi s|)ecies and prepared the figures given on PI. V, when I received Harmer's excellent monography of this genus. Accordingly 1 shall here only make a number of observations on the structure of this genus, especially with regard to llie species examined by nie.
While the operculum is in most species surrounded distally and laterally by a projecting margin formed by the gymnocyst, the whole of the remaining calci- fied frontal wall is a cryptocyst, as the covering-meml)rane starts from the narrow frontal edges of the lateral walls. Besides the polypide-lubc the cryptocyst shows a distinction between a depressed central portion wilh pores and a raised, more or less strongly tuberculous nuuginal portion without pores, which may l)e less distinct in the proximal part of the zooecium. In some species, e. g. in S. laleralis (PI. V, figs. 7 a— 7 d) we also find such a raised, non-porous, tuberculous portion immediately on the proximal side of the aperture of the zocrcium and the polypide-tube. In most species the lateral, raised marginal portion of the crypto- cyst is continued distally between the hinge-teeth and forms an arched trans- verse ridge, the »oral shell's across the distal wall proximally to the distal margin of the opening. This distal cryptocyst, which springs from the angle between the basal, more horizontal and the frontal, more ascending part of the distal wall, is slightly developed in S. neozdanica (fig. .3 a) and quite absent in >S. neozelaiuai, V. magmficn (fig. 4 a) and in .S. lateralis (figs. 7 a, 7 b). While in all the other species the »opesiular outgrowths* terminate on the basal wall, they end in 5. haddoni Harmer and .S. Buski Harmer (figs. 6 a— 6 c) on the distal wall, which accordingly in both these species forms the basal wall of the polypide-tube. The way in which these outgrowths join the l)asal wall in the species examined by me or, what comes to the same thing, the way in which the basal wall of the polypide-tube is formed, seems however lo be subject to rather great variation within the same species or even within the same colony. This is easily seen through the basal surface of the colony, the lines in which the outgrowths join the latter being visible. In St. magnilabris as well as in St. lateralis Harmer the basal wall of the polypide-tube may sometimes be formed by the basal surface of the zocrcium, which is the case in the two upper zoa-cia in fig. 7 d, but some- times the polypide-tube has a basal wall of its own, which is seen in the 1 lower zooecia in the same figure. In the piece of St. macjnilabris represented in fig. 5 b
160
the [)olypide-tube is in most zooecia formed by tlie basal surface of the latter: but in this species it is as common to fin<l poly[)ide-tubes with an independent basal wall. P^xcept in S. lateralis, the cylindrical polypide-tui)e of which has only a more or less strongly outwards bent distal margin (figs. 7 a — 7 c), the qua- drangular or trapeziform frontal wall of the polypide-tube is in the other species provided with more or less protruding, frontal ly directed marginal flanges. In ,S. neozekinica (ligs. 3 a, 3 d) and S. neozelaiuca, var. nmiimfwa (figs. 4 a, 4 c) these form a long and, especially in the former very narrow tube, which is closed internally by the frontal wall of the polypide-tube. The bottom of this tube is provided with pores which may also appear on the adjoining parts of the opes- iular ingrowths.
Siphonoporella delicatissima Husk. Membranipora delicatissima BusU, Quart. Journal micr. Sci., n. ser.. Vol. I,
ISfil, pag. 153, PI. XXXIV, fig. 1.
Siphonoporella delicatissima Harmer, (juart. .lourn. luicr. Sci., n. ser., Vol. 43,
1900, pag. 231, PI. 13, figs. 42, 43.
(PI. VI, fif^s. 3a-3il).
The zoa'cin narrow, rectangular or longitudinally hexagonal. Willi the excep- tion of the arched, sometimes coarsely transversely striated gymnocyst developed in the proximal part of the zooecium, which in its middle measures one-fifth at most of the whole length of the zooecium, the frontal surface is otherwise mem- i)ranous. The finely granular concave cryptocyst, which joins the gymnocyst in a semi-elliptical boundary line, sinks distally in the shape of a pent-roof towards the basal surface, which it reaches in a continuous line formed by two une- (jually large curves, which meet at an acute angle (fig. 3 d). The polypide-tube is situated closer to one lateral wall, while at the same time it inclines towards the ojjposite one. It is a rather long, cylindrical tube which generally increases in width distally and terminates in a somewhat expanded margin provided with a number of finer and coarser teeth, of which some may be rather long and pointed, sometimes branched. The surface of the polypide-tube may also be more or less nodulous, and these nodules may soiuetimes be annularly disposed. We may designate the side of the polypide-tube nearest the one lateral margin of the zooecium as the inner and the other as the outer side. The freely projecting part of the polypide-tube just described is continued proximally under the pent- roof-shaped cryptocy.st cover, and this proximal part, which is oblicjuely truncated at the end (fig. 3 c), is clearly visible through the cryptocyst. The boundary be- tween the distally and proximally directed part of the polypide-tube is formed
170
by a line, which passes ohli(|ueiy proxiinally from the outer corner lo Ihe oppo- site lateral margin almost parallel with the proximal truncated part of the poly- pide-tiibe. The part of the basal surface of the polypide-lube, which lies distally to the just mentioned angularly bent line, has an independent wall, while the basal wall in the proximally directed part is exclusively or mostly formed by the basal wall of Ihe zocrcium. The obliquely ascending distal wall has within its basal margin a multiporous rosette-plate on each side, and a similar plate is found in the distal half of each lateral wall. In Ihe apjiroximate centre of the distal margin of the cryptocyst a larger or smaller tubercle rises, from which five yellow, proximally connected bands take their origin. They appear to be fastened to the covering-membrane, and the same thing seems lo be the case with a similar number of bands, which spring from the outer lateral wall. These bands are undoubtedly parietal muscles. Each of the margins of the colony shows a series of narrow kenozooecia which have a wholly membranous frontal cover and no cryptocyst.
Besides a small fragment liom King George's Sound, West Australia, for which my thanks are due to the late Mr. Feal, I have examined a number of colonies from Australia, found in the herbarium of alga^ in the Hotanical Museum. The species has hitherto lieen found only on Anuinsid pinnaiifuln.
Siphonoporella nodosa Hincks. Annals Nat. Hisl. ser. 5, Vol. 6, pag. 90, PI. XI. fig. 10. (in. VI, fif^s. 2 a, 21)). As I have only been able to examine a small fragment of this s|)ecies (from Australia), which I lost before I had completed my examination, I shall here only make some comparative and supplementary observations. As in Ihe |)re- ceding species we find here a proximal, but much stronger developed gymnocyst, a pent-roof-shaped cryptocyst and a |)olypidc-tube, which is continued proxi- mally under the cryptocyst roof. The dislnl part of the |)olypide-tul)e is however very short, and the whole of its basal wall is formed exclusively or nioslly by the basal wall of the zooecium. The distal wall is niso here somewhat ascending and provided with two multiporous rosette-plates. The dist;d half of each lateral wall with 1 —2 similar plates.
Family Aspidostomidae.
The zocvcia, in which a raised margin is often indistinctly or incompletely developed, are always without spines and have generally a strongly developed distal end, sometimes projecting in the shape of a pent-roof. The two opesiulaj
171
appear as narrow incisions, which join the zocecial aperture, and the short po- lypide-tube, which is not continued under the cryptocyst cover, is in most cases [)rovided with marginal ilanges. Aoiculaiia are always present and sometimes hyi)ersloniiai ocrcia, on each side of which we generally see a compressed, higher or lower process. The distal wail as well as the lateral walls may have some- limes uniporous, sometimes multiporous rosette plates.
Synopsis of the genera.
1) 0(L'cia occur, on each side of which a compressed process is generally seen; no distinct raised margins; frontal wall of polypide- tube quadrangular or trapeziform, surrounded by more or less strongly projecting Ilanges Aspidostoma Hincks.
1) No oo'cia; distinct raised margins; frontal wall of polypide- tuhe not quadrangular and not surrounded by projecting flanges:
2) Polypide-tube bilabiate, on either side connected with the lateral wall by a vertical calcareous lamina; multiporous rosette- plates Ldbiopora n. g.
2) I'olypide-tube not bilabiate, with an expanded distal margin, not connected with the lateral walls by vertical calcareous laminae; uniporous rosette-plates ■ ■ ■ CrateropoVa n. g.
Aspidostoma giganteum Busk. — f^/ft Vf_C . A?J $A-2f Eschara giganlea Husk, Catalogue of Marine Polyzoa, Part I, Cheilostomata,
pag. 91, PI. CXIX, fig. 3. Aspidostoma crassum Hincks, Annals Nat. Hist. ser. 5, Vol. 7, pag. 160, PI. X,
figs. 6, 6 a. Aspidostoma giganteum Busk, Challenger Zoology, Vol. V, Part I, pag. 161,
PI. XXXIII, fig. 3. — — Jullien, Bryozoaires, Mission du Cap Horn, pag. 77,
PI. 6, figs. 5—6. Aspidostoma gigantea Waters, Challenger Zoology, Vol. XXXI, pag. 28, PI. 1,
figs. 16—18, PI. Ill, figs. 20, 21. Micropora cavata Waters, Quart. Journ. Geol. Soc, Vol. XXXIX, pag. 435.
(PI. VI c, figs. 2 a-2 d). The zooecia, which may attain a length of up to 1.5 mm., are typically hexagonally lyre-shai)ed, but often of a rather irregular form. They are very thick- walled, almost without pores and provided with a close reticulation of small tuberculated ridges. They attain their greatest height in the strongly projecting
172
and boldly arched distal cnil, Uk' free margin of which gencralh' tcrminales in two broad processes separated by a narrow incision and forming with eaeh other an angle of W (figs. 2 a, 2 c). On the proximal side of the aperture and of the polypide-tube we find the central [lorlion of the frontal surface provided with a more or less deep depression of somewhat dilTeienl extent; l)nt the greater part of the frontal surface of the zoo'cium is always arched. \n the middle of the depression there is generally an oblong thickening which reaches the polypide- tube with its distal end. The polypide-tube may sometimes be so completely covered by the arched distal end of the zonecium that it is difficult to discern its frontal part, which is surrounded by strongly projecting, frontally directed tlanges and has the form of a rectangle, the two sides of which are carved in- wards a little. It is separated on either side l)y a long, oval incision — the two opesiulae — from the lateral margins of the zooecial aperture, and its lateral walls seem to reach the basal wall (fig. 2 d). Tlae well chitinized and very low oper- culum ') has a somewhat convex proximal margin corresponding (as in the genus Steganoporella) to the distal margin of the polypide-tube and besides, it is furn- ished at each proximal corner with a prolongation fitting into the o])csiular sinus. The distal wall as well as the lateral walls are provided with a row of 6 — 8 small, uncalcified, most probably uniporous rosette-plates.
The ooecia (fig. 2 a), of which a few specimens were found on the examined fragment, are strongly arched, longer than broad, and they have a honeycombed surface. They are enclosed between two long vertical swellings, which are con- tinued proximally to the ocrcium into two parallel [)rocesses that grade into the arched lateral i)arts of the frontal wall. Between these processes and the free margin of the ooecium we find a ([uadrangular opening forming something like a vestibule to the zoo-cial aperture. The oo'cia spring from the surface of a similar, distal prominent [)art as is found in tlie other zooccia, but it is flatter, and the two swellings, which enclose the ooecium between them, might corre- spond with the two processes from the free margin of the distal end, occurring in the greater part of the other zooecia. The ocecia have but a rather small opening.
The avicularia, which are scattered among the zonecia but in much smaller numbers than the latter, are small, of a triangular outline and provided with an opening, which has almost the form of the figure eight.
The colonies form free, two-layered expansions.
Of this species 1 have examined a dry coloni from the Antarctic Ocean. To
' no. |). 29, |)l. Ill, fig. 21.
173
judge from the various quoted descriptions and figures the species seems to be subject to considerable variation, or it may possibly be divided into several. In the form figured by Waters the ooecia are very low, and the processes issuing from the free margin of the distal end arc sometimes digitately lobcd. This may also be the case with the i)ostooecial processes, which may appear as very pro- jecting, Hal spines.
To the genus Aspidostoina I may provisionally refer the following three species from the French cretaceous formation: Kschara Aegon d'Orb. (PI. VI, fig. 3 a), E. Anliopa d'Orb. (Pi. Vic, fig. 4a) and E. AInlnntha d'Orb. (PI. Vic, fig. 5a). In all three of them we find in the proximal part of the ai)erture a region sur- rounded by protruding margins, similar to that found in A. giganteiim, and which may be the frontal wall of a similar polypide-tube. I have however not yet been able to satisfy myself as to whether it sends prolongations to the basal wall. There are other points of similarity, as the partially arched surface of the zooecia, the more or less, projecting distal end, and in E. Aegon and E. Antinpa the pre- .sence of postoo^cial processes. While these in E. Antiopa only lake j)art in the delimitation of the large vestibule, they arc in E. Aegon as well as in the just- mentioned form of A. giganteiim freely projecting in the shape of fiat, almost rib-like processes, which however have here coalesced into a flat, arched band, separated from the free margin of the ocecium by a transverse slit. In the above- mentioned three species there seems to have been no great number of small rosette-plates, as each distal wall shows one and each lateral wall two trans- versely oval openings, which may originate from as many nuiltiporous rosette- plates.
I may here add that Canu in two valuable works' on tertiary Brijozod has referred 4 new species to the genus Aspidostoina.
Crateropora falcata n sp.
(PI. VI, lii^. 1 a). The zooecia, which may attain a length af 1 mm, are generally hexagonally rounded or ligulale, but have sometimes a rather irregular form. With the excep- tion of the proximal margin and a shorter or longer part of the adjoining lateral margins Ihey are surrounded by a raised granular border, which increases in height dislally and ends in i curved, strongly protruding distal portion, within the proximal margin of which is seen a low ridge parallel to its free edge of the zoa-cium. The depressed, very tuberculous cryptocyst is provided with small.
' 11 a, p, 13—14. lib. p. 278—279.
174
scaltered pores. It sinks f^nuUially towards the distal end and rises on either side of the poiypide-tube under an obtuse angle into a steeply ascending, narrow portion, which forms the lateral margins of the aperture and lades away at the distal end.
The polypide-lube tills the entire width of the large, almost semi-circular aperture. It is short, of semicircular transverse section and provided with a collar-shaped outwards curved margin. As the opesiular outgrowths reach but half-way down on each lateral wall, the basal wall of the polypide-tube is formed only by the basal wall of the zooecium.
Each distal wall which is strongly curved from side to side, and the distal half of each lateral wall have a row of small, uniporous rosette-plates.
Ooecia are not found.
Avicularia. On the small fragment only a single, small, Irapeziform, falcate avicularium was found, the large, depressed cryptocyst of which is |)erl'oratcd by a small, oval opening. In the proximal end of this we see a small, triangu- lar process, which shows traces of having originated by a concrescence of two lateral halves. On the whole this avicularium bears a close resemblance to that found in »Eschara« Antiopa, d'Orb. (PI. Vic, fig. 4a).
A small piece of this species was found on a dry TiuUtcmi, locality not noted. In the structure of the zoa?cia this species shows some resemblance to Steganoporella patiila Mac Gillivr. S at any rate as they are represented in fig. 20. The avicularia have however another form, and this species is moreover said to be provided with oa>cia occupying the place of a zocccium. What the author calls an ooecium might, I think, more correctly be called a deformed zocEciuni without aperture.
Labiopora crenulata n. sp.
(in. YI, fig. 4:.).
The zooecia rectangular or longitudinally hexagonal, surrounded by a rather wide, but not strongly projecting, crenulated and transversely striated cryptocyst margin. The depressed part of the cryptocyst, which is somewhat luberculaled and with the exception of the part near the i)oIypide-tube provided with nume- rous, rather large pores, reaches with its opesiular outgrowths the basal wall, which it meets in a continuous, straight, transverse line on the boundary of the distal fourth of the latter. The polypi<ie tube, whose transverse section is roun- ded, has an independent basal wall and is distinctly bilabiate with a more pro-
' 76, p. .54.
175
jecting basal lip, the free margin of which is strongly rounded, very often angu- larly curved, the frontal margin being more or less distinctly concave or sinuated. It is on either side connected with the lateral wall of the zooecium by a vertical calcareous lamina. The distal wall, which is composed of a basal, horizontal and a frontal, obliquely ascending part, is on either side provided with a multiporous rosetle-plate, and a similar plate is also found in the distal half of each lateral wall.
Ooecia wanting.
The avicularia, scattered in rather large numbers among the zooecia, are a little larger than tJie latter but otherwise of similar form. The strongly developed cryptocyst has in its centre a quadrangularly oval opening with crenulated mar- gins, and in the frontal third of this there is on either side a hinge-tooth. The cryptocyst is most depressed in the distal half of the broad, distally rounded, opercular area, which no doubt corresponds to the mandible. On the proximal side of the opening the cryptocyst is less depressed and surrounded by an indi- stinctly bounded, crenulated, marginal portion. There are a few pores in the proximal part.
Some colonies of this species occurred on the same specimen of Tridacna sp., on which I found Crateropora falcata.
. Family Thalamoporellidae n. f. (I^ls. VI, Via, VIb, YIt).
The zoivcia, which always occur in single form, have pores, free calcareous spicules in the shape of compasses or curves and very often two adoral, acropeta- lous spines, as a rule very short and wide. The membranous or very feebly chi- tinized operculum (or opercular valve) is more or less completely separated from the covering membrane by a single (PI. VI, fig. 6 h, pi. VI a, figs. 3 a, 3 b, 4 c, pi. VI b, fig. 5 b) or double (Pi. VI, fig. 5 a, pi. VI b, fig. 3 a, 6 a) chitinous scle- rite, on each side in connection with the opercular arch. The proximal border of the operculum is generally concave, more rarely straight, and in the first case does not fill up the entire aperture, which in most species is provided with a broad sinus. The two opesiulae are separated from the aperture of the zooecium, and consequently the frontal wall of the polypide-tube is not free. The distal wall, consisting of a basal, more horizontal and a frontal, more ascending part, has within its basal margin a crescentic collection of small, uniporous rosette- plates (rarely replaced by one or two multiporous), while the distal half of each lateral wall has a single (rarely two) multiporous plate. Avicularia occur and large very prominent hyperstomial ocvcia, which arise from the whole periphery
176
of the anler. Their calcified ectooau-ium is generally devoid of pores, and their aperture is closed by a horizontal ciij)-sha])ed chitini/ed operciiluni which is connected at its base with the opercuhiin of the gonozooecium.
The zooecia are usually rectangular, and the aperture has a somewhat raised anter and generally a more or less broadly rounded sinus between the two more or less distinct hinge-tcclh. Immediately on the distal side of these is a more or less distinct line, (most clearly visible on PI. VI b, figs. 2 a, 8 a i.<: 6 a) which curves outwards and is continued into the line forming the boundary between the narrow marginal edge and the cryplocyst. In 77i. expansd (PI. VI b figs, f) a — 5 e) and VVi. mdinilluris (PI. Via, figs. 5 a — 5 e) the aperture has contrary to the rule a proximal margin which is straight or almost straight, and in VVi. Rozieri, var. Idhidld (PI. VI, figs. 6 a — Oj) the sinus is filled more or less completely by a lip-shaped process, (figs. 6 f , (> g). The line mentioned above, which curves outwards on the distal side of the binge-tooth, forms the boundary between the cryptocyst and the gymnocyst, the latter occupying the region on the distal side of this line. While the aperture in some cases e. g. in 77i. luuHte liollandiae (PI. VI a, figs. 3 a — 3 f) takes up the whole or almost the whole of the breadth of the zoa'cium distally, so that the gymnocyst is exclusively or mostly represented by the anter of the aperture, it is in most cases j)re.sent on either side af the aperture as an area developed to a varying extent and in diflerent ways, which we may term the adoral area-. This is sometimes developed in the form of a level or slightly arched surface, obliquely ascending towards the distal margin, or sometimes the whole or part of its surface is taken up by an acropetalous spine, most often short and wide with a broadly rounded terminal part, (PI. Via, figs. 4 a, 5 a) seldom more like an ordinary spine (PI. VI b, figs, lb, 1 c, 2 a). The calcification of these spines takes place in a number of narrow longi- tudinal belts, and accordingly their surface is radially striated more or less sharply, and the growing spine also ends in a crenulated margin. The development of the adoral area is however subject to great variation within the species, and it may even l)e different on the two sides of the same zooecium.
The cryptocyst, which forms the whole of the remaining calcified part of the frontal wall of the zooecium within the raised margins of the lateral walls has as in the species of Ste(janoporeUd a more or less developed crenulated marginal part, and apart from the outgrowths from the two opesiuhe it has its greatest depth at the proximal end of the polypide-tube, that is to .say, in a line carried through the |)roximal margin of the two opesiula;. This Wuv, which lies some- what proximally to the centre of the zocrcium, forms the approximate distal limit for the appearance of pores. The two opesiuhe, which enclose between
Ihem the frontal wall of the polypide-tube ascending towards the aperline and which, contrary to the case in the Axjniloslomidae and the majority of the Ste- ganoporellidae, are always separated from tlie a])erture, never seem to be developed ([uite alike, although the difference Ijetween them may be greater or smaller in the different species. To begin with, there is always a difference in size, and further the smaller of them generally sinks more or less obliquely towards the corresponding lateral wall, so that it either does not reach the basal wall at all, or only touches the latter to a smaller extent than the larger, the direction of which is more vertical to the base, hi Th. inainilhtris (PI. VI a, figs. 5 a — 5 e) only one opesiula appears to be present. The two lateral recesses, formed by the opesiular outgrowths, may in the different species be more or less completely separated from the polypide-tube and the zoa'cial cavity, and in the case of Til. Kozieri, var. labutta (PI. VI, figs. 6 a — 6 j) as well as in Tli. novae holUmdiae (PI. VI a, figs. 3 a — 3 f) they form two almost completely closed spaces, which however have a small foramen in their distal wall just within the distal margin of the opesiula. While in these two forms the outgrowths join the basal wall in a closed curved line springing from the lateral margin, the corresponding curved lines in the other forms lack a greater or smaller part of the distal boundary, as not only the distal wall of these lateral recesses, but also a greater or smaller part of the lateral wall of the polypide-tube is absent (PI. Via, fig. 4 b, PI. VI b, figs. 1 e, 5 e, 6 b). These lateral recesses are most reduced in 77). Rozieri var. (•(difornica (PI. VI b, fig. 2 d). A rare case in the genus TludamoporeUa is found in Th. lioticha (PI. VI, fig. 7 i) and in some zoa'cia of Th. Harmeri (PI. Vic, fig. 1 f), the outgrowths in which, in the same way as in certain forms of Stegano- porella, meet the basal wall in a continuous line, which takes up the entire bre- adth of the wall, while the polypide-tube has at the same time a basal wall of its own, and on the whole these opesiulie, in spite of the great variation they show, may atlord good specific characters.
The structure of the distal wall is similar to that in Stegaimporella, being composed of a horizontal or slightly ascending basal part and a steeply ascending short frontal part. As in the species Sleinmoporella a more or less well developed oral shelf springs from their junction.
The very peculiar calcareous spicules occurring in all the species of this genus are situated partly in the cavity itself of the zooecium, where the largest are always found, partly in the space between the cryptocyst and the covering mem- brane. They are found both in the avicularia and in the ooecia, and despite the great variation they are subject to, they generally afford good specific characters. The avicularia, which are as a rule smallei- than the zooecia, though they may
12
178
attain the size of the laller, have most often a strongly developed distal ciypto- cj'st, and outside the opercular arch the mandible has in most cases wider or narrower, marginal expansions. The avicularia also generally olTer good specific characters. With regard to the structure of the gonozooecia and the ocrcia re- ference may be made to the separate species.
A single genus Thalamoporella. Synopsis of the species.
1) Spicules Ijoth in the form of curves and compasses.
2) The opesiular outgrowths generally meet the basal wall in a continuous, transverse line, which lakes up the entire breadth of the wall; (the operculum without continuous proximal chitinous sclerite; the avicularian mandible vase-shaped; curves very slender; the largest
not much shorter than the longest comjiasses) T. lioliclui Orlmann.
2) The ojjesiular outgrowths never meet the basal wall in a conti- nuous line, which takes up the whole of its breadth; (the basal wall of the polj'pide-tube formed by the basal wall of the zocecium):
3) The two legs of the compasses are different, one being curved inwards and iiooked at the end; (the operculum with continuous proxi- mal chitinous sclerite; the surface of the zoa'cia divided into 3 — 4
areas, separated by sutures) T. Jerooisi Hincks.
3) The legs of the compasses are not different.
4) The avicularian mandible has the form of an isosceles triangle with somewhat convex sides. Of the two opesiular outgrowths generally only one reaches the basal wall; (the operculum of older zooecia with continuous proximal chitinous sclerite, or the latter is only broken for
a short distance) T. Rozieri Aud.
4) The avicularian mandible is never triangular, but more or less re- gularly tongue-shaped or vase-like; the two opesiular outgrowths both reach to the basal wall, which they never meet in closed curved lines; (the proximal margin of the operculum on each side with a short chitinous sclerite) T. (iniunlalit n. sp.
1) Only compass-like spicules occur;
5) The proximal margin of the zorecial aperture is straight or almost straight;
6) Only a single opesiular outgrowth reaching to the basal wall; the proximal margin of the opesiula is generally furnished with a row of partially furcate spine-like processes, and similar processes may ap-
179
pear on the other lateral half; the proximal margin of the operculum somewhat concave; the avicularian mandible triangular with linear terminal [)art '/'• niamillaris Lamx.
6) Two opesiulffi of about the same size, both reaching the basal wall; no spine-like processes; the zocecial aperture with a large discoi- dal expansion distallj', and the operculum, furnished with a correspon- ding expansion, has a proximal straight margin; the avicularian man- dible semielliptical with triangular opercular arch T. expansa n. sp.
5) The proximal margin of the zocecial with a broad and deep sinus:
7) Proximally to the opesiulse each lateral margin is prolonged into a sharply projecting, thick-walled, semicircular or rounded triangular process, inclining towards the cryptocysl; (the proximal margin of the operculum with a continuous chitinous sclerite; the avicularian mandible triangular, only one opesiular outgrowth reaches the basal
wall) T. cincta Hutton.
7) No such processes:
8) The opesiular outgrowths, of which in most (or all) zocecia only one reaches the basal wall, meet the named wall in closed curved lines; (the avicularian mandible broad, quadrangularly rounded, in the proximal part narrowed; the smallest compasses with almost rectangular opening) T. novae hollandiae Hasw.
8) Both opesiular outgrowths reach the basal wall, on which they form no closed curved lines:
9) A short chitinous sclerite on either side of the proximal margin of the operculum, the lateral margins of which are parallel; the avi- cularian mandible narrow, claw-shaped, bent to one side . . 7'. falcifera Hincks.
9) The proximal margin of the operculum with a continuous chiti- nous sclerite and with lateral margins convergent distally; the avicu- larian mandible has the form of an isosceles triangle; (on the basal surface the two opesiular outgrowths may form sometimes two separate lines, of which one is hook-shaped, sometimes a single continuous, often trapeze-shaped, transverse line; ooccia with pores) T. Uarmeri n. sp.
Thalamoporella lioticha (Ortmann). Micropora lioticha Ortmann Archiv f. Naturgesch. 56 Jahrg, 1, 1890, pag. 30,
Taf. II, Fig. 11a— b. (V\. VI, figs. 7a-7p, PI. VI b, fig. 4 a). The ztHL-cia, the length of which is between 0,79 and 0,99'""', have only slightly developed, indistinctly marked and sometimes quite reduced adoral areas,
VI*
180
always without acropetal spines. A well — developed oral shell'. The aperture, measuring ahout one-fourth of the entire length of the zocecium has a hroad and deep, rounded sinus, the cui\e(l line of wliicli would sometimes meet the rest of the margin in a circle, if it was not separated from the latter hy the well-deve- loped hinge-teeth. The proximal part of the operculum is on either side furn- ished with a short chitinous sclerite. The cryplocyst, which has rather small, widely scattered pores and small dispersed tubercles, has a distinctly projecting marginal i)orlion, without distinct crenulation. Of the two o[)esiul£e the larger is at least twice the breadth of the other and formed like a long rounded trape- zium. The opesiuiar outgrowths both reach the basal wall, which they gene- rally meet in a continuous transverse line, occupying the entire bieadth of the wall (tig. 7 i). The unusually narrow poIy|)ide-tuI)e has an almost smooth and [)roximally much depressed frontal wall, and contrary to the common rule in this genus it has a basal wall of its own, which is liowever in the majority of the zoa^cia very short, sometimes almost imperceptible, and at most attains half the length of the entire polypide-tube. Otherwise tiie poly[)ide-tube is only re[)resented by its frontal wall.
The spicules (fig. 7 c), which only seem to be present in the zocrcial cavity, occur both in the shape of curves and of comi)asses. The length of the latter may vary between 0,099 and 0,305'""' and the curves, which are unusually thin with sharply bent ends, measure from 0,039 to 0,179™™- The dimensions of both forms are a little different in the variety with |)rismatic branches.
The ooecia have, when seen from the front, a broad, obcordate outline, and a horizontal, rounded triangular, aperture whose somewhat protruding lateral margins meet into a roof-sha|)ed ridge continued some way along the uuddle of the ooecium, thus giving the whole of this portion a sagittal outline. The short gonozooecia have two opesiulse of about the same size and a semi-oviform ope- ning with a comparatively narrow sinus. Their membranous operculum has a little within the margin a narrow continuous chitinous arch. The gonozooecia occur in continuous rows, separated by twos by a row of ordinary zooecia.
The avicularia, which may attain a length similar to that of the zoa>cia, while their breadth is considerably smaller, have a vase-shaped mandible, the opercular arch of which has the form of an isosceles triangle with the legs meeting a little inside the point. The shape of the posl-opercular opening of the cryptocyst may vary a good deal, being sometimes rounded ([uadrangular and sometimes forming part of an oval. On the other hand the proxinud margin of the well-develoi)ed distal cryptocyst always forms part of an oval.
The colonies may occur both incrusting and free, in the latter stale some-
181
limes as broader or narrower two-layered laminae, sometimes branched with prismatic branches.
Besides some fragments of broader and narrower, two-layered colonies from Wladivostock-Nagasaki (lat. 33" 5' N., long. 128" 22' E.; lat. 33" 35' N., long. 128" 22' E.; lat. 33" 5' N., long. 129" 24' E.), (Telegraph-engineer Schonau), I have examined some small fragments of prismatic branches from Japan, found in the root-tuft of an Eupleciella sp., (lat. 32" 12' N., long. 128" 15' E. Captain Suensson).
I have earlier although with some doubt identified this species with T. Sinitti Hincks, and therefore the figures are designated with that name. I am, however, at present, inclined to think that T. Smitli is distinct from all the other species here described.
Thalamoporella Rozieri Aud. Flustra Rozieri Audouin Descript. de I'fc^gypte, Hist. Natur., Tome 1, explic.
sommaire d. Planches, pag. 239. Polypes PL 8, figs. 9* 9'*. Steganoporella Rozieri Hincks, Form. 1, 2 & 3 (non. 4) Annals Nat. Hist.,
ser. 5, Vol. VI, 1880, pag. 28, PI. XVI, figs. 1, 3. Membranipora Rozieri Husk, Catalogue of Marine Polyzoa, Part I, pag. 59,
PI. LXV, fig. (). Membranipora gothica Busk, Quarterly Journal micr. Science, Vol. IV, 1856,
pag. 176, PI. VII. figs. 5, 6, 7. (1^1. VI. figs. 6a-6k; PI. VI b, figs. la-3b). The length of the zocEcia is between 0,48 and 0,79'""', and the distinctly marked adoral areas may be developed, sometimes even in the same colony or in the same zoa^cium, to a varying extent and in different ways. The aperture, the size of which may be contained from 'l^j., to 4 times in the whole length of the zooe- cium, has at least in the youngest zooecia a broad and deep sinus, which how- ever in a certain variety is wholly or partly Tdled by a somewhat projecting lip. The anier of the aperture is as a rule semi-elliptic or semi-oviform, but some- limes the lateral margins may be more or less approximately parallel. The proximal margin of the operculum is generally provided with a continuous chitin- ous sclerite, which is but rarely broken in the centre. Of the two opesiulai the one as a rule only reaches the corresponding lateral wall and but seldom touches the basal wall in a small curved line. The other always reaches the basal wall, most frecpiently touching it in a closed (i. e. meeting the margin of the zooecium with both ends), irregularly tongue-shaped, curved line, more seldom in an open, longer or shorter line, corresponding with a larger or smaller proximal jjart of Ihe closed, curved line. The frontal wall of the polypide-tube is generally deeply depressed proximally.
182
The spicules ajjpear both in the shape of curves and of compasses, hut both these forms show a considerable range of variation not only as to dimensions but also in shape.
The ooecia, which need a closer examination, are very broad.
The avicularia. generally consideral)ly smaller than the zocecia, have a man- dible in the shape of an isosceles triangle with lateral margins curving outwards a little. The opercular arch has also the shape of an isosceles triangle, and its two curved sides, situated a little inside the lateral margins, meet at the point of the mandible.
The description of this ai)])arently widely spread and freipiently occurring species is based on material from many dilTerent localities. The species is ex- ceedingly variable, and as a necessary supplcmeni to the account above 1 shall here give short descriptions of a number of varieties, which no doubt may be largely increased.
Var. A. (labiata).
(I^I. VI, figs. 6 a— Oj).
Length of zooecia 0,45 — 0,57""" The aperture measures, the sinus included, about one fourth of the whole length of the zoa^cium. It has in a greater or smaller number of zooecia a more or less developed, often dentate and longitudinally furrowed, somewhat projecting lip, which entirely or partly fills the original sinus. The two adoral areas are well developed, frequently with acropetal spines, seldom without. The margins of the two opesiuhc are often spinous, and only the one opesiular outgrowth reaches the basal wall, which it meets in a closed, narrow, tongue-shaped, curved line, pointing inwards and a little proximally. The distal wall of the two lateral recesses is only provided with a small, sometimes extremely small foramen.
Spicules. Length of curves varying between 0,026 and 0,186"'"' and that of the compasses between 0,039 and 0,093'""'-; but besides the variation found within the same zooecium both with regard to dimensions and form, some variation in both respects is also found in colonies from different localities. The variation is great- est in the curves, and they reach their maximum in the colony from the Formosa Channel, in which they also have a more even and less sharp curvature.
Localities: Paumben, India (Fristedt), covering algae from a deplli of 1—2 fathoms; Singapore, India (Consul S. Gad), covering algae from low water; the Formosa Channel, lat. 23" 20' N., long. 18" 30' E., depth 17 fathoms, (Andrea). This last form, which is without spines and in which the above-mentioned lij) attains its highest development and occurs at the earliest stage, is found in two-
183
layered, free, maze-like, branching colonies with broad and flat, partly curved and twisted branches.
Closest to this variety some small colonies must be classed, which form cov- erings on algae from Geograph Bay, W.-Australia (on Vidalis spiralis, Botanical Museum), from Jamaica (on Boihnjolhnmninn Seaforthi, the herbarium of Prof. Lange) and from Wyecombe Bay (on Saryassiim scabripes, Bot. Mus.). In all of these, well-developed acropetal spines are found, but the lip is slightly developed or absent, and in a greater or smaller number of zooecia a division of the cryp- tocyst into several areas, separated by sutures, is found, similar to what is known in Th. Jeri'oisi and Th. mamillaris. In the colony from Geograph Bay the lateral margins of the aperture are almost parallel.
Var. B. (sparsipunctata).
(PL VI Ij, figs. 3 a— 3 b).
Length of zocecia 0,66 — 0,73"""- The aperture, the size of which is a little more than one-third of the entire length of the zooecium, has a broad and deep sinus. The more or less developed adoral areas have no spines, and tlie smooth cryp- toc3^st has generally only a few scattered pores. In most cases, I think, both the ojjesiular outgrowths reach the basal surface. The larger meets the latter in a closed curved line, generally very large, angularly arch-shaped and pointing obli- quely towards the proximal end. The other opesiular outgrowth also touches the basal wall in a closed curved line, which however is very small, and both curved lines have frequently one leg springing from the margin of the distal wall.
Spicules: Length of curves between 0,026 and 0,079'"'", of compasses be- tween 0,073 and 0,33"""-
Of this form I have examined some fragments of free, partly hollow, partly solid, vincularian colonies from Port Denison, Queensland (The Museum of Zoo- logy at Cambridge, England).
Var, C. (prominens).
(PI. VI b, tigs. 1 a-1 f).
Length of zooecia 0,53 — 0,66™"^- The aperture, the length of which may be contained 2'/^ — 3 times in the whole length of the zocrcium, is furnished with a broad and deep sinus, and its lateral margins are parallel proxinially. The two adoral areas may sometimes be flat, sometimes furnished with acropetal spines of extremely ditTerent width and length, but generally circular in transverse section. Of the two opesiular outgrowths only one reaches the basal wall, touching it in a rather long, open, generally hook-shaped or angularly bent line.
184
The avicularia, which vary considerably in size, may sometimes attain the size of the zocecia, and their distal opercular part protrudes often sharply, some- times almost vertically from the surface of the colony.
Spicules: The length of the rather slender curves varies between 0,026 and 0,1 IS""""-, of the compasses between 0,06(5 and 0,3;5"""
Of this form I have examined a number of colonies from Torres Straits (Haddon), i)elonging to the Museum of Zoology al Cambridge. Some of these are incrusting, others make free, partly hollow expansions of one layer, and still others consist of a number of very differently shaped, partly two-layered and flat, partly cylindrical segments, which are movably joined by chitinized belts of a dark colour (fig. 1 a).
Var. D. (gothica).
Membranipora gothica Busk.
The zooecia arc of an elongated, hexagonal, rounded form, and their length is from 0,59 — 0,70'"™ The aperture, the length of which may be contained 2^1.,- — 'S times in the whole length of the zooecium, has a broad and deep, some- times trapeziformly rounded sinus and lakes up so great a pari of the breadth of the zooecium, that the adoral areas are much reduced or completely wanting. No spines. The two opesiulae are only separated from the ajierture by a narrow bridge, and but the one opesiular outgrowth reaches the basal wall, which it meets in a generally rather short line, bent like a hook. Numerous and partly rather large pores.
Spicules. The length of the curves is between 0,039 and 0,079"'"- and of the compasses between 0,093 and 0,305™"'-; as however most of the zoa-cia were without operculum, and a great deal of the .spicules apjjeared to be absent, the limits of the dimensions may prove to be somewhat wider.
Of this form I have had the opportunity of examining a piece of Busk's ori- ginal specimen from Mazatlan, for which my best thanks are due to the Director of the British Museum.
Var. E. (californica).
(1^1. VI b, ilgs. 2n— 2cl). The length of the zooecia is between 0,59 and 0,80"'"' and that of the aperture may be contained 3— 3V2 times in the entire length of the zooecium. The two adoral areas may be level or provided with acropetal spines which are sometimes very small. But one of the two opesiular outgrowths and only in about half of the zoaxia, reaches the basal wall, which it joins in a very short, ascen-
l.So
ding, open, cnrved line. Nothing can l)e said witli regard to the dimensions of Hie spicules. Hie small fragments examined having no doubt lost most of these structures, of which only a few curves were left.
A few, very broad ooecia were found, showing a slriation starting from the central suture. The operculum of the gonozocecium has two frontally convergent but not concurrent chitinous sclerites.
Of this form I have been able to examine some laminate fragments from California (Hindi's Collection), belonging to the Museum of Zoology at Cam- bridge.
Thalamoporella novae hollandiae Haswell.
Vincularia novae hollandiae Haswell, Proceed. Linnsean Soc. of New South Wales,
Vol. V, Part I, 1880, p. 41, PI. Ill, fig. 3.
(1^1, Via, ligs. 3a-3t).
The zooecia, whose lateral margins are often more or less sharply angularly bent, are 0,066 — 0,079"™ long. The length of the large wide aperture, which has a broad and deep sinus, may be contained 2'/2 — 3 times in the whole length of the zocecium, and the adoral areas, always without spines, are much reduced or quite absent. The operculum has only in the older zooecia a continuous, but extremely narrow proximal sclerile. As a rule only one of the two opesiular out- growths reaches the basal wall, which it meets in a somewhat variable, but most often irregularly tongue-shaped, closed curved line, pointing obli(piely towards the proximal end; one leg of the line may sometimes join the distal wall. The other may however also — in some cases in about half of the zoa'cia — reach the latter in a much smaller, but also closed curved line. The cryptocyst is very tuberculous, surrounded by strongly developed, irregularly crenulated prominent margins and furnished with numerous, rather large pores. The polyj)ide-lube is short and its frontal wall not much depressed.
Spicules. Only compasses occur, varying in length, between 0,066 and 0,505"""-, as also in respect to the angular bending of the legs. In the smaller of llieni, which are also found between the cryptocyst and the covering membrane, the angle varies between 98" and 110"; but there is no definite limit between these and the longest, which are very slightly curved, and the size of the angle seems to increase according to the length.
Ooecia are not found.
The avicularia. which may attain about the size of the smaller zooecia, are furnished with a strongly developed and deeply depressed crj'ptocysl. The man- dible, the proximal part of which is contracted, has otherwise the form of a
186
broad, oblique, rounded (luiidrangle, iiiid only about Ibe middle third is occupied by the mandibular cavity, which is irregularly vase-shaped and surrounded by a thin, wide marginal expansion.
The colonies are partly incrusting, partly free, with slender, hollow branches. I have examined a number of colonies of this species from Torres Straits and from Port Denison, Queensland, belonging to the Museum of Zoology at Cam- bridge.
Thalamoporella falcifera Hincks.
Steganoporella Rozieri, Form falcifera Hincks, Annals Nat. Hist., ser. 5,
Vol. VI, 1880, pag. 28—29, PI. XVI, fig. 2.
(PI. VI b, figs. 6 a-C e).
Length of zooecia 0,53 — O.Gfi'""" The aperture, the size of which may be contained 3 — 4 times in the whole length of the zorecium, has a broad and deep sinus and parallel or almost parallel lateral margins. The operculum has only a short chitinous scleritc on either side proximally. The clearly defined adoral areas are well developed and have generally small and low acrojjctal spines, which only take up a small part of their surface. The two opesiular outgrowths gener- ally reach the basal wall, one of them only touching it in an extremely small, closed or open, curved line, while the other meets it in a considerably larger, open, recurved line. The finely tuberculous cryptocyst has widely scattered pores.
Ooecia are not found.
The avicularia are rather small with a very well developed, distal cryptocyst and a very narrow, pointed, sabre-like, curved mandible without a marginal ex- pansion, the entire breadth being occupied by the mandibular cavity.
Of this species, which incrusts alg;v, I have examined colonies from the Java Sea (Andrea), on Sargassiim biixifoliiini from (]ampechc Bank, Yucatan on Sar- yassiim hijstrix (the herbarium of algae in Botanical Museum), on Sargassnm sp. from lat. 23" 30' N., long. 40" W. (Andrea) and on Vidalis spiralis from Geo- graph Bay, Australia.
Thalamoporella Harmeri n. sp.
(PI. Vic, lif^s. la- 111). Length of zooecia 0,53—0,57'"'" The aperture, the length of which may be contained a little more than 2'/3 times in the whole length of the zou-cium, has a broad and deep, often trapeziformly rounded sinus. The oi)erculum is attached by two unusually strong hinge-teeth, and the whole of its marginal portion is unusually strongly cbilinized, so that its surface shows a marked contrast between
187
this yellow marginal part and a lighter, rounded triangular central part. The lateral margins of the operculum are more than usually convergent frontally, and, aj)art from its proximal concave margin, its form may he described as rounded triangular. The two distinctly marked, well developed adoral areas are furnished with two large acropetal spines, oval or circular in transverse section, which never show any distinct, radiate, but often an annular striation. Of the two opcsiulre the larger is of a rather long triangular shape and directed towards the proximal opjiosite corner. As a rule both oi)esiular outgrowths reach the basal wall, but with regard to the way in which they meet the latter we may dis- tinguisli between two different cases, which judging from the samples examined seem to be about C(|ually fre([uent, occurring in detached patches at small inter- vals, hi one case they meet the basal wall in two separate, open lines, of which one is extremely short, straight or curved, while the other is considerably longer and very hooked. In the other case we have, as in Tit. lioliclm, a single continu- ous transverse line, but often with an irregular angular bending, in which case the polypide-tube has a low basal wall of its own (tig. 1 f). Transitional stages are however also found between the two cases. The polypide-tube is very asym- metrical and its frontal wall, the [jroximal part of which is much depressed, is smooth on the greater j)art of its surface while on the other hand its distal margin is abundantly furnished with tubercles. The cryj)tocyst is otherwise smooth but has rather large, closely situated pores, which however often do not reach very far.
Spicules. Only compasses occur, the length of which may vary between (),0.'59 and 0,345'"'" In the smaller of them, found both in the zo(pcial cavity and between the cryptocyst and the covering membrane, the angle generally varies between 115" and 123", while the largest, found only in the zoa'cial cavity, are only slightly curved.
Ooecia occur in several places of the examined colony in more or less close groups, partly composed of more or less regular transverse series. Their surface, which shows a more or less distinct concentric striation, is furnished with a greater or smaller number (not exceeding about twenty) of rather large, pyriform pores. The gonozooecia, which may become longer by a half than the ordinary zoa-cia, have a very large aperture which aj)art from the sinus makes four-fifths of an ellipse. The operculum of the gonozoax'ium has a closed, chitinous curved sclerite reaching the distal third of the operculum (fig. 1 e).
The avicularia, occurring in large numbers and somewhat smaller than the zoa'cia, have a slightly developed distal, and a more strongly developed proximal cryptocyst. The uuuidible has as in 77i. Rozieri the form of an isosceles triangle
ISS
Nvitli lateral margins curving outwards, and has likewise two lateral expansions, which are separated from the niandihular cavity hy the triangular opercular arch. The marginal portion of the mandihle is chitinized to an unusual degree. This species, which incrusts a red alga from Madagascar, belongs to the Mu- seum of Zoology at Cambridge, and has been kiTidly lent me for exaiuinaliou of Dr. S. Harmer.
Thalamoporella granulata n. s|).
(I'l. VI :i, lit^s. 1, 2; I'l. VI, 11}^. .')).
The length of the zooecia may vary between (),')',V2 and (),9;{""" The aperture, the size of which may be contained S'/a — 4 times in the whole length of the zooecium, has a broad and deep sinus, which is generally separated from (be remaining semi-circular or semi-oval part by strongly developed hinge-teeth. The proximal margin of the opercidum has on either side an extremely short chilinous sclerite. The two indistinctly marked adoi^d areas are usually slightly ileveloped, but may be furnished with small, round acropetal sj)ines. The two opesiula* show as a rule no great difTerence in size, and llie oj)esiular outgrowths both reach the i)asal wall, meeting it in two open hooked lines, which may l)e ecju- ally large. The frontal wall of the polypide-tube is not very deeply de|)ressed, and the cryptocyst, which has a strongly developed, crenulated or tuberculated marginal part, is on the whole of its frontal surface more or less strongly tuber- culous. Numerous, rather large pores.
Spicules occur both in the shape of compasses and curves, and particularly the latter show rather a wide range of variation. The smaller spicules are also found between the cryptocyst and the covering membrane.
The ooecia, which are without pores, have a rounded triangular outline and a somewhat projecting aperture. The gonozooecia are of about the same size as the ordinary zoo^cia, and the chitinous arch of the operculum is not far from the margin.
The avicularia. which may reach and even exceed the length of the zoircia, have a strongly developed distal cryptocyst. The mandible is sometimes narrow and tongue-shaped, sometimes i)road and more or less regularly lyriform or vase-shaped.
Var. A. (stapifera).
(I'l. VI, li^s. 5a— 5 e). The zo<Ecia, whose length generally varies from 0,798 to 0,9;5'""' , are most often of a rounded hexagonal form, frequently unusually l)road and Hal. 'i'he adoral
189
areas have often small, round acropelal spines. The cryptocysl very tuberculous and furnished with closely situated i)ores.
The avicularia, which are extremely rare, have a long, narrow, tongue-shaped mandii)lc.
Spicules. The length of compasses found varies between 0,053 and 0,186™™, and the length (iieight) of the curves between 0,033 and 0,039™™ The latter, which are much higher than broad, have a peculiar stirrup-like shape, and Ihe legs are rectangularly bent at the end, while at the same lime the median knot is unusually strongly develo|)e(l and conically pointed. Il must however be remarked that the zoa'cia in I In- colonies examined have lost most of their spicules.
This form has partly been found on a Trulaciui, the locality of which is unknown, partly on a Haliotis from the Andaman or Nicobar Islands (de Roep- storfT).
Var. B.
(PI. Via, lifJis. 1 :i-l f).
The zooecia, Ihe length of which varies from 0,598 to 0,731""», are usually rectangular, rarely furnished with somewhat angularly bent or curved lateral margins. The adoral areas have no spines, and the cryplocysf is less tuberculous and has fewer pores.
The avicularia are rather numerous and have a broad irregularly vasiform or lyriform mandible, the mandibular Cavity of which hardly occupies one-third of the entire breadth and is bounded by two subparallel chitinous margins at the point concurrent.
Spicules. Length of compasses varying from 0,046 to 0,292™'" , and Ihat of the unusually smal curves from 0,013 to 0,033™™- They differ from Ihe curves iii Var. A. in being less high, in having a less developed median process and a more curved bending of the point of the legs.
Of this form I have examined some fragments of hollow colonies and some small one-layered lamina> from Torres Straits (Haddon), belonging to the Museum of Zoology at Cambridge.
Var. C. (tubifera).
(PI. via, (igs. 2a-2c). The zooecia, the length of which may vary from 0,532 to 0,731™'", are fre- quently rectangular, sometimes however furnished with somewhat angularly bent or curved lateral margins. The adoral areas have no spines, and the cryptocysl
190
is strongly tuberculous and lias numerous poies. The polypifle-tuhe lias in hy far the greater part of the zocecia a distal continuation in the shape of a thin- walled calcareous tube whose basal wall as that of the i)rQximal part of the tube is formed by the basal wall of the zoo'cium. With its closed distal ])art it touches the distal wall at the basal part of the latter, so that the rosette-plates lie within its region, and its frontal wall springs from the inner surface of the bridge between the two opesiuke, nearly at the distal third of the latter. This tube, also found in the avicularia and in the gonozoa'cia, in the latter of which it has the form of a trapezoid ((ig. 2 b), each obtuse corner of which ends op- posite a rosette-plate, generally grows narrower upwards and is not infre(|uently furnished with a lateral branch, leading to one of the rosette-plates of the lateral walls. A little proximally to the closed end it has — probably for the extrusion of the polypide — an oval or round 0])ening. In the avicularia this opening is situated, far back.
The avicularia, which are not uncommon, have judging from the form of the aperture, a regularly vase- or lyre-shaped mandible.
Spicules. Length of compasses varying from O.OHG to (1,399™'"- and that of the curves from 0,039 to 0,066"""-
Of this form I have been able to examine some fragments of uni-layered laminae from Deboine Lagoon, Louisiades at New Guinea, belonging to the Museum of Zoology at Cambridge.
Thalamoporella expansa n. sp.
(PL VI b, ligs. 5a-5e).
Length of zooecia varying between 1,06 and 1,33""" The aperture, measuring about one-third of the entire length of the zotecium, has a most singular appear- ance on account of the peculiar structure of the distal wall. The frontal part of the latter namely ascends so sharply as to make the angle, that it forms with the cryptocyst of the higher zooeciuni, approximately 180°, its form being that of a large, flat, slightly deepened, semi-circular, aureola-like extension distally to the other part of the a])erture, which we may call the real aperture. This is of a semi-elliptical form with a proximal, slightly concave margin, which is some- times completely filled by a low, slightly projecting dentate furrowed lip with a straight margin. The oral shelf, as usual springing from the boundary between the more horizontal part and the ascending part of the distal wall, is unusually well developed and in the shape of an arched lamina directed obli(juely towards the zocecial cavity. The operculum, which is more strongly chitinized than in the other species of this genus, has a straight proximal margin and is in con-
191
formily to the aperture, composed of two difTerent portions, one corresponding with the aureola-like expansion, and one answering to the real aperture. While the former occurs as a uniform chitinous expansion, the latter is provided with a strongly chitinized proximal margin, and with a most chitinized opercular arch, the two arms of which have in their distal half a small rounded process for muscular attachment. The two adoral areas are furnished with two sometimes small and sometimes medium-sized, not very projecting spines of a round or oval section, and they are connected with each other by a very narrow and low, raised margin. The cryptocyst is extremely fuberculated, encircled by a well- developed, crenulated, tuberculous marginal ridge and furnished with closely situated, rather large pores. The two small opesiulai, which are widely separated from the aperture, most frequently circular, more rarely oval, and in which the margin is usually more or less sinuated owing to the very tuberculous condition of the cryptocyst, generally show only a slight difference in size. The opesiular outgrowths both reach the basal wall, which they meet in two closed, ([uadrang- ularly rounded, somewhat distally bent curved lines, which show less difference in size than is usually the case in the species of this genus. The bridge between the two opesiulse is short and broad, very slightly depressed and has con- trary to the rule not infrequently a larger or smaller number of pores in its j)roximal half.
Spicules occur only in the shape of compasses, of which the smaller are rather strongly l)ent at an angle and also found between the cryptocyst and the covering membrane. Length varying from 0,039 mm. to 0,718™"' Ooecia are not found.
The avicularia, which are rare and much smaller than the zoa^cia, have a very well-developed proximal cryptocyst, surrounded by a thick, marginal ridge. The mandible is semi-elliptical and has a mandibular cavity in the form of an isosceles triangle.
Of this species I have examined firstly some colonies, incrusting Tridacna sp. without locality, and secondly^ some one-layered laminae from Torres Straits, be- longing to the Museum of Zoology at Cambridge.
In some of the polypide-less zoacia I found a narrow, thin-walled, somewhat curved calcareous tube, passing through the whole length of the zou'cium and including the roselle-plales of the two opposite distal walls. It had several lateral branches, which reach the rosette-plates on the lateral walls, and in some cases at least I have found a round or oval opening in the frontal wall of the distal end of the tube. This lube is apparently of the same nature as the one, men-
192
tioned in Tli. (jrimnhila, Var. C, in which form il was only a conlinuation of the polypide-lube. Most likely we have here a peculiar form of regeneration.
Thalamoporella cincta Ihitlon.
Membranipora cincta, HiiUon, l^rocccd. R. Soc. of Tasmania (1877),
1878.
Memhrani])ora transversa, Hincks, Annals Nat. Hist., ser. 5, Vol. VI,
1880, p. 21, PI. XI, fig. 9.
Diploi)ora cincta Mac Gillivray, Trans, and Proceed. H. Soc. of Victoria (1880), 1881, Vol. XVII, p. 15, lig. 1 — 1 c. (PI. XXII, lif^s. 7 a— 7 (I). The zocecia, which are rather long and rectangular, have a length of 0,598— 0,6'"'"- The large aperture, the size of which may be contained ;J7s — 4 times in the whole length of the zoa-cium, has a broad and deep sinus, and the more or less developed adoral areas have always acropetal spines, most frecjuently of a somewhat compressed conical shape. The operculum, the concave proximal margin of which is in the whole of its length furnished with a well developed chitinous sclerite, has within each lateral margin a somewhat curved, chitinous ridge, which on its internal side is proximally connected with a much shorter chitinous part, distally ending in a small rounded expansion. Of the two opesiular outgrowths only one reaches the partly or wholly uncalcified basal wall willi a shorter or longer part of its proximal margin, while the other, which is very small and sometimes difficult to distinguish from the frontal surface, only reaches the apper- taining lateral wall. A little distally to the centre a short, but broad deepening occupies the whole breadth of the frontal surface, and at the bottom of this deepening the larger of the two opesiuhe is found on one .side and on the other a deeply dej)resscd part of the polypidc-tube. The smaller of the two opesiulae is generally situated immediately on the distal side of this deepening and in some cases at its distal end. While the region between the aperture and the deepening may be .sometimes quite smooth, sometimes with rather numerous tubercles, but never with pores, the remaining part of the cryplocysl, which is extraordinarily, sometimes almost rectangularly arched, is furnished with numerous tubercles and small denticles in its distal i)arl and numerous pores in its proximal part. Also the inner .surface of the lateral walls is very tuberculous and spinous. In the proximal half of the zocrciuni each lateral margin expands into a strong, some- what compressed but thick process with two arched lateral surfaces and of a semi-circular or triangularly rounded outline. These processes, the outer surface of which is distinctly transversely striated, are more or less inclined towards
19H
the cryptocyst, and the two belonging to the same zooecinm may sometimes nearly reach each other. Contrary to the rnle each distal wall is furnished with two multiporous rosette-plates.
Spicules. Only compasses are found, measuring from 0,053 to 0,265'"'"- and varying greatly with respect to the angle made bj' the legs. While the angle in the smaller ones is about 113", it approaches 180" in the longest, which are only i'oiuid in the zoo'cial cavity.
Ooecia are not found.
The avicularia, occurring less numerously among the zooecia and only about half as large as the latter, are quadrangular or ])entagonal, and the triangular mandible has rather curved lateral margins.
Of this species I have examined two dry colonies from Port Phillip, found in the collections of Algic at the Botanical Museum. The zooecia of the two colo- nies, which form a covering on cylindrical algal stems, are arranged in an- nular belts.
Thalamoporella Jervoisi Hincks. Steganoporella Jervoisi HincUs, Annals Nat. Hist., ser. .5, Vol. VI, 1880, pag. 30, PI. X, fig. 9. (PI. Via, figs. 4a-4c). The length of the zocecla varies between 0,532 and 0,798"'™- The aperture, the length of which may be contained 3 — 4 times in the whole length of the zoo?- cium, is unusually long and has a very slightly developed, sometimes almost imperceptible sinus small both in depth and breadth. The operculum, the chilinous arch of which is strongly developed, has a continuous, distally curved proximal sclerite and a greater or lesser part of the membrane filling the proximal part of the aperture is chitinized together with the operculum (not to be seen in the figure 4 c, which does not show either the thin marginal portion outside the opercular arch), the proximal margin being in this way either straight or a little convex. Each of the lateral margins has a slight incurvation and within this the opercular arch is provided with a small |)rocess for muscular attachment. The sharply defined adoral areas are well developed with large, cone-shaped-cylindrical, somewhat compres.sed acropetal spines. Of the two opesiula; the larger is gener- ally very narrow, almost slit-like and pointing obliquely and inwardly towards the proximal end. The other is very small. The opesiular outgrowths both reach the basal wall, the larger touching it in an open, hook-shaped curved line, while the other meets it in a very short, ascending line. The cryptocyst the central part of which is much depressed lacks a raised marginal portion and is most
13
194
often divided by sutures into four segments, ascending towards the margins of llie zocecium, namely, a distal, a j)roximal and hvo lateral, joining each other in a short sutiiral line. It is however not uncommon that an area fuses with a con- tiguous one, as e. g. the proximal area and a lateral one in fig. 4 a. While the proximal area and the two lateral are more or less closely set with small scat- tered i)ores, the distal one is only furnished with small tubercles, which are most numerous just proximally to the aperture.
Spicules. Besides curves, the length of which is between 0,026 and 0,113'""', a peculiar intermediate form occurs, with two unequally long arms, of which the longer is formed as an arm of a curve while the shorter is like that of a compass. Their length varies from 0,1 OG to 0,46™"'
Ooecia are not found.
The avicularia, of which none were found on the i)iece examined, are accor- ding to Hincks rather uncommon, very small and with a triangular mandible. .Judging from the figure there is a calcified transverse bar between the opercular and the subopercular areas, a character not found in any of the other sj)ecies.
Besides a fragment of the original specimen, which I owe to the kindness of Mrs. H. Eden (nee Gatty), I have examined a small colony from Port Phillip Heads, Victoria, sent me by Mr. J. Gabriel.
Thalamoporella mamillaris Lamx.
Membranipora mamillaris Hincks, Annals Nat. Hist., ser. .'S, Vol. VI,
1880, pag. 88, PI. X, fig. 9.
(PI. Via, figs. Sa-.'ic).
The length of zooecia varying between 0,532 and 0,665'""' The aperture, the length of which may be contained 3 — 4 times in the whole length of the zocecium, is bounded by two, more or less convergent lateral margins and by an almost straight proximal margin. The horizontal basal part and the ascending frontal part of the distal wall are not sharply delimited, and an oral shelf is wanting. But some way within the free margin of the aperture and ])arallel with it is a very narrow, low, glistening, usually beaded arch. The operculum, the arch of which appears to be situated immediately within the free margin, has a proximally incurved, extremely narrow chitinous .sclerite, but the part of the covering membrane between the operculum and the distal margin of the cryplo- cyst is more chitinized than the rest of this membrane and is (bus connected with the real oijitcuIuui to a continuous whole. The two distinctly marked adoral areas are well-developed and have large, compressed, conical acropetal spines. Only one tongue-shaped opesiula is ibuiui, the direction of which is obliquely
195
proximal and inward, and the opesiular outgrowth touches the basal surface in an open, hooked, curved line. The proximal margin of this opesiula has a series of from 3 to 7 distally-pointing spines, partly more or less branched, partly single, and both its margins are moreover furnished with larger or smaller laminate processes of varying shape, which generally point more or less obliquely towards the opesial cavity and are more rarely on a level with the opening of the latter. They maj' be curved, lobed, sinuous or even furnished with branched processes (fig. 5 b). On account of these marginal expansions the entrance to the opesial cavity is often made very narrow and in some cases by partial fusion of two such opposite portions reduced to a small hole. The cryptocyst, which in older zooecia may have a raised margin which is rather broad especially in the proximal part of the zooecium, is, as in Th. Jervoisi, divided into four, sometimes three segments, as the distal or the proximal one may have fused with one of the lateral parts. The ojjesiular opening cjuite separates the distal area from one of the lateral ones, and the area opposite that of the opesiula is in most cases furnished with from 2 to 5 partly single, partly branched spines. With the excep- tion of a very tuberculous belt immediately on the proximal side of the aperture, tubercles only occur in very small numbers, the greatest number being found in the proximal area, which is also the only one to show a few small pores.
Spicules. Only compasses occur, the length of which varies from 0,033 to 0,133™™-, and of which a great many are more or less strongly curved.
Ooecia are not found.
The avicularia are rather uncommon and much smaller than the zooecia. They have a small triangular mandible with a rather long, linear terminal part. A larger or smaller part of the subopercular area is furnished with a very thin, not deeply depressed crj'ptocyst lamina ending in a dentate margin.
In one place a smaller number of narrow, abnormal zoa'cia were found, the cryptocyst of which consisted partly of a generally very broad, and sometimes strongly prominent marginal portion, the inner edge of which is broadly crenu- lated, and partly of a depressed, more or less tuberculated median portion. The marginal portion, divided by sutural lines into numerous small areas corresponding to the crenulations may attain so great a breadth that its two lateial halves may coalesce sometimes in the distal and sometimes in the proximal part of the zoa*- cium. In the distal half of the zocrcium there is frequently a somewhat vary- ingly shaped, round or oval aperture without operculum.
A small colony of this Australian species was kindly placed at my disposal by the late Mr. Peal.
13»
196
Family Setosellidae ' n. 1'. Setosella Hincks.
The zoii'cia the frontal wall of which is perforated by two slit-shaped opes- iulae have a well chitinized simple oporculuiii with a well developed opercular arch. No spines. The lateral walls which are comnion to the contiguous zoci'cia are in their distal jjart provided with a large membranous, uniporousC?) rosette- plate. Obliquely, distally to each zooecium is found an independent i>il>r(iciiliim without a cross-bar, with a long, strong, dentate flabelluni. The ocrcia are small rounded cavities in the frontal wall of the arched distal part of the gonozoa'cium, the 'ooccial areas which is distinctly separated from the lateral jiarts by an impressed line. The ooecial cavity which is distinctly apparent on the outer sur- face opens out through a hole gradually increasing in size.
The Goecia of the present genus, which have hitherto been overlooked, belong to the same division of ooecia (p. 65), the endotnichal, found in the genera Cellii- laria and Membranicellaria, but while in these they are placed in the proximal pari of the frontal wall, they are in Setosella placed in the distal part of this wall.
While the aperture of the common zoa-cia is about as high as broad the aperture of the gonozoa'cia is broader than high, with a somewhat convex proxi- mal margin and with two acuminated corners.
On account of the ooecial form I have thought il necessary to set up a new family for this genus which is represented by a single s[)ecies i". viilnerala IJusk. Of this species colonies have been taken by the Ingolf Expedition at Lat. 25" 21' N., Long. 63" 21' W., at a depth of 170 fathoms.
Family Chlidoniidae.
The jointed colonies, springing from a stolonate network, consist of a stem, two main branches and a number of zocccia-bearing secondary branches, and besides the zocecia we may distinguish between three different forms of kenozooecia, namely the partitions of the stolon, the stem-internodes and the bifurcate inter- nodes of the main branches. Moreover, the main branches and the secondary branches end in a number of small cylindrical internodes, of which those in the •secondary branches may be transformed into zooecia. The zooecia, which lack pores and spines, have a deejjly depressed cryptocyst, pierced by a small trans-
' Neither this family nor tlie family Crepidacantbidae arc naimd in the synopsis on p. 88, both families having been founded later.
197
verse slit, and have a simple, semi-elliptical operculum, ending in a straight proximal margin. The stem-internodes have a small depressed cryptocyst with one pore at the bottom; and excepting the partitions of the stolon the other in- dividual forms have their inner cavity divided into a series of segments (gener- ally four), separated by more or less sharp constrictions. The distal walls have a single-pored rosette-plate. Ooecm and avkularia wanting.
Chlidonia Cordieri Aud. Eucratea Cordieri Audouin, Descript de I'Egypte, Hist. Natur., Tome 1,
explic. sommaire d. Planches pag. 242, Polypes PI. XIII, fig. Sj— 83. Eucratea Cordieri Waters, Annals Nat. Hist., ser. 5, Vol. Ill, 1879, pag. 116,
PI. XV, figs. 9, 10, 11. Chlidonia Cordieri d'Orbigny, Paleontologie Francaise, Terrain cretaces,
Bryozoaires, 1850 — 52, pag. 40. Cothurnicella dsedala, Wyw. Thomson, Nat. Hist. Rev., Vol. V, pag. 146. — — Wyw. Thomson, Dublin Univ., Zool. Bot. Assoc,
1859, pag. 85. Chlidonia Cordieri Busk, Challenger, Zoology, Vol. X, 1884, pag. 8,
PI. XXVIII, fig. 11.
— — Hincks, Annals Nat. Hist., ser. 5, Vol. XVII, pag. 258.
— daedala Mc Coy, Zoologie of Victoria, dec. XI, pag. 35,
PI. CVIII, fig. 2.
— — Mc Gillivray, Catalogue of the Marine Polyzoa of Vic-
toria, pag. 10. Chlidonia Cordieri Waters, Journal Linnean Soc, Zoology, Vol. XXVI, 1896, pag. 18, PI. 1, fig. 8—9.
— — Calvet, Bryozoaires Marins de la Region de Cette,
pag. 13, PI. I, fig. 1 et 2. (Pl. VIII, fig. Oa-Gy). As our knowledge of this often examined species still leaves a great deal to be desired, I may here give a connected description of it. It occurs as compound colonies, a number of small colonies springing from a reticularly branched, fili- form stolon (fig. 6 i), which may cover various substances. This stolonale net- work is compo.sed of rather long partitions, separated two and two by a single- pored rosette-plate (fig. 6 e), which is surrounded by a thickened, diaphragmatic, projecting part of the inner wall. Each small colony (6 a, 6 b) is furnished with a jointed stem, bearing two main branches likewise jointed, each of which termin- ates in from 4 lu (3 long cylindrical internodes, F'rom each internode of the
198
proximal (inner) half of such a main i)ianch a secondary branch is given off, and excepting the extreme, or more rarely the two extreme secondary branches on each side, which bear a row (4 — 5) of cylindrical internodes like those of the terminal parts of the main branches, all the other secondary branches consist in the complete state of a row of zocecia, of which each again ends in a row (3 — 4) of the cylindrical internodes. In such a small colony we may thus distin- guish between four different forms of internodes, namely (1) stem-internodes, (2) bifurcate internodes of the main branches, (3) the zocecia, and (4) the narrow cylindrical internodes. While the colony, when placed on a level, has the form of a stalked fan, the rays of which decrease in length from within outwards, it has in its natural position almost the shape of a ball with a pear-shaped incis- ion on one side bounded by the two main branches (lig. 6 a).
The zocecia (6 d, 6 c, 6 f), the two lateral surfaces of which meet in a poin- ted basal edge (6 s), have, when looked at sideways, an almost semi-circular out- line, though the proximal half of the dorsal surface is a little incurved. The semi-elliptical aperture, situated in the distal i)art of the zooecium, has an almost straight proximal margin and is covered by a slightly chitinized, simple oper- culum, the proximal margin of which is more chitinized, and the opercular arch of which is situated in the margin itself. Proximally to the aperture we find a rather deep cryptocyst depression, occupying almost half the length of the zoa?- ciuni and only separated from the aperture and the lateral surfaces by a narrow marginal portion. The proximal part of the zooecium is arched, sometimes almost stalk-like narrowed and furnished with a very thick frontal wall (fig. 6 d). The cryptocyst is also very thick-walled, particularly the distal part, which projects into the zooecium with a very rounded thickening (fig. 6 d), and in the frontal wall of this portion, proximally to the aperture, a small transversely oval hollow is seen. Further back, in the approximate centre of the length of the zooecium and immediately on the proximal side of the above mentioned, very arched por- tion, is a somewhat larger, transversely oval area, which is removed a little from the central line, and which has a transverse slit in the whole of its breadth. In each zooecium the inner cavity shows four distinctly separate segments, which we may indicate by the letters u, ^, y, 6 (6 c), and the obliquely ascending distal wall, furnished basally with one single-pored rosette-plate, is situated between the segments fi & y.
The stem-internodes (figs. 6 t, 6 u, (i v, 6 x), of which the lowest (6 i) has a long, narrow, chitinized proximal part, are long, spindle-shaped-cylindrical and when fully developed, very thick-walled. The inner lumen is as in the zocecia divided into four segments of dilTerent width and shajjc, a, fi, y, d, corresponding
199
with those in the zooecia mentioned above. Here also an oblique distal wall is found between /S and y, which in the fully developed internodc is only repre- sented by a round, single-pored rosette-plate, and in the distal half of the seg- ment ^ is a narrow, oval cryptocyst depression, the bottom of which is perforated by a round pore, equivalent to the transverse slit in the zocecium. In a very young internode (6 v, 6 x) the calcareous wall is still very thin, and the inner segments accordingly of quite a different shape. The distal wall (dw) has here a considerable extent, and the cryptocyst not yet being formed an oval opening is seen in its place in the calcareous wall, covered by a membrane. The distal stem-internode (fig. 6 h), which bears the two main branches, is a transitional form between the stem-internodes and the bifurcate inlernodes of the main J)ranches, and like these it is divided into two branches, of which however one is very short. The long branch has on its inner side a cryptocyst depression, perforated by a pore like that of the stem-internodes, and the short branch is formed by an u and a /S springing from d. Each branch has a single-pored ro- sette-plate, one situated between /? and d, and the other between /S and ;'. The long branch of the distal stem-internode may in different colonies be directed now to the right side now to the left.
The bifurcate branch-internodes (fig. 6 g), which form the proximal half of the two main branches, have each a d and a y in common; but while the branch of the internodes, which is connected with the next branch-internode, has an u and a /J, which latter issues from the proximal part of y, the branch connected with the zocecium has only a single segment, springing from the end of y. The whole internode has onlj' one rosette-plate, situated between /S and y. The bi- furcate internodes, which bear the secondary branches consisting of cylindrical internodes of which generally only one, more seldom two occur on each side, are much more slender than the others and thus approach to the form of the suc- ceeding internodes. In these also a single-pored rosette-plate is found between /J and ;'.
The cylindrical internodes, which as mentioned not only form the terminal part of the two main branches and of the zocecia-bearing secondary branches, but also form one or two secondary branches on each side, are very slender and thin, and their inner cavity has a contracted part at both ends. No rosette- plates are found between the single joints, and they might therefore hardly be regarded as individuals (Bryozoids).
The number of stem-internodes in the colonies examined is between two and fifteen, and the number of secondary branches ending in cylindrical internodes between nine and fifteen. The number of zooecia in the secondary branches in- creases from without towards the centre and varies in the outermost between
200
one and four, in the most central ones between three and nine. The number of stem-internodes bears no particular relation to either the number of secondary branches or to the number of zooccia in the latter. The number of stem-internodes very rarely exceeds twelve, fifteen having been found only once in a very small colony, the eight secondary branches of which had not yel any cylindrical inter- nodes at the end.
Growth. The youngest colonies I have seen consist only of a few stem-inter- nodes, and that they have not been fragments is sufficiently evident from the fact, that the apical internode had still but a very thin calcareous wall and ends in a membrane. The examination of numerous young colonies in dilTcrent stages shows that such a colony is constantly increasing Ijy direct growth, until the separate zocecia-bearing secondary branches have attained to temporary comple- tion by the formation of the apical cylindrical internodes; however, in the ditTer- ent colonies the secondary branches that have attained this temporary comple- tion may contain rather a varying number of zocecia, and there may also be found a rather great difference in the number of zocecia between the outer and the inner secondary branches. In colonies with IJJ — 15 secondary branches, the number of zocecia of which varies between 2 and 9, this completion is probably always attained, and often it may even be attained by colonies with 10 — 12 secondary branches, the number of zoo'cia of which is between 1 and 7. In all younger colonies, however, a larger or smaller number of secondary branches is found, which end in a funnel-shaped rudiment of a zoa^cium closed at the end by a membrane, which is very rarely met with in secondary branches with more than 5 zocecia.
After the formation of the cylindrical terminal internodes a further increase in the number of zofficia in the separate secondary branches may take place by the transformation of these into zocecia, and this transformation may lake place in two different ways. In most cases a compressed, funnel-shaped body grows from the basal part of the internode (figs. 6j, 6 m, (i r) and surrounds the latter, which increases in extent and graduallj' obtains a wider lumen. Time has not permitted me to examine this development from stage to stage; but the various stages I have seen leave no doubt of the fact, that this funnel-shaped rudiment is the beginning of a zooecium, as, aj)arl from the cylinder arising from its centre, it (piile agrees with the zoo'cial rudiments which arise by direct growth. In the other, less frccjuent case the transformation takes place by a gradual swelling of such an internode (figs, fin — 6 q), which is by and by furnished with an oval depression, presumably corresponding with the cry|)tocyst depression of the zoce- ciura, and further forward with a distal wall. Hutli these forms may be found
201
in the same colony. Such a Iransformation of the cyUndrical iiileiiiodes is found in most of the more developed colonies in one or several secondary hranches, and a growth in length and a division of the younger inlernodcs take place at the same time.
We have already mentioned that in a colony at a certain stage of develop- ment the outenno.st or sometimes the two outermost secondary hranches on each side are only composed of cylindrical internodes, and if we were to examine a numher of colonies at dilTerent stages of development we should lind that these whip-lilie secondary branches i.ssue nearer the top stem-internode in the younger colonies tlian in the older ones. Thus, if we were to designate the internode of a main l)ranch, issuing directly from the hifurcate, distal stem-internode, no. 1, tlie next no. 2 and so on, we should lind that in colonies with 6 — 8 secondary branches the whip-like secondary branches issue from internode 3 — 4, in colonies with 9 — 12 from internode 4-6 and in colonies with 13 — 16 from internode 5 — 7. This fact can only mean that all the zocecia in a number of outer secondary branches arise by a transformation of cylindrical internodes. There is however no certain rule for the time of the appearance of the fust whip-like secondary branch, as in some colonies it may appear later than in others. The outermost secondary branch on each side generally remains untransformed, and I have only in very few cases found 1 — 3j^of the proximal internodes transformed into zoa-cia on one side of an older colony. A consequence of the conception that a number of the older whip-like secondary branches are transformed into zooecia-bearing ones and that new ones are formed outside these is, that the inner cylindrical internodes of the main hranches must at the same time be transformed into bifurcate internodes.
Whilst all the colonies of this species examined by me have arisen by gem- mation from a branched stolon connected with other colonies.a fact explaining the possibility that the development of a colony may begin with the formation of a numher of individuals (.slem-internodes and branch-internodes) without or- gans of nutrition, 1 have no doubt that a colony, proceeding directly from a larva, must begin with the formation of a zocecium. Of this species I have been able to examine numerous colonies obtained from a jointed calcareous alga taken at Ajaccio by Dr. Borgesen.
Family Alysidn'dae.
The jointed colonies, springing from a stolonate network, consist of zo(Ecia and gonozott'cia, the latter borne by stem-like kenozooecia. The zoivcia, the distal half of which has a dei)ressed cryptocyst, are furnished with a simple opercular
202
valve and willi Iwo opesiula*, while the kenozoa>cia, spiingiiii; from the axial zott'cia, have a small dejuesscd c'ryi)locy-sl perfoialcd i)y a pore. All septa have a series of single-pored rosclte-plales. Hivalve (xrcia, in which each valve must be considered a kenozoceciuni. No aviciilarid.
Alysidium parasiticum Rusk. Catalogue of Marine Polyzoa, Part I, Cheiloslomata, pag. 14, PI. XIV',
figs. 6—9. (PI. VII, figs. ;j a-3 o).
The zooecia. which are rather elongated and trai)eziformly rounded, steadily increase in hreadth towards the arched, distal margin. The aperture, the slightly curved proximal margin of which is situated in the distal third of the zoa'cium, is broader than long and has a glistening ridged distal margin, often with a series of small tubercles. There is a membranous opercular valve and the <)|)er- cular arch is situated in the free margin itself. Almost the distal half of the frontal surface is furnished with a depressed cryptocyst, which also occupies the region between the aperture and the distal margin of the zoreciuni. The post- oral cryptocyst, which stretches more than half-way back between the aperture and the proximal margin of the zooecium and which has generally a number (most often 10 — 15) of glistening tubercles, is separated from the remaining arched part of the frontal surface by a semi-elliptical boundary ridge, which is very low in the middle but increasing in height distally and ending on each side at one of the horn-like spines, from which it is separated by a small notch. The.se two spines, situated at the margin of the zoa'cium oj)posite the aperture and standing out almost vertically from the surface of the zoa-cium, have generally a form resembling that of short cow's horns but are a little more compressed. In their proximal inner i)art each of them has a small hole, apparently leading into the inner cavity. On the proximal side of the aperture on each side is a rather small, irregularly rounded opesiula, the inner margin of which nearly always terminates in a short, most often rod-like jjrocess, seldom with two or several points. The two opesiulae are always of dilTerent size, but while in the axial zocecia this difference is slight, it is large in the others where the opesiula facing the axis of the colony is twice the size of the other. Immediately on the proximal side of the two opesiulie is an oblique, glistening stria, which is how- ever rather indistinct in the axial zooecia, passing right across the zooecium to the lateral margins. This stria, which in zooecia of the second and third order is inclined towards the central line of the colony, originates from a low ridge on the inner surface of the cryptocyst, and immediately distally to it is the limit
203
between the two parts of Ihe cryplocysl ot which one is ascending lowanls Ihe apertnre the other descending towards the above-mentioned senii-ellii)lical bound- ary ridge, the two parts forming an oljluse angle. The portion on the proximal side of the opening is also somewhat thickened. The contracted, proximal part of the zocrcium consists of a flexible chitinoiis mass decreasing in thickness as it continues through the thick-walled calcareous bottom, distally to which the narrow lumen suddenly expands into a spacious, asymmetrical cavity, furnished on one side with a blind sac-like continuation directed proximally, which we may term the proximal recess. All the zott'cia are on the whole very asymmetri- cal, which may be seen more or less distinctly in all the different structural features. Thus the basal recess and the larger of the two opesiulai are situated on the same side of the zoa>cium, towards which the above-mentioned inner ridge inclines and the semi-elliptical boundary ridge has also a more or less distinct inclination towards that side. While this side in the axial zoa^cia is the right or the left alternately, it is in all other zoa^cia the one facing the central line of the colony.
The obli(iuely ascending distal wall (figs. 3 d, 3 c), situated rather far back and bent in an arch from side to side, has within its basal nuirgin a series of small single-pored rosette-plates, and according as the zoa^cium is ilistally con- nected with one or three others its distal end is undivided or divided into three smaller pore-chambers. In an undivided pore-chamber I have found <S— 9 rosette- plates.
On the dry colonies examined I found some branches ending in one or two long, narrow, somewhat bent, almost cylindrical internodes, which on the frontal side a little above the proximal end had a pear-shaped hole. It seems natural to suppose that all the terminal zooecia end in this way, and it is possible that their function is similar to that of the cylindrical internodes in Chlidonia.
The ocEcia are borne by separate, small branches (fig. 3 a), which may spring partly from most of the axiai zooecia and partly from a smaller number of the lowest zoa'cia of the second order. They are situated a little proximally to or on a level with the semi-elliptical ridge half-way towards the margin of the zooc- cium, and in the successive zooecia alternately on the right and the left side. In each of these branches, which have an arch-like bending and stand out almost vertically from the surface of the colony, we may besides the two ocrcial valves also distinguish between a gonozoa'cium and a kenozoa^cium, which unites the former with the zoa^cium. In the stalk-like kenozooecium (figs. 3 m, 3 n, 3 o), we may distinguish between a longer and thicker, calcified, ovally club-shaped central part and two shorter, cylindrical, somewhat bent terminal parts consisting
204
of a yellow chilinoiis mass, of which the proximal one serves as a connection with the respective zoa'cium and the other as a connection with the gonozoa'ciiim. The central part has in the distal half of its less strongly arched frontal surface, which is turned towards the colony, rather a deep, oval cryptocyst depression, which is in its proximal part perforated by a round hole, and in its inner lumen we may distinguish between two narrower terminal portions, which are continued through the two chitinized terminal pieces, and a broader central portion, divided into two spaces by the somewhat obli(iue distal wall, the basal part of which has three single-pored rosette-plates (3o), and which meets the gymnocyst im- mediately on the distal side of the above-mentioned pore. In the possession of an oval cryptocyst depression, perforated by a pore, the kenozooecium answers to the stem-joints in Clilulonia.
Together with the appertaining oa'cium the gonozooecium (3 a, ;{ h, 3 c) forms an elongated, rounded, somewhat compressed body, which is to a certain extent like a bean and the most arched part of which is turned away from the colony. The larger distal and more rounded half of this body is represented by the oa^cium, formed by two arciied, bilaniinar valves (3 h, 3 1), the free margins of which meet and enclose a wide, hollow space. If these two valves are opened out from each other (3 h) it will be seen that they cover the whole of the distal cryptocyst-bearing part of the gonozoa-cium, which latter dilTers from an ordinary zoa'cium in several respects. While the zoa-cium may most properly be called rather flattened, the gonozooecium is despite its strongly arched gymnocyst some- what compressed and seen from the side of a rounded, triangular outline (3 a, 3 k), with the two, somewhat outcurved sides of the triangle meeting in an acute angle pointing towards the kenozorecium. While in an ordinary zoa'cium the crypto- cyst-bearing part forms an obtuse angle with the proximal part consisting of the gymnocyst, this angle is almost a right angle in the gonozooecium (fig. 3 k). The aperture is a little larger than in an ordinary zocecium, and as the gonozocrcium seems to be quite symmetrical the two opesiula^ (fig. 3 e) are almost of the same size, and the above mentioned glistening stria on the proximal side of them is not inclined towards one side. The principal difference is however the ab.sence of the two horns, the space for which is occupied by the two ocecial valves. If these be removed a lengthy, oval opening is found on either side in the margin of the gonozo<rcium, and the margins of this opening are continued proximally and distally into the raised line surrounding the depressed frontal area. The distal pore-chamber ends in a small, round opening surrounded by a chitinized margin, and one of the cylindrical internodes mentioned on an earlier occasion may have had its place here.
205
An ooecial valve (figs. 3 n, 3 h, 3 i, 3 k) is a strongly arched, rather Ihin- walled, hilaminar structure, the two layers of which are joined in Ihe entire free margin of the valve. Its outline is like the one half of a transversely cut hean, and its straightly cut-off, proximal margin, which is in contact with the corre- sponding margin of the cryptocyst-bearing surface of the gonozooecium, forms on one side a right angle (towards the colony) and on the other side an obtuse angle with the curved line, that forms the further delimitation of the valve. The two valves are only connected with the gonozocecium in the periphery of the two elongated openings at its margin, and corresponding with the.se is a .similar opening in Ihe proximal margin of each valve. This connection is l)rought about by means of a slightly chitinized portion, which permits the valves to bend out- wards when the larvae are to be set free and appears on either side as a trans- versely oval, translucent spot, bounded proximally (towards the gonozooecium) by a slightly curved part of the separating ridge of the cryptocyst distally lo the lateral pore-chamber (fig. 3 k) and distally by a curved thickened part of the ooecial valve (the proximal arch <), which sends upwards two narrow, curved bells, originating from a partial fusion of the two layers of the valve. The inner surface of the valve also presents a chitinized portion proximally, which is bounded distally by a calcareous thickening connected with the just mentioned proximal arch. This thickening is placed lower, so that on examining the inner surface of the valve the basal arch will be seen projecting above it. The few younger stages (3 b, 3 k) I have found of such an ocecium show, thai the two ooecial valves begin as two small, rounded, widely separated plates, situated im- mediately above the elongated openings in the margin of the gonozoa^cium, and that it is only later that they meet at their margins and expand over the entire periphery of the cryptocyst-bearing surface. Such a very young stage of ooecium has also been figured by Busk.
It still remains to give a morphological explanation of this singular form of oeccium. As the gonozooecium has no horn-like spines, which appear in all the other zorecia, it is an obvious conclusion that the two hollow oa-cial valves may have arisen by a transformation of these spines, and in my preliminary state- ment ' I have taken this view of the matter. However the conclusion cannot stand a closer examination. Besides the distal pore-chamber, situated in the side of the gonozoa'cium turned away from the colony, the gonozoa-cium has further two elongated lateral pore-chambers (figs. 3 a, 3 k), situated immediately on the proxi- mal side of the place where the valves are attached, and the two elongated
' 56, p. Ui.
206
oponings in the margin of the gonozoo'ciuni lead directly into the two pore- chanihers, the inner wail of which has fi— 8 small, single-pored roselte-piales. As a spine is never separated from the appertaining zooeciuni hy any sophim furnished with rosette-plates, such heing only found on the houndary hetween two bryozoids (or in a terminal zoa-cium), we must set down llie two on'cial valves as kenozo(rcia, and the absence of the two spines is sufhciently explained by the fact, that the two valves leave absolutely no room for them. We have already on a former occasion called atlcnlion lo the fad thai a zoa-cium which is only connected with a single daughter-zoa-cium has only a single pore-cliami)er (3 c), and that the number of pore-chambers answers to the num})er of daughler-zooe- cia. The gonozott'cium with its oa'cium will accordingly correspond with a motlier- zooecium bearing two daughter-zoa'cia and otherwise as we shall see later on, three daughter-zooecia only occur on the lowest or the two lowest axial zocecia of the colony (3 a). The chitinous connection between the gonozo(i>cium and its two valves is also in accordance with what we know from the other indi- viduals of the colony.
The colonies form fine feathery tufts and take their origin from a system of branched, chitinous tubes covering various algse. Besides the oo-cia-bearing branches we may in a colony distinguish between zooecia of first, second and third order. The zoa?cia of the first order or the axial zooecia form a slightly bent zigzag row, and in every zooecium llie broad, cliitinizcd piece connecting it with the distally situated zooecium is alternately on the right or the left side of the longitudinal axis of the zoa'cium, on the same side as the larger opesiular opening. On the other side is the much narrower connecting belt with the obli- quely, distally directed zooecia of the second order, and from each of these two rows of zooecia of the third order may issue. In each row there may be from two to four zocjecia. The axial zoa-cia are longer than the others, tbc semi-ellipti- cal ridge more angular, the two opesiulae of less unequal size and the two horns less i)ointed and bent inwards a little. The principal difference in the zooecia of the second order and those of the third order is that the two horns of the former are bent inwards as in the axial zooecia. The lowest axial zodcium has most fre(piently a branch on either side, as is also the case now and then in the low- est but one. In a number of the lower axial zofpcia radical fibres proceed from the proximal half of the frontal surface.
Of this species I have been able to examine a large number of dry colonies from South Africa (Miss Jelly).
207
3rd Subdivision: Pseudostega.
The boundaries of the separate zowcia are not shown on the surface of the colony, which on the other hand is divided into a number of deepened areas, the number but not the extent of wliicii corresponds with (he separate zoa>cia. No pores or spines, hidependent aviciilaria without calcified transverse bar be- tween the opercular and the subopercular area. The ocrcia, situated in the distal part of each zotrcium, are inner spaces in the frontal wall of the zooecia and open outwards through a variously shaped opening.
Family Membranicellariidae n. f.
The zoa'cia have an oval aperture surrounded by a raised rim with onlv the distal part filled by a membranous opercular valve.
Membranicellaria (n. g.) dubia Busk.
? Melicerita dubia Busk, Challenger, Zoology, Vol. X, Part I, 1884,
pag. 97, PI. XXXIII, fig. 1().
(PI. VII, figs. 2 a— 2 e).
The surface of the colony is divided by distinct suture-like separating lines into broad depressed areas of a rhombic or hexagonally rhombic form (the two neighbouring areas sometimes only meeting in a lateral corner, sometimes in a shorter or longer edge) and in the greater part of their circumference they have a more or less distinctly bounded, rather narrow, thickened, prominent marginal part, which however most often disappears be^'ond the centre of the two proxi- mal separating lines. Each area has a large, oval aperture in the centre, the dis- tal margin of which is very slightly curved, and with the exception of this it is encircled by a pretty broad, projecting marginal portion. The entire surface of the cryptocyst is closely set with small round tubercles, which are most plentiful in the boundary ridges of the areas and in the marginal portion surrounding the aperture, and are arranged in more or less regular transverse rows. In the middle of the basal part of the distal wall a large, single-pored rosette-plate is seen, half surrounded by an arch-shaped collection of small, single-pored plates, and the distal half of each lateral wall has a similar group. The membrane covering the colony presents a system of linear, chitinous thickenings corresponding with the furrows between the separate areas, and a similar curved chitinous thickening separates the covering-membrane from the free margin of the opercular valve. The largei' opercular valve has a membranous frontal surface, but a well chiti- nized and strongly developed opercular arch and lastly, it may be mentioned
208
that the membrane covering the aperture has on either side towards the centre a parietal muscle attached to a very fine sclerite. Thai llie areas mentioned, which as it were imitate zod-cial surfaces, in reality are hounded by quite a superficial system of furrows and ridges is easily discovered when a layer of zooecia is isolated and the zotvcial basal walls are removed by grinding. Il will then a])pear (2 1)) Ihat the elongated, hexagonal zoa-cia are considerably longer and in the greater i)art of their length only about half as broad as the areas. The oval opening is situated in the distal part of each zo(i>cium and in the proxi- mal part of the frontal surface of each zotrcium three or four areas meet.
The ooecia, which have been overlooked by Busk, have been found in a number of zoo'cia in the fragment examined. Each ooecium is situated in the proximal part of a zoa*ciuin and may be considered as a part of its cavity, which has obtained a distal and an inner wall of its own. Its frontal wall is a part of that of the zooecium and this is also the case with (he proximal wall. The frontal wall is somewhat arched and marked by three, confluent boundary lines between three areas, the marginal ridges of which are a little thickened at this place and have large, closely placed tubercles. Immediately on the distal side of the opercular valve the three-lobed opening of the oa?cium appears. My mater- ial has not permitted me to investigate the development of these ooecia.
Avicularia were not found in the fragment examined; but according to the statement of Husk they occur in small numlier in the margin of the colony, and as far as we can judge from his figure the greater part of the subopercular area is uncalcified.
Of this species I have by the kindness of the Director of the British Museum been able to examine a small fragment of the original specimen of Busk.
To this family I must refer the following species described by d'Orbigny' from the French cretaceous formation, namely £^sc/iara Aces/e (PI. 662), E. Achates (PI. 662), E. Acts (PI. 662 & 676), E. Aega (PI. 66;^, E. Amatct (PI. 665), E. Ca- hipso (PI. 669), E. Cijmodoce (PI. 674), E. Dana- (PI. 675), Hiflustra rhnmbnidalis (PI. ()91), B. mccandrina (PI. (H)5), B. Elea (PI. 678) & B. echinata (PI. 69.")). In all these species occurring in free two-layered colonies, quadrangular or hexa- gonal rhombic areas are found arranged in transverse rows, with a larger or smaller, round or oval, generally central aperture, and the avicularia are as in Menibranicellaria dubid usually placed in the margins of the colony. Of the just mentioned species I have myself had the opportunity of examining E. Acis & E.
' 86.
209
Danw, in which there is a similar relation hctween areas and zocecia as in M. (labia. Ooecia appear to he found only in B. Elea & B. eclunala, and they are here more consjiicuous on the surface of the colony than in M. diibia. In the former they appear to have a trilohed opening like the one found in Busk's species. A fossil species, which may also with certainty be referred to this familj', is Bifliistra Prazaki Novak'. As the author gives not only a transverse section of a colony hut also figures the basal aspect of an isolated zoa'cial layer we here see a distinct contrast between the broad, rhombic areas and the long, narrow, hexagonal zocecia. Until a closer examination has settled the question whetlier these species sliould he referred to one or to several genera we suggest that they be all referred to the genus MetubranicclUui<i.
Family Cellulariidae' (non Hincks). Cellariidae Hincks. Salicornariadae Busk. (I'ls. VII .>;: VIII).
The whole frontal wall of the zocecia is a cryptocyst and they have a well chitinized, hilaminar, simple operculum with a straiglit or concave proximal margin. Within the jjroximal and sometimes also within the distal margin of the aperture is placed a pair of (or sometimes a single broad) supj)orting teeth.
The ou'cia are iiollow spaces in the thick frontal wall and arise by a resorp- tion of the latter, which they finally break through. The suhopercular area of the avicularia has an unusually strongly developed, sometimes almost complete cryptocyst. Tlie colonies are most frequently jointed with cylindrical internodes, more seldom two-layered lamina'.
The depressed, rhombic or hexagonal areas are not only separated by the raised borders, in which the more or less sharply ascending lateral parts meet, but also by the distinct furrows which run along the middle of these borders. The aperture sunounded by a somewhat projecting margin is most fretpiently situated in or proximally to the distal third of the area, more seldom in its centre, and it is most often furnished with a more or less convex, more rarely straiglit j)roxinial margin, which has generally sliort, rounded, conical, more seldom long and pointed teeth supporting the operculum. In a few cases a couple of similar teeth are also found in the distal margin of the aperture. The crypto- cyst is more or less tui)erculous and in a number of species (for instance in Cell, divaricala. Cell, diihid) it has within each area two long, curved, elevated
* 85, p. 94, T:if. Ill, fins. '20—25. ' As to tlic use of the- iuiiir- C.cllulniiidae sec- 83, p. 577—78.
U
210
ridges, which may sometimes meet in the dislal and proximal pari of Iho area. The operculum, which has usually a jji-oximaj, concave, more seldom straight margin, consists of an outer memhranous pari, continuous with the covering- membrane, and an inner chitinized part, which is connected with the cryptocyst and must be regarded as an uncalcilied part of the latter. This internal layer, Avhich may have a variable sculpture and to the free margin of which the oper- cular arch is attached, shows in the species with the short, rounded supporting- teeth a light, rounded spot on the inner surface towards each corner, which is the mark left by one of the teetli. Wliile the operculum is thus connected proxi- mally with the cryptocyst and covering-membrane of the frontal wall, it has moreover a peculiar, suspensory a|)paratus on each side. On either side of 11 namely the inner surface of the covering-membrane is furnished with a curved, linear, cliitinous thickening, a short lateral branch of which reaches as far as to the con-esponding corner of the operculum, joining the chitinous layer of the latter. The two distally as well as proximally convergent chitinous thickenings are separated in most species, but in Cell, magnified they meet distally as well as proximally, while in Cell, allanlica they meet only proximally. Lastly by a sj'slem of filiform chitinous thickenings the covering-membrane is divided into a number of areas corresponding to those of the cryptocyst, and Ihese lliieken- ings are situated in the separating furrows between the separate areas, l)eing here firmly connected with the cryptocyst below. Husk wrongly supposes this fila- mentary net to be hollow.
The ooecia are as in the preceding family hollow spaces hidden within the surface of the zooecia and opening outwards distally to the zoircial a|)erlure at the distal end of an area but in the proximal end of the zoa-cium. Their frontal wall is sometimes a little projecting sometimes a little depressed, and the outer opening may also be of a varying form, hi most cases it is however (ransver.sely oval with a low but broad, rounded or quadrangularly rounded j)rocess in the proximal margin (PI. VII, fig. 5 a, PI. VIII, figs. 2 a, 1 a). In Cell, /istiilosa the openings are however round at the distal end of a joint. The opening has a bilaminar operculum, which may be drawn into Ihe ocecium by means of muscles. These peculiar ooecia seem to arise by a resorption of the thick fronlal wall of the zooecia, and they begin with the formation of an extremely small cavity (PI. VII, fig. 4 f, PI. VIII, figs. 1 c, 2 b), gradually increasing in extent and ulti- mately opening outwards through the above-mentioned opening (PI. VII, fig. 4 a, PI. VIII, fig. 1 b), which is also formed gradually, Hie initial stage of it being a sma41 slit or pore. By means of a number of longitudinal grindings we maj' find these ooecial spaces in dilTerent degrees of development and when they have at-
211
laiiied a certain size their presence is already sliowii on leganliiig liie IVoiital surface of tlie respective zooecia, the latter then lieing half transparent. Pis. VII and VIII show dilTerent stages in development of such ooecla in Cell, aiistralis. Cell. ri<jiila and Cell, atlantica.
The avicularia, only occurring in small numbers, vary much botli in size and form, and the largest of them, the dimensions of which are similar to those of the zocccia, reach right to the axis of the colonj', while this is not the case with the smaller of them, the latter being only wedged in between the zooecia. Judging from the figures given by Busk in his account of the Bnjozon of the Challenger Expedition we should imagine that these avicularia had constantly a complete subopercular cryptocyst. But although the latter may be unusually strongly developed, it is only in exce[)tional cases and in older zooecia, e. g. in Cell, fistiilosa, that it reaches right up to the operculum. As a rule it has either one median or two symmetrical incisions dislally, and in Cell. iiKilviiiensi.s, which is in fact one of the species figured by Busk, the median incision is separated from the opercular area by a tiny cryplocj'st arch, which unites the two inner ends of the suspensory facets of the mandible.
The very peculiar fact, that the areas perceptible on the surface of the colony are by no means ecpud in size and extent to the zooecia, has hitherto escajied notice, and Busk's description of the separate superficial divisions as »areas is in accordance with his incorrect conce[)tion of the above mentioned liliform chi- tinous thickenings as a system of hollow lilamenls shared in common by the whole colony, imbedded in and effecting the growth and the calcification of the separating walls, which he imagines to exist between the separate areas. There can however be no doubt that Busk thinks every area to correspond with a zoa'cium (»Zoa^cia completely immersed, each corresponding to an area '). That the areas and the zooecia do not correspond in this family is most easily seen on isolating a single zoo3cial layer of Cell. (ilUuitiai and grinding away the basal wall (fig. 2 c), as the narrow eloiigated zocrcia and the much shorter and broader rhombic areas may then be seen at the same time. In regarding a longitudinal grinding it will also be very obvious that the orecia, the bottom of which is a part of the separating wall between two zoircia lying in the same longitudinal row, open in the distal part of an area but in the proximal part of a zocxcium (PI. VIII, figs. 1 a, 1 I), PI. VII, fig. 4 f).
We may now by means of longitudinal and transverse sections make a closer inspection of the way in which the separate zotrcia are mutually connected in
' 8, p. 83.
14*
212
a cylindrical segment. In Iho cavity of every zooecium we may distinguish be- tween a narrower proximal and a much wider distal part, curving outwards to the surface under a right or an obtuse angle (Fl. VII, figs. 4 a, 4 f , PI. VIII, ligs. 1 b, 1 c, 2 b). While the distal broader part, wliich bears the aperture, readies the axis of the colony, the case is dillerenl with Ihe narrower pari whieli only reaches the frontal end of a separating wall, that separates the broad ends of two zocpcia for a short distance, but these two zoo'cia are not situated in two adjoining longitudinal rows, but in two longitudinal rows separated by a third. The narrow proximal part of a zoacium, which has a triangular trans- verse section (PI. VII, figs. 4 b, 4 c) and is closed proximally by the pari of the distal wall, which is furnished with rosette plates, does not join the corresponding part of another zoa^cium but the broad part of the zotrcia in the two neighbouring rows, with which it is connected by a multiporous, in these zocecia inwardly arched rosette-plate. Each zorecium has thus on either side two multiporous rosette-[)lates, one arching inwards in the broad i)ait, and one arching outwards in the narrow part. As a transverse section shows, the broad part of a zooecium is nearest the axis separated by a separating wall from the broad part of another zooecium, further outwards from the narrow part of a neighbouring zooecium, and nearest the frontal side from the ooecium of the same zooecium. A longitudinal section of a joint has a dilTerent ai)pearance according to whether it is cut right through the axis or beside it, as in the latter case we may see not only the cavities of the two zooecia, which have been mostly aflected by the sections, but also a number of smaller cavities which have ari.sen by the intersection of the stellate, adjoining separating walls and lead into a number of intermediate zo(ccia. This may easily be seen on imagining a section carried through fig. 4 c on PI. VII. Time has not permitted me to enter thoroughly into the classification of this family. It may however be reasonable to suppose llial the large genus Celliilaria may naturally be divided into several, possibly accord- ing to ditTerences partly in the chitinous ridges surrounding the aperture partly in the tooth-like processes of the latter. A generic division based only on the difference in form of colony, on the other hand, I cannot acknowledge as natural. Of the .species described in the work of d'Orbigny mentioned above the following may, I lliiuk, be referred to this family: Ksclutid Biva (PI. (Jti.S), E. Artemis (PI. 667), Escharinella elcijdns (PI. ()8I5), Esclutrella Anjus (PI. 666), Escluiri- fora rhomhoidalis (PI. 684) and E. crassu (PI. ()(S4), of which the three last named in contrast to the other members of this family have a smaller iunni)er of large pores surrounded by a raised margin. While none of these figures show any teeth in the aperture, the latter according to Waters is in E. Argus furnished with
213
two distal and two proximal teeth as in Cellnlarki rigida and several other spe- cies. In E. rhomboidalis and E. eletjans the structure of the ooecia seems to be similar to that in Celliilaria.
Suborder Ascophora.
A compensation-sac occurs, which most often opens out immediately on the proximal side of the operculum, more rarely further hack through a median pore (an ascopore). The operculum is generally a compound one more or less strongly chitinized, consisting of a distal valvular part bounded by the hinge-line and opening outwards, and of a proximal part opening inwards, which may be looked upon as the operculum of the compensation-sac. More rarely a simple operculum is found the proximal margin of which coincides with the hinge-line, and in that case the compensation-sac opens out through a median pore. The hetero- zooecia have as a rule a calcified transverse bar between the opercular area and the subopercular area.
Family Catenariidae ' nov. nomen.
Catenicellidae auct.
(Pis. X-XIII, IMs. XX, XXI, XXIII).
The frontal surface consisting of a gymnocyst has either a semi-circle of larger or smaller fenestra; (most often 5 — 7) or a number of scattered, larger or
' 111 our of Ihu platos (Pulypes, PI. l.'i) ;icci)m|);iii\ iiif^ tliL' fireat work on Egypt S ;i v i g n y wlio did not siicct'cil ill describing the Brijozoa, of which lie lias given so excellent figures, has at the hottoin of tlie plate designated two species in the plate luimbered as 1 and 2, as »Catenaires" and as lie always ill his plates designates the genera with a Kiench name in the plural form very similar to the Latin generic name (,e. g. Kuphrosynes := Euphrosi/nc, I'olynocs = Polynoe, Terehelles = Terehella. Gemellaries = Gemellaria, Chlidonies = Chlidonia) there cannot be the least doubt that the French name »Catenaires'i corresponds to a Latin generic name Catenaria. Audouin, who has given iiaincs to Savigny's species, without regard to the generic name given bySavigny, refers the two spe- cies to the genus Eiuralca and names tlrc-m E. Conlci and E. Lafontii. To this genus however, they do not belong. In Manuel d'Actinologie p. 4(!'2 li 1 a i n v i 1 1 e admits that Savigny has established a genus Ciilriuiriii, but without justification iinidilies the name to Catenicella, and to this genus he refers (kilciuiriK Conlci, the name of which he changes to ('., Saingni/i. The definition Blainville gives of the genus Catenicella is partly made from Savigny's figures of C. Contei partly fnnii Ilipjiollioii ilii'diirdfa which lie thinks is jierhaps identical with C. Contei, and Blainville ha,s thus cuinpktely misumlerstood the genus to which bis name has ever since been associated. D'Orbigny has laUr iiislitiiled a genus Catenaria in which he placed C. Lufonli. I propose to keep the genus Cdlrniiriii Sa\igiiy with the type-species f.'. Contei, but whether .Savigny's name is acknowledged or not, H 1 a i 11 V i I 1 e' s name cannot in any case be maintained. If Savigny is acknowledged as author of the genus Ciiteniiria then the name Catenicella is only a synonym and if not, it is in my opinion absolutely contrary to good sense that iJ I a i n v i 1 1 e ' s name should be associated with a genus which lie lias not only completely misunderstood but of which be has not seen any species. In that case the genus must be named Vittaticella Maplestoue,
214
smaller, sonielimes extremely smiill nores. A ervptocvst may be I'oimil pailly in the shape of a senii-cireiilai- or semi-elliptical calcareous lamina, which from the proximal margin of the primary aperture extends some way down the inner sur- face of the frontal area, partly within the above mentioned fenestra'. No mar- i;inal spines but sdmelinu-s sluul. aeropelalous, adoral spines and more or less developed bilaminale spines. The aperture has a more or less strongly ehilinized comiiound operculum, and the distal wall, consisting of a horizontal basal and an obli(piely asciMiding frontal part, as well as the lateral walls, have a larger or smaller luimber o! small, scattered, single-pored rosette-plates. Tlie znaria are conneeled with a nundier of lalcial cliaiiihcrs. uh)sI often keno/oo'cia, fretpuMitly to a certain extent uncalcilied, Ihe ty])ical nund)ei' of which is four on each side. The second chand)er (reckoned from the distal end of the zo(vcium) is however in a greater or snuiUer luuuber of /.oo>cia develoited into an aviciilnriniii. The o<vci(t, usually situated on gonozocccia of nuire or less ])ei'uliar structure, are endozo(vcial and nuiy be covered either by ordinary zoiecia or by kenozoircia.
The free, highly branched colonies fui-nished with radical libies, the zoiecia of which are all turned in the same direction, are jointed, consisting of internodes which may contain 1 — ',\ zoa'cia. Most freijucnlly internodes with one and inter- nodes with two zo(\'cia appear in the same colony, alternating in dilVerenl ways.
The nmsl peculiar charactei- in this very natural and very distinctly delined family is the presence of the above mentioned lateral chambers. Waters' has I'alK'd the one, which in a greatei- or smaller number of zoo'cia is devel- oped into an axicularium, the avicularian chamber* and the two contiguous ones the »supra-aYicularian« and the inlVn-avieularian chamber . while he calls the proximal one, which is independent of Ihe aviculariuiu, the jietlal ehamher<^. However the name of avicularian chamber cannot very well be applied as a spe- cial denomination of the above mentioned chamber, as it must he used in Ihe ordinary sense of Ihe word. i. e. as the name of the chandier in all avicularia, nor can it properly be applied with respect to the zo(vcia in which this cluuuber is not develo])ed into an avicularium. For this reason I propose to call these three chambers the ^-scapular', the supra-scapular- and the "infra-scapular* chambers. Each lateral wall of a zoo'cium in eonneclion with the lateral chambers mentioned has generally two separate groups of roselte-jtlates, a distal and a proximal, the number of jilates in which most frequently varies between 10 and 4 but sometimes may be only one. hi the genus Hiiuhsivlld the proxinud group is wanting and the distal one represented by 1 — 2 rosette-plates, hi the species of
' 107. p HX
215
tlie genus Clauijxnclld the inoxiinal one is also icprcsenk'd by a single rosette- plalc. While the proximal group serves as a conimunicalion with the pedal chanihcr llic distal group serves either as conimunicalion with the sca[)ular chamber only as in Sciilirclla plfifiioslonid, Sr. inlcrinedid, Sr. venlricosa, Cal. niiir(/(iriltii('ii, or as conimunicaliDn with Ihe inlVa-scaiiular ciiambei' as well, e. g. Sc. (implwra, Sc. laiira, Sc. Wilsoiii and the species ol' the genus (Idli-narid. If the scapular chamber is developed into ;in avicularium, its rool' or distal wall (Pi. XI. figs. 1 c, 3 b, ;j e, 4 b) is luiiiished with a number ol' rosette-plates forming a communication with the supra-scapular chamber, while the proximal wall fur- nished in the same way (IM. XI, figs. 1 e, 2 b, .'{ a, 7 b) makes a se|)tum for the infra-scapular cluMuber, which, as slated above, in a series of species may also be in direct communication with the zoo'cium. If on the other hand the scapular chamber has not attained this degree of (levelo|)inenl it will coalesce with or be only incompletely separated from the adjacent chambers. While as a rule there will be no difficulty in distinguishing the various lateral chambers belonging to the solilaiy zoci'cia oi' those belonging to the outer (abzocccial) sides of the bi- zoo'cial ailiculale parts, il may be more diflicult to identify several of the lateral chambers belonging to the inner (adzocecial) sides of the two zoo'cia in a bi- zooecial segment. Moreover these two zoa-cia are not of etpial value, as we must distinguish between a motlier-zoo'cium springing fiom the pioxiinaily situated segment, and a daughter-zou-cium without communication w'ith the segment but issuing from the mother-zod-cium.
If Ihe adzoa'cial side of the daughter-zooecium is furnished with an avicula- rium, its three distal lateral spaces will always be clearly developed, e. g. in Costicella Imstata (IM. XX, fig. Mb), Ptcmcella alula (PI. XXI, fig. 4a;, Calenaria elefjans (PI. XXI, fig. 2 a) and (>//. j'oriiiosa (PI. XXI, fig. 3 a), whereas its j)edal lateral chamber (d. IV; is usually wanting. It is however pre.seiil in all the spec- ies of the genera Coslicrlhi and (Mlenaria, in Slrojihijiord lldivnji as well as in Sciilicelld sdcciildld, Husk and .Sc. /'/•(V/iV/ri, Waters' which two species may be regarded as transitional forms between the genera Sculicella and (jiteiidria. Al- though the daughter-zooecium itself has lateral chambers it still takes the same place in relalion to the mollur-zoo'cium as the scapular eliambcr in a solitary zoa-cium, being in communication with the mother-zoo'cium through the group of rosette-plates described above as the distal, and the adzoiecial, distal lateral chamber of the mother- zotrcium which communicates with the daughter- zooecium through a group of rosette-plates, must accordingly be explained as the
' 115, pi 1, fig 1 a.
216
adzofrcial, supra-scnpiilar (m. I) laU-ral clianiber of the molher-zoa>ciiini. This is clearly seen e. g. in Scnticclla iiidciiUild (PI. XX, fig. 5 b), in which species Ihis chamber lies opposite the corresponding abzoa-cial, supra-scapnlar lateral chamber, from which il is only sej)arated by a short raised line. Although the daughter- zo(rcium, as said before, may be considered the adzooecial, scapnlar chamber of the mother-zod'cium, and we cannot for this reason expect to find an avicularium on the adzon^cial side of the mother-zooecium, the species of the genus Pterovdla (PI. XXI, fig. 4 a) make an exception lo the rule, a small adzooecial avicularium being always jiresent. The adzooecial, pedal chamber of Ihe mother-zoo-ciuni (m. IV), whicii is always developed, is not difficult to find, and il then only remains to determine the adzotrcial, infra-scapular chamber of tiie molher-zofi'- cium (m. III). We have seen that an infra-scapular chamber is only independently developed in such zoo-cia as are furnished with an avicularium wilh which they communicate through the proximal wall of the latter, but that in a series of s[)e- cies it also communicates wilh the zoo-cium itself through some of the rosette- plates in the distal grouj). In accordance wilh our conception of the daughter- zooecium as being the scapular chamber of Ihe molher-zoa-cium, we must consider the only lateral chamber that we have not yet explained as the adzoa^cial, infra- scapular chamber of the mother-zotrcium. It is in most cases a very small, oval or pear-shaped, sometimes almost slit-like space, situated almost in the middle of the boundary line between Ihe two zoo'cia of the segment, and rarely allain- ing any considerable size. Its extent is largest in Strophiiuini lldrrfiji (PI. XXI, fig. (i a), in which besides extending a little into the dnugbler-zott'cium il also occuj)ies half Ihe frontal surface of the molher-zoa-cium. In Sciilicclla Wilsoni it also attains a considerable size, filling as il does the greater part of the deep dej)ression between the sternal areas of the molher-zocEcium and the daughler- zooecium. In the species of the genus CdleiKtria this boundary chamber has like the ordinary infrascapular chamber a doui)le inner communication (through ro- sette-plates), viz. both with the daughter-zou'cium and with the molher-zoa>cium, while the corresponding chamber in Sciiticella species only communicates with Ihe mother-zoopcium. A similar dilTerence, as already mentioned, is found within the genus Scdticella, all Ihe roselle-plates of the distal group serving in .some species as a communication wilh the scapular chamber, while in others some of them form a communication wilh Ihe infrascapular one. ^^'itll respect lo Ihe above chamber we must still notice that il generally occurs somewhat incon- stantly within the genus, in Scuticelht mdrtjdrildcea for instance it is absent, while it is present in the form described in Ihis work under the name of <SV. mar- (jaritaced, var. connedens (PI. XX, fig. 3 b), but which perhaps ought to be con-
217
sidered a separate, though very closely allied species, hi the genus Catenaria it seems to be constant.
We have already observed (pag. 215), that a more or less complete coales- cence of the three distal lateral chambers into a single, wholly or partly mem- branous chamber takes place in all the cases in which an avicularium has not been developed. Hut in addition, the adzooecial, pedal chamber of the daughter- zoa'cium may fuse with the adzoa'cial, infra-scapular chamber of the mother- zoa'cium in the bizoa'cial segment in several Catenaria species, e. g. in Cat. Biiski and Cat. fii.sca.
As Mac Ciillivray in the genus Sciilicclld speaks of an cpithecas which is generally understood to be a membranous covering over a cryptocyst, I must ex- pressly emphasize, that in this family a cryptocyst only occurs in the form either of the above mentioned, inner calcareous lamina or as an incomplete fdling of the fenestrse of the sternal area. In a series of forms a large part of the surface of the zooccium is indeed covered by a membrane; but in these cases it is the uncalcified external wall of the peculiar lateral chambers, which may in some cases cover the whole of the zocrcial surface, and it might be as justifiable to call the membranous frontal wall in a Fliistra an epitheca in relation to the calcified basal surface. In ail other cases a membrane is completely absent on the calcified surface of the zod'cium. These lateral chambers attain their greatest extent in Struj)hiiiura Ihuvciji (PI. XXI, ligs. (5 a — 6 f), in which they cover nearly the entire surface of the zoa'cium and are only separated by narrow calcareous ridges. They also reach a considerable development in Sciiticella Wilsoni (PI. XI, figs. 2 a— 2 c, PI. XX, ligs. 2 a— 2 b) in Sc. amphora (PI. XI, figs. 3 a— 3 c), Sc. iirniila (PI. XX, figs. 1 a — 1 c, PI. XI, figs. 4 a — 4 b), Calpidiiiin ornalam (PI. XX, figs. 11 a — 11 f) and Cat. ponderosiim (PI. XXI, figs. 5 a — 5 f), in which species they chiefly cover the greater part or the whole of the basal surface. In Sc. Wilsoni (PI. XI, figs. 2 a— 2 c, PI. XX, figs. 2 a 2 b) the greater part of the frontal surface is formed by the infr^-scapular lateral chambers and the entire basal surface by the supra-scapular and the pedal, while the greater part of the basal surface in Sc. amphora (PI. XI, figs. 3 a — .'5 b) is formed by the supra-scapular and the pedal and in .Sc. urniila (PI. XI, figs. 4 a — 4 b) by the supra-scapular, the infra-scapular and the pedal chambers.
Finally, it must still be remarked that the gonozooecia as well as the keno- zooecia covering the oa'cia may have lateral chambers in varying number and developed to a varying extent, and on the whole these chambers must be said to be of great systematic importance.
While in a smaller number of the species of this family a distinct sinus is
'218
found in the proximal part of the aperture, e. g. in Hincksielhi pnlchella (PI. XII, fig. 9 a), Sculicellu maryarildced (PI. XX, iigs. 3 a — ;}1), Sc. nentricasa, var., Crihri- celln riifd (PI. XII, figs. 7 e, 7 f), the species of the genus Calj)idiiim (PI. XX, fig. 11a) etc., a much larger lunnher show more or less distinclly, llial such a sinus, which I propose to call the ^sternal sinus<, must have heen present al an earlici- stage hut has later on become wholly or partly filled by outgrowths from llie margins of this sinus. It seems in fact that the species of the genus Calciutriii and Slrophipora Hnrveiii are the only ones that show no traces of such a sternal sinus, while the most indislincl traces arc found in the genus Sculicellu, most species of which show a short sutural line in the middle of the proximal margin of the aperture (PI. XX, figs. 4 a, 5 a, 5 b), arisen by a concrescence of two short ribs which have filled the sinus, a very small remnant of the latter being gener- ally seen in the form of a little perforation behind the suture. If Ibe two ribs are somewhat projecting, the original extent of the sternal sinus is clearly seen, as e. g. in Scnlicella Wilsoni (PI. XX, fig. 2 a). The vestige of this sinus is much more distinct in Sc. iinuila (PI. XX, fig. 1 a) and Pterocclla alaUi (PI. XX, fig. 4 a), in whicli it is filled by two larger distal and two or three smaller, almost tu- bercle-like proximal ribs. While the sinus in the Cdlpitliiiiu species (PI. XX, fig. 11a) is filled by the proximal part of the compound oi)erculum, so also in Clavi- porclla (PI. XII, figs. 3 a— ;ib, PI. XX, figs. 10 a— 10 b) the proximal part of the operculum takes pari in Idling it, but at the same time the proximal part of the very deep, j)rimary sternal sinus is cut olT, in the shape of an oval or slit-like opening, from the part filled by the opercular tongue by two ribs meeting in a sutural line, which in CI. aiirila show a distinct internal hollow. In the genus Cuslicdla the sternal sinus not only attains its maximum size, but the ribs filling it appear in larger numlicr, separated by transverse fissures and showing a dis- tincl internal hollow, which is but rarely seen in the short rudimentary ribs, found in the majority of the species of this family. Thus in Scnlicella Sdcciilala (PI. XII, fig. 2 a) a distinct internal hollow is found in the two lateral ribs.
To understand the structure of the ribs or spines, which wholly or partly fill the sternal sinus, we must bear in mind that the above mentioned, inteinal, rounded calcareous lamina, which may I think justifiably be defined as a cry|)to- cyst lamina although it is covered by a gymnocyst, starts from the proxinuil margin of the primary aperture at a time when this has not yet become calci- fied, and as the sternal sinus forms indeed a larger or smaller pail of this margin, this cryptocyst lamina must consequently in a greater or smaller extent be said lo sj)ring from the margin of the sinus. In this way it sj)rings wholly or partly from the sternal sinus in the species of the genus Coslicella, while this sinus
219
only to a slight extent takes part in its I'oiniation in most species of the genus Sciiticell<i. When the cryptocyst lamina expands on the inner surface of the frontal wall the rihs grow at the same time from the hilaminar, uncalcified marginal portion, in which the cryptocyst and the gynuiocyst meet, and they must there- fore themselves be considered ])ilaminar, although the two layers in most cases will he coalesced into one solid rib. In some cases e. g. in Scuticelln maryaritacea, var. conneclens (PI. XX, figs. 3 b, 3 c) these spines, between which there is left a part of the original sinus, remain uncalcified at the end, and this may be seen most plainly in the gonozooeciuni.
While the a})ove mentioned cryptocyst lamina is originally only continuous with the margin of the primary aperture and is otherwise free (PI. XI, fig. 1 n cpl.), it gradually with growth coalesces with the inner surface of the frontal wall to a varying extent and in diiTerent ways; it is for instance distinctly seen in Costi- celld lidsldla (PI. XII, figs. 1 a--l d. see explanation of plates) that the hollow in the quadrangular, plate-like spines rising from the sternal sinus, is continued bej'ond their starling point uj) to the round fenestrsc in the .sternal area. The fact is that the regions, separating these hollow spaces from each other, are formed by a fusion or soldering of the cryptocyst lamina with the inner surface of the gymnocyst.
With the exception of a few species (Cnlindiiim ornatiim, Piemcella (jemelki) in which every internode consists of two or three zooecia, we find in the others internodes with one and internodes with two zorecia alternating more or less regularly with each other, but we may in this respect distinguish between two cases, which do not however show any important differences, as both may appear within the same genus. In one case a bizocrcial internode always takes its origin from a unizoa^cial one, while here and there a series of successive single zonccia may spring from the daughter-zoa^cium of a bizooecial joint. This is the case e. g. in SciiticcUa j)hi(jlstnnut, Sc. intermedin, Sc. loiica, Sc. Wilsani, Sc. amphora, Sc. iiKiciildla, Cribricclla riifa,Crib. crihraria, Cateiuiria pcrj'ornla. Cat. elegans and Cat. formosa. In the other case one bizooecial segment may on the contrary often follow another, which may be repeated at least three times, while at the same time an alternation of uni- and bizooecial internodes may be seen in the neighbour- ing branches. This may be seen in Scnticella ventricosa, Sc. margaritacca, Ptero- cella alata, CUwiporelln gemiimta, Catenaria Buski, Cat. fiisca. Cat. taiiriiia and Stropliipora Harueyi.
2 'in
Synopsis of the genera.
1) The inner surface of the frontal wall with a rounded cryplocyst lamina (issuing from the proximal margin of the primary aperture), the free margin of which is most often dislinctly visihle through the frontal surface, esjjecially through its fenestrie:
2) The hinge-teeth slightly developed and indistinct:
3) The frontal surface with numerous, scattered pores; llu' inner calcareous lamina short and broad and only seen distinctly from the
inner surface of the frontal wall Cribricella n. g.
3) The frontal surface with from three to twenty odd (more rarely only a single) larger or smaller fenestra' or pores disposed in a con- tinuous curve or in an angle; sometimes within the area bounded bj' the fenestrje transverse fissures more or less regularly arranged in j)airs; the free margin of the internal calcareous lamina generallj' clearly vis- ible through the fenestrse.
4) Within tlie area bounded by the fenestrse a larger or smaller number of transverse fissures separating more or less developed, gener- ally hollow spines.
The lateral chambers wholly or almost wholly calcified; the ad- zooecial, scapular chanii)er of the daughter-zooeciuni developed into an avicularium Costicella n. g.
4) No transverse fissures found within the fenestrse; at most 2 — 5 rudimentary spines on the proximal side of the aperture; lateral cham- bers mostly membranous: the scapular chamber on the adzoa'cial side of
the daughter-zocecium not developed into an avicularium Scuticellu n. g.
2) Strongly developed hinge-teeth in the shajjc of robust, conical or cylindrical processes, generally freely projecting within the aperture:
5) The zooecia with 2 — 4 cylindrical, acropclal sj)ines distally, and a rudimentary circular pedal chaml)er proximally; the aperture with a
deep, rounded sinus Claviporella Mac Gillivray.
5) No cylindrical acropetal spines:
6) The aperture, not surrounded by a protruding margin; the four lateral chambers forming on each side a continuous, wing-like mar- ginal portion in the whole length of the zoaxium; the adzcxrcial side
of the mother-zooecium with an avicularium Ptcrncellii n. g.
6) The aperture surrounded by an acutely protruding sometimes bilobate margin; the lateral chambers forming no wing-like marginal
221
portion (the adzooecial si(U' of Hie mother-zooecium witliout an avi-
cularium) Calpidiiim Busk.
1) No inner calcareous lamina within the frontal wall:
7) The lateral chambers occupying only a small part of the surface of the zooecium; no longitudinal ridges dividing the frontal surface of the zott'cium into two lateral halves:
8) The frontal surface with a circle of small round fenestra, and the zou'cium with a wing-like, protruding marginal portion on each side in the whole of its length; this marginal portion formed only by the supra-scapular and the scapular chambers, the latter of which is devel- oped into an avicularium; hinge-teeth slightly developed and not protruding into the aperture; the latter furnished with a well devel- oped sinus Hincksiella n. g.
8) The frontal surface furnished at most with extremely fine, scat- tered pores; no wing-like marginal expansions; the pedal lateral cham- ber very oblong, narrow, sometimes linear; hinge-teeth strongly devel- oped, freely protruding into the opening; the latter has a concave proximal somewhat protruding margin; the aperture is ultimately closed by three calcareous processes issuing from the inner margin
and meeting in the centre Catenaria Savigny.
(Vittaticella Maplest.).
7) The lateral chambers occupying nearly the entire surface of the zooecium and on the frontal surface only separated by a narrow, longitudinal ridge, divided into two by a furrow; this ridge has an annular expansion, perforated by a pore, on the proximal side of the aperture Strophipora Mac Gillivraj'.
Scuticella n. g , ((^alenicella auct.)
The sternal area has 3 — 14 (in a single species only one) fencstroe or pores, disposed in a curve or an angle, and on its inner surface a rounded calcareous lamina springing from the proximal margin of the aperture. The hinge-teeth are rudimentary or indistinct and never freely protruding into the aperture, the proximal margin of which may be straight, concave or convex, sometimes with a small sinus or indentation, to which however the operculum never corresponds. The lateral chambers are wholly or mostly membranous, and the adzoo'cial, sca- l)ular chamber of the daughter-zocEcium is never developed into an aiucalariurn. In the old zoa-cia the aperture is not only closed by a calcareous lamina spring-
222
ing from ils inner margin, l)ul a calcareous expansion is also formed under the sternal area, which joins the calcareous lamina that closes the aperture.
Of the numerous species of this genus we shall here only descrihe a few, making one of them, Sciilicella phiyioslonui, the ohject of a more detailed de- scription.
Scuticella plagiostoma Busk.
Catenicella plagiostoma Busk, Voyage of Rattlesnake, pag. 358, Catalogue
of Marine Polyzoa, Cheilostomata, pag. 8, PI. V, figs. 1, 2.
(PI. \I, rigs. 1 :i-l I)).
The asymmetrical, angularly oval zooecia have an ohlicpie aperture, the length of which is ahout one-third of the whole length of the zoa'cium and its anter is almost semi-elliptical. From the two indistinct hinge-teeth the lateral margins hend outwards, converging again proximally, and the aperture is hy this means provided with a short proximal expansion, which has a slightly convex margin forming an obtuse angle with the one and an acute angle with the other lateral margin of the aperture. The slightly chitinized operculum, surrounded by a more chitinized marginal portion, does not fill the lateral parts of the proximal expansion of the aperture and somewhat decreases in breadth from the hinge-line towards the j)roximal end.
The sternal area, occupying the greater part of the frontal surface, has 5 large, generally pear-shaped fenestra- covered by a membrane. They are separated by narrow ribs, which meet in the centre of the zocecium in an oblong sternal portion. This often shows more or less distinct sulural lines as sign of the fusion and such a faint sulural line, ending in a fine pore, is seen almost vertically on the proximal margin of the aperture and a little closer to the acute-angled corner. It is due to the fusion of the two extremely small ribs, that fill the extremely small sternal sinus. Inside the inner half of the fenestra; we find the marginal portion of the oblique, semi-elliptical, cryplocyst lamina, which springs from the proximal margin of the aperture and originally hangs freely down on the inner surface of the sternal area (fig. 1 n, c. pi.). In lime however it coalesces partly with the sternal jibs and partly with that cryptocyst, which gradually closes the outer part of the fenestra-. The distal wall (fig. 1 n, dw.) is composed of a basal, horizontal and a frontal, obliquely ascending part, of which the former is pro- vided with numerous (up to 60) small, uniporous rosetle-plales, disposed in a horseshoe-shaped group with the opening towards the frontal side of the zocrcium. The ascending part is distinctly visible through the operculum at the distal end of the aperture.
223
Each lateral wall is divided into two planes, bent towards each other at an angle (figs., 1 f, 1 g), and, excepting the one that separates the niother-zooecium from the daughter-zocccinm in the bizooccial segment and which has in its proxi- mal part more than 30 uniporous rosette-plates, each of these planes has to- wards its centre a small group of 4 — 10 rosette-plates. Through the proximal of these groups the zooecium directly communicates with the pedal chamber, and through the distal one either with the scapular chamber only or with the infra- scapular one as well, which is in many cases either not at all or only incom- pletely separated from the former. The scapular chamber is generally developed as an aviculaiium on both sides of the zoceciuni succeeding the mother-zoojcium of the bizod'cial segment (fig. 1 a), and on the external side of the solitary zooe- cium or zo(x;cia springing from the daughter-zooecium of the same .segment. If a series of (up to 4) zoa^cia starts from the latter, one or several of them is often provided with avicularia on either side; but only in very rare cases do we find an avicularium on a bizooecial segment. The two avicularia occurring on the same zoa'cium are generally of different size. This difference is however largest in the zocrciimi springing from the mother-zod'cium of the bizoa'cial segment, as the avicularium situated on the same side as the acute-angled corner of the opening may be three times the length of the other. The avicularia, the ojier- cular area of which has a strongly developed cryptocyst, have an angularly rounded roof, rising outwards into a more or less steeply ascending, rounded and pointed terminal part which in the large avicularium is very long and proxi- mally to the distal point is furnished with a short hook. The roof of each avi- cularian chamber is provided with 4 — 10 rosette-plates, which serve for commun- ication between the avicularium and the supra-scapular chamber. The latter has only meml)ranous outer walls, formed bj' two outwardly ascending mem- branes, which meet at an acute angle and are separated from the avicularium only by a low, arch-shaped calcareous ridge on each side. The large avicularium, of the length of the zoa^ciuni, has its aperture turned obliiiuely towards the frontal surface of the colony, while the aperture of the small avicularium is turned in the opposite direction. While the large avicularium takes up the entire distal plane the snuill one occupies only the distal half of the latter, but in such a way thai all the rosette-plates are situated within its margin, whereas the proximal wall of the avicularium forming the boundary towards the infra-scapular chamber has 4 — (5 rosette-plates (fig. 1 d). Ajjart from the low, ridge-like calcareous walls, which partly surround and i)artly separate them from each other, the infra-scapular as well as the pedal chamber are only covered by a membrane. But while the infra-scapular chamber corresponding to the small avicularium
224
is situated immediately on Ihe proximal side of tlie latter, the one corresponding to the large avicularium is placed basally to its proximal part (fig. J h), and a similar tiiougli not always as obvious a displacement ol' liiis lateral chamber may also be seen in a greater or smaller number of the single zooecia, which may follow the daughter-zocvcium of the bizoa'cial segment. With exception of the above mentioned case the scapular clramber of the other zoa-cia is generally more or less incompletely calcified, and the calcareous walls, separating the com- l)lete avicularium from the supra-scapular and tlie infra-scapular chambers, are either altogether wanting or but incompletely developed. This cliamber is gener- ally least developed on the inner side of the zoa'cium (fig. 1 g) immediately suc- ceeding the often mentioned daughter-zowcium. It is here mostly membranous and ditfers from the pedal chamber in one thing only, viz. that the surrounding marginal ridge in its frontal part terminates generally in a more or less devel- oped spear-shaped process. In all the otlier cases (figs. 1 f, 1 e, 1 i), where this lateral chamber is not developed as an avicularium, its distal and frontal walls are membranous and only the lateral walls are calcified to a greater or lesser extent in dilTerent zoa^cia, forming thus two, as a rule triangular calcareous la- minae connected with each other under an outwardly directed angle.
While, in this species, it is not difficult to decide the position of the various lateral chambers in the solitary zocrcia, the case is a little more complicated with respect to the bizooecial segment, as the daughter-zoa-cium, which has lateral cliambers of its own, must according to its position be regarded as the adzooecial, scapular chamber of the mother-zoa^cium. As regards the two abzoa-cial lateral walls, of which one belongs to the mother-zocrcium the other to the daughter- zocccium, there can be no doubt, that the distal cavity corresponds to the three first, here unseparated lateral chambers, while the proximal one is the pedal. There then remain two lateral chambers, which are at the same time bounded by the mother- and the daughter-zocccium (fig. 1 b), a distal one, mostly bounded by the distal part of the adzo(Ccial lateral wall of the daughler-zotrcium, which has about 8 rosette-plates, and a proximal one, mostly bounded by the proximal part of the adzocecial lateral wall of the mother-zocecium, which is provided with G— 7 rosette-plates, and only to some extent by the proximal, truncated end of the daughter-zoa^cium. The distal chamber, the frontal wall of which is parti- ally calcified and thus forms a triangular or rounded triangular calcareous lamina beside the aperture of the daughter-zoa>cium, is in exactly the same relation to the daughter-zocccium as the supra-scapular chamber is to the avicularium and must accordingly be regarded as the supra-scapular chamber of the mother-zoa'- cium. The jiroximal of the two cavities may with as much certainty be con-
sklered the pedal, adzocvcial chamber ol' the iiiolher-zooeciuiii, being situaled on [he proximal surface of Ihe respective lateral wall, through the rosette-plates of which it is in direct comnuinication with the zod'cium. The infra-scapular cham- ber of the mother-zooecium is wanting.
At a certain age an occlusion of the aperture gradually takes place (PI. XI, ligs. 1 o, 1 p), and the calcareous lamina which fills it, the oral cryptocyst, joins a cry[)tocyst expansion developing on the inner side of the slernal area and taking its origin from the outer part of the single feneslrte. In contrast to the several times mentioned, rounded cryptocyst lamina, the sternal cryptocyst, we may call this the marginal cryptocyst. After having reached a certain size the cryptocyst lamina; of the single fenestrje unite together and with the oral crypto- cyst by means of a connective ridge formed across the inner surface of each sternal rib, and henceforth the marginal and the oral cryptocyst form a continu- ous ring-shaped expansion, gradually increasing in breadth. The oral cryptocyst i.ssuing from the junction of the horizontal and the obliquely ascending parts of the distal wall is directed proximally and frontally and increases in extent simul- taneously with a considerable increase in thickness on account of new calcareous layers being formed on its frontal surface. The sternal cry|)tocyst gradual!}' coa- lesces not only with the ribs but on both sides of these also with the outer (fenestral) jjarl of the marginal cryptocyst and this may lead to a complete oc- clusion of the fenestrse.
Setting aside the fact that from the daughter-zooecium of the bizocecial inter- node a number (up to 4) of successive, single zooecia may sometimes arise, the last of which completes the branch, the uni- and bizocecial segments otherwise alter- nate regularly in this species. With regard to the position of the separate zoa>cia we must notice, that the mother- and daughter-zoa^cium of the same segment have the acute-angled corners of their respective apertures directed towards each other, and the position of thg apertures of the succeeding single zocecia is the same. The above-mentioned, successive single zooL'cia all have the apertures situ- ated in the same way, whereas the aperture of the mother-zoa'cium in the bi- zoaH"ial segment has an inverted position in relation to the lower zoa'cium. The lateral branches, which always arise from the daughter-zoo'cia, spring alternately from the right and the left side.
For the sake of completeness I must further add that the colony is provided with radical fibres, which form close bundles along the basal side of the separate branches and spring from the basal side of the zorecium with which they communicate through a collection of numerous uniporous rosette-plates.
OcEcia are wanting in the colonies from the Bass' Strait, to which the above
15
226
description refers, hiil Ihcy are foiiiul in some eolonies of Ihe variety setigera originating from the same |)laee, wliieli among other things dillVr IVom Ihe main form in having the lateral chamhers extended over more than two-lhirds of the basal side of the zocecium and their membranous walls ending in a number of scattered chitinous denticles.
A gonozofficium with its covering kenozooecium bears a certain resemblance to a helmeted head and springs from a single zon-cium, which again springs from the mother-zooecium of a bizotecial segment. The gonozocecium and the covering kenozocecinm are of al)()ul the same size, and a transverse section through the centre of the entire complex has the form of a I'onndcd trapezium with a larger frontal and a smaller basal side and with two sides converging basally. The wide aperture, the operculum of which has a more strongly chitin- ized marginal portion, is shared in common by the gonozooecium and the keno- zooecium. It is bounded by a nujre strongly arched distal and a less strongly arched proximal margin, in the centre of which there is a short sulural line passing on to a small, transversely oval pore. The sternal area has 6 — 7 pear- shajjcd fenestra; disposed in an angle, of which the two distal are situated on a level with Ihe median pore. The lirsl j)air of ribs, which limit the aperture proximally, pass without any distinct boundary into the broadly rounded inner cryptocyst lamina, while Ihe second pair of libs, which are provided with an acutely projecting terminal part, meet in the above-mentioned suture on the proximal side of the aperture. Finally, the gonozooecium is on each .side provided with two large, flat, generally lra|)eziform lateral chambers (fig. 1 1), of which the dislal, which has 10 — I'l rosetle-|)lales, coiresponds to Ihe three distal lateral chambers and the proximal, with about 10 rosette-plales, to the pedal chamber. The real oo'cium is the helmet-shaped, arched distal wall of the gonozo(L'cium, the jjroximal, oblicpiely ascending part of which is provided wilh a very large number of uni|)orous rosette-plates. This oa'cium is again covered l)y a keno- zoo'cium, in which we may distinguish between a large, uncalcificd, saddle-shaped or liorse-shoe-shaped central i)ortion and two ])roximally continuous, but distally widely separated, calcified portions, a frontal and a basal one. The IVonlal sur- rounds the aperture dislally and is composed of two strongly arched lateral halves, which from their proximal part, situated dislally lo the Iwo lateral chambers, decrease in breadth towards the frontal end and are connected only by a very low portion on the distal side of the aperture. The basal part, which is bent towards the frontal side and which seen from the side is like the crest of a helmet, is rather narrow, frontally pointed and bounded by two curved, lateral margins (fig. 1 in). On either side between the two calcified jjortions the o(iH-iuni
227
itself is provided with two long but also broad and close bells of ])oies, while the calcified portions are connected willi tlie ocrciuni by a great many strong, cylindrical or conical spinous processes springing from the latter. A number of these [)rocesses outside tlie calcified portions serve to support the membranous part of the covering kenozooecium. In the approximate centre of the basal region we find the starting point of a small, meml)ranous, triangular chamber, which is ])rovided with a series of chitinous denticles along each lateral margin, and which communicates with the oa^cium through a triangular basal surface with two symmetrically arranged groups of o — 7 uniporous rosette-plates. A shoil, low, median, calcareous ridge springs from the |)roximal side of the basal surface and possibly originates from a median separating wall.
Scuticella ventricosa lUisk. Catenicella ventricosa Busk, Voyage of Rattlesnake, I, pag. 357, t. 1, fig. 1,
Catalogue of Marine Polyzoa, Cheilostomata, pag. 7, PI. II, figs. 1, 2. (PI. XX, figs. 5 a-.-) c (;i), PI. XI, tigs. 6a-61j).
The zocEcia hexagonally oval with an aperture bounded by a slighlly concave, proximal margin, which has an extremely short sutural line centrally. The slernal area is provided with 5—7 fenestra; converging at an acute angle, and the inner ciyplocyst lamina is of a triangularly pointed form and may allaiii about half the length of the sternal area.
The lateral chambers. Except on the adzoa-cial side of the daughter-zon'cium in a bizoo'cial segmeni, the scapular clunnbcr is everywhere developed as an avicularium with a small, oval mandible, and the supra-scapular chamber, the wall of which is only calcified in its outermost part distally to the avicularium, may end in a shorter or larger, ascending, pointed i)ortion. Proximally to the avicularium we find an oval infra-scapular and a very long, somewhat broader, pedally and more frontally directed cluunber, which occupies about fwo-lhirds of the whole lenglh of the zoa'cium. It is separated from the infra-scapular chamber by a horizontal or somewhat obli(|ue wall, and along its centre provided with a longitudinal row of 5 — 10 rosette-plates. Finally we find in the bizocrcial segment on the boundary between the mollu'r- and the daughter-zoa'ciuni n long, narrow, distally directed cavity (PI. XX, fig. 5 b, m. Ill), which almost reaches the i)edal chamber of the mother-zorecium proximally, and which communicates with the mother-zoo'cium through a row of 4 rosette-plates. It must be regarded as the adzoa'cial, inlVa-scapular chamber of the mother-zoa-cium.
The ooecium (PI. XI, figs. Ba — 6 b). The gonozooecium, which is about twice the length of the covering kenozoa-cium, is most often situated on the molher-
1.-.*
228
zotrciiiin of a hizoa'cial segment, hut is not iiifretjuently i'oiind on a single zore- cium. The aperture has a small iiidenlation in the middle ol' its proximal margin, while the structure of the sternal area and its cryptocyst lamina is similar to that of the zou'cia. Each of the lateral surfaces of the gonozod-cium communi- cates in the whole of its length with a large, long, lateral chamher provided with numerous rosette-plates, and this chamber, I believe, c()iresj)onds lo the long pedal chamber in the zoa-cium. The covering kenozoa'cium a little dislally lo the aper- ture has a transversely oval fenestra on each side through which the real on-cium can be seen, and above each fenestra a small avicularium, which on the inner side is in communication with a supra-scapular and on the outer and basal side with an infra-scapular chamber.
Form of colony. The regular alternation of the uni- and bi-zoo'cial inter- nodes is often interruj)led so that we may (ind several bizocrcial internodes suc- ceeding each other.
Of this species I have examined colonies from the Bass' Strait.
Scuticella maculata Busk. Catenicella ventricosa (var. maculata) Busk, Catalogue of Marine Polyzoa,
Cheilostomata, PI. Ill, fig. 4. (PI. XX, figs. 4a-Jl), I>1. XI, ligs. 7a-7c).
The zooecia large, broad, angularly o\al with a triangularly rounded aper- ture, which has an almost straight margin. The sternal area is of a structure similar to that in C. ucnlricosa, but it is provided with a broailer and more rounded cryptocyst lamina, and immediately on the |)roximal side of the aper- ture we find a transversely j)laced, inner cavity opening out into the aperture on either side of the short sutural line.
The lateral chambers. The scapular chamber is generally developed as an avicularium only on the outer side of the single zoa'cia, and the snjjra-scapular chamber has a steeply ascending, pointed, calcified outer wall. The form and the ])osition of the infra-scapular and the pedal chambers are similar lo those in (J. I'ciitricosd, but the two chambers are sci)araled by an obli([ue or nearly verti- cal wall. Here loo we find a long, narrow boundary chamber between the mother- and the daughler-zocrcium.
The ooecium (PI. XI, figs. 7 a — 7 c). The gonozoo'cium, the length of which may be contained about 2^/^ limes in the entire length of Ihe covering kenozooe- cium, is generally situated at the end of a branch formed by 1—4 zooecia spring- ing from a mother-zou-cium, and more seldom takes its origin directly from a molher-zoacium. The aperture has a small sinus in Ihe middle of its proximal
229
margin and on either side of this a robust, conical, obliquely ascending spine. The sternal area is i)rovided with a small fenestrse, and each of the lateral sur- faces of the gonozoa^cium with a pear-shaped oval, most probably pedal, lateral chamber. The frontal surface of the covering kenozowcium has 4 — 10 larger or smaller fenestrse of very variable form. When occurring in small numbers several of these fenestras are very large and show by their lobate form, that they have arisen by coalescence of several smaller ones. We may distinguish between an outer, arch-shaped group and a group on the distal side of the ajjerture. All four lateral chambers are developed, and the scapular one ai)j)ears as a small avicularium, while the two su])ra-scapular chand)ers have coalesced into one, which lakes up the entire breadth of the kenozott'cium (lig. 7 a), and which has on either side a vertical, pointed, calcified outer wall. This chamiier has besides a group of rosette-plates in the roof of each avicularium, a greal many scattered plates in the median part, which is separated by a low ridge from the frontal as well as from the dorsal surface of the kenozonecivim. On the outer and the basal side of the avicularium there is a small, oval, infra-scapular chandjer and separated from it a large, trapeziform pedal chamber.
Form of colony. Apart from the fact that rows of 1 — 5 single zooecia, (which may arise from both a mother- and a daughter-zocecium), may appear as ter- minal branches, the allernalion of uni- and bi-zocecial internodes is otherwise regular, and two bizooecial internodes nowhere succeed each other.
Of this species I have been able to examine some fragments from Port Wes- tern, Victoria (Miss Jellj).
Scuticella margaritacea Busk. Catenicella margaritacea Busk, Voyage of Rattlesnake, I, pag. 356, Catalogue of Marine Polyzoa, Cheiloslomata, pag. 9, PI. VI, tigs. 1, 2, 3. (PI. XX, fig. 3 a, 1^1. XI, figs. 5a-5 c). The zooecia rhombic-oval \Vith an aperture, the pi-oximal, more or less con- cave margin of which is provided centrally with a small, well defined, sometimes however quite rudimentary sinus, the entrance of which is bounded by two ex- tremely short spines directed somewhat distally and pointed at the end. These spines are sometimes widely separated, and the sinus then reaches its maximum (colonies from the Bass' Strait), sometimes almost concurrent at the ends and the sinus is then rudimentary or reduced to a pore (Port Phillip Heads). The operculum, which does not entirely till the aperture, has a proximal, concave margin, and the sternal area is provided with five fenestra; disposed in an arch or angularly. The cryptocyst lamina is of a broad, rounded triangular form, and
230
the strongly arched basal surface is divided into dendritically hianchcd longi- tudinal bells.
The lateral chambers. The scapular as well as the inlVa-scaiJular cluunber is Uirned sliglilly frontally. It is in most cases develojjed as an aviculariuni of very variable size, wliicli may allain a considerable, sometimes enormous size especially in the branches consisting of single zooecia only. The infra-scapular chamber, which has generally a long oval opening, terminates in a ])rojecling, conical, membranous portion, which forms an angle with llie aviculariuni. Tlie pedal clKunbei-, wliicli in tbe zoo'cia with a large avicularium almost reaches righl up to Hie infra-scapular chamber, is usually separated from Ihe laller by a rather short intermediate space. It is provided with a wholly frontal and at least in the single zoa>cia longitudinally oval or pear-shaped opening. The infra- scapular, adzocccial chamber of the mother-zocecium is wanting in Ihe bizoa-cial segment.
The ooecium. The gonozoa^cium, which is of about the same length as the covering kenozoci'cium, takes its origin either directly from a molber-zocrcium or from an inserted single zoa-cinni. The aperture is provided willi a broad, more or less regular, sometimes extremely indistinct sinus, in which the narrow distal ends of the two outermost of the ;5- o fenestra- of the sternal area often termin- ate. No sjjines. On either side 1 — 2 small, oval chandlers, Ihe distal of which is often very small or absent, sometimes on one sometimes on both sides.
The covering kenozoa'cium has on either side a large, long, frontally poiiiUil, basally broadl}' rounded, uncalcified portion, through which the oo'cium can be seen. The latter is here jjrovided with a longiludiually clid)-shaped, very dense collection of pores, the intermediate spaces of which partly project as tubercles. In the frontal portion between the tw'o areas as well as along the distal and proximal margins of the latter the oo'ciuui and the covering kenozooecium are connected with each other by a great many robust spinous processes, and the kenozon-ciuni has in the centre of its frontal surface a chamber develo])ed lo a varying extent, which is sometimes mostly mend)ranous and somelinies devel()|)ed as a rather high aviculariuni. In the latter case it is connected on eilhei' side wilh a [)artially mendiranous chamber, of which Ibe one si(k' joining the oj)er- cular end of the avicularium is somewhat higher than the otlu r. In sjiilc of the median position of these chandjers they may be regarded as corresponding lo the three lateral chambers on one side in an ordinary zon-cium.
Form of colony. In Ihe ])rincipal axis and Ihe iirincipal branches springing from it two bizoa-cial segments succeed each other with a single zou'cium be- tween {'2, 2, 1, 2, 2, 1 ).
231
Scuticella margaritacea, var. fissurata ii.
(I'l. XX, ligs. 3 b, 3 e).
This form, which may for the present be regarded as a variety, differs from the main form in the following characters. The relatively large sinus is bounded by two short, broad, hollow spines, which are open at the end and which form the greater part of the proximal margin of the aperture. The mother-zo(i>cium of the bizoo^cial segment has a slit-like, adzod'cial, infra-scapular chamber. The frontal surface of the gonozocrcium is on either side provided with two rounded lateral chambers, and its aperture has a well develoi)ed, rather deep sinus, which like the zou'cial a|)erture is bounded by two short, broad, hollow spines open at the end. The oa-cium lacks the two groups of closely situated pores, and the kenozod-cium has at its top a high aviculariuni, which communicates with two une(iually large, partially mem!)ranous lateral chambers.
Of this form I have examined colonies from Port Phillip, Australia.
Scuticella urnula Mac Gilliv. Catenicella urnula Mac Gillivray, Transactions and Proceedings of the Royal
Soc. of Victoria for l.S.SIJ, Vol. XXIII, pag. 34, PI. I, figs. 2, 2 a, 1887. (PL XX, figs. 1 a— 1 e, PI. XI, ligs. 4 a, 4 b).
The zocecia large, rhombic-oval with a longitudinally rounded aperture, bounded by a concave proximal margin. The long, oval sternal area is provided with .1 — 7 pear-shaped fenestrse and with a long, tongue-shaped cryptocyst lamina, which often reaches the starting point of the proximal fenestra. The compara- tively large, deep, sternal sinus is occupied by 2 — 5 ribs or spines, of which the two distal are very high and the proximal, when occurring, are very small and tubercle-shaped.
The lateral chambers. The scapular chamber is in most zooecia developed as a good-sized, more or les§ complete avicularium with the aperture frontally directed and in the complete state with a short and broadly triangular mandible. It is, chiefly on account of its arched outer wall, well separated from the zocr- cium, and the pointed lamina springing from its top, which forms the outer wall of the supra-scapular, for the rest membranous chamber, gives it a certain likeness to the lobe of an ear in a mammal. On the adzorecial surface of the daughter- zoo^cium it is a low mend^ranous cavity, which, apart from a separating line but partly developed, has fused with the corresponding chamber of the mother- zocccium. The scapular chamber is often more or less incompletely developed on one or on both sides of a greater or smaller number of the zoo'cia succeeding
232
the daughter-zocecium. This inconiplcleness mosi often means the ahsence of the mandible and transverse bar in the apertnre, and as a rule also a more or less incomplete calcifieation of the wall sejiaraling the scapular from the infra-scapular chamber. The infra-scapular and the jiedal chambers, whose boundary ridges towards the frontal surface of the zooccium give the latter a rhombic form, are separated by a ridge running obliquely basally and ])roximally. These chanibcrs take up not only the lateral surfaces but also the greater pail of llic basal sur- face, along the midiile of which they are separated by a rathei' narrow longi- tudinal bell (IM. XI, ligs. 4 a, 4 ])). The infra-scapular chandler communicates with the zoo'cium by uj) to l(t rosette-plates and with the avicularium by only 1 — 2. The molher-zoa'cium is provided with a long, narrow, adzotrcial, infra- scapular chamber.
The ooecium. The gonozoa'cium, which is considerably smaller than the covering kenozoax'ium, is situated sometimes on a molher-zo(rcium, sometimes on an inserted single zoo'cium. The aperture has a very broad and deep sinus, consisting of a wider outer part, which is bounded bj' two arch-shaped, in- wardly converging margins, and of a narrower inner part, which has a small, rounded process on either side. The sternal area is provided with 7 — 9 very narrow fenestra; and with a broad cryptocyst lamina, while each lateral surface is occupied bj' two large lateral chambers separated by an angulated ridge. The covering kenozooecium distally to the aperture on either side has a very irregular, transversely oval or bean-shaped, often more or less sharply sinuated or lobed uncalcified portion with a cryptocyst dei)ression in its marginal portion. On its surface we find (j — 10 chambers of most variable form, which are covered by a membranous roof and bounded only by low ridges. Distally to and outside the two uncalcified areas there is on both sides either one very long and rounded or two adjacent chambers, a larger and a smaller one. On the basal side of the o(i!cium we find three, a smaller unpaired one proximally and two adjacent ones distally, the proximal half of which may somelinies l)e provided with a sepaialiug ridge. On the frontal side of this group we find again a sejiarale one ending in a very thin point (figs. 1 b, 1 e), while its basal part lias two bulgings which may be separated as indejicndent chambers.
Form of colony. We may find rows of up to f) single zotrcia s|)ringing from a daughter-zoo'cium, but otherwise the alternation of uni- and bi-zocecial inter- nodes is regular.
Of this species I have examined a colony from Port Philli]) Heads (Miss Jelly).
2:?3
Scuticella sacculata l^usk. Catenicella sacculata Busk, Challenger, Zoology, Vol. X, Part I, pag. 12, PI. 1, (ig. 7.
(PI. XII, ng. 2 a).
The zooecia, the surface ol' which is provided with a number of very small, widely scattered pores, are long, slender and constantly increasing in breadth Irom the very narrow proximal end towards the aperture, from which the lateral margins again converge distally. The aperture has a slightly concave proximal margin, and Ihe extremely small sternal area has ])ut a single, small, round fenestra proximally. The sternal sinus is occuj)ied by three spines, of which the proximal, rudimentary one is solid, while the two others, which meet in a sutural line, have an inner cavity opening outwards through a small pore near the di.s- lal margin. The sternal cryptocysl lamina has an arch-shaped proximal margin, which is clearly visible on Ihe frontal surface through Ihe only opening of the htller.
The lateral chambers. The scapular chamber is everywhere except on the adzoa^cial side of the daughter-zocrcium developed as a medium-sized, rather strongly projecting and somewhat ascending avicularium, which is direcled out- wards and slightly basally. The other chambers are wholly membranous and bounded only by low calcareous ridges. The supra-scapular one, of which but an extremely small part is seen on the basal surface, on the frontal surface almost reaches the distal margin of the ajjcrture and Ihe outer end of Ihe roof of the avicularium. The infra-scapular one, which is direcled laterally, is ralher large and of an oblong, (juadrangular or pentagonal form. It is separated by a small intermediate space from the very long and rather broad pedal chamber, which is situated a little more frontally and occupies about two-thirds of the whole length of the zoa-cium. Along its middle we lind a row of 6 — 7 rosette- plates. The mother-zoa'cium is provided with a long, narrow, infra-scapular ad- zon'cial chamber.
Ooecia have hitherto not been found.
This species may l)e regarded as a transitional lorui between Scuticelld and Cdleiutriii. I have been able to examine a small fragment of il, for which I owe IhanUs to the direction of the British Museum.
Costiceila n. g.
The sternal area, which is provided with 4 — 14 fenesfrse, disposed in a curved line, and with a cryptocysl lamina of a similar outline, is to a greater or smaller extent formed by a number of generally hollow spines, springing from the sternal
234
sinus and separaled l)y fissures. Hinge-teelh riidinienlary or indislinci, ni'vcr pro- jecting I'leely in the aperture. The supra-scapular chanil)er with a calcilied roof. The occlusion takes place in a similar way to that in Sciiticella.
Besides in the ahove nienlioned characters the four species heie described correspond in the folioNving. The scapular chamber is generally developed as a small avicuhniuni also on the adzod'cial side of Ihe daughter-zon'ciiiiu, and Ihe first three lateral chambers form a more or less compressed, piolruding and somewhat frontally directed, wholly or mostly calcified portion, which is separated from the frontally directed pedal chamber by a rather large intermediate space. There is a very small supra-scapular clKunber on the adzod'cial side of Ihe mother-zott'cium and a [)edal chamber on Ihe adzooecial side ol" the daughler- zoo'cium. The l)asal wall of the zoircia has a more or less distinct, longitudinal strialion. The gonozo(ecia, situated either on a mother-zocx'cium or on an inserted zooeciuni, are always provided with at least two frontally directed lateral cham- bers, which must be regarded as the scapular and the pedal. The frontal surface of the covering kenozott-cium has two large, transversely oval fenestras, and within each of these we find on the ooeciuni a long, dense collection of spinous pro- cesses and tubercles, among which numerous pores are generally discovered. Further a larger or smaller part of the frontal surface of the true oa'cium is provided with robust spinous processes, which have coalesced with the inner surface of the kenozoa^cium. On the top of the latter we sometimes find a small kenozoa'cium, sometimes a small avicularium communicating on either side with a small calcified lateral chamber.
Costicella solida n. sp.
(1^1. XX, fi«. 7 a, l>\. XII, tigs. 1 k, 1 li).
The sternal area, which is not much longer than the aperture, has 5 — 6 fenestrse situated in a broad curve, within which a ([uadrangularly rounded cryp- tocyst lamina is seen. In the inner part of the area there are 5 — 7 very short spines separated by distinct fissures, which show great variation in respect to their mutual connection. The two distal ones are generally very high and plate- shaped, and each of them has most fie(juently a larger or smaller, often bifur- cate, inner cavity, which is connected with a pore in the middle of the oral margin. In Ihe others Ihe inner cavity is usually wanting or if i)resent extremely narrow.
The lateral chambers. The supia-scapular chamber has a triangular excision on its frontal surface near the ajierture and a smaller one in the outernu)st, proximal part of Ihe basal surface, .while the infra-scapular and Ihe [)edal cliam-
235
hers liave a rather large, oblong, frontal opening. On the adzooecial side of the daughter-zoa-ciiim the three distal chanihers have coalesced into a single cavity, and an aviculariuni is accordingly wanting. The niolher-zoa'ciuni has a very small, slit-like, infra-scapular adzorecial chamber.
The ooecium (PI. XII, (ig. 1 k). The gonozooecium, which sometimes springs from a mother-zo<L'cium, sometimes from an inserted single zoa-cium, is approxi- mately of the same size as the covering kenozooecium, and together they are of a broad, hexagonal ly rounded form with two parallel lateral margins curving in- wards a little. The sternal area has .'5 small fenestra- and 3 — 5 spines separated by short fissures. The two distal spines, which meet in the oral suture, have a large inner cavity connected with a large oval pore in the oral margin. The others are very short and generally have no inner cavity. Within the very broad fenestra; of the kenozocecium pores as well as numerous spinous processes are seen, while the supporting |)rocesses, which reach the calcareous roof of the keno- zoa^cium, are most numerous in the portion between the two fenestra.*. On the side of these fenestras we find a continuation of this median portion, which goes as far as the aperture and is bounded by two lateral margins converging towards the latter. A small median chamber may appear on the top of the kenozooecium. It is always found in specimens from the Bass' Strait, in which it is very oblong and provided with one or several slit-like openings in the roof. On the other hand its appearance is very inconstant in colonies from Port Phillip, in which il is very small, oval and only calcified at its base.
Form of colony. In all the principal branches and sometimes also in some of the secondary branches two bizoa'cial internodes succeed each other (2, 2, 1, 2 2 1 )
Of this species I have examined colonies from Port Phillip and the Bass' Strait.
Costicella cuspidata n. sp.
! 1>1. XX, ligs. f) a-(i c). The sternal area, which may be longer Iban the aperture by a half, is j)rovided with 7 — 10 small feneslraj disposed in a broad curve, and within these there are. 6 — 8 smaller ones, of which one is generally situated in the central line far back. In the central portion of the area we see three, more seldom four s]iines, of which the Iwo large, plate-shaped distal ones have an inner, most IVeipieiiliy three- or four-branched cavity connected with as many pores, of which we usu- ally find one on each side of the proximal margin of the aperture. Very often, perhaps in most cases, the cavities of the two large spines communicate through
2:56
a broader or narrower Iransverse l)rancli. In a small, niosl ol'k'n Irianf^nlar open- ing, situated proxinially to llie Iwo large spines, we lind generally hnl a single, very sliorl, rndinienlary, solid spine, more rarely two.
The lateral chambers. The sii])ra-seapular chamber has a number of scat- tered pores, and in the proximal pari of the basal surface a rounded excision, which is somewhat larger liiaii these. The infra-scapular chamber has a small, round or oval opening proximally, and the small ])edal chamber an oval or long frontal opening, which is niiicii larger. The mother-zoa'cium has no adzoo'cial, infra-scaindar chandjcr. It is characteristic of this species Ihal the last of (he zoa^cia completing a row sj)ringing from a daughlcr-zoo-cium has a lerminal, coini)resse(l, narrow, rhond)ically rounded chaini)tT (I'l. XX, lig. (> !)).
The ooecium. 'I'he gonozocrcium, which is but half as high as the covering kenozoa'cinm, is sometimes Ijorne by a mother-zoa'cium, sometimes by an in- serted single zoo;ciuni. It is provided with a rather broad but low frontal sinus, which is bounded on either side by a very short somewhat bent spine, and lliiis the single pair of spines do nol meet as in the other sj)ecies. The sternal area is much reduced and has 5 very small fenestras situated immedialely on the proximal side of the aperture. Along its frontal, central line the covering keno- zooecium is provided with two rather large ])ores, which may be somelimes single, sometimes more or less deeply divided by a tongue springing from I heir dislal margin. The two groujis of jiores and spinous processes within the long, hderal fenestra^ meet in a median, generally angularly bent j)ortion, which reaches the proximal of the two median pores. The small, terminal kenozocccium is s(jme- times developed as an aviculaiium and then communicates wilh two small cavities.
Form of colony. In the principal branches two l)izo(ecial inlernodi's succeed each other (2, 2, 1, 2, 2, 1 ....).
Of this species I have examined colonies from I'orl Phillip.
Costicella hastata Jkisk.
Calenicella liaslala Husk, Voyage of Rattlesnake, I, pag. .'{.');), Catalogue of Marine
Polyzoa, Pari I, p. 7, PI. 11, ligs. ;{, 4.
(I'l. XII, (l-s. I e, 1 (I, 1 f, I n, 1 J, 1']. X\, li.i^s. Sa, SI)).
The sternal area, which may be about twice the length of the ai)erture, lias
7 — 1) fenestra', disposed in a long curve, and as many hollow spines, of which
each is provided wilh a |)ore in or towards the end. I-^acb of the spines in the
lirsl pair has however olliii two, which llien corres])ond with a bifuri'ale cavity.
The lateral chambers. The supra-scapular clKuuber, which may somelimes
237
(e. g. in a form iVoin Twofold Bay) l)e very long and poinlcd, is, apart from a number of scattered pores, wholly calcified. The infra-scapular has a small, ob- long opening on the ])asal side and a smaller one on the fronlal side, and the pedal chamber has most often a long, narrow frontal opening. The mother- zott'cium has an extremely small, slit-like, adzou?cial, infra-scapular chamber (ni. III).
The ooecium. The gonozooeciuni, which is but half as long as the covering kenozooecium, is situated on a mother-zooecium. Its sternal area is as long as the aperture and provided with 4 — 5 small fenestrse and as many spines, of which the two distal are much higher than the others. Each of these has a large, inner cavity with generally three pores, of which two are seen just inside the oral margin. The other spines are short and narrow, and the inner cavity may often be wanting. The high kenozoa>cium has dislally to the aperture a longitudinal belt bounded by two parallel lateral margins. This bell reaches the two lateral fenestra; and has a small, oval pore proximally. Within each of (he two long lateral fenestrse we see an oblong group of pores, the projecting reticulation of which does not, or but to a small extent, end in spinous processes. The support- ing processes springing from the owcium apjiear in great numbers over the larger part of the frontal surface. On the top of the kenozoa>cium there is sometimes a small, rounded, compressed, wholly calcified cavity, sometimes an avicularium, which again communicates with two lateral cavities.
Form of colony. In the principal branches the uni- and bi-zocrcial inter- nodes alternate according to the formula 2, 2, 1, 2, 2, 1 ... .
Of this species I have examined colonies from Port Phillip and from Two- fold Bay.
Costicella benecostata n. sp.
(I'l. XII, ligs. 1 ;i, 1 I), IM. \X, lit^s. 9 a).
The sternal area, which is about twice the length of the aperture, is [)ro\ ided with 8 — 14 small, round fenestrse, and with as many hollow spines separated by distinct fissures. Most of these s[)ines are rather high, (piadrangular and only the two or three proximal ones are conical. The first two spines are much higher than the others, but the inner cavity is often comparatively small. Further, the relative position of the two rows of spines may vary considerably, as they may sometimes be wholly or partly opposite, sometimes wholl)' or ])arlly alternate.
The lateral chambers are much more calcified than in tlie other species, and with exception of the supra-scapular one, which has on its basal surface I wo small excisions, they have but a few pores. The scapular clKunber, which
238
is also developed as an aviciilariiiiii on llie adzorrcial side of the daugliter-zooe- c'iuni, is very small, arched and ralher slronglj' |)rojecting. The adzo(t'rial, inlVa- scapular chamber of the molher-zoa'cium is not developed.
The ooecium. The gonozocrcium springs from a molhcr-zotrciiini and is of about the length of an ordinary zoo'cium, but much broader and 3 — 4 times as long as the small, cap-shaj)cd, covering kenozooecium. The slruclure of the sternal area is similar to Ihat of the ordinary zoa'cia, and Ibis may also be said of the lateral chambers on the adzorrcial side with exception of the first one, which is smaller and more steeply ascending. On the adzooecial side of Ihe gonozoo'cium the lateral chambers are much more faintly developed, silualcd almost vertically on the frontal wall, and the scapular chand)er is not developed as an avicu- larium. No unpaired, median pores are found, and within the two Iransver.sely oval fenestra", which are heie <piilc frontal, we find but one group of spinous processes and no pores. On the lo|) of liie kenozoojciiim Ihere is a rather large, quadrangular or triangular chamber, compressed from front to base, which is sometimes undivided, sometimes disided bj' two septa into three cavities, of which the central one was not developed as an avicularium on anj' specimen I have examined.
Form of colony. The regular alternation of uni- and bi-zou'cial inleinodes is broken in the terminal part of the princi[)al branches by two or three bizoo'cial inlernodes succeeding each other (2, 2, 1, 2, 2, 1 ... . or 2, 2, 2, 1 ... .).
Of tills species I have examined some fragments from Port Western.
Besides the four, above-descril)('d species whicli show a uundier of agreeuienls with Scnlicella manjarilacea, it seems, that the following tertiary species described by Mac Gillivray' must be referred to this genus, viz. Cdlenicelln lincata. (jtl. latijioiis and Ckiinporella lomjicollis.
Cribricella n. g.
The slenial area has numerous, scattered ])ores, of which the outermost are disposed in a distinct curved line, and a small, transversely oval cryptocysl lamina on its inner surface. The hinge-teeth are rudimentary or indistinct and never jirojecting freely in Ihe a])erlnre. The occlusion lakes ])lace in a way similar to that in Scnlicella.
' 76, p. 14, 1,'), 2\.
239
Cribricella rufa Mac Gillivray. Catenicella rufa M. Gillivr., Transact. Royal Soc. of Victoria 1868,
Vol. IX, pag. 126. (PI. XII, figs. 7 a-7 f).
The zooecia are elongated, ciuadrangularly oval, and the sternal area is pro- vided with numerous scattered pores, of which the outermost are not much larger than those situated further in. The aperture has a proximal concave margin with a small, rounded sinus centrally.
The lateral chambers. The scapular chamber is in most zorrcia developed as a generally rather small, frontally directed avicularium, which never appears on the adzocecial side of the daughter-zooecium. It is usually wanting on the inner side of the single zoa-cia, which occur in rows and may spring both from a mother- and from a daughler-zofrcium, but in the latter case the opposite avi- cularium is often large. Of the other lateral chambers we see from the frontal surface only a part of the supra-sca[)ular one, which has a membranous roof but a jjrojecting calcified outer wall. The long, narrow infra-scapular chamber passing from the outer side of the avicularium obliquely towards the basal surface bends again more or less far down the latter surface and is at its terminal part almost i)arallcl with the likewise long, narrow pedal chamber, which runs along the lateral margin of the zoa'cium. The mother-zooecium has a long, infra-scapular, adzocecial chamber.
The ooecium. The gonozocrcium, which is somewhat shorter than the cover- ing kenozoa'cium and situated on a mother-zoa'cium, is of the same length but twice the breadth of the zoa^cia, and the structure of the sternal area is similar to that of the latter. Its wide aperture has a broad, but indistinctly marked sinus, on the proximal side of which a short, broadly rounded, inner cryi)tocyst plate is seen. Along each lateral margin we find a long, narrow, pedal chamber, bas- ally to which there is a shorter, somewhat curved one, and the chanil)ers corre- spond to those of the distal group. The large covering kenozooecium is on its frontal surface provided with numerous, scattered, rather large jiores, and the distal group of lateral chambers is generally represented on either side by an oblong, mostly membranous cavity, in which we maj' distinguish between a shorter and wider distal part, which can be seen from the frontal surface, and a longer, more narrow, somewhat curved part, which reaches halfway down llie basal surface. The projecting wider part, which is often conical, may have more or less strongly calcified walls and often be provided with but a narrow, slit-like opening. In a single case it was only present on one side and then communi-
240
cated willi :i \eiv smnll ;i\ iciilnriiiin. The [icdnl Inlciiil cliamlxT is icpii^scnUHl by Iwo (nicnc seldom by tliici') mcinhriinous cavilics of soiiu'wlial vaiiahlc Ibriii and size.
Form of colony, ^\'llile uni- and i)i-zooecial inlciiiodes seem to alternate regularly everywiuTi' in the ])rincipal branches, we may lind two hizod'cial inler- nodes succeeding each other immediately on the proximal side of the ooicium.
Of this species I have examined colonies from Port Phillip and from Port Phillip Heads, Victoria (iMiss .lelly).
Cribricella cribraria Busk.
Catenicella cribraria Husk, ^'()yage of Rattlesnake, I, i)ag. ^51), (catalogue of Marine
Polyzoa, Cheilostomata, i)ag. 9, PI. V, fig. 3 — 4, Challenger, Zoology,
Vol. X, Part 1, pag. 11, lig. (5.
(I'l. Xll, lif>s. 8 a— Sc).
The zooecia broadly oval. The sternal area with numerous pores, of which those situated in the margin are much larger than those scattered inside. The aperture with a proximal concave margin, from the centre of which issues a sutural line. This line separates two short, plale-shaj)e(l, hollow spines, which are provided with snmll pores and may be strongly arched. There is a narrow, curved transverse slit on the proximal side of the aperture.
The lateral chambers. The scapular chamber is everywhere, also on the ad- zoa'cial side of the daughter-zocecium, developed as a large, compressed avicu- larium, the strongly concave frontal surface of which is bounded at both ends by a process. The supra-scapular chamber, which is almost wholly calcified, is long, narrow and provided with a curved terminal part. A very short lateral branch ending in a pore starts from the proximal half of its frontal side and its bent i)roximal end, which can be seen from the basal surface, likewise termin- ates in an uncalcified portion. The infra-scaj)ular and the |)edal chambers are well separated, long, narrow and provided with a longitudinal slit. An infra- scapular, adzod'cial chamber is wanting in the mother-zoo'cium.
The ocEcium. The gonozou>cium, which is twice as high as the covering kenozoceciuni, is situated sometimes on a motber-zou'cium, sometimes on an in- serted zod'cium. The sternal area is somewhat depressed and provided with numerous scattered pores, of which the inner ones are in part larger than on the zotrcium. The aperture has an almost straight jjroximal margin, and there are no hollow spines. Two very narrow lateral chambers with a slil-likt' opening are found along each lateral margin. The covering kenozod-cium has a distal, more strongly arched, indistinctly marked portion and on each side a large, pear-shaped
241
or triangular fenestra. Within tlie latter the on'cinm shows an irregular collect- ion of very small pores. Numerous spinous jjiocesses are found outside the two feneslrse and in the region hetween them.
Form of colony, hi the principal hranches we find everywhere a regular alternation of uni- and hi-zoa'cial internodes, and hranches of u|) to <S single zod'cia may spring from Ihc daughler-zoa^cium.
Of this s[)ecies I have examinetl colonies from l\n[ Weslern, liass' Strait and from New Zealand (Akaroa). I only found a few ocrcia on the latter.
Hincksiella n. g.
The stenuil aica has a nund^er of feneslraj disposed in a curve, but no cryp- tocyst lamina. Hinge-teeth rudimentary or indistinct not projecting in the aper- ture. Of lateral chambers only the supra-scapular and the scaj)ular occur, and the.se form together a wing-like llange on either side of the /od'cium. The occlu- sion takes place in a way similar to that in Scuticella.
Hincksiella pulchella Maplcslone. Catenicella i)ulchella Mai)leslone, Journal Micr. Soc. Vicloria, Vol. 1, 1880,
pag. 64, PI. V, fig. 4. — — Busk, (Challenger, Zoology, Vol. X, Part I, pag. 13,
I'l. I, (ig. 4. (PI. XII, figs. 9n-0c). The zooecia oval, with a longitudinally striated basal surface and with a slightly arched sternal area, which has 6—^7 oval fenestrae on either side. The aperture has a proximal concave margin with a small sinus centrally, the entrance of which is narrowed by two short, somewhat bent, dentiform pro- cesses. The zoa'cium is separated from the lateral chambers by very tliick walls (fig. 9 c) and the zoa^cial margins between the fenestrae and the lateral chambers are therefore very dark.
The lateral chambers form a wing-like flange in (he entire length of the zooecium. They are wholly calcified and apart from a pore at the end of the triangular, steeply ascending, supra-scapular chamber, they are other- wise without pores. The scapular chamber, which communicates distally with the zooecium through 1 — 2 uniporous rosette-plales, is everywhere, also on the adzocecial side of the daughter-zocecium, developed as an avicularium and provided with a very small, proximally directed mandible. A pedal chamber is not developed and the adzoa'cial, infra-scapular chamber of the mother-zoa-cium
IS wanting.
16
242
The ooecium. In the two cases hitherto round the gonozooecium is a inother- zott'ciuin situated on a single zooeciiini. It is covered l)y a zoa?cium of ordinary structure, which only shows any difference in having a nund)er of scalteretl pores in its frontal wall which does not seem to he specially strongly arched. Nor does this covering-zoa'ciuni coniplele the branch, hut may he succeeded hy at least one single zoojciuin. Tlie aperture of the gonozoa'ciuni has a ])r()xiniai concave margin with acute corners.
Form of colony. The alternation of uni- and hi-zod'cial internodes is regular.
Ol this species I have examined some small colonies from Port Phillip Heads.
Claviporella M. Gillivray, char, emend.
The aperture is provided with a more or less deep sinus and with two robust, strongly projecting hinge-teeth. Behind the aperture there is an inner cryptocyst lamina and most often an oval, median pore, a remnant from the primary frontal sinus. On either side of the aperture is a cylindrical acropetal spine, and the pedal chamber, situated far ])roximalIy, is rudimentary and only commimicales with Ibe zoa'ciuni through a single rosette-plate. The occlusion takes place in a way similar to that in Scuticella.
Claviporella geminata W. Thomps. Catenicella geminata ^^^ Thompson, Nat. Hist. Review, V, 18r)8.
Proceed. Dublin Univ. Zool. and Botan. Associat. I, i)ag. S J, PI. VII, figs. 3, 4.
(I'l. XII. li^s. 3a, .■?])).
The zooecia, which excluding the lateral chambers are rounded trapezi- form, have a number of very small scattered pores, and the sternal area gener- ally shows 2- '), most often very small fenestra\ The aperture, the sinus of which is twice as long as broad, is surrounded by '2 — 4 acropetalous spines of very varying size, 2 distal, frontally directed ones and two lateral, the two former of which diverge very little and may attain the length of the aperture on the single zofpcia. On the mother-zoctcium they are but small, and this is always true of the lateral ones, wliicii are most often rudimentary or absent on the single zod'cia. On the proximal side of the sinus a moic or less distinct sulural line leads down to a small, very narrow pore, the margins of which are gener- ally provided with small, dentiform |)rocesses. The two short, broad spines, which meet in the sutural line, do not show any vestige of an inner cavity.
The lateral chambers. The scapular chandler is everywhere, also on the ad- zoa-cia! side of the daughter-zo(rcium, developed as a somewhat compressed avi-
2415
cularium of very variable size, the distal wall of which terminates in a beaked hook. This aviculariuni may sometimes attain the size of the zod^ciuni. The supra-scapular chamber is separated frem the aviculariuni by a straight wall. It is a compressed, roundedly triangular cavity, increasing outwards in height, which is wholly calcified with exception of a narrow, oval fissure in the inner part of its roof. The infra-scapular chamber is furnished with a righl-angled or acute- angled corner, which forms almo.st a right angle with the frontal surface of the aviculariuni. It is compressed, trapeziform and calcified wilh exceplion of the surface forming an angle with the aviculariuni. On the adzoo'cial side of the mother-zoa^cium proxinially lo Hie aviculariuni of the daughlcr-zod'cium (here is a small supra-scapular chamber and on the proximal side of llu- lateral spine we find an extremely small, rounded chamber, which must be regarded as Hie adzooecial, infra-scapular chamber of the mother-zocecium. A pedal chamber is wanting on (he daughter-zocecium, but found on both sides of Hie mother- zott'cium.
The ooecium. The gonozooeciuni is a mother-zocecium and differs from the ordinary zoa-cia in wauling the two distal sjiincs and in liaving a broader sinus in the aperture. The ooecium is covered by the distal zooecium, which is accord- ingly provided on one side with a strongly arched expansion, the surface of which has a number of scattered, wart-like i)i-ojecling pores.
Form of colony, 'fhe principal branches are composed solely of bizooecial internodes, in which the mother-zod'ciuni bears a considerably larger aviculariuni than the daiigbter-zoa'cium and appears alternately to the right and to the left. A single zod'cium may spring only from the daugliter-zo(i>cium.
Of this .species I have seen a few fragments from Port Phillip.
Claviporella aurita Busk.
Catenicella aurita Busk, Catalogue of Marine Polyzoa, Cheilostomata,
pag. 8, PI. IV, figs. 1, 2, 3.
(PI. XX, fii^s. 10:1, 10 1)).
The zooecia oval or angularly oval with very few, scattered, fine i)ores, and wilh a sternal area provided with 3 — .') rather small fenestra'. The aperture, the sinus of which is not longer than broad, is surrounded by 4 acropctalous spines of very variable size, two distal and two lateral ones, of which the two former, which diverge at a right or obtuse angle, are of a robust cylindrical form and may become a little longer than the aperture. The two lateral ones are consider- ablj' smaller and never seem to be wanting. A sulural line leads from the sinus
Ui*
244
down lo an oval pore, and on L-itlier side of llie suliire we generally lind an inner cavity belonging lo the two short s])ines, which meet in the latter.
The lateral chambers. The scapular chaniher, which in contrast to that in the ])rcceding species, has no beaked hook, is not everywhere developed as an avicu- hirinni and is often absent on the one side of a single zoirciuni as well as of a bizofficial internode. While the three distal lateral chambers together form a body of a shape somewhat similar to that in the foregoing species, the extent of the three chambers separately is diilVrenl, the scapular cliainl)er being dilated both distally and jjroximally al the expense of the two other clianihers, and the sinus, which in CI. (jcinindta is formed between Die scapular and the infra-scapular chamber, is here formed by the former only, the septum between the two cliani- hers having retreated much farther pro\inially. The supra-scapular chamber is separated from the scapular by an angulated septum and has a lissure in its roof. II is an extremely small, triangular or (piadrangular cavity, which together with the distal part of the scapular chamber forms a rounded jirocess, the form and position of which reminds one of the distal sjiines. The infra-scajjular chamber is generally triangular and wholly calcified with exception of a small frontal pore. The pedal chamber appears in the same way as in the foregoing species. This may also be said of the above-mentioned chamber on the bizooecial internode.
The ooecium. The gonozoceciuni is a single zocrcium, and the covering keno- zoircium is of the length of the gonozocrcium and has a depression along the centre of the frontal surface, which is provided with a numlier of widely scat- tered pores. The aperture, which is provided with two distally converging, arch- shaped lateral margins, has a broad, Irapeziformly rounded sinus, the proximal part of which is covered by the spines which meet in the sutural line. On either side of the ai)erture we find a distally directed, strong, conical, lateral spine of the length of the aperture, and outside this on either side a single, rounded (piad- rangular, lateral chamber with a small rounded pore.
Form of colony. Uni- and bi-zocecial internodes alternate, i)iit in such a way that two bizod'cial internodes succeed each other rather frequently. The single zooecia may spring from the <laughler-zooccia in rows of up to 5. They are sometimes on the outer side provided with an avicularium, which may exceed the zoa'cium in size, and such an enormous avicularium is found especially in a form from Akaroa (New Zealand).
Of this species I have examined colonics from Port Phillii), Auckland, Cape Wilson and New Zealand.
245
Claviporella pusilla Wilson. Catenicellopsis pusilla Wilson, Quart. Journal Micr. Soc. Victoria, 1880, pag. 64. — — Mac. Gillivray, Mc. Coy, Prodromus ol' the Zoology of
Victoria, decade XI, pag. 29, PI. 107. figs. 1 — 1 c. (I'l. XII, lij^s. 4a-ll).
The zooecia are [)ear-shaped, very strongly arched and piovided with small, scattered pores. The small sternal area has hut a single, very small fenestra he- sides the larger median one, situated j)roximally to the sutural line, and the two spines, meeting in the latter, have often an inner cavity. The a|)erture has a rather hroad, rounded sinus, on the distal side of which we find two widely separated, slightly diverging, generally slender, cylindrical spines. Special lateral spines are wanting, the rohust, spine-like process on either side of the aperture heing the scajjular chandler.
The lateral chambers. As far as 1 can see on the examined I'ragments the scapular chand)er is everywhere developed into an avicularium with a small, triangular mandihle (fig. 4 g). The chamher itself is of a shorl, thick, robust, cylindrical or conical form and is wholly calcified. A supra-scapular chamber seems to he wanting, and in the proximal part of the avicularian chamber is found a small, rudimentary, infra-scapular chamher. As in the other two species a rudimentary, pedal chamber is present, whereas there is no small chamber on the boundary between the mother- and the daughter-zooecium.
The ooecium. The gonozocvcium is a mother-zoa'cium. The form of its aj)er- lure is similar to that of the gonozorecium in CI. aiirihi, and here too a smaller or larger part of the sinus may be covered by the two spines. The scapular chamber on the adzoa-cial side is not developed as an avicularium and is shaped like a strong, somewhat bent spine of the length of Ihe aperture. At its proximal part there is a rudimentary, infra-scapular chamber. The covering zoa?cium, the arched, covering part of whiclr is provided with a number of scattered pores, lacks the small i)ore of the sternal area as well as the rudimentary i)edal cham- her. The internode is not completed by Ihe covering zoa'cium any more than in (II. <n'min<tUi.
Form of colony. In the principal branches uni- and i)i-zo(rcial internodes alternate regularly and rows of single zoo'cia ap|)(ar.
Of this species I have examined some dead colonies from Victoiia, most zooe- cia of which had been attacked by alga- and Foraminifera.
24(5
Pterocella n. g.
The steriKil area has ;{ — 7 fenestra! disposeti in a curve and a rouiuled ervplo- cysl lamina on its inner surface. The ajierture, tlie |)()sterior part of which is Irapeziforni or arch-shajied, is provided willi Iwo slroni;ly developed, IVeely jiro- jecting hinge-teeth. The lateral chainhers form a wing-like marginal portion on either side in the whole length of the zo(L'cium. The molher-zoo'cium has a small (ii)icnl(triniii on its adzod'cial side. The occlusion lakes place in a way similar to that in Sciilicclld.
Pterocella alata Wyv. Thompson. Catenicella alata \\'yv. Thompson, Nat. Hist. He\ie\v, ISfjiS.
Proceed. Dublin Univ. Zool. and IJolan. Associat. I, pag. 80, PI. VI. fig. 4. (PI. XII, (ii^s. fia, 01), pi. XXI, Ri;. 1:0.
The zocecia oval with a nund)er of very small seatlered ])ores and a very strongly arched basal surface with undulating, longitudinal stria-. The sternal area, which is of about Ihe same size as the ajjcrture, is provided willi 1— (> round or oval fenestra;, Ihrough which the margin of Ihe inner calcareous lamina can be clearly seen. The plainly visible frontal sinus is <)ccu])ied by 1 'A jiroxi- mal, rudimentary or veiy slightly develojied spines and further by the two large, distal ones which meet in a sulin-al line. The two latter sometimes show a small inner ca\ity. The anter of the aperture is semi-eliiplicaj, and its |)osler has a straight median j)ortion and two lateral parts oblicjnely ascending towards the hinge-teeth.
The lateral chambers form on eilher side a dislally directed, rounded, tri- angular expansion, the lop or the j)oint of which lies at the end of the su])ra- scapular chamber. The distance between the ends of llie two scapular chambers is in a unizocecial internode about the length of the inlernode, and the two lateral expansions form a distal angle of 120" — 140" with each other. The scapular chamber, which is everywhere developed as an avicularium with an extremely small mandible, has the form of a long, compressed lube, and con- trary to the case in all the above-described species an avicularium api)ears also on the adzoa'cial side of the mother-zoa'cium, where it is situated oj)j)osite the distal part of the aperture. It is here however considerably shorter and stands out almost vertically from the surface of Ihe zoociuin. The wing-like expansions formed by the lateral chambers are widest in the supra-scapular chand)er, from which they decrease in breadth proximally. The su|)ra scapular chand)er, which
247
has an ascending distal margin, is liigii, Irapezifornily pointed and provided with a rounded triangular opening on the Ironlal suil'ace in its proximal part. A similar, though somewhat smaller opening is found on the inlra-scapular cham- ber while the pedal chamber has a large, oval opening. Immediately to the proximal side of the above mentioned, vertically protruding aviculariuni there is a narrow, almost slit-like cavity, the adzoa'cial, infra-sca|)ular chamber of the mother-zocEcium, and in the bizod'cial internode only the pedal chamber on the adzoCEcial side of the daughter-zooecium is on the whole wanting.
The ocecium. The gonozo(rcium is a mother-zo<rcium, and its sternal area has 3 fenestra' aiul 3 spines, which iill the broad but low frontal sinus. The two larger distal spines, which have an inner cavity and a mostly uncalcified JVonlal wall, are proxidcd with a head-shaped, inwards and proximally bent terminal part, which is generally separated from the frontal sinus by a narrow fissure. The extremely small, unpaired spine is situated between the terminal parts of the two larger ones and separate these wholly or only i)artially. An avi- culariuni is wanting on the abzooecial as well as on the adzoa-cial side of the gonozoa^cium. On the latter side we find two widely separated lateral chambers, a rudimentary scaj)ular one and a larger pedal, while the scapular and the pedal chambers on the former side are represented by an auriculate process with one or two narrow pores.
The broad oa'cium is covered by the distal zocecium, the snuiU sternal area of which is provided with two extremely small fenestrse and two ribs or spines which meet in a suture, while the covering part of its frontal surface has a large, broad, l)i[)artite fenestra, which is bounded proximally by the distal, curved margin of the aperture and dislally by two curved lines that join centrally in a point directed towards the aperture. All the part of the ocecium to be seen through this perforation is [irovided with numerous, closely situated pores, the separat- ing, raised reticulation of whii'li ends in a number of tubercles and spinous pro- cesses. With exception of the proximal margin the part of the frontal surface of the ocEcium covered by the zoo'cium is provided with numerous, scattered, cyl- indrical spinous [irocesses.
Form of colony, ha this species two bizocx'cial internodes generally succeed each other, the latter springing from a daughter-zooecium.
I have examined a number of colonies from Port Phillip.
248
Pterocella carinata Busk.
{'nlenicella carinnta Busk, Voyage of Ballk'siiake, I, pag. 363, Catalogue of Marine
Polyzoa, (^heilosloniala, pag. 12, I'l. VI, figs. 4, ">, (j.
(I'l. MI, li'<. r>:\).
The zooecia iiuadiaiigularly oval, of a loundi'd li-iangular Iraiisvorsc set'tiou, lilt' basal surface consisting of two lateral halves meeting at an acute angle. This surface has slightly undulating, longitudinal striie and is pro\ided with a low median ridge, which in its centie rises inio a triangnlai-, s{)ine-like |)i'()cess. The sternal area is generally smaller than the aperture and |)r()vi(led with 3 fenestra-, and the extremely small frontal sinus is occu|)ied by two rudimentary spines. The anier of the aperture is semi-elli]ilic;d and its poster concave.
The lateral chambers form on either side a triangular, acute-angled e.xjian- sion, which is directeil sometimes straight outwards, sometimes a little distally and the vertex or point lies at the end of the scapular chamhei-. 'i'he distance between the ends of the two scapular chambers is in an unizoo'cial inlernode larger nearly by a half than the length of the internode, and the two lateral expansions form a distal angle of 180" — 270" with each other. The scapular chamber has an extremely small mandible and is shaped like a long, narrow, compres.sed tube, and the two adjoining, triangidar chambers have each a large, pear-shaped opening, which is larger in Ihe su))ra-scapular chamber, the frontal and distal walls of which are uncalcilied in their inner half. The i)edal clunnber has a long, oval opening. The mother-zoo'cium in the bizoo-cial internode is |)ro- vided with a small avicidarium, and proximally to the latter we lind as in P. ulnla a narrow boundary chamber.
The ooecium. The oa'cium as well as the gonozoo'ciuni and Ihe co\ering zo<rciuin bear a close resendjlance to the corresponding parts in P. (lUita and I shall accordingly limit myself to j)ointing out the most important diirercnces. On the gonozooecium the sternal sinus is much less developed and occupied by two likewise slightly developed spines, which, however, also have a teiuiinal i)arl bent inwards and proximallj'. The most conspicuous dilTerence is however found in the covering zoa^cium, which is jirovided with two lai-ge fenestra' separated by a rather broad longitudinal belt.
Form of colony. In Ihe small fragment IVom Napier, New Zealand, lliat I have examined, two bizoo'cial internodes nowhere succeed each other.
249
Calpidium Busk, char, emend.
The steiiuil (irca has 5 fenestrte disposed in a curve and an inner cryptocvsl lamina. The aperture, the anter of which is surrounded hy a strongly projecting margin, has a trilohed or triangular sinus ending in a [)oint, and is provided with two very strong hinge-teeth, projecting within the aperture. The rosette plates of the lateral chambers are placed in small rounded depressions and may therefore he looked u[)on as multiporous. The occlusion lakes place in a way similar to that in Sciiticella.
In the two species of this genus the lateral chambers occupy much more than one half of the surface of the single zoa'cia as well as of the bi- and tri- zod'cial inlernodes. They occupy especially the greater \y,\r[ of the distal as well as of the basal surface, l)eing separated here only by a number of elevated ridges, each furnished with a longitudinal furrow.
Calpidium ponderosum Goldstein.
Catenicella ponderosa Goldsl., Journal Micr. Soc. Victoria, 1880, pag. 63.
(t'l. X\I, figs. '):!— 5 0, t'l. Xtll, llgs. 1 n-1 d).
The zocecia are o\al and the sternal area, which is longer by at least a half than the aperture, is |)rovidcd with live large, ])ear-shaped fenestra separated by narrow ribs, in the marginal portions of which a generally strongly developed cryptocyst appears. Inside the sternal area is a large, obliquely oval cryptocyst lamina. The aperture is oblong and .separated by a constriction into an anter, the two lateral margins of which converge towards the constriction, and a tri- angularly trilohed poster. The sternal sinus is mainly preserved in the form (jf the small, triangular sinus of the aperture, but immediately on the proximal side of it an extremely short sutural line is seen, in which two very slightly devel- oped and somewhat [)rotruding ribs meet, ^^'ithin each of the two pi'occsses bounding the constriction we see a robust, cylindrically conical hinge-tooth, which however does not project freely into the aj)erture itself, when the latter is seen from the frontal surface. The anter of the aperture is surrounded by a large, obliquel}' protruding, bilobed, umbellate expansion, the two triangularly rounded lateral halves of which are separated by a broad, but low, obtuse-angled incision.
The lateral chambers. The scapular chamber is not everywhere developed as an avicularium, and the latter is not infrcciuenlly wanting on one side in the single zooccia as well as in the bi-zocecial internodes. The three other lateral chambers have a membranous roof and occupy a very large part of the surface
2o0
of the zocrciiim. They altaiii Ihi'ir i^rcalcsl extent on the basal siirfacc, on which they are .se])araled partly by a ralher liroad longitudinal hell, which is some- what concave towards the centre and hirnrcatetl in Ihe Ijizooecial joint, j)artly by the l)elt-shaped or ridge-liUe hileral branches, likewise concave and springing from the just-menlioned belt. The supra-scapular chamber reaches some way down the basal surface, luit a still larger part of it can be seen on the frontal surface, where the two chambers are separated by a narrow ridge passing tlown to the incision between the two umbellate processes of the aperture, the free edges of which form ])art of the boundary of the two chambers. From the proxi- mal end of each undiel the boundary ridge runs in a straight line towards the avicularium and then bends in an arch-shaped ridge, the distal ])art of whicli is parallel with the margin of Ihe frontal area of the avicularium. The infra- scapular chambers, which are the largest, form the greater \)m[ of the basal surface of the zott'cium and a large part of its lateral surfaces, and each cham- l)er is separated from the large, rounded quadrangular pedal chamber (fig. a b) by a ridge springing from the proximal end of the basal wall, which first passes obliquely distally and after another bending joins the sternal area. In the l)i- zoa?cial internode the greater part of the distal surface is occujjied by a large mendiranous chamber, whicli sends a triangular jiortion down the frontal as well as the Jiasal surface. This chamber is bounded on either side liy a low ridge, which runs from the ring of the joint lo Ihe incision in the biloliate marginal expansion of the aperture (hg. ae). A thick but rather short horizontal ridge, situated immediately on the distal side of the intermediate space between the two apertures (fig. 5 e), incompletely divides the cliamber into two parts, viz. a smaller frontal one and a larger distal and basal. Each of these communicates with the daughter-zoo'cium through a small rosette-plate with 2 — 3 pores, and Ihe entire chamber must be regarded as Ihe adzooecial, supra-scapular chamber of the molher-zoa'cium. The adzoo-cial infra-scapular chamber of the mother-zoo'ciuni is wanting, and with regard lo Ihe other chambers in the bizod'cial joint refer- ence may be made to the explanation of the plates.
The ocecium. The gonozooecium, which is only about half as high as the covering kenozoo'cium, is situated sometimes on a mothcr-zoo'ciiini, sonietinies on an inserted single zooecium. The sternal area, which is a little smaller than the aperture, is provided with 5 elongated feheslrae somewhat pointed at the di.s- lal end, which increase in length towards the centre but all reach nearly right up to the proximal margin of the aperture. Inside this row of openings, which reminds one of a visor, a very broad, rounded cryptocyst lamina is seen. On the other hand a frontal sinus and ribs or spines are complelelv wanting. The
251
greater part of the basal surface and of the lateral surfaces of the gonozonecium is occupied by two lateral chaml)ers, the proximal of which is the jjcdal, while the distal no doubt corresponds to the three distal chambers in an ordinary zooe- ciuni. Of these the former is of a (piadrangularly rounded form and enclosed on its distal as well as on its basal margin by the latter, which is triangularly kidney-shaped. On the basal surface both chambers of the lateral surfaces are separated by a central belt, which increases in breadth frontally and passes into a still broader bell separating the two large, long, bean-shaped fenestric of the kenozoa^cium, which may sometimes meet on the frontal surface, sometimes be separated by a narrow central belt. Inside each of the two fenestraj the ocecium is provided with a broad belt of closely situated pores, the separating reticulation of which terminates in a number of luliercles and spinous processes and these structures may also be present partly in the marginal portion of the two fenestrse partly along the distal margin of the aperture. On the top of the kenozocvcium we find an arrow-shaped, mend)ranous chamber, which is sharply pointed fron- tally and deeply indented l)asally and the basal half of which is incompletely divided into two i)y a longitudinal ridge springing from the indentation. The frontal end of the ridge often terminates in a strong process, and on either side of it we find a group of uniporous rosette-plates.
Form of colony. The alternation of uni- and bi-zoci'cial internodes is regular except in the lateral branches, which often spring from a daughter-zoo'cium and which in every other bizoiecial inlernode bear only bi-zoa'cial joints (uj) to ')). I have liowever sometimes seen such a l)ranch completed by a single zoii-cium.
Of this species a colony from Tasmania has kindly been placed at my dis- posal by Dr. Harmer.
Calpidium ornatum Busk. Voyage of Rattlesnake, pag. 364, (Catalogue of Marine Polyzoa, Cheilostomata,
pag. 15, PI. XII, XIII. (PI. XX, figs. 11 a-11 f). The zocecia are oval. The sternal area, which is longer than the aperture by about a half, is provided with 5 fenestra? of very different size, viz. two small distal ones, two larger median and one the largest proximal. Inside the sternal area we find an oval cryptocyst lamina, and further each perforation is provided with a well-developed cryptocyst, which in older zoa>cia may hide the inner lamina entirely. The elongated aperture has a constriction somewhat |)roximally to the centre, and here we find two robu.st, conical, cylindrical hinge-teeth con- verging proximally, of which the terminal part only projects freely in the aper-
252
ture. The poster of Ihc aperture is Irilohcd, while its anter, which is surrounded ])y a strongly protruding, not bilohate margin, has two proximally converging lateral margins.
The lateral chambers, hi every internode llie scapular eliamher generally seems to he developed as a small triangular avicularium on the outside of the two daughter-zod'cia, whereas no other avicularia occur. The correspoudiug sujjra- scapular chamber appears on the distal surface as a small, triangular cavity, which is hut incompletely seiiaraled from the cavity occujiying the remaining part of the distal surface. It is moreover continued into a long, narrow depres- sion on the outside of each daughter-zocrcium. To understand the form and ex- tension of the other chambers we must lirst study the system of jirojecting ridges, which separates them. On regarding a tri-zofrcial internode from the distal surface (lig. lie) we see, thai the latter is divided into two lateral halves by a longi- tudinal ridge, which passes from the distal margin of the aperture of the central zoa'cium to the annular facette of the joint and is continued from the basal side of the latter along the centre of the basal surface. xMoug the frontal margin of the distal surface a continuous transverse ridge may ap[)ear, situated vertically on the just-mentioned longitudinal ridge. The transverse ridge may pass beyond the centre of the apertures of the two lateral zou'cia, but in many cases we tind in its place two shorter or longer .separate transverse ridges, which are not joined on to the longitudinal ridge. The greater part of llie distal surface is occupied by two large lateral chambers covered by a membranous roof, which we uuiy for the present term the distal chambers ami which are each provided with a transversely situated, deep pit with (5—8 pores. On the frontal side of these, two long, |)ointed cavities are seen between the three zoojcial apertures (fig. 11a), each commuuicating through a [\\[ with 1— ;$ pores sometimes with the daughter- zoG'cium, sometimes through a corresponding pit with the mother-zoa'cium as well. Considering the two daugbter-zoa-cia as the scajiular chambers of the mother-zooecium we must regard not only the two distal chambers but also the triangular ones on the frontal side of them as re])re.senling the supra-scapular chambers of the mother-zoa-cium. From Ihe |)ro\iuud half of the basal, median, longitudinal ridge two curved, more or less strongly ascending ridges start on either side, of which the proximal one forms the boundary of the sternal area for some distance (lig. lid), namely, opposite the nu'dian fenestra, and terminates in a small process just proximally to Ihe avicularium. The cavity, bounded partly by this ridge, partly by the median ridge and by Ibe nuugin of the sternal area, is the pedal chamber and on the frontal surface it has a very deej) nniltij)orous rosette-plate (tig. lid, d. 1\'). The distal of the two lateral ridges.
253
which does not reach the ninrgin, gives off from its proximal i)art a l)rancli di- rected distally and then hending almost reclangiilarly outwards lo join the supra- scapular chamher. The two large lateral chamhers, occupying the greater part of the I)asal surface of the zo(rcium and incompletely divided into two, are the two infra-sca[)ular chamhers (fig. 11 d, d. Ill), and each of their two parts has a separate pit with pores, of which a very small one is situated near the avi- cularium and a large, deep, ohlong, multiporous one distally to the proximal lateral ridge, hi the hi-zo(i'cial joints digs. 11 e, 1 1 f ) the hasal surface of the zoa?cium has a similar structure on the lateral half corresponding with the daughter-zon'cium, whereas on the lateral half corresponding with the mother- zocecium we find instead of the hranched distal ridge an unhranched one situated much higher uj), which together with the median ridge forms the houndary of the undivided supra-scapular chamber. We find a similar contrast with regard lo the infra-scajjular chamher, which is also undivided in the half hclong- ing to the mother-zoa'cium. A longitudinal section tlirough a Iri-zocecial joint dividing it into a frontal and a hasal half shows that the two lateral surfaces of the mother-zod'cium join the daughter-zod-cia in the whole of their length and communicate with them through two groups of uniporous rosette-plates, a distal and a proximal group. Thus a daughter-zou'cium occupies the space which is otherwise occupied J)y the scapular and the pedal chamher, and we cannot therefore expect to find oilier chambers than llic supra-sca|)idar ones on the mother-zooccium or on the adzooecial side of llie daughter-zod'cium. Accordingly the two large cavities, which we called the distal chamhers, together with the two small triangular cavities distallj' lo the avicularia, must be regarded as llie supra-scapular chamhers.
OcEcia have not been found.
Form of colony. The colony is composed principally of tri-zocecial internodes, and a bi-zocecial internode is found only at the base of each fresh branch. It is less branched than in the other species of this family and we may find up lo lli separate internodes in one bifurcation.
I am indebted to Miss Jelly for a fragment of lliis rare species from Victoria.
Catenaria Savigny. Catenicella Blainville, Vittaticella Maplesf. Calloporella Mac Gillivr. '
A sternal area and an inner cryptocysl lamina wanting and the frontal surface only provided with extremely fine, scattered pores. The aperture, which has a
' 7i;, p. s.
254
concave, thickened, prolnuling, proximal rim, has two well-developed, conspicuous hinge-teetli and is closed finally hj' tlirce (one distal and two proximal) calcareous processes, springing from its inner margin and meeting in the centre. The pedal chambers, at any rale those of the single zooecia and the molher-/o(iL'cia, are very long, narrow and their frontal wall is cpiite uncalcified.
The peculiar occlusion we lind in this genus is similar to that in Mclicertites Roiiana pointed oul by \\'alers'. Here also il is brought about by means of 3 — 4 calcareous processes, which meet in the cenlie of the aperture. If there are three, which is usually the case, they are however di.sposed in a dill'crent way from in the species of the genus Calenaria, as in the above species theie are two distal and one proximal. The type-species of this genus is C<d. Conlci And., of which Mr. Waters- has recently given a description.
Catenaria formosa Husk.
Catenicella formosa Busk, Voyage of Rattlesnake, I, pag. ;(()(), Catalogue of Marine
Polyzoa, Cheilo.stomata, pag. 9, PI. VII, ligs. 1, 2.
(IM. XXI, li{^. 3 a, I'l. XIIl, lig. 2 a).
The zooecia, the breadth of which may be contained l'/2 times in the length, are of a robust, angularly oval form, and the boundary between the flat frontal wall and the arched basal wall is formed on either side by a distinct marginal ridge. The aperture is provided with a proximal, strongly concave margin.
The lateral chambers. The scapular chamber, which in most zooecia seems to be developed as an avicularium with a small mandible, is large, compressed, somewhat ascending and protruding almost straight outwards, being only slightly inclined frontally. The supra-scapular chamber is a low, narrow cavity, provided with a membranous roof in the whole of its length. The infra-scapular chamber is a small, wholly frontal cavity with a circular opening, through the centre of which the septum between the zocrcium and the avicularium can be seen; and the pedal chamber, which attains an unusually large breadth, though but seldom more than half the length of the zocrcium, is likewise frontal and has its start- ing point somewhat i)roximally to the opening of the infra-scapular chamber. It is considerably smaller on the daughter-zooccium than on the other zoo'cia and especially very small and oval on its adzonecial side. In the bizotrcial joint we find a pear-shaped or oval boundary chamber (m. III). The adzoircial side of the daughter-zoa'cium is generally i)rovide(l with an avicularium and the ad-
' 108 ;i, p. .52. ■-' ll(!,i, p. 130.
255
zooecial side of the mother-zooeciuin with a membranous, supra-scapular chamber (m. I).
The ocecium. The gonozooecium, the aperture of which is provided with a more strongly projecting but less strongly thickened under-lip than the ordinary zorecia, is a single zocecium, which may spring from a mother-zooecium as well as from a daughter-zoa>ciuin. In a colony from Victoria three gonozoa'cia may appear immediately succeeding each other. The scapular chamber is developed as an avicularium with a small mandible, which is only visible from the side. It is very long, narrow and may sometimes almost reach the top of the oa'cium, with the covering zod'cium of which it has coalesced. When seen from the frontal surface the two almost i)arallel avicularia have a (juadrangularly colum- nar appearance, and each has a supra-scapular chamber with a membranous roof on the top and on the basal surface. The covering zocrcium, which is other- wise of the ordinary structure, has a large, quadrangularly or pentagonally rounded fenestra distally to the aperture of the gonozod'cium, and the on'cium shows on either side a broader or narrower, arch-shaped Jjelt, which is quite white by reduced light and reddish by strong reflected light, originating from an incomplete calcification. Around it a rather large area is seen showing the boundaries for the coalescence of the oa»cium with the lateral walls of the covering zod'cium.
Form of colony. The alternation of uni- and bi-zoa-cial inlernodes is regular, but rows of single zoa-cia may also appear.
Colonies from Victoria (Miss Jelly).
Catenaria elegans (Busk). Catenicella elegans Busk, Voyage of Battlesnake, I, pag. 361;
Catalogue of Marine Polyzoa, (Iheilostomata, pag. 10, PI. IX,
Challenger, Zoology, Vol. X, Part I, pag. 12, PI. I, figs. 2, 3, 5.
(PI. XXI, Tig. 2 a, PI. XIII, figs. 3 a, 3 b).
The zooecia, the breadth of which may be contained 2", times in the length,
are elongated, slender, with evenly arched sides without marginal ridges and
with a frontal surface less arched than the basal surface. The proximal nuugin
of the aperture is not verj' concave and forms almost right angles with the lateral
margins.
The lateral chambers. The scapular chamber is everywhere, also on the ad- zoppcial side of the daughter-zoa'cium, developed as an avicularium, which is directed almost straight outwards, but with a slight basal turning. The straight or slightly uiched roof forms an approximately right angle with the longitudinal
25(5
iixis of llu' zodriimi. The supra-scapiilni- clKimlxT is a very small, low cavity willi a lriani;ularly rounded o|n'iiing situated distally to tlio inner part of tlic aviculariuni. The inlVa-seapular chaniher lias an oval oj)enini^ and is situated proxinially to the I'ronlal wall of the aviculariuni. It is principally in coninuini- calion with the zotrciuni, IVoni wliicii it is only se|)araled by the small proximal wall of the aviculariuni. 'I'lie narrow, likewise rrontal, pedal chamlier. which in the single zod'cia may attain hall' the length of the latter, is situated proxinially and a little Irontally to the infra-scapular chamber. There is a small, oval bound- ary chamber (m. HI) on the bi-zoo-cial inlernode, and the pedal chamber on the adzo(rcial side of the daughter-zoa'cium is very short, sometimes merely oval.
The ooecium. The gonozonecium is as in the preceding species a single zoa*- cium. The proximal part of its operculum is covered by a thin, labiate process with a straight margin, and its avicularia differ from the ordinary zon'cia in having the mandible situated in their roof, so that it forms a right angle with the longitudinal axis of the gonozocecium, while in the ordinary zo(t>cia it is parallel with this axis. The covering zocrcium has distally to the aperture of the gonozooeciuni a rather large, irregularly rounded fenestra, on either side of which we find a long curve of u|) to 20 small, round spots, which corresiiond to the continuous belt in the i)receding species.
Form of colony. Uni- and bi-zoo'cial intcrnodes alternate in such a way, that two bi-zo(ecial internodes are often separated by two or several single zooccia.
Colonies from Twofold Hay, St. 16:5 A, Challenger. The form described essen- tially corresponds with Ikisk's typical specimen from Bass Straits, which how- ever differs in having larger, somewhat ascending and somewhal Irontally turned avicularia.
Catenaria cornuta (Husk).
Catenicella cornuta Husk, Voyage of Hattlesnake, I, pag. 'MM, Catalogue of
Marine Polyzoa, Cheilostomata, pag. 11, HI. X, figs. 1, 2. ."i.
(V\. Xm, figs. 5a, .■)!), 1^1. XXI, Hi;. 1 a).
The zooecia, the breadth of which may be contained about twice in the
length, have a frontal surface almost as strongly arched as the basal surface and
on either side a narrow marginal ridge, which bounds the pedal chamber basally.
The lateral chambers. In the examined colonies it is only in a smaller
number of zoiecia that the scajiular chamber is on one side developed as an
aviculariuni, directed outwards and somewhat basally. Such a chaml)er may be
found not infrequently on :, daughter-zoacium, the corresponding mother-zouicium
257
of which bears an onecium, but otherwise it does not seem to appear in bi-zooe- cial internodes. The aviciilaiium has a somewhat ascending roof and a robust beaked hook. It communicates on its basal side with an extremely small snpra- scapular chamber with an oval o])ening, and forms a deep sinus together with the trapeziform infra-scapular chamber, which has a truncated conical process and a rounded frontal opening. When not developed as an avicularium the scapular chamber appears as a generally long, compressed, conical, spine-like process, which ascends obliquely and is directed basally and on which the supra- scapular and the infra-scapular chambers are indicated by a perforation on each of its two surfaces. The proximal part of this process, which corresponds to the infra-scapular chamber, is however not infrequently conically projecting and separated from the other part of the spine by a deep sinus. The pedal chamber is of moderate breadth and its ojjening can only be seen when the zoa-cium is regarded from the side. It reaches right up to the infra-scapular chamber and its length is two-thirds of the zoacium. On the bi-zooecial internode there is a small, oval boundary chamber (m. III).
The ooecium. The gonozorecium is always a mother-zonecium, and the ooecium is covered by a kenozoa'cium. The latter generally ends in a shorter or longer conical spine, which must be regarded as an unpaired scapular chamber. More rarely we find a small cavity with a membranous roof. The kenozoo'cium, the frontal wall of which is sometimes whole, sometimes provided with a median pore, has on either side a pedal chamber, which is placed on the basal surface and is pi-ovided with 3 — (i iincalcificd rosette-j)lates, disposed in a single or a double row. The proximal part of the operculum of the gonozooecium is covered by a thin, erect under-lip, and on the abzooecial side we find a spine-like scap- ular chamber opposite to the aperture, whereas the abzoa?cial scapular chamber on the corresponding daughter-zod'cium is most often developed as an avicul- arium. In the examined colony the mother-zoa'cium may be developed as a gono- zoo'cium in up to three succeeding bi-zotiecial internodes.
Form of colony. In this species uj) to four bi-zoa-cial internodes often succeed each other, and rows of single zoa?cia only are never seen.
Colonies from Port Phillip (Miss Jelly).
Strophipora Mac Gillivray.
A slernal area as well as an inner cryptocyst lamina are wanting in the zo(i'- cia, and the whole of the frontal surface is covered by the two infra-scapular chambers, which are separated by a narrow longitudinal ridge in the central line of the frontal surface. A little proximally to the aperture we find a median
17
258
pore surrounded by a ring Nvliich is continuous with the longitudinal ridge. The aperture is provided with well-developed, distinct hinge-teeth and has a proximal concave margin.
Strophipora Harveyi Wyv. Thompson. Catenicella Harveyi Wyv. Thompson, Natural History Review, V, 1858, p. i;57. — — Wyv. Thompson, Proced. Dublin Univ. Zool. and Botan.
Associat. I, p. 81, PI. VII, figs. 1, 2. Strophipora Harveyi Mac Gillivray, Transact. R. Society of Victoria, 1895,
Vol. IV, p. 17, PI. II, ligs. 9—12. (PI. XXI, figs, fi —6 f). The zooecia are of an oi)long, (juadrangularly oval form, nnd Ihe frontal sur- face, which is less strongly arched than the basal surface, is most strongly arched immediately on the proximal side of the aperture, from which it descends to- wards the ])roximal end.
The lateral chambers. The scapular chamber is everywhere, except on the adzooecial side of the mother-zoo'cium, developed as an avicularium of medium size at least, which is always directed so much towards tlie frontal surface that the surface of the mandible can l)e seen, when the zoircium is regarded from this side, and it may sometimes be altogether frontal. It has generally a some- what ascending roof and may vary considerably in size, and in the single zoo'cia at least a somewhat curved, rib-like thickening springs from its proximal end. The supra-scapular chamber is a large, more or less ascending, membranous, pointed cavity, while each half of Ihe frontal surface is occupied by a large infra-scapular chamber, which communicates with Ihe zoo'cium through a longi- tudinal row of 4 — 5 very scattered rosette-plates. The Iwo chambers are .sei)araled by a longiludinally furrowed, narrow median ridge, and eacJi of them is se|)a- rated from Ihe adjoining pedal chamber ])y a similar lateral ridge. Each of Ihem is generally separated from Ihe sujjra-scapular chamber by Iwo low ridges, Ihe starling point of wliich is on a level with Ihe Iransveise ridge of Ihe avicuiariuni and which pass, one to Ihe margin of the aperture, the other to Ihe lateral ridge. The membranous wall of the infra-scapular chamber runs out on each side into two conical expansions, which are situated clo.se to the ai)erture, and a couple of similar expansions may also ;ippear in Ihe distal |)arl of Ihe basal surface. The two pedal chambers occupy the entire basal surface of the zoa'cium and are likewi.se separated by a longitudinally furrowed median ridge, while again each chamber is divided into Iwo unecpially large parts by an exlremely narrow, low, compressed, longitudinal ridge, which appears in its outer half and serves to
259
support the nieinhranous \v;ill. Tlic losette-plalos are disposed in a very scattered row near tlie lateral ridge.
With regard to the appearance of the various lateral chaud)ers on the hi- zocecial internode reference may be made to the figures and the accompanying ex- l)lauation of the plates.
Ooecia were not found in liie fragment examined.
Form of colony. In the examined fragment two bi-zooccial inlernodcs often succeed each other and also rows of up to four single zoa?cia.
Of this species I have had the opportunity of examining a dry fragment of Wyv. Thompson's original s]iecimcn from Bass Straits (British Museum).
The genera Stenostomaria and Ditaxipora set np by Mac Gillivray' arc closely related to Strophipora, and in both of them the whole or almost the whole of the surface of the zooecium is occupied by the lateral chambers. Both genera contain only a single species, and in Ditaxipora internodia Waters, the internodes of which consist of 7 — 8 zooecia disposed in two alternate rows, the greater part of the basal surface, judging from the figures, is formed by a single (outer) pedal chamber. The same author has founded the genus Microstomaria - on a single bi-zo(Kcial internode, and the longitudinal ridge represented in tig. 29 seems to show that this genus must also be related to Strophipora.
Family Onchoporidae.
The slightly calcified zoa'cia, the frontal surface of which is covered by a closely adhering (chitinous?) membrane, are generally provided with a number of superficial, uni- or multiporous rosette-plates, which are most often situated in the distal part of the zooecium. The distal wall, which is bent from side to side, has a number of uniporous or one multiporous rosette-plate, while the dis- tal half of each lateral wall has a single multiporous plate. No aviciilaria. The strongly projecting hyperstomial oa'cia, the aperture of which may be closed by the zooecial operculum, consist of two membranous (chitinous?) layers, between which there is a cryptocyst layer, which springs from the distal wail. Free,
branched colonies.
Synopsis of the genera.
1) The compensation-sac opens outwards through a crescentic ascopore.
2) The zooecium consists of three dilTerent segments: a short proxi- mal, a long stem-like middle and a widened distal one; (the operculum compound or simple) Calwellia W. Thomps.
' 76, pp. 16 and 22. ' 76, p. 18.
17*
260
2) The zooeciuni not consisting of tlirce different segments:
3) A simple operculum; the ocrcia with a couple of proximal, free, rib-like^processes Onchopora Busk.
3) A compound operculum; the ocrcia without free, rib-like pro- cesses Onchoporellu Busk.
(Ichthyaria?)
1) The compensation-sac does not o\)en outwards through a pore, hut immediately on the proximal side of the operculum . Onclioporoides Ortmann \
Onchopora Sinclairi Busk. Onchopora Sinclairi Busk, Quart. Journ. Micr. Sci., Vol. 5, 1857, pag. 192,
PI. XV, figs. 1—3. — -- Busk, Challenger, Zoology, Vol. X, pari I, pag. 103,
PI. X, fig. 4. Calwellia Sinclairi Harmer, Quart. Journ. Micr. Sci., n. s. Vol. 4(5, pag. 312,
PI. 18, fig. 60. (PI. XIII, figs. 7 a-7 h). The zocecia, which only slightly increa.se in lireadth from their proximal, somewhat narrowed end towards the aperture, have a little proximally to the latter a linearly crescentic ascopore with frontally directed concavity and a crenu- lated proximal margin. A sulural line connects this ascopore with the aperture, Ihe two curved lateral margins of which converge a little proximally. The aperture is surrounded by 6 ro.sette-plates. Of these the two smallest have 1—2 pores each and are situated between the aperture and the crescentic ascopore. The other four, which are very elongated and each provided with 3, more seldom with 2—4 pores, surround the remaining part of the aperture. There are more- over 5 round pores, ot which three are situated among tJie four elongated rosette- plates and each of the other two between an oblong and a round roselle-plate. The distal wall is provided with numerous uniporous rosette-plates, and the dis- tal half of each hileral wall with one extremely oblong multiporous plate.
The ooecia are large, strongly arched and in part strongly luberculated. They are provided with rounded ridges, arranged in the shape of a fan and separated by impressed lines. On the basal surface a more thickened, triangularly oval por- tion is .seen (fig. 7 f), on either side of which we find a few larger hollows separated by rib-like Ihickenings, which spring from Ihe frontal wall of the just mentioned more thickened portion. From the proxinud part of the latter a free,
' 87, p. V>.
261
rib-like process starts on either side. These processes are situated immediately within the jiroximal margin of the eclooa'cium and they have a terminal por- tion, whicli is bent upwards a little.
The colonies form richly branched tufts, and the narrow columnar bifurcate branches have four longitudinal rows of zod'cia.
Judging from descii[)tions and figures the forms hitlierto described under the name o( Sinchiiri present several dilferences from the form here described as well as from one another, and only a comparative examination will show how great an importance we ought to attach to these dilferences. For this reason I have retained Husk's name for the form examined by me, which originates from Akaroa Harbour, New Zealand (Suter).
Under the names of 0. picoensis and <). diiiiuildi Jul lien' has described two species, which seem to me to i)e very little different. In these the two small ro- sette-plates between the aperture and the crescentic ascopore are said to be re- placed by two small, round avicularia. As, however, avicularia have not hitherto been made out with certainty in this family, this information needs further con- firmation, as Jul lien's figures are not convincing.
Onehopora dentata Mac Gillivr. Urceolipora dentata Mac Gillivray, Transact. Royal Soc, Victoria, Vol. 21, 1884 (1885), pag. 109, P\. I, fig. 1. (PI. XIII, figs, (ia, 6 b). The zocecia, which increase greatly in extent from their narrow proximal part towards the distal end, are somewhat compressed, strongly archeil and when seen from the side of a triangular outline. Along the distal margin they are pro- vided with r^ short, widely separated spines, which are rounded at the end and surround the aperture. There are 6 transversely oval uniporous rosette-plates, of which two are found between the aperture and the ascopore, while each of the four others is situated between two spines. The operculum is almost semi- circular with nearly parallel lateral margins, and the ascopore, which is con- nected by a sutural line with the aiierlure, is but slightly curved with proxi- mally directed concavity. The distal wall, which is bent from side to side, is provided with a number of uniporous ro.sette-plates and terminates on either side in 3 — ii digitiform prolongations, of which the frontal is the longest. The distal half of each basal wall has a large, pear-shaped, multiporous rosette- plate.
' 48, p. 52—53, m. IV.
202
The ooecia are in nil essentials of a similar I'urin ami slriictiire as in the preceding species; hul llie Iwo lice, rih-like i)rocesses are not bent like a hook.
The colonies are richly branched, bilurcated and wilh Ihe zorecia arranged in two rows, which have Ihcir apertures turned in an opposite direction.
Colonies from Victoria.
Calwellia bicornis W. Thonips. '
(I'l. XIII, ligs. 8 a— 8 c).
The zooecia are opposite, disposed in pairs and in such a way that Ihe di- rection of each pair is vertical to that ol' the preceding or succeeding pair. While the distal terminal parts of a pair of zotrcia meet wilh Iheir basal sur- faces, the two corresponding proximal stem-like parts, which are of a triangular transverse section, are on the contrary separated in the whole of Iheir length by the terminal parts of the proximally situated pair of zott'cia (fig. 8 c), each of them touching with its inner edge one end of the separating wall, which the two just-mentioned basal surfaces share in common. No rosette-plates are found in this wall, but there is a multiporous rosette-plate (fig. 8 a) in the distal end of each stem-like part on each of the two surfaces which are bent towards each other at an angle, and an inner communication is thus brought about between the stem-like part of the distally situated pair of zooecia and the distal end of Ihe proximally situated pair. Each stem-like part ends proximally in a small, sharply defined, rounded portion, and proximally to it is seen the narrow, angul- arly bent distal wall (figs. 8 a, 8 b) which is furnished with a multiporous ro- sette-plate centrally. The strongly arched distal portion of the zoa>cia, which greatly increases in breadth from its very narrow proximal part lowards the dis- tal end, is on either side of the aperture provided with a short, robust spine, which is rounded at the end. The transversely oval aperture has a compound operculum. A sutural line connects it wilh the transversely oval crescenlic asco- pore, which has a slight distal concavity. On Ihe proximal as well as on the distal side of the aperture we find two widely separated, transversely oval, uni- porous rosette-plates.
Ooecia are wanting in the examined colonies; butWyv. Thompson's figure shows that they are provided with finely, transversely striated ridges disposed in the shape of a fan. They arc present in some colonies of C. (jracilis Maples, ori- ginating from Bass' Strait, which species differs from C. bicornis for one thing in having a simple o])crculum with a straight proximal margin. In this species also
101. p. <J2. in. I.\, liys. 2, 2i\
263
the ooccia have a similar structure and laciv the two free, ril)-like processes found in the two above-described Onchopora species. Colonies from Hawlvcs Hay (Miss Jelly).
Onchoporella bombycina (L.) Busk. Carbacea bombycina Busk, Catalogue of Marine Polyzoa,
Cheiloslomata, pag. 52, PI. 48, figs. 4—7. Onchoporella bombycina Husk, Challenger, Zoology, Vol. X, Part I, p. 104.
(t'l. Mil, ligs. 9a-9j).
The zooecia are elongated, generally liexagonally rounded, and the large aper- lure has a semi-elliptical anter and a broadly rounded, ol)ii(]uely (nilwards turned [)osler, which latter is sejjarated on either side from the former hy a distinct hinge-tooth. Outside each hinge-tooth we lind a ralher shorl, cyiindrically coni- cal .spine, and a very small spine is situated at the distal end of the zoa'cium. The large, widely open ascopore is made semilunar by a triangularly rounded tongue projecting into it dislally, and the two lateral margins of this tongue are continued into two sutural lines, which diverge toward the ai)erture and sometimes can be traced to the corners of the poster. The ascopore seems therefore to be the remains of a triangular primary sinus, the greater part of which is later filled up. In the narrow marginal portion between the aperture and the distal end of the zocecium we find 2 — 4 rosette-plates, which have altogether up to 6 pore- areas. If there are only two plates, they are very elongated and provided each with 2 — 3 areas. On the proximal side of the aperture 1 — 6 pore-areas are found along each lateral margin. They are situated in a longitudinal row and may be distributed on f— 4 rosette-plates, of which the longest hitherto found contain 4 areas. Most often an uneven number of pore-areas are found on the two sides of the same zoojcium and the larger number is generallj' present on the side, which is turned away from the central line of the branch. The largest number of pore- areas is generallj' found on the" outer side of the marginal zooecia.
The distal wall is bent from side to side and on either side terminates in a pointed portion. Along its basal margin we find a rather dense transverse belt of uniporous rosette-plates (tig. 9 g), while the distal half of each lateral wall is pro- vided with an oval, multiporous plate.
The ooecia are large, strongly arched, with low, transversely striated, radiating ribs. The basal surface is provided with a more thickened central portion with rib-like processes, and the proximal part of the eclooa>cium is calcified for a short distance on either side of the aperture.
The colonies arc Flustra-like, one-layered, richly branched, with rather short
264
segments and the margin ol" the colony is lormed by a row of kenozocecia. In Ihe hitter a deposition of calcareous matter takes place, which starts from the inner wall and finally fills the whole of the kenozod'cinm with a strongly tuhcr- culated, lobed, marginal thickening divided as if in transverse bells (figs. 9 e, 9 g). Radical fibres may issue from mulliporous rosette-plates on the basal surface of the colony (figs. 9 c, 9 d).
Colonies from South Africa.
'Carbaseci'i Mose I eiji Busk \ which undoubtedly belongs to this family but seems to have no ascopore, is by Ortman'- referred to a new' genus Onchoiioroides; it seems to have no median pore. Tlie horseshoe-shaped marks, wiiich can be seen in most zoa-cia in Busk's drawing, unquestionably originate from the basal walls of the beginning ooccia.
Family Euthyroidae n. 1.
The slightly calcified zocrcia have no pores and no covering-membrane. On the proximal side of the operculum they are provided with 1 — 3 pairs of fiat, hollow spines, which meet in the central line and cover the entrance to the compensation-sac. A compound operculum. Lateral walls with multiporous ro- sette-plates. Independent aviciilaria may occur. The ectoooecium of the hyper- stomial oa'ciiiin is provided with a pair of large fenestrse. Colonies free, branched, Fluslra-like.
A single genus: Euthyroides Harmer^
Euthyroides Jellyae n. sp.
(PI. XVI, ligs. ,Sa-8e).
The zocBcia are elongated, rectangular, slightly arched, with a slightly curved distal wall, which has witliin its basal margin a zigzag belt of (12 — 14) snuill, uniporous rosette-plates. The distal half of each lateral wall with 2 — 3 multi- porous rosette-plates. The aperture, which in the non-oa>cia-bcaring zoo'cia is provided with two distinct, rounded hinge-teeth, has a quadrangularly rounded form, its anter being composed of three curved lines meeting at right angles, while its poster forms a more strongly curved line which is generally bent in the form of a saddle (fig. 8 d). The operculum is of a corresponding form and provided with a chitinous thickening along its proximal margin. Immedialelj' on the proximal side of the operculum we find between the two hinge-teeth a very small
8, p. r>(). - 87, p. 12. ' 111, p. -.'SO.
265
membranous porlion, which is covered by two pentagonal, hollow spines, that meet in a suture. Hetween their opercular margin and the hinge-teeth there is a small sinus, and their I'orm is subject to some variation so that the suture be- tween Ihem may be sometimes shorter, sometimes longer. At an earlier stage these sjjines are not yet present, and the operculum (hg. .S b) at this lime is proximally surrounded by a calcareous belt, se|)arated by a yellowish, glisten- ing margin from the rest of the calcareous wall. A resorption of the calcareous mass proximally to the operculum soon commences however, and the two sjjines gradually dcvelo[) and cover the decalcified porlion. Such a [)rocess does not seem to take place in E. episcopalis.
The ooecia are high, strongly arched, almost ovil'orm, and the ectoon'cium has on either side of the central line a large, triangularly rounded fenestra, hi- side the narrow central belt there is a longitudinal ridge joining the endooo'cinni. The ooecia-bearing zocecia have no distinct hinge-teeth and contrary to the case in E. episcoj)(ilis there is but one pair of spines proximally to the operculum.
Avicularia. On the examined fragment a single, independent, elongated and lyre-shaped avicularium was found, the wholly calcified subopercular area of which showed a distinct sutural line along the centre, while its opercular area was provided with a strongly developed cryptocyst perforated by an oblong open- ing. The mandil)le has at its proximal part two small, pointed lateral processes.
The form of colony seems to have been free, laminate or broad and Flustra- like. Tiie small, dried fragment that I have examined of this form shows ai)out 50 rows of zooecia. It originates from North Australia and was given me by the late Mr. C. N. Peal.
The two species of the genus Eiilhijroides dilfer so much from all other asco- phorous forms, that it has been necessary to refer this genus to a new family, the nearest relatives of which must undoul)tedly t)e sought in the family Cribri- liiiiilac and especially in the genus Eigulina. The two species agree with this genus in regard to the structure of the rosette-plates and the presence of two large fenestra' in the oa'cia. The avicularium found in E. Jcllijde quite corre- sponds with that found in the Fiyiilina species, and in most of the latter the form of the aperture is similar to that in the two just-mentioned species. There are other points of similarity, such as tlie well-developed hinge-teeth and the spines which are provided with a pore. In /•'. chlilhrididta Waters the number of spines may sometimes be reduced to 3 on each side. — With regard to the struc- ture of the ooecia the tertiary Membraniporellti leiuiicosla described by Mac Gillivray ',
' 70, p. 56.
266
which I must also refer lo I'i<iiilin<i, hems a closei- resemblance to the Eiilliij- roides species than any of llie oilier Figiiliiid species. — Tlie author does not mention avicularia, hut at tlie top of his hgure he has drawn something which is undoubtedly an independent avicularium, the opercular area of which is pro- vided with a strongly developed cryptocyst.
Family Crepidacanthidae n. f. Crepidacantha nov. gen.
The zod'cid, whose aperture has strong liinge-teeth and a compound well-chi- tinized operculum, are in the proximal half provided with i)- 12 very long mar- ginal spines and with 8 — 11 small iiniporous pore-chambers alternating as a rule with small intermediate chaniber.s, each of which has an uncalcified spot (a mar- ginal pore) in its roof. Two frontal vibraciiUi without a cross-J)ar. The hyper- stomial, almost free oaria consist of two calcified layers, of which the ectooa'ciiim is provided with a number of pores.
C. Poissoni Anil., \ar crinispina n.,
Flustra I^oissonii Audouiu, Description de I'Kgypte,
Hisloire natnrelle, Tome I, explication sommaire des Planches, pag. 240; Polypes, PI. 10, figs. 5i — 52. Lepralia Poissoni Jelly, A synonymic catalogue of the recent marine Bryozoa, 1889, pag. liil. (Figs. 1-6). The zocEcia, which have a broad, roundedly rhombic outline and are j)i()vided with narrow, transversely ovate, marginal pores (fig. 1), are very convex, and the frontal wall shows a number of finely undulating, dendrilical, sutural lines. The aperture, whose distance from the distal end of the zoircium is about as large as its own length, is longer than broad, provided with a prominent anter and con- stricted in the proximal third by two triangular, proximally converging processes within each of which is seen a strong conical hinge-tooth. The proximal margin of the aperture is provided with a broad, roundeiily trai)eziform [)rocess on each side of which there is a small rounded sinus. The o|)ercuhim (fig. .')) which is well-chitinized, punctate, of a yellow colour and disfincliy sei)arated i'loiii the compensation-sac, is provided with a partly developed oi)erciilar arch consisting of two lateral ridges, hi the distal half of the zoax-iuin there is found 9 — 12 very long and thin, marginal spines and a similar number of small (piadrangular uni- porous pore-chambers (figs. 2 — :{) alternating as a rule willi a similar number of small inleriiiediale cliaml)ers (ligs. 2—3), each of which is in connection
2(57
with one of Ihe al)ove-incnlionc'(l iiiai
pores. Each spine is placed tlistally
to the opening of a pore-chamber. The small intermediate spaces which are generally (piadrangiilar or triangular may sometimes be almost slit-shaped, and not rarely they are lacking between the 2 — 4 distal pore-chambers. This seems lo be the rule in the ocrcia-bearing zoa^cia, and sometimes the two outermost of the 4 distal pore-chambers are separateil from the innermost only by a slit- shaped sinus (fig. 3).
The vibracula which are [)laced on either side of the operculum and are pailly immersed, have an ovale outline, and their frontal area shows a distal.
?^^t^
V\i<. 1. Two zotrcin of Crcp. Poissoni Aiul., var. crinispiiia. X .'>5.
2. A zoccciuin of the same form seen fi'om the basal wall, .-is in lig. 3 pore-chambers alternate with intermediate spaces. X r)5."
3. The distal part of a zocvcinm with ocecinm seen from the basal wall. X 55.
4. An ancestrula of another variety of the same s])ecie.s. X 175.
5. Operculum of Crep. Poissoni, var. erinispina. X 140.
(i. The pro.ximal part of the flagellum of the same form. X 200.
shorter, rounded subopercular area and a proximal, longer and narrower oper- cular area. The flagellum (tig. (>) which is of about half the length of the zo(k- ciuni is very thin, without teeth and in its proximal end provided with a biitlon- .shaped expansion and a short conical cavity. Each vibraculum is in connection with a marginal pore.
268
The ooecia (ligs. 1, .'{), wliich arc only I'orinccl hy a siiigk' zod'ciuni, are free with llie exception of a small |)roxinial ])orlion of the endooa^cium formed by a part of the zod'finm's fronlal wall dislal lo the aperUire. They are strongly arched, not far from being globular and consist of two calcirietl layers of wliich the thick ectooo'cium about the middle is provided with a low, girdle-shaped, proximally convex impression covered by a chilinous jilale of the same form. \\'ilhin the impression is seen an irregular series of mostly elongate pores separated by thick cylindrical j)ilhirs. In the oa'cia-bearing zod-cia Ihc aperture is on each side pro- vided with a small lounded protuberance (lig. li) dislally to the opercular ridge, and the aperture of the od'cium can l)e closed i)y the operculum.
Some colonies of this interesting species have been found incrusling shells at Koh Kram, Siam, al a depth of iiO falh. I)y Dr. Th. Morlensen.
Our Zoological Museum j)ossesses a small colony of another variety from Port Phillip Heads, which has a nearly circular Tata-sha|)ed ancestrula, surrounded by 12 marginal spines (tig. 4). The spines are not only much longer and stronger than those in the variety from Siam but are divided into ca. S inlernodes. The pore-bearing impression of the oa'ciuin is almost circular and within il is seen a number of scattered pores.
hi the form ligured bySavigny the Od'cium seems to be provided with scat- tered pores, separated by a number of parallel longitudinal ridges.
Before being able lo make a thorough examination of the present sj)ecies, I have set forth the supposition in tlie niorpliological jiart that it might belong to the Suborder Anaska and the reason for this supposition was cliiefly the lack of the cross-bar in the vibracula together with a certain likeness to Mecjapora riinjens. Later I have been able to examine some good colonies from Siam, and having seen that the operculum is in connection with a compensation-sac I cannot longer maintain this view, holding however at the same time that this genus has its nearest relatives in the division Malacoxlcga. This appears not only from the lack of the cross-bar, but also from the |)rescnce of marginal spines surrounding a great deal of the calcilied frontal wall. \\'liile a great number of the Ascoplwnt are provided with marginal sjjines surrounding the aiiter of the aperture (»oral spines ), with the exception of Crepklacanihu we find marginal spines i)laced in the circumference of the frontal wall only in the division Malacostega and only in a few ancestruhv for instance in those of C.haperia spinosa^ and Microporclla riliala'- do we find such spines together with a well-developed cry|)tocyst. Though llie sjie- cies of the genus Meejapora are provided with a completely calcified frontal wall
4,'), PI. 5, lig. :i. - 111, p. :VM, IM. l.'>, lig. (i.
269
and with a well-chitinized compound operculiiin they must, I think, he referred to tlie Mdlacoslecja, heing most nearly related to the genus Callopora. The species luialina which Waters' with some doubt refers to the genus Megapora has be- sides 6 larger, distal, marginal spines 1 — 3 very small, seated outside the frontal area about half-way down, and as the second species M. ringens has an aperture of (|uite the same form as that found in C. Poissoni, I think that these two spe- cies are more nearly related to this interesting form than any other species hitherto described.
Having only examined dry colonies I have not been able to find a covering membrane, but as the very low side-walls of the zooecia, when isolated, are sep- arated from the arched frontal wall by an impressed line, I cannot doubt, that lliis line indicates the distinction between a marginal gymnocyst and a frontal cryptocyst, and as the spines arise just proximally to this line they are not, as I originally thought, acropetal but marginal which can also be se6n by a com- parison with the ancestrula.
Family Euthyridae.
The zooecia are provided with a slightly calcified cryptocyst, and in a larger or smaller part of their surface the surrounding covering membrane is kept distended by ridge-like or rod-shaped processes from the cryptocyst, which has a number of superficial rosette-plates. The interzoa^cial \valls have scattered, uniporous rosette-plates. A compound operculum. No spines and no heterozooecia. There may be endozooecial o<i\'in with a projecting, membranous ecloofrcium. Free, branched colonies.
Summary of the genera.
1) Ocrcia occur: the aperture provided with a narrow sinus; (the covering-membrane is everywhere kept distended by narrow ridges
from the cryptocyst) - Urceolipora Mac ("lillivr.
(Calymmophura Husk ).
1) No ooecia, but two dill'erent forms of zooecia; the aperture with- out sinus, hut with an almost straight proximal margin:
2) The IVontal cryptocyst forms a continuous calcareous surface; llic covering-membrane is on the frontal as well as on the basal surface distended by means ol' rod-shaped processes from Ihe crypto- cyst Eiithyris Hincks".
' U.'., p. :ii), lO'i. '-' 27, p. I(i4.
270
2) The frontal cryplocyst is formed hy a iiuml)er of narrow, only partially meeting ribs; the covering membrane is kept distended only on the basal surface of the colony by means of the wedge-shaped, [)ro-
jecting, central portion of the sei)arale zoo'cia Plciivoloichus n. g.
(s|)ccies P. chillirdtiis Harmer').
Urceolipora nana Mac Gillivr. Urceolipora nana Mac Gillivray, Transacl. and Proceed. Royal Soc. of Victoria,
Vol. XIII, 1881 (for 1880), pag. 85, PI. (with- out number, pag. 88), figs. 3 a — 3 c. Calymmophora lucida Busk, Challenger, Zoology, ^'ol. X, Pari I, 18S4, pag. 82,
PI. XXX, fig. 3. (PI. XV, figs. 1 a— 1 f).
The zocecia, which increase greatly in extent from (he narrow proximal to- wards the distal end, have in the greater part of their length an oblong, oval transverse section (tig. 1 c) and when seen from the frontal or basal surface Ibeir form is somewhat vase-like (figs. 1 b, 1 d). The distal end of each zooecium projects a great deal over the i)roximal |)arl of the higher j)laced zocrcium with which it forms an acute angle. The covering membrane is kept distended from the cryplocyst by a number of narrow longitudinal ridges, which spring from the latter, but which arc dilTerenl on the two surfaces of the branch. To begin with, there is on both surfaces of the branch a zigzag longitudinal ridge, which runs in immediate proximity to the suture between the two rows of zocecia (fig. 1 e) and is situated in each zoa^cium on the part which lies between its own distal wall and thai of the lower placed, opposite zoo'cium. This zigzag ridge, which is most strongly developed on Ihe side of the branch turned away from the twin-branch (the abramal side of the branch), is in each of the oa'cia-bearing zocEcia continued into a collar-shaped, vertical part (figs. 1 a, 1 d) situated at the base of the o(r- cium, while in the ordinary zott'cia it is continued into the angle belween two succeeding zocecia of the same longitudinal row. The two ridges from the oppo- site sides of the zooecium are liere joined into a single one, which ends in the distal margin of the aperture some way from the central line on the abramal side of the aperture. On the adramal side of the branch each zooecium is more- over in the greater part or in the whole of its length provided with a strong, somewhat curved longitudinal ridge (fig. 1 a), which is somewhat different in the zocEcia arising from oa>cia-bearing zoo-cia and in those springing from non-o(ccia-
' 19, p. -Jdf).
271
hearing zociecia. In the former it springs from the lateral surface of the zoa'cinm close to tlie zigzag ridge and at a fairly great distance from the distal wall, and in the latter it starts from the approximate centre of the proximal part of the frontal surface. In both cases it ends in the above-mentioned, collar-shaped i)art at the base of the oa^cium. To keep the covering-membrane extended there is further a very small, flat, most often trapeziform process situated on each side of the aperture. This process Busk wrongly takes to be an avicularium (hgs. 1 a, 1 f).
Along the frontal margin of the abramal zigzag ridge we find on each zooe- cium a longitudinal row of 5 — 7 small, widely separated, uni[)orous rosette-plates, and similar rosefle-plates appear on both sides of the adramal arch-shaped ridges. Along the frontal margin of the ridge there are 6 — 8, while those on the other side of the ridge are more varying in number (^ — 7), and may sometimes be rather irregularly scattered. Finally each of the two frontal rows of rosette-plates is continued into a row or grou[) of 4 — 8 plates situated on each side of the aperture.
The obliquely a.scending distal wall has a basal trilobed margin and is pro- vided with numerous, uniporous rosette-plates, which are scattered over its entire surface, and such plates appear also in a longitudinal belt or row, which passes Ihrough the whole centre of the basal surface (fig. 1 d).
The obliquely truncated aperture, which forms an obtuse angle with the fron- tal surface, has a semi-circular anter, while its poster is provided with a well- developed rounded sinus. The slightly chitinizcd operculum, which is of a corresponding forLu, has a somewhat curved, transverse row of round, bright spots.
The ooecia are of a most |)eculiar structure, being endozoa^cial and al the same time having their endoocrcium situated frontallj' to the cry[)tocj'st of the zod'cium, whicJi is much excavated to receive its strongly arched basal surface. There is a transparent ectooa'cium, formed by the covering membrane, and a calcilied, radiately striated endoooecium, which is somewhat nan-owed at the base in the shape of a neck, and the form of which is that of a Phrygian cap rounded at the end. A large |iart of the frontal surface of the endoocrcium is provided with numerous, round, attenuated spots. The distal wall belonging to the ocecium has rosette-plates not only in its basal trilobed pari but also in the narrow part bounding the on'cium on either side. Finally, il may also be i-enuirked llial llie oo'cium can be closed by the operculum of the zoo'cium.
The colonies arc richly branched, bifurcated tufts with compressed branches
272
each hearing two rows of zo<»'i'ia, with Ihoir hasal siirlaccs towards each other.
Stat. 1G3 A, Challenger (British Musenm).
Euthyris obtecta Hi neks. Annals Nat. Hist., Ser. fi, Vol. X, IS.S'i, pag. !)6, IM. 1(1, iigs. ;!2— ;57. Harnier, Qnarl. Jonrn. Micr. Science, n. s. Vol. 4(5, \W,\, i)ag. 277, PI. 1"),
tigs. 13—14. (PI. \V, fig. 2a-2l).
The zooecia are slighlly calcilied, arched, I'roni a narrow proximal end ex- panding dislally, with a distal end ohliquely a.scending towards the frontal cover- ing menihrane. When seen from the frontal surface they seem to he cylindrically oval, while from the hasal surface of the colony they are of a lyre-shaped out- line. The strongly projecting covering memhrane is directly connected with the separate zowcia only in the periphery of the aperture of the latter, and he- sides only in contact with them through rod-shaped or ridge-like processes from their surface. The aperture is provided with two well-developed, rounded hinge-teeth. Its anter is semi-circular and rather high and its j)oster ahont half as high, hi the latter we may more or less dislinclly distinguish hctween two proximall}' converging lateral portions and a central j)ortion. The accessory part of the operculum has a wcll-chilini/.cd margin, on either side of which Iherc is a small, tubercle-shaped process corresponding to a small, rounded indentation on the proximal side of each hinge-tooth, hi the somewhat neck-shaped i)art of the zofficiuni proximally to the aperture we find a circle of 8 — 10 superficial, uniporous rosette-plates and a larger number (15—2(1) are scattered over the entire basal surface. There are further numerous, uniporous rosette-plates in the basal pari of the distal wall, and a zig/ag row of about S such plales in the dis- tal half of each lateral wall.
The connection between Ihe projecting covering nuMubrane and llie cryptocyst is brought about, as far as the frontal and basal surfaces are concerned, by means of a numlier of thin, compressed, almost filiform calcareous prolongations, which join the covering membrane with a T-shaped terminal part. The.se struc- tures appear on the frontal surface only on the two outer series of marginal zoa-cia on either side, and on the series next to the outermosi one they only appear in a number of 2 — 3 a little proximally to the aperture and near the outer margin. In the distal half of the marginal zoeecia they are present in a larger number of about 4 — 7. On the i)asal surface they are found in all zod'cia in a number of 4 — 12. On the middle row of zoiecia we find the distal half of each zod-cinm
278
])rovided with 4 such spines, which I'onn a pretty regular tpiadrangle, heing situated 2 hy 2 a little inside each lateral margin. There is a larger number on the 3 lateral rows on either side. The inneruiosl of them has generally one in the outer half besides the 4. The next row has usually one more, but in the outermost row the numlier is increased to 10 — 12, of which 5 — 6 are situated along the outer margin, 2 — 3 along the outer half of the distal luargin, and the rest scattered over the distal half. In the older parts of the colony the projecting covering membrane of the marginal zoa'cia is connected with the cryptocyst of Ihe lateral walls by 3 — 5 compressed calcareous plates, which sjiring from each zou'cium and are separated by rounded openings. Each of these plates again joins the covering membrane with a thick, (juadrangular expansion, which is situated vertically on the compressed part and is slightly bent from side to side in the shape of a roof. This quadrangular expansion has a densely tuberculated outer surface.
The colony is free, branched, with narrow branches, the zocrcia of which are only completely symmetrical in the central portion of the branch and be- come more and more asymmetrical towards the lateral margins.
Of this form I have examined only a small dry fragment fioin North Au- stralia, which was kindly placed al my disposal by the late Mr. C. N. Peal. It dilTers in several respects, for one thing in possessing only a single form of operculum, from the form described by Hincks and Harmer, and perhaps it may be regarded as a distinct species.
Family Savignyellidae n. f.
The narrow, elongated, rather slightly calcified zmvcia have a frontal surface, provided with scattered pores, which is separated from the basal surface by a more or less sharp boundary line. The distal wall has a number of uni[)()rous or multiporous rosette-plates in its periphery. Spines may appear round the ajjerture, proximally to which there may be a freely projecting avicularium. We may (ind free ooecia, two-layered from the proximal part, the ecloooecium of which has a membranous frontal side. The colonies are richly branched, jointed, and each inlernode consists of a single zooecium.
18
274
Genera:
The aperture surrounded by spines, with a concave poster and with no sinus; an avicularium proxiniallj' to tlie aperture; distal wall
willi uniporous rosette-plates; ooccia jiresent Scwiynijella n. g.
Catenaria d'Orbigny. (S. Lafonti Audouin^) The projecting aperture not surrounded by spines, Init with a rounded sinus; distal wall with niultiporous rosette-plates; avicularium
and oa>ciutn wanting H(tlysisis Norman -.
(//. diapbana Busk^.)
Time has not allowed of my entering into a close examination of the two species, which I think show sufficiently great conformity to belong to the new family that I have been obliged to found for them. It is possible that C(iteiuiri(t<^ uttemiata Busk^ may also be entered in this family. With regard to the cpiestion of their descent, they seem to me lo show relationship particularly to liicellariidae, and of characters that favour this opinion I may mention the slight calcification, the long slender form of the zomcia, the form of colony and the structure of the oo'cia. Also the freely projecting avicularium in S. Lafonti may be taken as evi- dence of such a relationship. While I have found a covering membrane on the frontal surface in C. diuplmna, I have not succeeded in finding one in S. Lafonti, in which however according to the examination made by Calvet it must be supposed to be present. — The two just-mentioned sj)ccies have by Busk* and later authors been called Alijsidiuni Lafonti And. and Catenaria diaphana Busk. But it has been necessary to make two new generic names, as tlie name Ali/si- dium must be kept for A. j)arasiticnm Busk, and Catenaria Contei And. is the ty|)e of a genus belonging to the family Catenariidae (see pug. 2i;{, note).
Family Hippothoidae. Diazeuxidae JuUien.
The zoo'cia, which have no covering membrane, are generally thin-walled, glistening, more or less distinctly longitudinally or transversely striated, and the calcification, which constantly increases simultaneously with the growth, lakes place in transverse belts, of which a greater or smaller number often terminate in thin protruding margins, which .surround the frontal surface like a belt.
' ns, pi. l.t, ngs. 2,.— 2,7. -' 84 a, p. 29r>. ' 8, p. 14. ' 2, pp. l.'l — J4.
275
Ordinary spines are usually wanting, whereas short wide acropelal spines not seldom appear, partly on each side of the aperture, partly singly on its proxi- mal side. Aviciilaria are very seldom present, but we frecjuently Mnd very small, sometimes rudimentary zoa-cia, which are however provided with an ajjcrture. The zon'cia in the whole of their periphery have small uniporous or few-pored pore-chambers, and the pore-chambers of one zoo?cium not rarely join short prolongations of the other, by which means two neighbouring zorecia be- come separated by a row of small openings. The owcia are sometimes situated on zooecia of ordinary structure, sometimes on gonozocecia of a peculiar form. They are covered either by kenozoa>cia, dwarf zoa^cia or by avicularia. The colonies are incrusting.
The zooecia have no covering-membrane, and when Calvel' talks of a cryp- tocyst in Chorizopora Brongiarti, the reason may be that he confuses it with the compensation-sac, the opening of which in this form needs however a closer ex- amination. The fact is that Chorizopora possesses a simple operculum, but con- trary to all the other genera of the section Ascophora in which this is the case (Microporella, Iiwersiiila, Adeona, Haplopoina, Tiibucellaria, Caliuellia and Onvho- pora), it wants an ascopore, and as the proximal margin of the operculum seems to go close up to the corresponding proximal margin of the aperture, there seems to be no room for any opening ])elween them. Excepting that Jullien^ has found marginal spines in some ancestrulae of HippoUioa-co\onie>i, and lliat Kirkpatrick'' has described a Chorizopora-torm with two pair of spines in the distal end of the zofrcium, ordinary spines are otherwise wanting in this family, whereas in all the four genera, though not in all species and varieties, the hollow expansions occur which I have mentioned in the diagnosis of the family. Hi neks' calls the small cliambers, wliich in Trijpostegd neimsta are found partly scattered among the zott'cia, partly surrounding the oa>cia, avicularia; but as their aper- ture wants the transverse bar found in the avicularia in Chorizopora between the opercular and the subopercular area, I prefer to call them dwarfed or rudiment- ary zooecia, especially as except in the genus Haplopoma we lind wilhin the three other genera of the family individuals of different size, form or structure scat- tered among the ordinary zorrcia. Thus, in Chorizopora we may find large num- bers of very small chambers mixed with some avicularia, and the round aperture of these chambers seems to be covered only by a membrane, while the corre- sponding chambers in Trypostega Deiuisht have a small chitinized operculum, which is different from that of the ordinary zotrcia, but which does not how-
' 9, p. KiG. - 45, p. 30. ^ 4<), p. 01.'). ' 2'i, p. •J/d — 1277.
. 18*
270
ever cover the whole of the aperture. Finally we find in a niiiiiher of species of the genus Hipjjotlioct partly unusually small or unusually narrow zod-cia with aperture and operculum of the ordinary structure, partly dwarf zoa-cia with a dilTerent form of operculum, which does not cover the whole of llic ajx-rture, and last of all kcnozocrcia. hi conclusion I luay just mention that while the separate chamhers of the colony are connected by small pore-chamheis, the septum between the gonozoa'cium and the kenozocecium covering the od'cium is provided with a row (in H. luidliiid with 4 — 6) of uniporous rosette-plates.
Synopsis of the genera.
1) The aperture with a simple operculum:
2) A median ascopore proximally to the aperture; oa'cia covered
by kenozocecia; zocEcia with scattered pores Haplopoma n. g.
2) No median ascopore; ooecia covered by avicularia: the zocrcia
with at most a row of pores on each side Chorizojioni llincks.
1) The aperture with a compound operculum, which is generally provided with a sinus:
;{) Oa>cia covered by kenozoa^cia; zoeecia without pores. . . flippolhon I^amour.
3) Oa^cia covered by dwarf zocecia with ojjcrcula; zoacia with scattered pores Triiposte</a n. g.
Hippothoa I^amour. Hippothoa Hincks, Schizoj)()rella llincks, Diazeuxia Jull.
The zoa'cia have no pores, and the aperture is provided with well-developed hinge-teeth and has .generally a sinus, more seldom a convex proximal margin. A compound operculum with a broader or narrower accessory [)art. The gono- zoo'cia bearing the 0(ecia have an operculum with a very small accessory part, and the o(rcia are surrounded by kenozoa-cia without aperture '.
Of the numerous species belonging to this genus only a smaller numhui- have been described. They differ in form of aperture and hinge teeth, in the absence or presence of acropetal spines, in position and structure of the gonozoo'cia, in structure of the kenozocecia, in mutual connection of the zocecia, etc. The difler- ence in position and structure of the gonozocrcia a])pears from the fact, that these individuals in some species (e. g. in H. corniilit) are situated on a level with the other zooecia and are of similar size and form, while in other species (e. g. H. hijalina and //. (iimiihiris) they are situated on the frontal wall of the
PI. XVIII, fi". 9 a.
277
ordinary zoopcia, from which thev dilTer in form and size. In the majority of species the kenozoa>cia are provided with scattered pores, while in a smaller number of species and as it seems in all the species that may be referred to Hippoihoa Hincks, they are entirely without jiores but possess a median, projec- tiufi; portion. In most species as in Chorizopord Broni/niarli the zoci'cia are separ- ated by a number of small openings, which however are wanting in a series of species, e. g. in //. aniuilaris and H. corniita.
H. annularis Moll. Lepralia annularis Busk, Catalogue of Marine Folyzoa, Cheilostomata, pag. 85,
PI. XCV, figs. 1, 2. (fls. XXI, figs. 7a-7f).
The zooecia are elongated, triangular, trapeziform or rectangular, from the proximal end strongly ascending and leiininaling in a j)orlion, which is strongly arched from side to side as well as distally proximally and almost hunched or expanded. The maximum height of this portion is attained approximately in the distal third of the body. On either side of the ajjerture and bent a iiltle towards it there is a short, stout, wide expansion or acropetal spine, which is rounded at the end and looks like a horn. The anter of the oblong aperture (fig. 7 1)) is provided with two lateral margins, which only converge slightly distally and meet in a curve. Its poster has in the centre a very small, transversely oval sinus bounded on each side by a trapeziform process, which is again separated from a small hinge-tooth by a very small indentation. The well-chitinized oper- culum (fig. 7 e), which has an accessory part corresponding to the sinus, is within each lateral margin provided with a long, almost cucumber-shaped groove, which is surrounded by a chitinized margin and probably serves as attachment for the o|)ercular muscles. The distal wall (lig. 7 d) is angularly bent from side to side, and besides the two large distal pore-chambers, through which each zoo'cium communicates with one or t\^o others, we find in each lateral wall either ',i — 4 small pore-chambers or 3 openings, which correspond to as many [)ore-chambers in the neighbouring zoo^cium. 1 — 4 small, superficial pore-chambers (lig. 7 c) are found on most zoa-cia, most often on one side, but sometimes also on the other. They' appear near the suture towards the neigbouring zoa-cium and decrease in size distally. Of these pore-chambers the proximal one is situated near the dis- tal wall.
The ooecia, which occur in shorter or longer, continuous, curved transverse rows (lig. 1 a), are borne by short, broad, conically cup-shaped gonozoa^cia, which are situated on the frontal surface of the zooecia and communicate with the latter
278
tlirough Ihe jiist-mentioncd superficial poie-cliambers. They arc covered by strongly arched, peiitagonally rounded kenozocrcia, which are twice the length of the gonozorecia, terminate at the lop in a \unni and meet in i)arallel sutural lines. Besides a circle of marginal jiores, which are j)arlially covered by neigh- bouring /oa-cia, there are slill a few scattered pores in their distal part. The well- chitinized operculum (fig. 7 f), which has the form of a segment of a circle, has in its proximal margin two small, rounded sinuses corresponding to two rounded pro- jections on the proximal margin of the aperture. A little inside each lateral margin we find a rounded process for muscular attachment.
The colonies occur as circular or fan-shaped discs on alg:v, and, contrary' to all the other species of this genus that I liave examined, tlie zotrcia are arranged in continuous, arch-shaped transverse rows.
Two colonies of this species, without statement of locality, are found in the lierbaiium of alga- in the Botanical Museum.
H. cornuta Busli', var. holostoma n. (PI. XXI, figs. 8a-8g).
The zooecia are elongated, generally pear-shaped, evenly ascending towards the distal end and provided proximally to the aperture with a large strongly pro- jecting, hollow expansion (fig. <S g) bent more or less distinctly in the shape of a knee, in which we may distinguish Ix'twcen a broader proximal j)art and a narrower, at the end broadlj' rounded distal part. The aperture is wholly or partly hidden by the latter part, when the colony is regarded from the frontal surface. On the boundary between the two above parts the expansion mentioned has an internal, transverse septum, which is perforated by a transversely oval pore. As in the foregoing species we find on either side of the aperture a horn- like expansion rounded at the end, which is however longer and more slender, less bent towards the aj)erture, but directed more distally. A smaller expansion is not infrequently found in the middle of the frontal surface, sometimes in the central line, sometimes towards one lateral margin. The ba.sal surface of the zoa-cium, which has a small uncalcified portion centrally, is on its inner surface, especially in its proximal hall", provided with numerous, narrow, scattered, papilla- shaped processes, which have the free em\ turned towards the distal end. Con- trary to the other species examined by me the aperture (fig. <S c) has no sinus, and the bicusped binge-teeth separate an almost semi-elliptic anter from a poster, the height of which is only about one-third of the former and its slightly
' 2, p. 84.
279
converging lateral margins meet in an almost straight or slightly curved margin. The well-chitinized operculum has on the other hand a broadly quad- rangular, accessorial (tig. <S d) and within each lateral margin a short, slightly curved muscular ridge. As in the j)receding species we find two large distal pore- chambers bounded by the angularly beni distal wall, while each lateral wall has 3 — i communications with the neighbouring zou'cia.
The ooecia (figs. 8 b, 8 c) occur in small numbers scattered among the zone- cia, and the gonozocecia are provided with a large, broad, somewhat flat, lip- shaped, obli([uely ascending expansion which is situated proximally to the aper- ture. The latter is wholly or partly hidden by the expansion and its proximal margin is slightly angularly bent. The operculum (fig. 8 f) has a small, com- j)resscd process on either side. The strongly arched kenozooecia have a number of scattered pores, which are however wanting in the steeply ascending portion distally to the aperture and the projecting central portion of the frontal surface is generally developed as an expansion, more or less sharj)ly delimited.
As the form just-described dilfers in the want of a sinus in the poster of the aperture from Lepralia hiidliiui, var. coniiita described and figured ))y Busk ' 1 originally felt inclined to consider them specifically dilTerenl in s|)ile of llie corresponding development of expansions. But as I have had a later op- portunity of examining an aj)parently closelj' related form from Victoria, the aperture of which is provided with a well-developed sinus (fig. 9 b), I must supi)ose all three forms to be varieties of one species, Hippothoa corniila Busk, which is very variable, not least in the form of aperture. This variety may be termed uporosa. The three expansions are of a similar form and structure as in var. holostoiua, and the median expansion especially is provided (lig. 0 a) with a similar septum perforated by a pore. The gonozoa>cium (fig. 9 c) has a similar lii)-shaped expansion, but its aperture, like the zoa^cial aperture, is pro- vided with a narrow, deep sinus, lo which a process on the oi)erculuni (fig. 9 e) corresponds. The kenozooecium, which to judge from the figure only possesses a circle of marginal pores in Busk's form, is here at the outside furnished with a few median pores and is even more strongly arched than in var. luilostoina, its surface being very hunched. A small colony from Victoria has Ijcen found on Plerocladia Incida in the herbarium of algtc in the Botanical Museum.
2, p. 84, PI. \C\\ figs. 3—5.
•im
Haplopoma n. g.
The zod'cia with scattered pores, a simple operculum and a median ascopore as an orilice lor the compensation-sac. The oa'cia covered by kenozoa'cia with scattered pores. No avicularia.
H. impressum Audouin. Microporella impressa Hincks, Hrilish Marine Polyzoa, pag. 214,
PI. XXVI, (igs. y— 11, PI. XXIX, iigs. 10, 11. (PI. XXII, ng. 9a-<)b, lOa-lOe, I'l. XVIII, lij^. ll a).
While Hincks and all later systematic authors have referred this species to the genus Microporella, wilh the species of which it agrees in the possession of a median ascopore, a simple operculum and pore-chambers, Barrois' in his greal woik on the larvae has rightly recognised its relationship to Hippothoa hijitliim and called attention especially to the great similarity of their larva', which be- long to rather a peculiar type. He is however wrong in referring both these species to the same genus {Mollia).
The supposition, expressed on several former occasions, that the median asco- pore has arisen by a conslriclion from an original sinus is also conlirmed in Ihis species, and Waters^ has already called attention to the fact, that the primary zoo'ciuni in //. iinprcssiim (PI. XXII, figs, i) a — 9h) as well as in H. biiniicrnnatitm, Moll (PI. XXII, iigs. 10 a — 10 c) is provided wilh a sinus, which is however both narrower and deeper in the latter than in the former. The primary zoa^ciuni in the laller species is moreover distinguished not only by possessing a curve of 9 l)()res, but also by having an oi)erculum (fig. 10 e) similar to that found in the genus Arthropoina, the accessory part of the operculum, corresponding to the sinus, being separated from the principal part by a less strongly chitinized por- tion. This dilferencc in the primary zocrcia also speaks in favour of the opinion maintained by Waters, that H. biimnronatiim, which was formerly considered but a variety of H. impressum, is a dislinci species.
Genus Trypostega n. g. The zon-cia with scattered jxjres and a compound opercidum. The oo'cia covered by dwarf zoa>cia with scattered pores. No avicularia.
' 1, p. 171, I>l. '.), fii^s. 1 — 3, IM. Hi, lit;. 2. - ll.V p U.
281
T. venusta Norman. Schizoporella venusia Hincks (incl. syn.), British Marine Polyzoa, pag. 27B,
PI. XXX, figs. 6, 7. Lepralia inornataGai)!) el Horn, Sniilt, Kgl, SvenskaVetensk. Akad. Handlingar,
Bd. 11, No. 4, 1873, pag. 61, PI. XI, figs. 215— 216. (PI. XIX, ligs. la-Id, PI. XXII, figs. 13a-13d).
The zooecia are generally rounded rhoniliic, provided with numerous scallered pores, strongly arched and ascending towards the portion immediately on the proxi- mal side of the aperture, which terminates in a strong, hollow, often irregularly luherculated, conical, umhonate expansion (fig. 13 a). The ohlong aperture nearly on Ihe boundary of the proximal third has a pair of strong hinge-teeth, each of which is situated within a triangular, inwards projecting part of the lateral margin. Its antcr has two proximally converging, lateral margins, and its triangular poster is hounded by a somewhat prolriuling, almost rectangularly curved margin. The well-chitinized operculum (PI. XXII, fig. 13 e) is in its principal part provided with small, scattered tubercles and a litlle inside the margin with a well-devel- oped opercular arch. The numerous small dwarf zoa^cia, which are scattered among the zoa-cia (PI. XIX, fig. 1 a, PI. XXII, fig. 13 d) are on the examined colony of a rounded quadrangular form. The very small, quadrangularly oval aperture is bounded proximally by a somewhat protruding margin and not wholly covered by the well-chitinized, finely dotted operculum (PI. XXII, fig. 13 d), which has an almost straight or slightly concave proximal margin. The distal half of eacii zofrcium has a continuous curve of 5 — 6 large pore-chambers (PI. XIX, fig. 1 b) and such are also found in the dwarf zoa^cia.
The ooeria (PI. XIX, fig. lb, PI. XXII, fig. 13a) are surrounded by dwarf zod'cia, which only dilTer from those appearing among the zoo'cia by being larger and of a rounded j)entagonal form.
Of this species I have been able to examine a small colony from Guernsey, which was sent me by the Rev. Norman, and another colony from Port Phillip (Miss Jelly), which in all essentials agrees with the British form, the only dill'er- ence being its want of an expansion proximally to the aperture.
I.vprulia claviciilata Hincks ' must certainly also be referred to this genus, imt as the offcia here seem to be enclosed by kenozooecia without aperture, the dia- gnosis of the genus would have to undergo a small alteration to be made appli- cable also to this form.
34, p. .'.tl,
282
Family Adeonidae Busk'.
The zixvcia, llie entire frontal suirace of which is provided with a Frequently slrongly eolourod covering inemhrane, are always without spines, exlreniely Ihick- walled and slrongly calcified. There are generally pores, and (he partition walls are provided with numerous (in the distal half of the zou'cium usually 14 — 16), small, uni])()rous roselte-plates disposed in a single row, which on account of the thickness of the walls appear at the end of long canals, and the pores ap])ear in a similar way. Owing to the continued deposition of calcareous matter a second- ary, .sometimes even a tertiary, aperture is always present. This is more or less dilTerent from the primary one, which has most often a sinus or a concave proxi- mal margin. The operculum is generally well marked oil" from the covering mem- brane. Aviciildiiit are hardly wanting in any species and occur in most species both as dependent and independent. They are always without a calcified trans- verse bar between the opercular and the subopercular area, and at lis base the mandible has on either side a strongly protruding muscular process, (hrcia are wanting, but gonozoircia appear in most species. The latter are somewhat larger than the ordinary zoa^cia, from which they further dilTer by possessing a broader aperture and l)y being generally better provided with pores. The colonies are usually free, two-layered, sometimes laminate, sometimes branched, more rarely incrusting.
This extremely natural and sharply delimited family was founded by Husk in his report on the Unjozoa of the (Challenger Expedition. Hut just as the author did not succeed in comprehending this family in all its extent, overlooking as he did, that his ^MiicroneUu' puriformis, set up in the same work, also belongs to it, so also is his diagnosis of the family very incomplete, as of real, general, positive characters he mentions only one, viz. the above-mentioned peculiarity in the avicularian mandible, which however according to Waters'^ may also be found in members of other families. On the other hand, Waters^ has pointed out that the median pore which according to Busk is found in all nnMnhers of tliis family can not be regarded as a family character, as this pore in some spe- cies leads into the zoaH'ial cavity itself (Adeoiut, Adconellopsis), while in others it leads into the space between the primary and the secondary aperture {AdconeUa).
This incomplete diagnosis of the family may be one of the reasons for tlie fact, that in .spite of its naturalness this family has not been adopted by a single
• 8, p. 177. - lUOa, p. 777. " UKI, p. 283.
283
author, at Icasl not for any length of time', or in the extent in which it was set up by Husk. With regard to the dilTerent opinions concerning this question, I may refer to the discussion of it l)y Gregory^ under the title of: "The system- atic position of the Adeonellidae « , and I may here confine myself to the remark, that the sjjccies of Adeona and Adcoiiellopsis have hy all authors been leferrcd to the family Micruporellidae, the two genera being sometimes retained, sometimes merged in Microporella.
Synopsis of the genera.
1) The zocrcia provideil in the central line with a single or a group of connected ascopores:
2) With one or two simple ascopores Adcoiiit (Lamour.).
2) With one or several stellate ascopores Adeonellopsis (Mac Gill.) Lev.
1) The zooccia without such median ascopores:
U) The proximal part of the secondary aperture, which appears sooner or later, is transformed by a coalescence of two calcareous pro- cesses into a pore, which leads into the space between the primary and the secondary aperture Adeonelhi (Husk) Waters.
'6) Tlie proximal part of the secondary aperture is not transformed into a pore Bracebridgia Mac Gill.
In the above synopsis no regard has been paid to the form of the primary aperture or the structure of the operculum, for the reason, that the form of the primary aperture, to judge from the relatively small number of species examined in this respect, is subject to rather great variation within the separate genera.
Adeona violacea Johnston.
Microporella violacea Hincks, Hritish Marine Polyzoa, pag. 216, PI. XXX, ligs. 1—4.
Adeonella insidiosa Jullien, Resultats des Campagnes scientifiques du Prince de
Monaco, fascicule XXIII, Hryozoaires, 1903, pag. 54, PI. VI, fig. 4.
(PI. XIV, ligs. 1 a-1 g).
The zooecia, the finely tuberculated surface of which is covered by a black,
strongly iridescent membrane, are elongated, hexagonal and provided with rather
numerous pores, which are most closely situated in the marginal portion. The
' Mac G illivi-ay (69, p. 133) originally adopted Husk's family in all its extent, while in the follow- ing year (75, p. 20!)— 13) he referred Adeona and Adeonellopsis to the family Microporellidae and Adeonella to Escharidac. In his last work (76, p. DO) he refers Adeonella to Schizoporellidae. * 16 a, p. 241.
284
ascopore is silunled proximally lo Ihc cenlre of the Ixxly in a more or less devel- o])C{i depression. The jiriniary a])erliire, which has no dislincl hinge-teelh, is ahnosl semi-eircular and honnded l)y a proximal, nearly slraij<hl or slighlly eon- vex margin. The operculnni (fig. 1 1) is not sejjaraled I'rom Ihe covering mem- brane, and with the exception of a narrow marginal i)ortion it is meml)ranoiis; only in old zoo-cia the part corresi)onding to the secondary aperUire may be slightly chitinized. The secondary apertnre is of a somewhat variable, ronndish form, most often somewhat broader than high, and with less concave, sometimes almost straight proximal margin. Each zoa'cinm has in its distal half 14 — 10 uniporous rosette-plates and in its proximal half as many o[)enings. hi most corners between tlie zoa>cia we find very small rounded cavities covered by a membrane, which seem lo be kenozocecia.
Avicularia. A long, narrow, pointed avicularium is fonnd in most zo(i>cia a little distally to the median pore. It is directed towards (he aperture and may reach some way past the proximal margin of the latter, histead of the avicularium we find in a smaller number of zoa'cia (fig. 1 b) an annular ()i)ening, which leads into an elongated, sometimes .somewhat swollen cavity.
The gonozooecia, which are scattered singly or in groujis among the zocrcia, are considerably larger than the latter and of an angularly oval form, ^hireover they differ from the ordinary zon-cia by having a greater number of pores, a broader, transversely oval aperture and two coalesced ascopores. The aviculariimi is never developed, but is replaced by a cavity similar to Ihal found in a smaller numlier of zoa'cia.
Of this species I have examined a numl)er of colonics from Syracuse (rockj' and shelly bottom, 12— 25 fm., Dr. H. J. Hansen), which occur partly incrusting on calcareous alga;, partly in free, one-layered expansions. They agree with a small colony from Guernsey (Norman) also in the possession of a single ascojiore and of the small round kenozoo'cia, and as the latter thus contrary lo the de- scriptions of Hincks and. lul lien, are not necessarily dcpcndenl on the |)resence of a double pore, I find no reason for regarding Hincks's var. a as an inde- pendent species, as Jul lien does.
Adeonella serrata n. sp. (I'l. XIV, lijis. 2a-2j.). The zooecia, the finely tuberculated surface of which is covered by a light- brown nu'mbrane, are generally rhomboidally vase-shaped, strongly arched and provided with scattered i)orcs. Tlie primary aperluie, which is provided vvilli well-developed hinge-teeth, has a large, well-defiiu'd, broadly rounded sinus imd
285
a separable, chitinized operculum, while the somewhat projecting secondary apei'- ture is irregularly circular, sometimes short, transversely oval. Each zoa»cium has about 12 rosetle-plates in its distal hall'.
The gonozooecia. whicii are considerably larger than the ordinary zoa-cia, are provided with numerous pores, and the primary as well as the secondary aperture is much broader than in the zoa-cia. The proximal margin of the sec- ondary ajjcrture is sometimes almost straight, sometimes rather j)rojecting cen- trally, and it is separated from the large, peristomial pore by a high bridge. They appear everywhere along the margin of the colony on both surfaces and form a belt of up to three longitudinal rows.
The avicularia occur both as dependent and as independent, of which the latler may be larger than the gonozooecia and especially attain a more consider- able length. They have a well-developed cryptocyst and a long mandible, the two sides of which are sometimes almost parallel and meet in a curve at the end. They api)ear in larger or smaller numbers in the marginal j)ortion of the colony, scattered sometimes singly, sometimes in smaller groups. Within each bifurcation 1 — 5 are always seen, of which the inner one or inner ones always go further inwards on the branch than in the other parts of the colony. The dependent avicularia which are found on the separate zooecia in a number of 2 — 3, very seldom 4, are of a rather long, triangular form, and they have the point turned in every possible direction. If 3 are present the two are most often situated on either side of the peristomial pore at the same or nearly the same level, and if there are only 2, the one wanting is most often one of the distals. On the gonozo<jecia the two distal ones are generally situated on either side of the peristomial pore anil have the points turned obliquely inwards and dis- lally.
The colonies are two-laj'ered, richly branched, bifurcated, with compressed branches, which may attain a breadth of about 4'""' As the daughter-branches behjnging to the same mother-branch never lie at the same level, but are bent more or less strongly in dilVerent dirciiions, the neighbouring branches coalesce in numerous irregular ways. The zod'cia on the separate branches are disposed in oblique, somewhat curved rows and each row terminates in two or sometimes three gonozocL'cia. hi the margin of the colony we find a more or less sliaiply broken row of single individuals, partly kenozooecia of very dilTerent size, whicli may bear a small avicularium, partly independent avicularia, the terminal part of which is strongly projecting, thus giving the branches an irregular, serrated appearance.
286
This species is present in great numbers from the Formosa Cliannel, Lat. 23" 20' N., Long. US" 30' E., 17 fath. (Andrea).
Adeonella Jellyae n. sp.
(IMs. XIY, lij^s. la-ig, Ih, 4 i).
The zooecia, tlie finely tuberculated surface of which is covered by a brown- ish violet membrane, are rhomboidally hexagonal or vase-shaped and provided with scattered pores, which arc most numerous in Ihc marginal portion. The l)rimary aperture, which only in the very youngest zoa-cia lies immediately on the surface of the colony, has an almost quadrangularly rounded anter, the two almost parallel lateral margins of which meet in a curve. The more or less con- vex poster is provided with a sharply bounded, quadrangularly rounded sinus, the breadth of which is about one-third of the aperture and is almost as long as it is broad. There are well-developed hinge-teeth and a well-chilinized operculum. The secondary aperture, the development of which passes through many stages, attains the structure peculiar to the genus only in very old zooecia. II is thus at a certain point of time provided with a large rounded sinus, the proximal part of which finally becomes a pore. The form of the real secondary aperture varies between round and semi-elliptical, often with an almost straight proximal margin, hi the distal half of the zooecium there are 14—16 uniporous rosette-plates.
The gonozooecia are scattered in smaller numbers among the ordinarj' zooe- cia. They are only a little larger than the latter and have an ajjcrture of a some- what different form. Us anter is almost semi-elliptical, and its slightly convex poster is provided with a rounded sinus, which is at its starling point about half as broad as the aperture.
The avicularia have a rather long, triangular mandible and appear both as indei)cndenl and as dependent. The former, which may attain a size similar to that of the zooecia and which have a rhomboidally vase-like form, are scattered over the surface of the colony, singly or in groups of up to 4. The dependent avicularia, which are not only found on the zocrcia and the gonozoa'cia, but in rare cases also on the independent avicularia in a number of 1 — 2, are subject to some variation both with regard to number and position. There are generally two ])roximally to the aperture, which have the points turned obliquely jiroxi- mally and towards the centre, but one of them may be directed distally in a smaller number of zooecia. Very often we find proximally to these two still a third, the position of which may be very variable.
The colonies appear as bilaminate, foliaceous, folded and lobed expansions,
287
which form labyrinthic and cellular masses by concrescense of the single lobes and laminate folds.
Port Elizabeth, South Africa (Miss Jelly).
This species is certainly closely related lo ^Schizoporella-^ biimin'dii Hincks', which undoubtedly must also be referred to the genus Adeonelhi.
Adeonella pygmaea n. sp. (PI. XIV, li-s. Ij, 4 k).
The zooecia very small, finely tuberculated, as a rule rounded hexagonally or vase-shaped, with scattered pores. The primary aperture, which, in contrast to what is found in the foregoing species, is only seen on quite a few zoojcia at the end of the branches, has an approximately semicircular anter and its poster has a broad, rounded sinus, which at its beginning is as much as two-thirds of the whole breadth of the aperture. The operculum is wcll-chitinized. The secondary aperture is semicircular in its final form, with a sometimes almost straight, some- times somewhat convex proximal margin, and the small median ascopore, which is placed in a depression, lies just as far from the aperture as the height of the latter.
Gonozooecia were not observed.
The avicularia seem only to occur independently and each zocecium is only j)rovided with a single, fairly elongated, pointed avicularium situated on the outer (directed towards the corresponding lateral margin of the branch) side of the zooecium, with as a rule its point directed obliquely inwards and towards the aperture.
The colonies are two-layered, free, branched, with narrow, compressed branches, but the colonies examined, which are situated in large quantity and in very differ- ent stages of development on a large colony of Ad. Jellyae, arc undoiditedly very young, as the largest of them only has a length of g"""- and consists only of four branches. Whilst the younger colonies are quite light in colour, the older have a somewhat similar colour to that of the species on which they grow. Pos- sibly they may be j'oung colonies of Ad. Jellyae.
Adeonellopsis foliacea Mac Gill. Trans, and Proc. R. Soc. Victoria, Vol. XXII, 188(i (for 1885), p. 134, PI. II, fig. 1.
(VI. XIV, rif>s. r)a-.5(l).
The zooecia finely tuberculated, covered by a grayish-black membrane, as a rule rhombic, provided with scattered pores, which occur chielly on the marginal
' ai, p. 2iio.
288
region and usnally in very small number on the median region The primary aperlurc, whicli is provided in each corner with a strong, rounded liinge-tooth (fig. 5 b), is more than twice i.s broad as it is high, with an angularly arch- shaped anter and a faintly concave poster. The operculum well-chitinizcd with a short muscular ridge in each corner (lig. 5 c). The secondary aperture is sur- rounded by a prominent rim and lies at some distance from the distal margin of the zooecium, often immediately proximally to the distal two-thirds of the zoa>cium; it is broad, transversely oval. The area of ascopores is situated in a depression and lies more or less far back in the proximal half of the zoa-- cium; it is usually small being contained as a rule two or three times in the secondary aperture. It is divided by a separating ridge into 8—6 partitions and the margin of each of the.se is provided with a number of extremely thin denticles, which usually reach in to the middle of the .section without however meeting.
The gonozooecia, which are scattered sparingly over the surface of the colony, partly singly, partly in groups of 2 — 8, are more than twice as large as the zooe- cia, from which they also differ, in addition to a richer development of pores and avicularia and a much more arched surface, by the possession of a much larger ascopore-area, which shows 16—20 small partitions, and by having a much broader and relatively lower aperture, the proximal rim of which is very convex.
The avicularia, which are provided with a fairly elongated, triangular man- dible, occur both independently and dependently, the former of which have a similar form and size as most of the zomcia, being very sparingly scattered over the sur- face of the colony. On the ordinary zoa-cia there are as a rule three, very often four and sometimes five avicularia. The most constant of these is situated dis- tally to the ascopore-area and its point is directed towards the aperture. One is usually placed on each side proximally to or at the side of the aperture and its point is usually directed in towards the middle line of the zooecium, but its direction varies. One may occur in the distal part of the zocrcium and its point is usually directed towards the aperture and it seldom appears on the |)roxi- mal part of the zooecium. In addition to the avicularia corresponding to the above, 12 may al.so appear on each side of the gonozocccium opposite the ascopore-area.
Of this species I have examined a fragment from Fort Western, Victoria (Miss Jelly), consisting of a two-layered folded plate.
289
Bracebridgia pyriformis Busk. Mucronella pyriformis Busi<, Challenger, Zoology, Vol. X, Part I, p. 155,
PI. XX, figs. 5 a, 5 b. Bracebridgia pyriformis Mac Gillivray, Trans, and Proc. R. Soc. Victoria,
Vol. XXII, 1880 (for 1885), p. 135, PI. II, figs. (J, 7. (PI. XIV, fi-^s. ,3a-3e).
The zooecia, which are as a rule pear-shaped or vase-like and have a circle of widely separated pores somewhat distant from the margin, show over almost the whole of the frontal surface a sharp, wavy, transverse striation appearing in a number of broad, rounded ridges, somewhat curved and running mainly in the longitudinal direction of the zooecium. One of these runs round the whole of the zocecium, whilst another, which encircles the aperture, continues proximally to this as two keels running side by side, which finally run together into one. Be- tween the marginal and the median ridges there are also one or several on each side, and sometimes we can distinguish a number which run obli(iuely inwards and are partially separated by the pores mentioned. The only part of the frontal wall of the zofecium which does not show this characteristic striation is a small, depressed, semicircular or triangular region just i)roximally to the aperture. Mac (lillivray has once found an avicularium on this spot. The primary aper- ture, which has two small hinge-teeth, has a rounded, quadrangular form, and the two lateral margins slightly converging distally meet in an arch, whilst the proximal rim is slightly concave. The well-chitinized operculum is provided on each side of the proximal part with a short muscular ridge. Outside the primary aperture there is a low, but broad, somewhat trapeziform tooth, and between it and the secondary aperture a small, stout, conical projection. The secondary aper- ture is of an elongated, oval form and surrounded by a collar-like rim.
Gonozooecia have not been found.
The avicularia (fig. 3 c) appear on the margins of the colony in a more or less interrupted row. They are stout, strongly arched, with a rounded, trapezium- shai)ed circumference and provided with a fairly short, rounded triangular mandible (fig. 3 d), which has its point directed towards the distal part of the branch.
The colonies are two-layered, branched with compressed branches.
A fragment from Victoria.
10
290
Family Reteporidae Smitl, char, t-mend. (PI. X, lij<s. 1-5; I'l. XXIII, figs. 1-.')).
The zowcia, which are foni])oso(l of a very hard and tliick calcareous nias.s, are as a rule only sparingly piovided with pores and may have 2 — 8 spines, which are not rarely composed of a row of inlernodes. There is a more or less well-developed vestibular arch, which is usually headed, and the separating walls between the single zocpcia are provided with uniporous, more rarely with few-pored rosette-])lales, which may sometimes be placed in the inner wall of small pore- chambers. Each distal wall is usually provided with one and the distal half of each lalcral wall with one unijiorous rosette-plale. Dependcnl (ivhiiUirin of varying form and size occur as a rule. The hyperslomial ixvcin, which spring from a narrow, sometimes almost stalk-like proximal ])art and consist in their whole ex- tent of two calcareous layers, are originally free, though as a rule more or less deeply immersed in niche-like depressions; but in older |)ar(s of the colony they may often be ijuile hidden under the covering layer which grows over them from (he margins of the niche-like depression. Their frontal surface may .some- times be complete, sometimes provided witli a slit-like or trilobed uncalcilied j)art, almost never with scattered pores. An od'cial o])erculum seems to be always absent, but on the other hand the free margin of the oa-cium is not rarely pro- vided with a larger or smaller, obliquely inwards directed, median projection, which serves to reduce Ihe size of the aperture. The colonies are not rarely incrusting, but usually free and in most cases occur in the form of a |)erforated network of sinuous or folded laminte, which only consist as a rule of a single layer of true zoo'cia (almost always directed towards the inner side of the colony). Tlie opposite surface of the colony is however covered by one or several layers of kenozoorid, the inner cavities of which are greatly reduced or quite absent and which agree with the zooecia neither in form nor in size. A larger or smaller number of these keno- zooecia are provided with avicidaria and the colony is fastened according to its age and size by means of a larger or smaller expansion formed by similar keno- zofccia.
This diagnosis of the family is based on the investigation of a large nund)er of species, and the family is undoubtedly one of the most TiaUiral and most sharply defined. Whilst the aperture, operculum and Ihe peristome are subject to large dilTerences, we (ind as a rule distinct hinge-lecth and a more oi' less well-developed vestibular arch, which is usually |)rovide(l in the neighbourhood of the margin with snudl, rounded projections. Such a crenulated arch can be
291
seen on figures of Ret. siiniosa Kirkp. ', Rel. novae zelandiae Waters- and Rhyn- chozoon profundiim Mac Gill.'', as well as on the accompanying figures of Rhijnc. nnyii- latam n. sp. (PI. XXIII, fig. 4 a). In those forms which have a strongly developed peristome, the arch named is difficult to see from the frontal surface and to examine it we must grind down the basal wall of the colony. This also applies to the hinge-teeth. The rosette-plates seem to show great constancy, and in the numerous species I have examined in this regard I have only found two in which the rosette-plates had several pores. Thus, the distal wall in R. lata is provided with a narrow, transversely oval rosetle-plale with a row of 3 — 5 pores and in Rliijnc. an(jnlatum some of the rosette-plates may have two pores. The rosette-plates in this species are exceptionally situated at the bottom of pore-chambers. The ooecia also in spite of smaller differences show great agreement in their structure. The peculiar layer of kenozocrcia, which covers the basal surface of the free-growing colonies and is of the same nature as the expansion attaching them to their under-layer, deserves closer description. With regard to this expan- sion Smitt' has correctly recognised in Ret. elongata (Ret. Wallichidnd Busk), that it consists of imperfectly developed individuals, and he has even found some of them with an aperture. Hincks'' describes these individuals as ^aborted cells«, but as I have already shown in my -Studies on Bryozoa< he" has in so far mis- understood this expansion, that he regards it as the first formed i)ail of the colony, whereas in reality it only arises after a number of ordinary zoa-cia have been formed. It then gradually increases in extent with the further growth of the colony. PI. X, fig. 1 c shows a beginning colony of R. Reaniana, which shows in addition to a primary zooecium in the Memliranipora stage two fully developed zooecia and the basal surfaces of two just beginning. Fig. 1 d on the other hand shows a slightly older colony with a small radical expansion and in figs. 1 g and 1 h parts of this are magnified to a greater extent. Both show beginning keno- zooecia on the growing margin the membranous roof of which has disappeared in the previous boiling in caustic potash; their distal wall is provided with 1 — 2 small rosette-plates. If we examine the outer surface of a Retepora colonj' attached to its under-layer, e. g. the colony of Retepora Reaniana figured on PI. X, 1 a, which is attached by its radical expansion to a tube of Hijdroides norvetjica, we see that the division into irregular, mostly avicularium-bearing areas shown by this expansion is continued without inlerrui)tion or boundary on to the outer side of the free part of the colony, with Ibis dilTerence, however, that these areas
' 49a, p. 26i). - KlSi-, I'l, VII, fifrs. 1— 3. ■' KKS, I'l. II, lif^. 1."). ' 100, p. 200— 201, IM. .X.WIII, lifj. 2:!2. ^ 22, p. .'ISS. '• 22, p. 394, fig. 18.
19*
292
are here somewhal larger and that only a small number of lliem hear avieularia. It seems reasonable lo conehide therefore, that this division into areas is here also a sign, that this covering is composed ol' kenozooecia. Waters, who has extended our knowledge of the Rrijozon on so many points by bringing forward new or insuflicienlly known structural features, has also at several places made investigations on this characteristic division of the covering into areas. Tims, in his paper' on a ])arl of the Brijozoa material of the Challenger Expedition he has called attention lo the fact, not only that it shows stratification but also that it contains numerous cavities. \n a later ])aper'- he has further remarked, that by incineration it can be loosened from the true zoa-cia, and that the lines which divide it into areas are not merely superficial marks but lliat tliey extend right through it. As the incineration bowever makes this covering unsuitable for closer investigation, and boiling in caustic potash, by which means two-layered colonies can usually be divided into their two layers, here leads to no result, there seems no other way of isolating this kenozocecial layer than to grind down the zoo-- cial layer, and tbis I bave done with good results in the case of Ret. tessehda. A fragment of Ret. lain, which was sent me by the British Museum, shows quite exceptionally here and there a tendency of this layer to scale in small plates, and these thus oiTer favourable conditions for a closer investigation. After such a plate has been boiled for some lime in caustic potash, we can by means of a needle isolate the single kenozoa-cia, which thus possess not only independent lateral walls, but also, what is never found in the ordinary zocrcia in any Rrijo- zoci with exception of the Omjctiocella species, independent distal and proximal walls. I have found the same thing in the kenozotrcia of Ret. lesseldla and it will probably prove to be the rule in this family. The above-mentioned kenozooecia of Ret. lata also appear to contain an inner cavity, which however is of an ex- tremely variable and irregular form and consists, e. g. in the two connected keno- zooecia figured on PI. XXIII, tig. 2 a, of a number of small, more or less elongate cavities connected by narrow, canal-like i)arts. The cavities in adjacent kenozooecia are also connected in tbe same way, and the separating walls lluis sbow a corre- sponding number of round openings or rosette-plates. PI. XXIII, (tigs. 2 b, 2 c) shows the same kenozoa'cium seen from the basal (zooecial) surface and from the one side. In the lirst case it shows a large, inner cavity, which however is in parts interrujjled by calcified portions and is not seen with the same distinct- ness everywhere, as it lies at a somewhat difTerent height at difierent places. It is in connection both on the distal wall and on the two lateral walls with the
' no, pp. l'J—2\, ligs. 7,9. - 115, pp. II—IS.
293
adjoining kenozooecia by means of canal-like perforations. On the second figure, showing the lateral wall which has most connections, we find corresponding to these 7 small rosette-plates, the situation of which near to the basal surface shows, that the inner cavity belongs to the oldest ])art of the kenozott'cium, whilst the remaining part of the thickness of the wall has arisen from the later deposited calcareous layers. As Waters' has already remarked, every second layer extends further out than the foregoing and therefore the walls of the adjoining kenozoa-- cia dovetail into each other. The avicularia of the kenozooecia, which are con- nected with the cavities mentioned, send out canals, wliicli partly and often through separating walls stand in connection with corresjionding canals from other avicularia (PI. XXIII, fig. 1 a), and partly open out through |)ores on the outer surface. At the same time as the originally formed avicularia are overgrown by the gradually deposited calcareous layers, new ones are constantly formed, and we therefore find on the frontal wall partly quite superficial, partly more immersed and finally overgrown, though still distinct avicularia (PI. X, fig. a c). As the keno- zooecia are dependent for their nourishment on the zooecia, they must have an internal connection with these, and we therefore find on the basal wall of more or fewer zooecia a small, round opening, which must correspond to just as many rosette-plates on the zoa'cial surface of the kenozoa'cia. In Ret. tesselata, which sometimes consists of two layers of ordinary zooecia (PI. X, fig. 4 c), the quite young kenozooecia contain a large cavity (PI. X, fig. 4 b), but it seems to dis- aj)pear fairlj' quickly or to become reduced (fig. 4 a) and in older zoa?cia to ex- ist only in connection with an avicularium. If we grind down the frontal wall of the zoa'cia in this species, we find on the basal wall a number of pores, which undoubtedly serve for connection with the kenozooecia. Whilst PI. X, fig. 4 b shows the growing edge of a colony ground down transversely, fig. 4 a shows a much older part of the colony similarly treated, and the three rows of cavities seem to indicate that we have here three layers of kenozooecia. That the keno- zotpcia may occur in several laj'^rs, the one outside the other, apjiears even more distinctly from PI. X, fig. 2 b, which represents the proximal part of a colony of Ret. mediterranea ground down transversely. This part, which is seen from the side in fig. 2 a, shows in transverse section three originally separated branches, a narrower and two broader, which have become connected to one mass by means of numerous kenozooecia, which at this place have not only overgrown both surfaces of the colony by several layers, but have also filled up the space between the single branches. On the transsected surface we see a transverse row
' 115, p. 78, I'l. VI, figs. Ga-Gb.
294
of the mostly quadiangularly rounded sections of tlie zoa^cial cavities. Just as the kenozoo^cia mentioned seen from the surface (fig. 2 a) are of very different form and size, the same is the case with their transverse sections, and the inner cavity in some of considerable size is in others almost slit-like, hi two of them (one on the left and one on the right side) there is only a distinct cavity in the one half, whilst in the other the two walls lie close up against one anollier, and this enables us to readily understand why these kenozoa'cia in many species, e. g. in Ret. Beanianu and Ret. phoenicea, have no inner cavity even in the youngest |)arts of the colony. On the kenozocx-cia arranged in layers we can distinguish between three kinds of walls, terminal separating walls which separate the keno- zoa'cia at different heights, lateral walls which separate the kenozoci-cia at the same height and interjacent walls which separate the kenozocccia in different layers. Whilst the last are provided with pore-canals, the two others are |)rovided with uniporous rosette plates (figs. 2 d and 2 e), which according to the extent of the chambers may sometimes be placed in a zigzag row, sometimes in a single row.
That we have here actually to do with layers which arise the one outside of the other, is specially distinct in those cases where for example a Spirorhis is fixed on a Retepnru colony, as the tube of the worm then becomes covered by layers which grow up over it from the surface of the colony. This is seen for example on PI. XXIII, fig. 3 a, which represents a section, obtained by grinding, through a colony of Ret. celliilosa from Oran. We see here a Spirorbis tube cov- ered by an expansion, which on the one side is two-layered and on the other single, whilst on each side of the tube there is an elongated, triangular cavity, which separates the covering layer from that on which the tube rests. On PI. X, fig. 2 c is shown a part of a colony of Ret. medilerranca, which is much younger than the fragment represented in fig. 2 b, but here also the frontal surface of Ibe zott'cia is covered by kenozocecia. Fig. 3 b shows a section, obtained by grinding, through the terminal j)art of a branch of Ret. Wdllichidiui and (he kenozotrcia here also are provided with a distinct cavity.
Time has not permitted me to enter further into the classification of this family, and I have been obliged to restrict myself partly to describe a single incrusting sjiecies, partly to mention a number of earlier described incrusling s[)e- cies, which must be referred to this family. These are for example, Schizotlicca fissa Busk, Schiz. dii'i.sd Norman, Rhijnchozoon^ bi.ipinosiini Johnsf., Rluinch. lonijiro- stre Hincks, Rhi/in-li. pro fund urn Mac (lill., Rliiincli. rrrniildliim Waters, 'Miicronclld tubiilosa Hincks, 'Schizoporellu' arnmld Hincks, Schiz. <^ lucidd Hincks, 'Scliiz.^ scintillans Hincks etc.
' .\s to the name lilujnchozoon see 2.'>, p. 125 and 38 b, Index.
295
Rhynchozoon angulatum n. sp. (PI. XXIII, figs. 4 a— 4 h).
The zooecia, which consisl of a hard and thick calcareous mass and have as a rule a rhombic hexagonal outline, have a strongly arched frontal wall, which rises strongly i'rom the proximal end and from the lateral margins up towards the oral rostrum or the oral avicularium. The margin of the zocrcium is provided with a number of fairly large scattered pores and marks of two spines are some- times seen distally to the aperture, which is approximately terminal. The aper- ture, which is provided on each side with a more or less developed, as a rule stout, conical projection, is almost circular in the greater part of its circum- ference, but provided on its proximal margin with a slightly developed, low^ rounded sinus. This on each side is bounded by a large, compressed cjuadrang- ular hinge-tooth, the distal edge of which is provided as a rule with a small in- cision dividing it into two lobes, only one of which can be seen from the frontal aspect. From the distal rim of the aperture and a part of the lateral margins arises a well-developed vestibular arch hanging down into the zoQ?cium, which is provided on its oral surface near to the free margin with a row of small, pearl-like nodules. The strongly chitinized, yellow operculum has two, small, muscular pits on its distal half and is provided on each side of the slightly marked sinus at the margin with an obliquely semicircular, thin region, arising from the fact that this part has l)een in connection with the hinge-tooth. Each distal wall is provided with 2 — 4 and each lateral wall in its distal half with 3 (2 — 4) uniporous or partly biporous rosette-plates, each of which is situated in a small pore-chamber.
The ooecia, the proximal part of which is very narrow, almost stalk-like and gradually increases in width distally, have their basal part immersed in niche- like hollows, the distal and marginal parts of their unperforated frontal surface being furnished with an oa?cial cover arising from the distal zorecium and end- ing in a curved or angularly bent proximal margin. The uncovered portion, the greater part of which is of a yellowish colour, ends in an obliquely inwards di- rected (fig. 4 f) trapeziform part with a straight proximal and incurved lateral margins.
Avicularia. A somewhat compressed avicularium, which is large, arched and almost triangular in section, is found on one or other side of most zooecia in the neighbourhood of the proximal rim of the aperture; its fairly long, triang- ular mandil)le is directed oblicjuely outwards. In a smaller number of zoo-cia an avicularium is either wanting or is placed on the proximal half of the zoa-cium.
296
and in both cases the proximal rim of the ajjerture runs out into a sloul ros- trum directed somewhat distally.
This species which occurs along with 'Schizoporella' scintillans incrusts like that species oyster shells, from Stewart Island (Miss Jelly). It is nearly related to Rhymhozoon bispinosiim and Schiz." scinlillaihs, which must likewise be referred to the genus Rlnjnchozoon, and to judge from the species mentioned this genus seems to be characterized by the possession of a more or less well-developed sinus on the aperture, by its oa'cia which have an entire frontal surface and are provided with an incomplete on^cial cover and by the possession of pore- chambers. In Rhync. scintillans however the operculum is provided with a strongly developed accessory part, the hinge-teeth not being in connection with the inner surface of the operculum but wilh its free margin.
Family Myriozoidae Smilt., char, emend.
The zoa-cia, provided with a covering-membrane and more or less thicU-wnlled, always lack spines and are furnished with numerous, sometimes more scattered, sometimes more closely placed pores, , which in the very thick-walled forms appear as long canals. Both the distal wall and the lateral walls which are com- mon to the adjoining zocEcia are provided with uniporous rosette-plates, which usually occur scattered, more rarely in uniporous pore-chambers. Dependent ani- cularia seem always to be present. The o(vci(i are as a rule hyperstomial and con- sist of two calcified layers free in their whole extent. They arise from a broad proximal part, are immersed in niche-like depressions and their frontal wall is covered and as a rule quite concealed by an oa?cial cover originating from the cryptocyst of the higher situated zoa>cium. More rarely they are endozoa?cial. The colonies are seldom incrusting, as a rule free, usually branched with cylindrical branches, sometimes laminate.
Busk has instituted a genus (iejiluir<>j)h()r(i, iiud the most significant part of the generic definition is the following: »A prominent avicularian process on each side of the orifice, the two eventually inarching and forming a bridge in fionl of il«. This character, however, is not sufficient for the establishing of a new genus, as the bridge named is identical with that found iu the species of the genus Hasivellia. In the genus Adeonella as well as in the genus Haswellia the peristomial pore is formed in such a way that two jieristomial processes unite to form an arch in front of the aperture. In Hasiv. auslraliensis, Hasw. auriculata and Gephyrophora polymorpha each of these processes is provided with an avicu- larium, but while this in the two former species is very small in proportion to the process on which it is sealed, it is in the latter so large that the process may
297
seem to be only a part of the aviciilarium. The case is however quite the same. Nevertheless the genus Gephijrophora may perhaps be preserved on account of its possessing endozooecial ooecia.
This family is nearly related to the Reteporidae, from which they dilTer by the absence of spines, by a richer development of pores, by only possessing a weakly developed vestibular arch as also by difTerences in the structure of the ooecia. It is possible, however, that closer study of a larger number of forms of both fa- milies will prove it ditTicuH to define them sharply from one another.
Synopsis of the genera. \
1) A tubular peristome provided with two or moi-e avicularia and with a suboral pore leading into the periston! ial cavity:
2) Hyperstomial otx'cia Haswellia Husk.
2) Endozod'cial oa'cia Gephijrophora Busk.
1) No peristome (hyperstomial ocrcia):
;5) Avicularia without transverse bar; pore-chambers Mijriozoflla n. g.
(Mijr. criislaceiim Smill.)
3) Avicularia with transverse bar; no i)ore-chambers Mijriozoum Donati.
Haswellia australiensis Hasw.
Haswellia australiensis Busk, Challenger, Zoology, Vol. X, Part I, |). 172,
Fl. XXIV, fig. 9. Porina coronata var. iabrosa Waters, Challenger, Zoology, Vol. XXXI,
Part III, p. \V1, PI. II, fig. 8. (IM. XVI, ligs. 2 u-2 b). The zooecia elongated, narrow, without separating furrows, provided with nu- merous pore-canals, the outer, oval openings of which are separated by arched ridges and show a more or less distinct tendency to be arranged in longitudinal rows. Whilst these openings in the younger parts of the colony are l)roader than or as broad as the ridges, they decrease in extent as time goes on and finally become quite closed. Each pore-canal ends inwardly in a uniporous rosette-plate with a calcified outer area. The operculum is well-chitinized and its anler makes the two-thirds of a circle. The accessorial part which is only separated from the anter by a very small rounded sinus on each side is rather large, rounded trian- gular and the lateral margins are a little concave. A very little indistinct muscu- lar dot is placed on each side in the distal part of the operculum. The hinge-teeth are well-developed. The fairly short, obliquely projecting oral tube, which posses- ses only a small number of scattered pores, has an opening medially on its proxi-
298
mal wall, which is soniewhal smaller in the on^cia-bearing zorrcia than in the others, and the bridge se[)arating this From the secondary ajjcrturc is provided at its distal part with two small, triangular avicularia. Each distal wall is provided over its whole surface with uniporous rosette-plates, which are silualed at the end of long canals owing to the thickness of tiiis wall. Each lateral wall and each inner wall is provided with a smaller number of similar jjlates. on the lateral walls as a rule 2 — 3, whilst there may be up to 6 irregularly scattered i)lates on the basal wall. The outermosi part of each lateral wall is further perforated by the inner terminal parts of a number of pore-canals, some of which end on the surface of the zoo'cium, others on the distal wall. These inner terminal ])arls are sometimes l)ifurcated, sometimes sac-like widened, but always have two separate, uniporous roselle-[)lates, which belong each to its own side of the separating wall and these marginal rosette-j)lates thus form a connecting link between the com- mon lateral rosette-jjlates and those belonging to the frontal wall.
The ocecia in conjunction with the peristome form large, mamma-like ])n)tu- berances which are not sharply marked off from the zon?cia and they seem usually to occur on all zoo'cia in one or in several (up to (>) successive circles, more rarely only on one or several zocrcia in one circle. Whilst the single ocrcia are originally separated from their neighbours by fairly distinct depressions, they gra- dually fuse together almost entirely to form ring-shaped swellings, which make the oo-cia-bearing branches easily recognizable. The oo'cial cover, which like the rest of the zoa'cium is provided with pore-canals, is connected with the distal wall of the oral tube, and through the secondary aperture can be seen the frontal wall of the actual ocecium formed by two calcareous layers, which can only be seen distinctly in longitudinal sections obtained by grinding.
The avicularia are fairly small, of a pyriform outline and provided with a triangular mandible. A somewhat larger avicularium, the ascending, freely pro- jecting point of which is directed proximally, is situated as a rule on the boun- dary between everj' two zoci'cia a little proximally to the peristomial pore, whilst a smaller immersed avicularium is situated on each half of the bridge which separates this pore from the secondary aperture. The two avicularia, the points of which are directed towards each other, are separated medially on the bridge by a faint depression and not by a tooth-like projection as in the colony exam- ined by Busk.
The colonies are richly branched with irregular, bifiircaled, cylindrical bran- ches, on which the zod^cia aic arranged in whorls round a small, cyliiulrical cavity, thus giving rise to inner walls. The colonies are from the Formosa Chan- nel, Lai. 2'6'> 20' N., Long. 18" 30' E., 17 fathoms depth (Andrea).
299
Haswellia coronata Reuss Cellaria coronata Rcuss, Fossile I'olyparien d. Wiener 'rerliiir beckens, Haidinger Naturwiss. Abhandl. 2ter Band, 1848, p. 62, T. VIII, fig. 3. Eschara gracilis Lanix. Encyc. mclli. p. 375.
(PI. XYt, iii;. I I)).
The zocecia elongated, without distinct separating furrows, wilii numerous .scattered pore-canals, which have an inner wholly uncalcified rosette-plalc. The well-chilinized oi)erculuin, Ihe j)0ster of which is not distinctly separated from the antcr, may he called broadly egg-shaped, as it decreases evenly in breadth in its i)roximal hall". It is provided within Ihe margin on each side with a ridge- shaped thickening, which disappears both dislally and proximaily. There is a hinge-tooth on each side. The secondary aperlure is i)road, transversely oval, but has a bean-shaped appearance, because the inner surface of the perislome-tube is provided a little within the proximal margin of the aperture with a low, but broad, triangularly rounded projection. The peristomial pore is elongated in the ordinary zocEcia and round in the ooecia-bearing ones. Each distal wall has nu- merous, uniporous rosette-plates, which owing to the thickness of this wall are situated at the end of long pore-canals. The distal half of each lateral wall is provided with 2 — 3 scattered uniporous rosette-plates situated at the end of short pore-canals, which perforate the wall iii an oblitiue direction, so that the rosette- plate lies on the internal surface of the wall and the entrance to the canal on the external. As in the preceding species the outer part of the lateral wall is perforated by the inner end of a number of pore-canals.
The ooecia as in the foregoing species are large swellings not sharply marked off from the distal zocrcium. The peristomial pore is round and the projection appearing within the secondary aperlure in the ordinary zoircia is wanting or weakly developed.
The avicularia, which are very small as a rule, generally seem to have a rounded form. On the circumference of the secondary aperture there are as a rule 1 — 3 more or less projecting on the distal margin and 1 — 2 on the proximal. One is also present as a rule on each side or only on the one side a little more prox- imaily, almost halfway between the aperture and the peristomial pore. The last may sometimes reach a fairly considerable size and then have a broadly rounded, somewhat lyre-shaped 0])ening. Further, there may also be 1 — 2 in the proximal part of each zooeciuni. Round the aperlure of the oa'ciuni-bearing zocecia the avicularia are always in smaller number and may sometimes be quite wanting.
300
The colonies hifurcakMl, with lairiy broad, compressed, Iwo-layered branches. Two colonies lioni \'ictoria.
Hasiv. nuriciihtta Bnsk ' which lliis anlhor willi some iiesifation lel'eis to the genus Hasiiicllia, doubtless belongs to tiiis genus and is most nearly rehilcd to lUisiv. (lustraliensis. As in this species the bridge dividing the suboral ojjening from the secondary aperture is provided with two small avicularia (PI. XIX, (ig. 17 a). I have examined a fragment from the Challenger station 13') c.
Gephyrophora polymorpha Busk. Gephyrophora polyniorj)ha Husk, Challenger, Zoology, Vol. X, Part I, p. 1(57,
PI. XXXIV, fig. 2. Schizoporella polymorpha Waters, Challenger, Zoology, Vol. XXXI, Pari III,
p. 29, PI. II, figs. 21—24.
The zocecia, usually tongue- or lyre-shaj)ed, are fairly strongly arched, sepa- rated by distinct sutural furrows and provided with fairly densely placed, short pore-canals with a large inner opening. The well-chitinized operculum which is provided with two muscular dots is of an oval outline and the small accessorial part has a rounded poster, which is separated from the anter by a not very sharp bend on each side. The hinge-teeth are well-developed. The two lateral halves of the low, ring- or wall-shaped peristome are connected with each other by a strongly projecting, compressed arch, formed by the coalescence of two originally distinct processes, each bearing a large avicularium. Its central pari which separates the j)oints of the two avicularia has in most zod'cia the form of a large, projecting, cjuadrangular plate. The perforation lying between the bridge and the proximal part of the aperture corresponds to the peristomial pore in Hasivellia and as in the sjjecies of that genus is much larger in the ordinary zoa>cia than in those bearing oa'cia. The distal wall and the lateral walls, which are thin, are provided with a large number of scattered, uniporous rosette-plates.
The ooecia, which are present in very large number, have when seen from the surface of the colony a similar appearance as in tlu' two species described above, appearing as large, indistinctly marked olT swellings which are either pro- vided with pores over their whole surface or do not have these on a median part. They are however considerably more elongated than in the species of the genus Hasivellia and in fact have quite a different structure. Thus, as Waters has shown, their zoa>cial half is immersed into the cavity of the zocecium itself. They have an unusually elongated form for otvcia and a thick cryptocyst layer is
' 8, p. 173.
301
inserted between the membranous eclooa^cium and the calcified endoooecium. From Waters' statement^ regarding tliis ort'cium : »I propose to call this a con- cealed ovicell, retaining the expression immersed for those which give an external indication of their presences one would conclude that the oa'cia in the specimen examined by Waters were not distinctly seen on the surface of the colony.
Avicularia. The peristomial arch is on each side provided with a large, robust, triangular, obliquely ascending avicularium, and the broad, trapeziform proximal part of the mandible grades over into an elongated part, the two, almost parallel lateral edges of which finally run together in a stout terminal hook.
Of Ibis species I have examined several colonies with labyrinthine-like branch- ings and round or compressed, two-layered branches from the Cape and Port Elizabeth.
To the genus Mijriozoiim belong the species M. tniiiccitiini, M. coarcliiliini, M. siib- gracile and probably also the species described by Busk," M. hoiioliilense, M. simplex and M. marionense, in the last of which the oa'cial cover only reaches halfway down over the frontal surface of the oa'ciuni. To this genus I must also refer the two-layered, laminate 'Esclutroides-^ occliisa Busk^ and the one-layered ySchizoporeUn« hitiirrita Hincks,^ which shows several points of agreement with Geplujrojihont pohjmorpha. The genus Mijriozoella is only represented by a single species, the incrusting M. cnislcicea Smitl.
Family Sclerodomidae n. f
The zou'cid, which have a covering membrane but no spines, are very thick- walled and consist of a very solid and hard, finely striated calcareous mass, which is perforated by pore-canals, sometimes scattered, sometimes arranged within the lateral margins. The very small distal wall is provided with a number of uni- porous rosette plates and the lateral walls with a varying number of rosette-plates with few (2 — 3) pores. There is a membranous or weakly chitinized operculum and a more or less well-developed peristome. Dependent (uncubtriii are present and are frecpiently situated within or outside the peristome. The hyperstomial o<vcia, which have a membranous ectooa>cium, are only distinct on the surface of the colony in quite the youngest zowcla, as they are quickly covered over by a thickened layer or by the peristome. The colonies are free, branched.
Genera.
The peristome is funnel-shaped, immersed, not projecting, provided with avicularia; no peristomial pore; in the oo3cium-bearing zooccia
• 110, p. 29 — .•!0, in. II, figs. 21—24. - 8. p. 1711. ' 110, p. 26. ^ 29, p. 280.
302
the distal wall is provided with an cxj)aiision ending in a thickened, crenulated margin, which partly separates the oa'ciiun IVom the zo-
cecium Scierodomus n. g.
(Bil'axaria Busk, p. p.) The peristome is tube-sliaped, projecting, without avicularia, pro- vided with a median opening; in the orecium-bearing zoo'eia there is
no expansion oi' the distal wall Tessarudoma Norman
(Porina d'Orb., p. p.)
S. denticulatus Busk. Bifaxaria denticulata Busk, Challenger, Zoology, Vol. X, Part I, 1884,
p. 82, PI. XXIV, fig. 3. Bifaxaria denticulata Waters, Challenger, Zoology, Vol. XXXI, Part III,
1888, p. 15, PI. II, fig. 31. — — Waters, Exped. Antarctic Beige, Bryozoa, 1904,
p. 59, PI. VIII, figs. 14 a, h. (PI. XIX, figs. 18a-18c, PI. XXII, fig. 14 a). The zooecia indistinctly separated, elongated, thick-walled, strongly arched, increasing evenly in width irom the narrower, proximal end and oblicjuely ascend- ing towards the secondary, terminal aperture, which at a certain age forms almost a right angle with the proximal part of the distal zoan'ium. They consist of an extremely hard and solid, finely striated calcareous mass, which is provided with as a rule fairly densely placed, round or oval, scattered pores leading into long, more or less curved canals. As the colony gradually increases in thickness these pores come to he situated at the bottom of narrow, channel-like concavities, which increase considerably in length with age and give the surface of the colony a characteristic, grooved or longitudinally furrowed appearance. In (juite young zon'- cia the pores may even sometimes be extremely rare in a median belt along the frontal wall.
I have not been able to determine the form of the primary aperture, nor liave I been al)le to find any operculum. In the youngest, undamaged zoa-cia I have been alilc to find, there is a secondary, more or less regular, broad but low, semicircular aperture, within the proximal margin of which there is a low, but broad, oblicpie tooth-like projection (PI. XXII, fig. 14 a), which on the one side grades into the lateral margin of the aperture and becomes gradually higher towards the other side, where it ends in a rounded, rectangular or obtuse-angled edge not far from llie lateral margin. With the exception of cpiile few zoa>cia, in which an outer, perislomial avicularium is wanting, the peristome in the younger
303
zocecia is swollen proximally and divided by an almost rectangular incision (fig. 14 a) into two, unequally large halves, the larger of which bears a fairly large avicularium, whilst the smaller is as a rule provided with a rounded swelling provided with some pores. As calcification increases, the incision mentioned en- tirely disappears, the aperture becomes circular and the avicularium comes to be placed deep within this. The very snuill distal wall, which is provided with ca. 7 scattered, uniporous rosette-plates, is in the oa>cium-bearing zocecia continued into a plate-like expansion ending in a thickened, crcnulaled margin (PI. XIX, figs. IS b, 18 c), and a partial separating wall is thus formed between the ooecium and the zooecium.
Avicularia. As a])ove mentioned, an avicularium is placed in the incision on the peristome. It springs from the neighbourhood of the free corner of the tooth- like projection and its triangular, rounded mandil)le takes an obliquely distal direction. There is also a second avicularium, which is only seen on grinding down Ihe one half of the zowcium, as it is situated deep down on the inner sur- face of the peristome, almost at a level with the proximal part of the oa^cium. The mandible, as also in the second avicularium, is fairly short, triangular and as a rule situated transversely to the longitudinal axis of the zocecium.
The ooecia, whicli had already been found by Waters and which occur on numerous zoa?cia, arc for the most part hidden, partly by covering layers and partly by the peristome, and only the proximal part of their frontal wall can be seen more or less deeply within the secondary aperture as a dependent fiat part from the distal portion of the latter. This flat dependent part ends in a straight or weakly curved edge and is divided into two lateral areas by a narrow, median belt, which is possibly a calcified portion of the ectoorecium. In sagittal sections they show an elongated, helmet-shaped form (PI. XIX, fig. 18 b).
The colonies, of which I have examined a number of fragments sent from the British Museum, are free, branched, with the zorecia arranged in -t alternating rows. The separate branches show as a rule a distinct contrast between a more strongly arched frontal side and a somewhat flatter basal side. Of the 4 zoo'cial rows two open on the frontal side, whilst the two others have their openings on the margin of the branch, and from the frontal aspect of the branch we can at the same time see three rows of apertures, whilst from the basal aspect we can only see two.
Challenger St. 320.
Waters' places Piistiilipont ruslica d'Orb. and Releporellti nujriozoiiles' in the
' 115, p. ()0 — Bl.
304
neiglihoiirliQod of this species, and lo judge I'lom lius author's description of Sijsteiiopora contractu ', I must also refer this form to the family Sclerodomidde. It agrees with Sclerodomus denliciihilns in the numerous, scattered pore-canals, the cov- ered-over ooecia and in the possession of an avicularium on the inner surface of the peristome. The species descrihed hy Waters under the generic name of Cellcirin- e//a ' should also he referred to this family, and the author himself is also almost inclined to place them in the neighbourhood of .Sys/e/jopora. To this familv, lastly, I must also refer Tessaradomci tn>rc(dis, which consists of a (juite similar, hard and solid, finely striated calcareous mass as is found in Scterodomns denlicid(dus, with which species it further agrees in the covered-over oa-cia and in the structure of the rosette-plates. Another species of this genus is described by Waters- under the name of Porina prolwscided.
Of the remaining species which Busk refers to the genus Bifaxaria I have only been able to examine an extremely small fragment of Bif. cornujata, and there can be no doubt that this species belongs not only lo another genus but even to another family than Sclcrodamm dentictdaliis. The thick -walled calcareous mass, which is only perforated by some extremely fine, slit-like pores, seems to be somewhat brittle. The separating wall between the two zoa-cial rows has a row of small, uniporous rosette-plates within each lateral margin, the avi- cularia seem to have no transverse bar etc. The slight information given by Waters^ concerning the ocecia seems lo indicate, that these are transformed zod-- cia. All seems to show, that these forms take up a special position and a new description of them is very necessary.
Family Tubucellariidae Busk. The zonrcia, which are covered by a membrane and have no spines, are more or less thick-walled and provided with densely placed pits or areas .separated by ridges, each surrounding a pore. The lateral walls which are common to the adjoining zoo^cia are provided with a number of, as a rule scattered, multiporous rosette-plates. AvicLdariu may be present. The ocvcia* are at the end open spaces, formed by a strong expansion of the i)eristome (perislomial oa-cia), and in the hitherto known members of this small family an ascoi)ore is found. The col- onies form either richly branched, jointed tufts or free, Ibliaceous one-layered expansions.
' 115, p. 56—57. - 115, p. 3i). ^ 110, p. 15. ' IIG.
305
Genera.
A more or less prominent tube-sha])ed peristome, proximally to which is found an ascopore:
A simple separable operculum, no vestibular arch, no avicularia
TubiicelUtria d'Orbigny.
A membranous opercular valve (?), a vestibular arch, each zoa-cium with one or two avicularia at the height of the ascopore Tubipordlu n. g.
Tubucellaria opuntioides Pallas.
Busk, Challenger, Zoology, Vol. X, part 1, 1884, p. 100,
PI. XXIV, fig. 7, PI. XXXVI, fig. 19, pars.
(PI. XVI, figs. 4 a— 4 d).
The zooecia elongated rhombic, arched, surrounded by weakly projecting edges. The pore-pits, which have a very small pore, are round or oval, and their network of separating ridges is beset with fairly large, scattered tubercles, of which 3—6 may surround each single pit. The obliquely ascending, tube-shaped peristome, which as a rule has a circular aperture and the distal wall of which is only to a small extent freely projecting, is contained 5 — 6 times in the length of the actual zoavial tube. It shows a number of more or less sharp longitudinal ribs, the furrows separating which contain 2 — 4 larger or smaller pits. Proximally to the peristomial tube there is a more or less distinct, narrow, curved ridge (fig. 4(1), which connects the two marginal ridges. A little proximally to this lies the ascopore, which is surrounded by a more or less prominent, wall-like margin, often beset with tubercles. Its opening on the inner surface of the zooecium is provided with a distal, arched, half-roof. The somewhat ascending distal wall is provided with a large, triangular, oval or trapeziform, multiporous rosette-plate, which is divided by a network^ of ridges into a number of larger and smaller areas. The distal half of each lateral wall bolh on its abaxial and on its adaxial part is provided with 2 — 4 scattered rosette-plates with 2 (1)— 6 pores, so that not only two neighbouring zocccia, but also two zooccia placed at the same level and separated by a neighbouring zocrcium are thus connected with one another by means of rosette-plates. The operculum which is not strongly chitinized makes a segment a Utile larger than a semicircle and the two lateral margins are feebly convergent towards the proximal margin. A very low, almost rudiment- ary opercular arch is placed a little distally to the median part of the operculum and a muscular process is found on each side within the lateral margin.
•20
306
The ocecia, which may almost reach the same size as the zooccia, have the I'oim of rohiist cones inclined distaliy and somewhat inwards and enclose an almost elliptical cavity. Their surface is provided wilh numerous, more or less sharp and regular longitudinal ridges, the furrows hetween which contain pore- pits.
The colonies jointed, richly hranched, with cylindrical inlernodes the length of which is 15 — 18"^™. They have 8 — 10 longitudinal rows of zooecia, with ca. 13 in each longitudinal row.
Port Elizabeth (Miss Jelly).
Like Busk' I regard the Mediterranean species '/'((/'. ccrenidcs as a distinct species.
Tubucellari'a hirsuta Lamour. Busk, Challenger, Zoology, Vol. X, part 1, 1884, ]). lUO, I'l. XXXVI, fig. 18.
(I'l. XVI., fig.s. 3a-3e).
The zocecia rhombic-oval, strongly arched, not surrounded by marginal rid- ges. The pore-pits (fig. '^ e), which are elongated, drop-like, are provided at their proximal ends with a very small pore and the walls surrounding the pits are beset with numerous small, but fairly high tubercles, 8 — 10 of which surround each pit. The ohlicpiely ascending peristome, the aperture of which is transversely oval and its length contained 3 — S'/s times in that of the zoa-cial tube, may he more or less distinctly striated by faint longitudinal ribs beset with tubercles, and except in the two distal zooecia in each internode its distal wall is only to a small extent freely projecting. The ascopore, which is situated somewhat proximally to the peristome, is surrounded by a horse-shoe-shaped wall beset with tubercles with the incision directed towards the peristome, and it is continued on the inner surface of the zoffcium as a short, free tube increasing in width inwardly. Im- mediately proximally to the peristome there is on each side a low, but fairly broad, arched, conical chamber, separated from the cavity of the zoa-cium by a multiporous rosette-plate which is divided into a number of unipoions areas (fig. 3 d) by a circle of calcareous ridges (fig. 3 d). This chamber medially on the frontal plate is ])rovided with an opening and from it rises a distaliy directed, hollow, slightly calcified tube which may be called a radical tube. In a number of the proximal internodes of the colony other tubes appear on some few (2 — 3) of the proximal zoa>cia in addition to those mentioned; these tubes are widened
' 8, p. 100.
307
at the ends and bent like a liook. On a single inlernode there niaj' be up to 6 and they arise from (juite similar small chambers, which may sometimes be situated alongside the otliers, sometimes further down on the zooecium. Each distal wall is provided with an oval, multiporous rosette-plate and the dislal half of each lateral wall with 2 — 3 plates witli 2 -G pores. In contrast to T. opuntioides these rosette-plates appear only on the abaxial part of the wall. Tlie operculum (fig. 3 c), which is shorter than that of T. opuntioides is not strongly ehitinized and has no chitinous arch. The two rounded lateral margins converge distinctly towards the proximal margin and a strong muscular process is placed within each of them.
The ooecia, which resemble the front part of an antique lamp, project more prominently but are less bent upwards and inwards than in the preceding species. They enclose a triangular, rounded cavity and their outer surface is distinctly striated by longitudinal ridges, the separating furrows of which especially in the proximal part contain numerous pore-pits.
hi the colony each internode has a length of 4—5™™-, and in each of the 4 longitudinal rows there are 3 — 5 zooecia.
Port Phillip, Victoria (Miss Jelly).
In the species of this genus the colony is formed on quite the same lines as in the si)ecies of the genus Cellalaria, and we may refer therefore to what has been said on p. 212, as also to the figs. 4 a, 4 c of Pi. VII, which give longitudinal and transverse sections of such colonies.
Tubiporella magnirostris Mac Gillivr. Porina magnirostris Hincks, Annals Nat. Hist., 5 ser. XIV, 1884 p. 279, PI. IX, fig. 6.
(PL XVI, figs. 5a-5(l). The zocEcia, which have a rhombic outline and a very uneven, but not strongly arched surface, are often partially separated from each other by very large and deep, irregular depressions, but not by distinct, regular sutural furrows. The pore- pits (fig. 5 c) at their bottom each have a large pore and their separating, arched network of ridges is beset with large, scattered tubercles; they soon change to deep pore-canals. The distinctly protruding, obliquely ascending, distally directed, cylindric-conical peristome, which has a somewhat concave frontal wall, is not much shorter than the actual zooecium, and its aperture has a triangular, rounded form, as we can distinguish between a more strongly arched anter and a more slightly arched poster. It is provided to a varying extent with scattered tubercles, which appear most numerously and may often be greatly lengthened on the distal
20*
308
part. On the other hand, it may quite lack pore-pits, or these may apj)ear to a number ot one or two. Immediately proximal to it is seen the more or less protruding, cylindric-conical ascopore. I have not succeeded in finding an operculum in the dry colony examined, and it niaj' be concluded therefore that the operculum has been membranous. When the basal wall of the colony is ground down, there is seen a wcll-develoj)ed vestibular arch (fig. 5 b, 5 d). The very thick basal wall of the colony, which does not show zo(tcial boundaries, is covered with numerous larger and smaller tubercles and perforated by i)ore-canals, which may have a larger or smaller opening. From the cavity of the zoa'cium they arc separated by multiporous rosette-plates, of which 5 — 8 maj' appear irregularly scattered. Each distal wall is further provided with 3—4 and the distal half of each lateral wall with 2 — 3. The number of pores in each plate lies between 4 and 12.
The ooecia (figs. 5 b, 5 d), which appear in fairly large nundjer, are easily recognised from the peristomial tubes of the ordinary zocecia by projecting straight outwards (not obliquely ascending) and by being arched, crater-shaped, with as a rule a transversely oval aperture; they are richly provided with pore-pits. It must also be remarked, that the appertaining gonozoa^cia have a very narrow distal wall and often have no avicularia. The ooecium-bcaring zoa-cia ai)pear very distinctly amongst the others on grinding down the basal half of the colony, as it is only possible to see the outer aperture in them from the basal side; this aperture in the ordinary zoa-cia being hidden by the obliquely ascending peris- tome (fig. 5 b). The ocrcia rarely occur singly, but as a rule in shorter or longer transverse rows scattered at greater or lesser distances over the surface of the colony.
The avicularia, which vary very considerably in size, appear as a rule either singly or doubly on each zoa'cium, in the latter case one on each side. They are situated at a level with the peristomial pore, and the chami)er which is freely projecting at least in the younger zoa-cia has its point directed obliquelj- outwards and upwards. The mandible, which is broadly triangular at the proximal part, runs out in a long, bent point.
The colony occurs as a free, foliaceous expansion with a single layer of zocecia.
Port Phillip (Miss Jelly).
Family Conescharellinidae n. f.
Sclenariidae Busk p. p. Schizoi)orcllidac Mac Gilliv. p. p. The zocecia, which are provided with a covering membrane and always lack spines, are in contrast to the general rule so placed that the proximal part of
309
the operculum conuected with the hiuge-teeth is directed towards the growing margin of the colon}'. The separating walls, which are all single, are provided with small, uniporous rosette-plates, and the length of the frontal surfaces, which are not distinctly marked olT from the surface of the colony, is considerable less than the depth of the zoa'cia. Immediately distally to each zoa-cial aperture there is a pore which leads into a cavity in tlic frontal wall. Dependent auiciilaria appear in all the species and in most of them peculiar, likewise dependent keno- zod'cia of unknown significance, liuui'dd, the frontal wall of which is [)rovided with a crescent-shaped slit. Freely projecting, helmet-shaped oa'cia may appear, which seemed to be formed by a single calcareous laj'er and to ha\c no covering memlirane. They arise from the distal part of the peristome and may provision- ally be called peristomial.
The colonies in the hitherto found species are free, either laminate, with the zooecia arranged in two layers or they have the form of a low cone or arched disc, the arched surface of which is formed by a layer of zooecia, whilst the inner and basal surfaces are formed by avicularia arranged in layers.
Whitelegge' who has given a synopsis of the hitherto known species ex- presses the supposition in his short paper, that a closer examination of these forms will lead to a new family being formed for them, and although one of the main reasons of the author for this supposition is liased upon inaccurate examin- ation, his conclusion is cjuite correct. Among the characters given in the above diagnosis he lays stress on the presence of the peculiar pore and the cpiite ex- ceptional orientation of the zooecia.
The characteristic kenozocrcia, for which we propose here the name lun(rcia< (PI. XXIII, figs. 7 a, 7 b, PI. XXIV, fig. 1 a), are like the frontal avicularia small, dependent chambers, each of which is connected with a zooecium by means of a uniporous rosette-plate. Their frontal surface is provided with a crescent-shaped slit with the convexity turned inwards towards the centre of the colony. Further, these lunoecia, concerning the significance of which I can ofTer no definite opinion, occur in somewhat small numbers and are found both in the oldest and the youngest parts of the colony. Their position with regard to and connection with the zooecia are most readily understood when we grind down the flat basal part of the colony in one of the more flatly arched species, e. g. Conescharellina phil- ippensis (PI. XXIV, fig. 1 a). We then readily see that both the luna-cia as well as the avicularia are separated by a wall from the zooecia and that this wall is provided with a uniporous rosette-plate. Further, all these superficial chambers
' J17.
3in
seen in the wliole colony seem to be in nuilual connection witli each other, often l)y means of a narrow, tube-shaped prolongation, and through one or several of these they seem as a rule to open out on the surface of the zocccia.
hi the above-cited work Whitelegge puts forward the extremely peculiar view, that in these forms in contrast to what is known in all other calcilicd Brijozod the new zooccia arise scattered amongst the fully developed and that the chambers which are here called lunoecia are just such rudiments of new zoax'ia, which according to the author may arise both in the oldest and youngest [)ails of the colony. This view is however quite incorrect and is in complete conllict with my investigations on these chambers. Further, it is readily seen that the new zonecia in all members of this family are formed at the free margin, and even the idea that new zooecia can be intercalated between the older in a well- calcified Bryozoa colony is so improbable that I have no hesitation in declaring such a process impossible. The improbability is further increased in that a nnmbei- of these species have a very regular form, which is conditioned just by a regular mode of growth. Mac Gillivray' does not hesitate to accept ^\'h i telegge's sup- position, but with the modification that new zoo'cia according to him arise also between the marginal zoo-cia. In the species of the genus Coneschdrelliiut at the same time as new zoa'cia arise on the margin of the colony, the inner cavity gradually be- comes filled with small avicularia, which stand in connection with the zocrcia and with each other by means of small uniporous rosette-plates, and a longitudinal section through such a colony shows them to be arranged in horizontal layers. The small pore situated immediately distally to the aperture and which according to White- legge is covered externally by a membrane, leads into a small cavity in the wall of the zocrcium, which sometimes projects on the inner surface. The ooecia, which have hitherto only been found in ConeschurcUinii phUippensis and C. cancellata (PI. XXIII, figs. .S a, S b), occur in the latter species in very small numbers and usually in the neighl)ourhood of the free margin of the colony. Their outer aper- ture leads into a space formed by the peristome, at the bottom of which is the zooecial operculum.
The rule in this familj^ that all the other separating walls are single holds true also for those sejjarating the zoci'cia in the two ojjjiosite layers in two-layered colonies. In these further the zoa-cia of the one layer extend in between those of the opposite layer in such a manner, that a section through the thickness of the colony shows the zoa>cia in the two layers to be separated by a zigzag line.
How far the division of the genera |)roj)ose<l here is natural must be deter- mined by investigation of a larger material.
' 76, p. 88.
311
Synopsis of the genera.
1) The colony with hinnecia:
2) The colonies which have the form of a hjw cone or an arched disc only show a single layer of zofpcia, whilst their inner cavity is occupied by numerous avicularia placed in horizontal layers; (ocecia
may occur) Cnnescharelliiui d'Orh.
2) The colonies are plate-like or fan-shaped, with two layers of zooecia; (ooecia are not found) liipora Whilelegge.
1) The colonies, which have no luna'cia, are plate-like, two-layered; (no O(rcia) FlahelUpora d'Orh.
Conescharellina angulopora Tenison -Woods.
Bipora angulopora Whilelegge, Annals Nat. Hist. (5 Sen, Vol I, 1888, p. 18.
(PI. XXIII, figs. 7 a-7 f).
The primary aperture is elongated oval, distnlly rounded, proximally pointed and here provided with two elongated, rounded, triangular hinge-teeth, which bound a narrow, elongated sinus. The peristome is formed by two thick cal- careous plates, distally separated and projecting straight outwards, which have a fairly strongly arched outer surface and reach almost to the proximal third of the ajierture.
The operculum, which is extremely thick and of a brownish yellow colour, is strongly arched in the greater part of its inner surface while the outer surface has a corresponding concavity. The inner arched part which shows two small muscular dots and evenly grades into a lower marginal portion ends proximally in a narrow, tongue-shaped part, inserted in between the two hinge-teeth. Each zocrcium is separated from the adjacent zoa'cia by four long, narrow separating walls and from one of the ahove-mentioned„small, enclosed avicularian chambers by a small, innermost wall. Each of the four separating walls is provided within each lateral margin with a row of up to 8 small, uniporous rosette-plates.
The avicularia, appear in two ditl'erent forms, those placed on the zoa^cia and those occupying partly the flat base and partly a great inner portion of the conical colony. The latter we may call the basal avicularia. The former which occur in similar numl)ers to the zoa>cia and the frontal area of which has a similar length as the zooecial aperture, are provided with a broad, triangular mandible with its point directed as a rule obliquely distally towards the higher- placed zooecial aperture in a neighbouring row and obliquely out from the surface of the colony. The strong transverse bar between the opercular and the suboper-
312
cular areas is provided as a rule with three rods directed towards the apex of tlie aviculariuni, of which the middlemost is Ihc longest. Some few j)ores are seen on the surface of the aviculariuni. The hasal avicularia which as growth proceeds are inclosed in the interior of the colony have a very small, sometimes almost circular, sometimes short egg-shaped frontal area the cross-bar of which is jirovided with a single rod. The mandible is almost semicircular. The avicularian chambers, the length of which is not very different from the height of the zotccia, are elongated vertically and the single chambers are in inner connection by means of a few single-pored rosette-plates. Each free wall is furnished with 5 — 8 pores surrounding the avicularian area.
The lunoecia occur in very small number and for each zod'cial row (here is scarcely a single luncecium. They may occur both in the zoo'cial and in the avicularian rows, and there are usually proxinially to each of them two, as a rule very small avicularia, the mandible of which is diiectod oblicjuely proxinially (towards the broad end of the colony) and outwards. More rarely there is only a single one which has the mandible directed proxinially.
The colonies are top-sliaped and both the zocrcia and the avicularia are ar- ranged in radiating, more or less regular rows. Further, there is an arrangement into one or partly two systems of obli(|ue rows rising obli(juely towards the tip, and the single rows are here accentuated by step-liUe depressions.
Colonies from Port Jackson and Port Stephens, Australia.
To the genus Flahellipora lielong several species in the (>openliageii Zoological Museum and one of them is [)robably identical with d'Orbigny's Fl. elccjans, but not with Waters' species of the same name. A colony from Port Jackson, which has quite the same fan-shaped appearance as Waters' species, probably belongs to this, for which I would propose the specific name ftabellaris. Like the species of the genus ConescbaveUimt it is provided with luncccia, but the zooecia are as in Flahellipora arranged in two layers. For this form the \acanl generic name Blpova might be employed, but this can only be retained willi the reservation, that the main dilTerence between Conescharellina and Bipora, as this genus is understood here, appears to be constant; it is just the presence in the former genus of the al)ove-mentioned, enclosed, small avicularia. The following statement of Waters' would indicate however thai such avicularia may occur in the spe- cies mentioned; >others have between the layers a cancellous structure with num- erous large openings, between which are small round avicularia*. In this case
' 107, p. 200.
313
the present s[)ecies and others nearly related must then be included under the
genus Conescharellina.
Family Liriozoidae.
Epicaiilidiidae Hincks*.
The slender, elongated zowcia, which may have a single spine at the distal end, are provided as a rule with scattered pores and the lateral walls with one or several uniporous roselte-plates. The apertui'e has a broad and low sinus and a weakly chitinized operculum. Avicularia and oa'cia are wanting. Free, jointed colonies, with the zocrcia arranged in pairs or in triads; in (he latter case they arise from an axis consisting of kenoooecia.
Genera.
The colony consists of an axis ol' kenozooecia, each of which bears two opposite triads of zoa-cia. Of the 3 zooecia, the longest, central one has the aperture directed outwards, whilst the two outer, which have a distal spine, have theirs directed obliquely inwards. . . . Liriozoa Lamarck.
' (Epicanlidium Hincks.)
The colony consists of paired zoa>cia, and in each pair the slightly spirally turned zoa^cia have their basal sides directed towards each other; no spines Gemellipora Smitt -, char, emend.
To the first genus belongs L. tiilipifera P^llis & Sol (= E. piilchruin Hincks), and to the latter, which we here take in a more restricted sense than Smitt, belongs G. elniriiea Smitl.
Family Lekythoporidae n. f.
(PI. XVI, figs. 6:1— Gc, fig. 7n).
The zowcia, which have no sjjines, are solidly calcified, thick-walled and provided with a wcU-chitinized operculum. A strongly develoj)ed, sometimes im- mersed, sometimes freely i)rojecting, tube-shaped peristome, the aperture of which is armed with one or usually with several (2 — 5) small avicularia. Scattered small or large avicularia may also occur. Both the distal wall and the lateral walls are provided with numerous small, scattered, uniporous rosette-j)lates, which are situated at the bottom of shorter or longer canals. The owcia have the form of a hemispherical expansion of the frontal wall of the peristomial tube and be- come later hidden by covering calcareous layers. The colonies are free, more or less strongly branched.
To this famih', which no doubt is most nearly related to the Celleporidae, I must refer Le/v-;///ioy)ora /i(/.s7r(x Mac Gill. ^ Tiirritigera stellata Busk^, >Sc/i(:o/3ore//rt«
' 24, p. 156; 2,-), p. 135. ^ 103, p. 35. ' 66, p. 194; 68, p. 113. * 8, p. 130.
314
r/ia//c/iyer/« Waters' (== Miiriozoiiin imniersnm Busk) and Oiihojwra cnmpdcfn'Wuiprs''. To the last author is due the demonstration of the peculiar oa^cia in T. stellata and »S. chdllengeria. I have been able to examine small fragments of the first three species, but my material has not been sufficient to settle the (jueslion, whether they should be referred to one or to several genera.
Family Eurystomellidae n. f.
No s[)ines. The thick-walled and strongly calcified zooccia lack a covering membrane and have either no pores at all or 2 — 5 extremely large fenestrse. The broad aperture, which has a concave proximal rim, is |)rovided with a more or less strongly chitinized operculum surrounded by a continuous marginal thick- ening. No aviciilaria. The ofvcium is enclosed in a kenozooecium, the frontal wall of which is provided with a very large uncalcified |)art. Pore-chambers or groups of uniporous rosette-plates.
To this family I refer Lepralict' foramin'mera Hincks' (PI. XVIII, figs. 14 a— 14 c) and "Lepralia' bilabiatu Hincks ', and I regard them provisionally as belonging to the same genus Kunjstouwlla. There may possibly be reason however to form a special genus for L. bilabiata. In this species the distal wall and the distal half of each lateral wall are provided with a group of numerous small, uniporous rosette-plates, whereas multiporous pore-chambers occur in L. foraiiiininera.
Family Escharellidae n. f.
The zowcia, which are often armed with (2—8) spines, have as a rule a dis- tinct vestibular arch, in many cases even strongly developed. If (wiciilaria occur, they are as a rule lateral and there is never a median, symmetrically placed avicularium. Pore-chambers usually present, more rarely uni- or multiporous ro- sette-plates. The o(vcia which are as a rule hyperstomial, very seldom endoooccial consist of a membranous, more rarely partially calcified ectooa-cium and of a calcified endoocecium, which usually shows no pores and more rarely has small scattered pores.
Whilst I have found a covering membrane in the genera Escharella, Escharo- ides, Schizoporella, Escharina and Cijclicupora, I have been unable to find this in Anarthropora, Exochclla and Arthropoma, of which genera I have examined colonies preserved in spirit. Though I am inclined to attach no little weight to this character, I have for several reasons not ventured lo make this negative result decisive as to whether I should refer the genera mentioned lo this family. In the first i)lace,
' no, p. .so. ^ 115, p. 75. ' 28, p. 1U9. * U, p. 49.
315
the covering membrane in many forms is extremely thin and very readily torn, and the absence of il in one or two colonies is no sure evidence, that it is lacking in the species examined. Secondly I have become somewhat doubtfull as to the systematic significance of this character, as in the genus Microporella some species, for instance M. ciliala, possess a covering membrane while it seems to be lacking in others. Thus I have not been able to find it in a fresh colony from Norway in which the young zooecia in the growing margin show the membranous frontal wall well-preserved, and the same is the case with a nearly related species from Japan, appearing in two-layered, /''/(/.s/m-like, richly branched tufts.
Escharella' Gray, char, emend. Mucronella Hincks |). \^. Lepralia Hincks p. p.
The zod'cia, which usually have 2 — 8 spines, are provided with a well-devel- ojjed, .sometimes even strongly developed vestibular arch and usually with a more or less developed often mucronale peristome, which rarely embraces the distal margin of the aperture. The operculum is mostly thin, almost membranous, some- times more or less strongly chitinized and in the first case the proximal margin of the aperture is generally protected by a median tooth. No (wicalaria. The oaria, which in some species are endozorecial and covered by kcnozoa?cia, have no pores. Marginal [)ores appear as a rule, rarely scattered pores. In the distal half of the zoa'cium there are numerous small (12—18), uniporous, contiguous pore-chambers, which have arisen by division of three elongated, multiporous chambers (a distal and two lateral).
To this genus belong the following species: E. iinmersa, Flem. (^ Miicroiiclld Peachii, Johnst. + '^^- ventricosa, Ha.ssall), E. (Miic) variolosa, Johnst., E. abiissi- cola, Norman (= E. laqiieata, Norm.), E. (Mm:) microstoma, Norman, E. emmro- mita, Smitt-, E.stemisloma, Smitt-, E. (Mm:) spimisissima^, Hincks, E. (Lepralia) polila, Norman, E. (Lepralia) multispimita, Busk^ and E. (Mm:) dia})liami, Mac Gillivr.
The vestibular arch, which in this genus varies greatly in form and extent, reaches its greatest development in E. diaphana and E. microstoma, in which two species it reaches far into the zoa-cium in the form of a pent-roof. A median tooth is lacking in E. microstoma and E. polita, and the two last possess a strongly chitinized operculum with a convex, proximal margin. The oa'cia are surrounded by kenozooecia in li. diaphana, E. (dnjssicola, E. polita and also, so far as I can determine on a small colony with a single, broken ooccium, in E. microstoma.
' 84, p. 116. ^ 101, p. 1129—30. ' 28, p. 53. ' 8, p. 160.
316
Escharella diaphana Mac Gillivr.
Leprnlia diaphana Mac Gillivr., Mac Coy, Prodroinus of tlic Zoology of Victoria,
Vol. I, Decade IV, p. 22, PI. 35, Tig. 3.
(PI. XVII, lifi.s. l:i-i ti).
The zooecia, which usually have a rounded rhombic form, arc rather strongly arched, Ihin-walled, smooth and surrounded by raised lines, which end on each side at the inner part of the frontal spine. M'hile these raised lines (formed by the free continuation of the lateral walls) in the proximal half of the zoa^cium are very low and separated from the arched frontal wall by a groove, in which a number of marginal pores can be more or less distinctly seen, they are very high in the distal half (provided with the pore-chambers), and here they lie close up to the lateral pari of the frontal wall wilh which they partly coalesce, in such a manner that each marginal pore opens out on the frontal wall through a canal, which can only be seen in side view. The almost circular aperture is sur- rounded by (5 articulated spines and provided with a small median tooth, broader towards the tip and twice or sometimes three times cleft. The well-developed ascending and generally mucronate peristome is in most cases marked olT from the rest of the frontal wall by a distinct line which meets the niarginal furrow, and the vestibular arch (figs. 1 c, 1 d) is continued deep into the zooccium as a strongly arched lamina, wilh the convexity towards the basal wall of the zoce- cium and its concavity towards the aperture, through which it can readily be seen in zooecia boiled in caustic potash solution. Each of the lateral parts of this lamina is connected with the corresjjonding lateral wall of the zoa'cium by a calcareous, cylindrical rod growing out from the latter. Each zocecium is in its distal half provided with 16 — 20 closely-placed, uniporous pore-chambers forming a strongly projecting basal pari, and similar pore-chambers occur in the circum- ference of the kenozocccia covering the ooecia.
The ooecia are endozoa-cial and the strongly arched, smooth frontal wall of the covering kenozoircia sometimes shows faint, radiating stria'.
The colonies form crusts on alga', and on one of Iheni was found a primary zocecium (tig. 1 a), the aperture of which was surrounded by 12 spines. The vestibular arch was in this less developed and seemed to lack the two cal- careous rods.
Australia (The Botanical Museum of Copenhagen).
317
Anarthropora (part) Smitt. The zoa'cia, which have no spines and are provided with scattered stellate pores, have a well-developed vestihular arch. The primary aperture has a'straight proximal margin and a meml)ranous or very slightly chitinized operculum, which is not separated from the compensalion-sac. A short tuhe-shaped peristome, which nniy have a small distal and a small proximal auiculariiim. No on-cia. Closely- placed uniporous pore-chamhers. In this genus there is only a single species, A. monodon Busk.
Inversiula Jullien'. Microporella Hincks.
The zoa'cid, which have no spines and are provided with scattered stellate [)ores, have a distinct vestibular arch. A simple, strongly chitinized operculum occurs, attached at its distal, straight margin. No peristome. A round ascopore. Two small, lateral ainciilaria proximally to the aperture. No oacia. Densely-placed uniporous pore-chamhers.
To this genus belong /. iiwersa Waters and /. niitrix Jullien.
The last two genera stand very close to each other and in addition to the common characters mentioned in the diagnoses, some agreements in the structure of the frontal wall may also be pointed out. We thus find a system of winding canals, which open outwards through a circle of marginal pores, and in younger zooecia the wall is distinctly composed of a mosaic of radiate, striated small plates, each of which has a stellate pore in the centre.
Escharoides' Milne Edw. Peristomella Lev. ^; Mucronella Hincks p. p. Romancheina Jullien^ p. p.
The primary aperture, which may have up to 6 spines, is provided with a strongly developed vestibular arch, which has as a rule a thickened free margin. There is a strongly developed, often mucronate peristome, which may sometimes have an inner median tooth and is not separated from the primary aperture by any distinct boundary. The operculum is as a rule membranous, very rarely strongly chitinized and then forked at the tip. An aviciihiriiim may appear on each side, but is often wanting on one or the other side or even both on more or fewer zoiL-cia. The oacia, which are not found in all species however, have a
' 4.5, p. 44. - 84, p. lUi. ' .-)(!, p. 2(1. ' 45, p. (SO.
318
membranous ectooa'cium, and the endoooecium may be provided with a number of very small scattered pores. Multiporous rosette-plates or nuiltiporous pore- chambers occur as a rule, very seldom uniporous pore-chambers.
To this genus I must refer the following species: E. (Romancheina) Martiali, Jull.', £. (Mucronella) cocc/nea, Abildg., E. (?Sniittia) ./ficAso/n', Waters^, E. (Mucr.) praestaiis, Hincks, E. (Mucr.) contovla. Busk, E. sduroylossa n. sp., E. (Porina) larvalis, Mac Gill.' and E. (Mucronella) labiata, Boeck*, the last species having no avicularia. Of the species mentioned E. Martiali is provided with uniporous pore-chambers.
Escharoides praestans Hincks.
Mucronella praestans Hincks, Annals Nat. Hist., ser. 5, Vol. X, 1882, p. 1(J8,
PI. VII, fig. 1. (PL XVII, figs. 4 a-b).
The zooecia hexagonal, ascending strongly both from the proximal end and from the sides towards the strongly projecting, spout-shaped peristome, which has no median tooth and often projects so freely, that regarding the zooecia from the frontal aspect we can only see the distal half of the four spines. The zooecia, the slightly luberculated surface of which is marked with fine, radiating stria;, are provided at the margin with one or more circles of round pores separated by rib-shaped projections. Each lateral wall has 3 — 6 connections with neighbouring zooecia, and these are represented sometimes by multiporous pore- chambers, sometimes by multiporous rosette-plates. On each distal wall there are either three pore-cbambers or two with an intermediate rosette-plate, and one of the two adjacent half lateral walls is likewise provided with 2 — 3 pore-chambers, one of which however is also connected with the distal wall.
Goecia are wanting on the colony investigated, but are described and figured by Hincks, from whose account it appears, that they must be i)rovidcd wilh an ocecial cover, as otherwise they would not have pore-canals.
The avicularia, which are lacking on numerous zocecia, appear only singly towards the one lateral margin and are of a considerable size. The strongly prominent chamber provided with some scattered pores has a well-developed cryptocyst and the lyre-shaped mandible tends obliquely outwards and proxi- mal ly.
Found on a Mollusc shell from Stewart Island, New Zealand (Zoological Mu- seum, Cambridge, Engl.).
» 45, p. 60. = 114, p. 87. ' 107, p. 18<l. * lOll, p. 21.
319
Escharoides sauroglossa n. sp. ? Smittia praestans Waters, Annals Nat. Hist. ser. 6, Vol. IV, 1889, p. 17,
PI. Ill, figs. 9-11. (PI. XVII, figs. 6a-0.
Seen from the basal aspect the contour of the zooecia is more or less regul- arly hexangular, and the evenly arched frontal surface, somewhat ascending to- wards the distal end, is provided with numerous, large, scattered pores, which are in part the outer openings of pore-canals, The peristome is medially provided with a fairly broad and deep, rounded sinus, and just behind or within the centre of this projects an elongated but strong tooth, which narrows from a broad base outwards. There is internally on each side of the sinus a strong, triangular, lateral tooth. The well-developed distal arch, the central part of which is somewhat prominent, has, a finely tuberculated, somewhat thickened margin. The strongly chitinized operculum has a very characteristic form. It is longer than broad, and its broader proximal part, which is provided with a concave margin, runs out on each side into a short, hook-like projection. The two somewhat bent and dis- tally converging lateral walls pass over in the distal half of the operculum into a narrow, recurved marginal part. The operculum is provided at the tip with a deep, rounded incision, and it thus comes to end in two, sometimes equally large, sometimes unequally large points. This operculum takes up such a position, that its forked end reaches over to the distal margin of the aperture, whilst the proxi- mal part, which is connected with the compensation-sac, arises at a fairly long distance proximally to the median tooth. Each half of the distal lateral walls is provided with 2 — ;5 multiporous rosette-plates and each distal wall with 2 multi- porous pore-chambers and 1 — 2 interjacent rosette-plates.
Ooecia are wanting on the colonies investigated.
The avicularia, which vary greatly in size, occur in pairs, and the two be- longing to the same zooecium may sometimes be of the same, sometimes of very dilferent size. The freely prominent avicularian chamber, which is provided with scattered pores, has a strongly developed cryptocyst and the mandible is obliquely lyre-shaped in the larger, obliquely oval in the smaller avicularia.
Two small, free, one-layered colonies are to hand from 33"?' N., 129" 20' E. and 33" 8' N., 129" 20' E.; depth 36—40 fm. (Schonau).
In a small colony from Port Phillip, Victoria (Miss Jelly), the aperture has no sinus nor lateral teeth, and there is usually only a single avicularium. The operculum has almost even lateral margins and is only slightly indented at the point.
320
Exochella Jullicn', char, emend. The primary aperture, which is provided with 2—5 jointed spines, is separ- ated by a distinct boundary from the peristome and furnished with a distinct, but not strongly developed vestibular arch. The operculum is slightly chitinized and not distinctly marked off from the compensation-sac. The peristome has three, sometimes coalesced teeth, a median and two lateral, which may appear again with greater or less distinctness in a secondary peristome. Normally there is an (wiculariiim on each side, but in more or fewer zod'cia the one or both may be absent. There is apparently a membranous ectooa?cium and in the distal half of the zoa-cium there are 3 large, multiporous pore-chaml)ers.
Exochella triccuspis Hincks. Mucronella tricuspis Hincks, Annals Nat. Hist. ser. 5, Vol. VIII, 1881, p. 125, PI. Ill, fig. 1. (PI. XVII, figs. 9 a— d).
The zooecia, broadly rhomlnc, evenly arched, often with more or fewer, larger or smaller tubercles of varying form. A raised marginal line is as a rule indis- tinct and the marginal pores in part difficult to observe. The primary aperture, which has three spines, has a broad and low sinus (fig. 9 b) more or less sharply marked off from the lateral margins; in the full-grown zoa^cia it can be distinctly seen through the frontal wall (fig. 9 a). The operculum (lig. 9 d) does not have distinct muscular ridges. There is a well-developed, tube-shaped peristome, which conceals the spines and the distal half springs from the frontal wall of the dis- tal zooccium or in the ooccium-bearing zooecia from the proximal part of the ocEcium.
The peristome is provided with three coalesced teeth, the central one widened at the end, hammer-shaped, and connected at the widened end with the two short, finger-shaped lateral teeth. Outside there is a new set of uncoalesced teeth, the central one not widened whilst the two lateral are strongly truncate, rounded projections.
The ooecia are furnished with finely, radiating striae and enclose the s])ines.
The avicularia, the narrow elongated mandible of which points outwards, appear as a rule in pairs, sometimes almost at the same, sometimes at somewhat different levels.
Two small fragments from Victoria are to hand (iMiss .Jelly).
' 45, p. 5o.
321
Exochella longirostris Jullien.
Mission scientifique du Cap Horn, 1882 — 83, VI, Zoologie, 1888, Bryozoaires,
p. 55, PI. 3. figs. 1—4, PI. 9, fig. 2.
(PL XVII, figs. 6a-b).
The zocecia elongated rhombic, evenly arched, provided with radiating striae and rather densely covered with finer or larger tubercles. There is a distinct raised mar- ginal line, and the very distinct marginal pores, of which there may be up to 10 on each side, lie in older zooecia in deep pits separated by projecting ribs. The primary aperture, from the distal margin of which project up to 5 spines, has no sinus, but runs out into a low, quadrangular median tooth, which in younger zooecia can be seen distinctly through the frontal surface.
The well-develoi)ed, tube-shaped peristome, the distal part of which has a similar origin as in E. trisciispis, is provided with a median tooth, frequently somewhat widened at the end and often with two or three cusps, and two finger- shaped lateral teeth, wiiich as a rule do not reach the median tooth and at most touch this. Outside there is a new set, consisting of an unwidened median tooth and two bluntly rounded lateral teeth. The operculum has a faint muscular ridge at each of the proximal corners.
The ooecia are furnished with fine radiating striae and enclose the spines.
The avicularia which sometimes are single, sometimes double, have a similar position and structure as in the previous species,
A small colony from the Challenger St. 315.
Exochella lobata n. sp. (PI. XVII, tigs. 7 a— c).
The zooecia hexagonal in circumference, strongly arched, often provided with a number of large, scattered tubercles and in the younger zoa'cia with ca. 5 large marginal pores. The raised marginal lines are only feebly developed. There are four spines, the two central being much thinner than the two outer thick ones, which are not covered by the oo-cium. Within each lateral margin the faintly chitinized operculum is provided with a muscular ridge (fig. 7 c).
The peristome, which is only developed proximally, runs out into a large, Ihick, Inoad, triangularly rounded rostrum, within which there are two sets of teeth. Of the teeth in the inner set, which are placed rather closely together and divided by two rounded gaps, the central are as a rule hatchet-like, whilst each of the lateral teeth have the form almost ot half the blade of an axe. The teeth outside these have a somewhat similar form, but are much more elongated and
21
322
in most zoa'cia they are further more or less nodulous or lobate or even more or less deeply divided.
The ooecia, which are strongly arched and not rarely provided with one or several tubercle-like projections, show as a rule a narrow depressed margin im- mediately distally to tlie aperture, caused apparently by the thickening layers not reaching quite so far down.
The avicularia, which are placed nearer to the aperture than in the two species above described and in which the mandible points obliquely distally and outwards, appear sometimes double sometimes singly.
A small colony from Port Western, Victoria (Dr. Harmer).
Exochella Zelanica n. sp.
Mucronella diaphana, forma armala Hincks, Annals Nat. Hist. ser. 5, Vol. X, p. 167, PI. VIII, fig. 3. (PI. XVII, figs. 8a-e).
The zooecia hexagonal, rhombic, thick, rather strongly arched, provided with small scattered pores and with 3 — 4 oral spines. They are surrounded by a strongly developed raised line which in the same manner as in EschareUa dia- phana may be partly coalesced with the lateral parts of the frontal wall and often has a freely projecting undulating edge (fig. 8 c). There are 6—7 marginal pores.
The peristome is only developed proximally and of the two sets of teeth the inner has a somewhat similar form as in the foregoing species, whilst the strongly projecting and prominent, central tooth of the outer set is large and broad, quadrangular or trapeziform, coalesced along its frontal surface with a somewhat narrower thickening of similar form.
The ooecia, which were not found on the colony examined, are according to Hincks provided with a thickened middle part.
The avicularia may occur both in pairs and singly, but their position and direction seem to undergo more variation than in the previous species.
I have seen a very small colony of this species, found on an Alga from the Akaroa Harbour, New Zealand; depth 6 fathoms.
Genus Schizoporella Hincks, char, emend.
Spines may appear. The aperture with a faintly developed vestibular arch and with a well-developed sinus, which may vary greatly both in depth and breadth. The operculum well-chitinized, with muscular dots. The zoa'cia with scattered pores and as a rule with a small projection proximally to the aperture. An ai>i- culariiim may occur on each side, but in more or fewer zoa»cia the one or both
323
may be absent. The oaria consist of a calcified endoooecium and a membranous ectooa'ciuni. Uni- or multiporous rosette-plates, which may sometimes be placed in pore-chambers.
Both the form of the sinus of the aperture and the rosette-plates undergo consideral)le variation in the species I have hitherto been able to refer to the genus Schizoporella as defined here. Thus, whilst the sinus is extremely narrow in S. spongites and S. Ion()irostris, that in .S. unicornis is broadly rounded and has more than a third of the whole breadth of the aperture. We have an inter- mediate form in regard to the development of this sinus in S. xanguinea, and for the rest local forms e. g. of S. spongites show how much this sinus varies. Simil- arly the rosette-plates undergo a considerable variation, as they are sometimes uniporous, sometimes multiporous or the two together and at the same time as the number of pores in the single rosette-plates increases, the number of the rosette-plates themselves decreases. In S. unicornis 2 — 3 rosette-plates with up to ca. 19 pores in each occur on the distal half of each lateral wall.
In addition to two new forms not described in this work I refer to this genus the following species: >S". unicornis Johnst., S. longirostris Hincks, .S. spongites (Pallas) Smitt, S. sanguined Norman, .S. errata Waters and S. luaperta Michelin.
Schizoporella longirostris Hincks.
Schizoporella unicornis, form longirostris Hincks, Annals Nat. Hist. ser. 5,
Vol. XVII, 1886, p. 266, PI. X, fig. 2. (PI. XVIII, ligs. 3 a— g).
The zocecia rhombic or trapeziform, strongly arched, with fairly small, densely placed pores, each situated in a deep pit. Proximally to the aperture (here is usually a larger or smaller, often strongly projecting tubercle. The aperture, which apart from the sinus is almost ([uadrangularly oval, is provided with a very faint distal arch, which on each side passes over into a long, high, curved hinge-tooth. The deep and narrow sinus decreases evenly in breadth towards the end. The peristome is represented [)arlly by a low wall, which may surround a larger or smaller part of the aperture and sometimes bears indistinct marks of 3 — 4 spines, partly by two small prominent, triangularly rounded projections, which partially cover. the primary sinus and form a secondary sinus; sometimes they almost meet. The strongly chitinized, thick, yellow operculum, which on each side of the accessory portion shows a mark from a hinge-tooth, is proxi- mally provided with a small, rounded, thin expansion. The distal half of the zo(rcium is provided with numerous small rosette-plates, which are placed very close together and each of them is enclosed in a small pore-chamber with thick
21*
324
walls. Each rosette-plate has 1 — 5 pores and the largest number of rosette-plates, ca. 13, are found on the long wall (see fig. 3 a), along which the avicuiarium is situated. The pore-chambers here are also provided with the the thickest walls.
The ooecia are very strongly arched and provided with a strongly projecting central part. The numerous pores are immersed in pits, which are separated by a net-work of ridges and ribs.
The avicularia occur on most of the zod'cia in the colony examined, in which the primary zooecium and a number of the oldest zott>cia are distinct. On some of them a very small avicuiarium with triangular mandible is found on the one side of the aperture, but however thej' seem to increase gradually in size in the zofficia which appear later, at least to a certain extent, and they are in general provided with a long, narrow, pointed mandible. The more or less strongly arched chamber, which is provided with scattered pores, shows a somewhat different appearance in the basal j)art of the colony from in the part produced by superficial budding. Whilst namely the avicularia in the latter part of the colony are very prominent and show the mandible pointing in all possible di- rections, thej' are in the former part partially immersed in the zoo'cia and situ- ated along the one lateral wall of these with the mandible pointing outwards and obliquely distally.
A single small colony of this species was found on a Mollusc shell at Syra- cuse by Dr. H. J. Hansen; de]ith 12 — 25 I'm. I have later obtained colonies of this species from Oran (Algiers), which in addition to small difTerences in the form of the aperture and operculum also show a slight dilTerence in the structure of the rosette-plates, the number of pores lying between 3 and S.
Schizoporella spongites (Pallas) Smitt.
Hippothoa spongites Smitt, Kgl. Svenska Vetensk. Akad. Handl. 11 B., No. 4,
1873, p. 42, PI. VIII, figs. 161 — 163.
(PL XVIII, figs. 4a-d).
The zooecia are rectangular, weakly arched, with numerous, scattered, fairly
large pores, between which there are larger or smaller tubercles. Frequently
there is a tubercle-shaped projection proximally to the aperture. The anter of
the aperture is broad, almost semicircular or semielliptical with lateral margins
converging somewhat proximallj', and its poster is on each side provided wilh a
long, low hinge-tooth. The narrow sinus, somewhat contracted at its origin, is
rounded at the end, and at its beginning there is as a rule a small, conical j)ro-
jection on each side, which is directed inwards. The operculum, the accessory
part of which gradually becomes very narrow from the broad distal part, ends
325
in a less strongly chilinized, disc-like part, which fits into the bottom of the sinus. Distally to this the accessory part is on each side provided with a longi- tudinal thickening. Each distal wall is provided within its basal margin with ca. 10 and each lateral wall in its distal hall' with ca. 5 uniporous rosette- plates.
The ooecia are of enormous size, equalling the smaller zooecia in length with at the same time a breadth up to one and a half times that of the zooecia. They are almost spherical and their very thick wall is mainly composed of a tuber- culated net-work of ribs, with numerous scattered pores at the bottom of the meshes. They quite cover the distal half of the zooecium to which they belong (as well as the proximal half of the distal zooecium), and this is only seen on removal of the frontal wall of the ooecium. Such an ooecium must therefore during its formation send down a part on each side outside the respective avi- cularium, and these two parts meet proximal ly to the zooecial aperture. The semicircular ocecial opening which cannot be seen from the frontal surface, is partially closed by two finger-shaped prolongations almost meeting at the tips, which spring from the two corners of the opening. There can here be no doubt that the eggs must pass directly from the zooecial aperture into the ooecium (see pag. 67).
The avicularia appear in two different forms, the one of which has an elong- ated triangular, the other a lyre-shaped mandible. The former, which are of some- what small size, appear on the single zooecia to a number of 1 — 5 and usually on each side of the aperture, with the mandible directed obliquely outwards and distally. On the others the mandible may point in different directions. The avi- cularia with lyre-shaped mandible, which occur in much smaller numbers, are considerably larger, but vary however a good deal in size, hi the basal part of the colony, where they are equal in size to the zooecia, they always take the place of the zoa'cia.
The species occurs as incrusting colonies, which have superficial budding.
West hidies, St. Thomas and St. John, l.*! — 20 fathoms.
A colony from Aor, Malacca, shows several differences from that just described. Thus, the zooecia have as a rule only a single avicularium on the one side of the aperture and the accessory part of the operculum has a similar form to that in S. longirostris, but lacks the small border at the tip.
;{26
Escharina ' Gray, char, emend. Sfhizoporella Hincks p. p., Masligophora Hincks p. p.
The zoivcia, the aperture of which is as a rule provided with 3 — 8 spines, have a more or less well-developed vestibular arch, and the primary aperture has a sharply marked olT, fairly deej) sinus, (he breadth of which is at least one- third of the breadth of the whole aperture. On each side of this the i)ro.\imal rim of the aperture is j)rovided with a long, narrow, often crenulated or finely denticulate hinge-tooth and the somewhat slightly chitinized operculum is pro- vided with a muscular ridge within each lateral margin. Proximally to the aper- ture there is as a rule a small, tubercle-like projection. A helerozoa'cium, which is sometimes developed as a inhraciihiin and sometimes as an ainctilariiiin, may occur on one or both sides, but is not rarely lacking on more or fewer of the zooecia. The oa-cia, which in rare cases seem to be endoooecial, consist of a cal- cified endoooecium without pores and of a membranous ectoooecium. The distal half of the zooecium is piovided either with three long, multiporous pore-cham- bers or with a larger number of single- or few-pored chambers placed close together.
To this genus belong the following species: S. (Schizoporella) spinifera Johnst.,
■S. (Schiz.) inih/aris Moll., E. (Schiz.) Alderi Busk. E. (Schiz.) simplex Johnst., E.
(Masti(jophor(i) Diitertrei Aud., E. (Mast.) Hiindmanni Johnst. and E. (Mast.) i>es
anseris Smitl. Possibly Schiz. loiKji.spiiiala Busk and Schiz. dncdala Mac Gill, should
also be referred here.
Escharina pes anseris Smitl.
Hippothoa pes anseris Smitt, Kgl. Svenska Vetensk. Akad. Handl., 1873, \^^\. 11,
No. 4, p. 43, PI. VII, figs. 159—160.
(1^1. XVIII, figs. 1 a-c).
The zooecia broad, pentagonal or hexagonal, evenly arched, with numerous, small, densely placed pores, from the margin of which a nund)er of fine points or rods radiate and these sometimes seem to form a connected network in I he lumen of the pore. The pores may presumably become closed in lime by this network, and according to Smitt's description the wall is without pores. The aperture is provided with a somewhat slightly arched distal margin, and the lateral margins which converge somewhat proximally form on each side a small, angularly pointed corner with the corresponding convex half of the proximal
' 84, p. 109.
327
margin, so that the sinus which is rounded at its bottom and narrowed at its be- ginning is bounded by a rounded trapeziform j)rojection, which along its distal margin has a finely serrated hinge-tooth. The operculum, which is well-chitinized and provided with an extremely short and weak muscular ridge within each lateral margin, has two proximal, angularly pointed corners and a proximal, rod- shaped prolongation, which however is somewhat narrower than the sinus. The aperture is surrounded by a low, wall-like peristome, the proximal half of which is very flat. In the ooecium-bearing zocecia the peristome is continued as a fairly high and as a rule Hat belt down over the proximal part of the ooecium. There is a well-developed vestibular arch and 6 — 7 spines, which on the ordinary zoce- cia form a connected arch, whilst on the ooecium-bearing zooecia three are placed on each side proximally to the ooecium. On an extremely small colony, the place of origin of which is unknown, a somewhat large, projecting tubercle with a (lat surface towards the aperture is found immediately proximally to the sinus of the aperture in most of the ooecium-bearing zooecia, but in the single zooecium of the colony without an ooecium there is instead a broad, arched ridge-like pro- jection. This zott'cium is possibly not quite normal, as the form of the aperture seems also somewhat different. In the distal half of the zooecium there are ca. 10 small pore-chambers.
The ooecia seem to be endozooecial, the basal half arising within the distal, frontal wall of the zooecium, whereas their frontal half appears distinctly on the surface of the zooecium. They are fairly small and low, without pores and are present on most of the zooecia of the colony.
Heterozooecia. On each side of the aperture there is a large, somewhat pro- jecting, oval heterozooccium, which may be regarded as a vibraculum ; but the flagellum has an unusual form as it consists of a short, thick, rod part and a lamina running out into three pointed lobes. For the reception of the thick rod part the distal part of the chamber has a broad and deep incision, and the cal- cified transverse bar is plate-like, compressed and widened in a greater or smaller part of the length. It may also be noted that the basal surface of the chamber is continuous with that of the zooecium, for which reason the vibraculum like the pore-chamber can be seen through the basal surface of the zooecium, and the same applies to the vibracula in E. vulgaris, and partly also to those in E. Hijnd- manni. Of this species our Museum originally possessed only a small colony with- out indication of locality and the figures on PI. XVIII were drawn from this. Later I have been able to supplement my description from the examination of several small colonies from Siam (Koh Kram; 30 fathoms) taken by Dr. Th. Mortensen.
328
Microporella Hincks, char, emend. Diporula Hiiicks, Fcnestriilina JuUien.
The zou'cia, which may have up to 7 spines, possess a vestibular arch, devel- oped to a varying extent, and a semicircular aperture provided with a straight or very slightly concave proximal rim. In most species there is within this and in the whole of its breadth a higher or lower supporting beam as support and attachment for the operculum. The latter is simple, more or less chitinized and provided with a muscular process within each lateral margin. A peristome is wanting or only weakly developed. One or two lateral heterozooecia are present and a median ascopore, proximally to which there may often appear a tubercular projection. Multiporous pore-chambers occur as a rule and the ocecia consist of a calcified endoorecium, which as a rule has no pores, and a membranous or partially calcified ectoooecium.
The two genera Escharina and Microporella show such great agreement in their structure, that there can scarcely be any doubt that the former must be regarded as the mother-genus to the latter, and the greater or smaller resemblance which various Escharina species show to corresponding Microporella species, would seem to indicate that the transformation of an Escharina species to a Microporella species has occurred several times. Apart from the variation occurring in both species, the resemblance between Escharina spinifera and Microporella ciliata is so great, that we might well consider that the latter has descended directly from the former. The two species thus agree in the number of oral spines, in the i)osses- sion of scattered pores, an avicularium and of three elongated pore-chambers. In both species there may be a tubercle-like projection proximally respectively to the ascopore and the sinus, and the former quite agrees in form with the prox- imal part of the sinus. Further, the ocEcia agree, and the supporting beam in Mic. ciliata might be considered as having arisen by a fusion of the two long hinge-teeth in E. spinifera. The supporting beam mentioned is for the rest weakly developed in Mic. ciliata (PI. XV, fig. 5 b), whilst it reaches its greatest develop- ment in Mic. marfjinata (PI. XV, fig. 3 b). It seems to be quite wanting in Mic. Malusi (Pi. XV, fig. 7 a). Two other species which also show essential agreement are Escharina pes anseris and Microporella /lahellidera n. sp., but the difierences between them are too great to permit us to conclude that the latter has come directly from the former. They agree amongst other characters in possessing vibra- cula and endozooccial ocecia, and in both there may be a tubercle-like project- ion, which has its flat surface directed towards the aperture. Whilst in this genus there is as a rule a membranous ectoooecium, the arched calcified ridge which
329
surrounds the oa?cium in Mic. Malusi arises from a calcification ol' the marginal part of the ectoooecium and in Mic. decorata the distal half of the ectoooecium is calcified. The distal half of the endoooecium is provided with scattered pores in Mic. decorata (PI. XV, figs. 6 a— -6 c) and sometimes also in Mic. ciliata. If the lack of a covering membrane in Mic. Malusi and allied species is corroborated by later examination, these species which also lack avicularia ought to be referred to a special genus for which the name Fenestruliiia JuUien must be employed.
Microporella marginata Krauss. Flustramorpha marginata Busk, Challenger Zoology, Vol. X, Part I,
1884, p. 135, PI. XX, fig. 8. (PI. XV, figs. 3a-f).
The zooecia rounded hexagonal, rather strongly arched, strongly tuberculated and provided with numerous scattered pores. The aperture is broader than long, and the somewhat projecting anter consists of a crenulated, arched distal margin and two lateral margins, somewhat convex inwards, which converge proximally. The supporting beam is well-developed, without lateral teeth. The operculum, which is strongly chitinized, is provided distally with a much crenulated mar- ginal part and the muscles are attached to a small depression on each side within its proximal end. The ascopore which has dentated margins is half-elliptical and provided with an internal, narrow, elongated projection. Each zooecium is pro- vided in its distal half with 9 — 10 pore-chambers with 4—6 pores in each; 2 — 3 are destined for the distal connection. Further, the basal part of each zooecium is provided in its distal half with a small, few-pored rosette-plate and in its proximal half with an opening corresponding to an opposite rosette-plate.
The ooecia, which seem to have no pores, are exceedingly prominent and the strongly arched middle part may be so strongly marked, that it sometimes has a hunched appearance.
The heterozooecium is formed as a vibraculum and seems to be present on all the zo(L'cia in the colony. The large, strongly arched, oval chamber, the longi- tudinal axis of which is almost parallel with that of the zooecium, is situated on one side of the zooecium and does not reach over to the basal surface of the zooecium. It is connected with the latter by means of 10 — 12 uniporous rosette- plates. Us frontal surface is directed distally and the sword-like flagellum, which is provided with an oblitpie, triangular proximal part, points outwards (fig. 3 f).
The colony is free, two-layered, dichotomously branched and the single branches, which only slightly increase in breadth distally, have 8—16 rows of zooecia. The free margins of the colony are provided with a bundle of radical
330
fibres, which arise From the pore-chambers in the outer walls of the marginal zooecla, some of which have no aperture. At the beginning of the older bifurca- tions a bundle of radical fibres stretches obliquely across over the surface of a bifurcation to attach itself to the opposite margin of this, and this may some- times occur on both surfaces at the same time. Each of these radical fibres (fig. 3 e) is provided with two longitudinal rows of large, multiporous rosette- plates, each of which is surrounded by a calcified ring formed originally by a number of small pieces separated by sutures. Sooner or later, however, all these calcareous rings become connected with each other. P'urther, other radical fibies also occur in a very peculiar manner, as they everywhere surround the single zooecia and cover the sutural lines between these. The two layers of zocecia, of which the colony consists, are connected with one another in such a way, that a longitudinal row of zoa'cia in the one layer corresponds to a longiludinal row in the opposite layer; but the zoa?cia in two such opposite longitudinal rows alternate and each zooecium is connected with two zocecia in the opposite row. This is seen amongst other things from the manner in which the rosette-plates and openings of the basal walls are arranged.
Of this species I have examined two colonies from South Australia (Miss Jelly. Dr. Holub).
Microporella flabellaris Busk.
Eschara flabellaris Busk, Catalogue of Marine Polyzoa, Cheilostomata,
p. 91, PI. CVII, figs. 7—10.
(PI. XV, figs. 4 a-f).
The zocecia rounded hexagonal, fairly strongly arched, tuherculated and pro- vided witli numerous scattered pores. The aperture is broader than long and provided with a somewhat projecting anter, the proximally converging, generally concave lateral margins of which sometimes grade directly over into the distal margin and are sometimes marked otT from this by a more or less distinct angle. The supporting beam is well-developed with a more or less distinct, dcnlated edge, but without special lateral teeth. The operculum, which is well-chitinized with a marginal thickening on the antcr, is provided with a faintly convex proxi- mal margin, which on each side has a small, rounded thickening for a muscular attachment. The narrow ascoporc, which has toothed margins, is broader than long and there is sometimes a tuherculated projection proximally to it. Each distal wall is provided with 2 — 3 multiporous pore-chambers. Whilst the distal lateral wall, which is ojjposite the vibraculum, is provided with a multiporous rosette-plate, the other distal lateral wall has a pore-chamber and this abuts upon
331
the larger or smaller (in the figure fairly small) basal wall of the vibracular chamber. Through the basal surface of the distal half of each zooecium (fig. 4 c), therefore, we can see 4 — 5 chambers and in rare cases only 3, in which case the vibraculuni is wanting or does not reach to the basal surface. The basal surface in the majority of the zooecia shows in its proximal half either a multiporous rosette-plate or an opening.
The ooecia, which have no pores, are sti'ongly arched and luberculated.
The heterozooecia are developed as vibracula and occur singly on almost all the zooecia in the colony. The large, projecting chamber, irregularly circular in circumference, which is situated on one side of Ihe zooecium at a level with the ascopore and with its longitudinal axis perpendicular to that of the zooecium, is provided with a short mandible pointing outwards, which consists of a large, oblique, triangular proximal part and a not much longer, dagger-shaped terminal part (fig. 4 f).
The colonies are free, two-layered, dichotomously branched and the single branches, which are greatly widened at the end, have on each surface 8 — 45 rows of zooecia. Similar bundles of radical fibres appear along the margins of the colony as in the previous species; but on the other hand, radical fibres are want- ing round the single zooecia. The basal wall of most zooecia is in the proximal half provided either with a multiporous rosette-plate or with a corresponding opening and in opposition to what is found in Mic. marginatu the zooecia in the two layers of the colony correspond to each other.
Of this species I have examined a colony from South Africa (Miss Jelly).
Microporella flabelligera n. sp. (PI. XXIII, figs. 6a-6c). The zooecia edged oval, evenly arched, luberculated and provided with scat- tered pores, which decrease in number outwards and which owing to the thick- ness of the wall appear as canals in older zocrcia. The aperture which is sur- rounded by 5, more rarely 6 spines dark at the base, the two outermost of which are bifurcated, has a half-elliptical form, and its proximal, somewhat concave margin grades over into the lateral margins on each side round a right-angled, rounded corner. There is a distinct vestibular arch and a faintly developed supporting beam. The operculum is strongly chitinized, dark-brown and pro- vided on each side with a short muscular ridge, which runs out into a freely projecting terminal part. The ascopore, which is of a considerable size and cir- cular, has no inner protuberance and its margin may to a larger or smaller ex- tent be provided with teeth-like projections. Immediately on the proximal side
332
of lliis there is a large, obliquely ascending projection, with its level surface turned towards the ascopore. The distal half of each zooecium is provided with 3 — 4 elongated, multiporous pore-chambers.
The ocecia, which are cndooa'cial, but nevertheless prominent on the surface of the zooecium, are broader than high and provided within the membranous ectoooecium with a cryptocyst layer, which proximally to the aperture may run out into an irregular projection. There is a spine on each side of the aperture.
The heterozooecia, which occur in pairs on each zoa'cium, are in the form of vibracula and are situated one on each side of and a little proximally to the aperture. The oval or pyriformly oval frontal area is as in E. vulgaris and E. pes anseris provided with a distal concavity for the reception of the long, narrow, dark-coloured flagellum, which from a triangular proximal part terminates in a point.
Of this species I have examined a single, extremely small, incrusting colony, which shows superficial budding; Syracuse, rocky bottom, 15—25 fm. (Dr. H. J.
Hansen).
Arthropoma n. g.
Schizoporella Hincks p. p.
The zooecia lack a covering-membrane and are provided with scattered pores. The aperture, which has a distinct but low vestibular arch, is provided with a narrow, deep sinus, and the well-chitinized operculum consists of two parts con- nected by an articulation (i. e. a more weakly chitinized connecting part), a principal part, which is provided with two muscular dots and an accessory part, which occupies the sinus. Avicularia may be present. The ocecia consist of a calcified endoooccium without pores and a membranous ectooa^cium. The dis- tal half of each zooecium with three multiporous rosette-plates (often only groups of small, uniporous rosette plates) or three pore-chambers.
To this genus belong A. (Schiz.) Cecili And. and A. (Schiz.) circinata Mac Gill. Whilst the rosette-plates in the former may undergo a fairly considerable varia- tion, even in zooecia of the same colony, the elongated groups of small, uniporous rosette-plates being sometimes quite open, sometimes surrounded by a more or less projecting edge, we find in the latter species small pore-chambers with a single row of pores in each. Whilst .4. Cecili in contrast to A circinata as a rule has neither spines nor avicularia, a remarkable, spine-bearing, independent avi- cularium, the mandible of which is provided with a similar accessory part as the zocEcial operculum, has been found by Kirkpatrick' in a variety of the
' 48, p. 21.
333
former from the China Sea. In his description of ,4. circinata Busk mentions a supposed bundle of muscles, which is attached to the accessor}' part of the operculum, ])ul in reality it is only a connected part of the compensation-sac, which by foldings has assumed a longitudinally striated appearance.
Emballotheca n. g. Schizoporella p. p., Lepralia p. p.
No spines. The zoa'cia with numerous scattered pores. The aperture has a weakly developed vestibular arch and its poster is usually convex or provided with a low sinus, more rarely with a broad, tooth-like projection. The operculum, the muscles of which are attached near the lateral margins, is chitinized to a very varying extent and not always distinctly marked off from the compensation- sac. Well-developed hingc-tceth. Small (wkiiUiria with rounded mandible at the tip may occur in various positions, but are most frequently lateral with the mandible directed obliquely proximally or inwards. The hyperstomial oa'cium consists of a membranous ectoocecium and a calcified endoooecium with or without pores, but between the two layers there is inserted a more strongly calcified cryptocyst layer, provided with pores, which is often formed by three or four zocecia in common; in such a case it consists of just as many pieces separated by distinct sutures. The uniporous rosette-plates are fairly numerous.
To this genus belong E. (Schizoporella) fiircata Busk, E. (Lepralia) ([iKidrata Mac Gill, and E. (Schiz.) siibiminersa Mac Gill.
The most striking character of this genus, which for the rest comes nearest to Schizoporella, is the presence of a cryptocyst layer between the two layers of the ooecium, which may sometimes be formed by the distal zooecium alone, sometimes also by two or several adjacent zooecia, and in the last case this layer consists of three or several pieces meeting in distinct sutures. The reason for this difference is simply, that the basal wall of the ooecium only extends in the first case over a part of the distal zooecium, whilst in the last it also extends in over an adjacent part of the neighbouring zooecia, each of which then takes part in the formation of its frontal wall. The earliest sign of such an ocrcium is in E. [areata shown in zocrcia with frontal wall completely calcified, and it appears here as a hollowed-out area the boundaries of which are formed, some- times merely by a low, arch-shaped cryptocyst ridge, sometimes also by the lateral margins of the zoircium. The area mentioned like the rest of the surface of the zooecium is covered by a membrane, and the part of this which covers over the area is destined to become the basal wall of the ooecium, whilst the low ridge is the first .sign of the cryptocyst layer which grows into the oa^cial
334
fold. In those cases where the ooecial rover consists of several adjoining pieces, it is however only the distal piece which is early laid down as a low ridge, whilst there is yet no trace of the other i)arts which only appear later. Whilst I have not seen simple and conij)ound octcia on the same colony, colonies of the same species from different localities on the other hand present a difference in this regard. Thus, the 0(rciuni is simple in an incrusting colony of H. furaitd from Siam, which agrees in all essentials with a form from Singapore which appears in free, two-layered laminate colonies and in which Ihe ocrcium is com- pound. Whilst the form of E. suhiminersa figured hy Hi neks has a com[)ound ocecium, the ooecium in one of the colonies examined hy me frona Victoria is simple. The same difference is also seen in E. qimdrata, and Mac Gillivray for example figures a Tertiary form of this species with a simple ooecium.
Emballotheca quadrata Mac Gill. Lepralia quadrata Mac Gill., Mc Coy Prodromus of the Zoology of Victoria,
Vol. I, Dec. V, pag. 42, PI. 48, fig. 5. Eschara elegans Mac Gill, (non Milne Edwards) Transact, and Proceed R. Soc. of Victoria, Part II, Vol. IX, 1869, p. 138. (PI. XVIII, figs. 13a-13e). The zooecia rectangular, slightly arched, tnberculated and provided with scattered, fairly large pores. The aperture, which is placed immediately proxim- ally to the curved or angularly bent distal margin of the zoa'cium, is rounded quadrangular, somewhat broader than long, and provided with two concave, proximally converging lateral margins, whilst the proximal margin runs out into a broad, but low, rounded or trapeziformly rounded, tooth-like projection. Each lateral margin is provided with a long and strong hinge-tooth, bent proximally and inwards, which seen from the aperture appears as a rule pointed, but which in reality ends in a fan-shaped, dentated, nodulous exjjansion. The operculum, which is but incompletely delimited from the compensation-sac, is surrounded by a more strongly chitinized marginal part, which is continued proximally into a recurved part on each side. Each distal wall is provided with ca. 8 and the distal half of each lateral wall with 3 — 5 uniporous rosette-plates.
The ooecia, which are provided with a Ihin-walled endooa'cium perforated by pores, are circular in outline, evenly arched and very large, as they spread over a great part of the place occupied by the adjacent 4 — 6 zooecia. The cryp- tocyst layer lying under the ectoofi'cium is, like the rest of the cryptocyst, pro- vided with scattered pores and is thus composed of 4 — 6 sections meeting in
335
sutures. The aperture of the gonozooecia is considerably larger and broader than that of the ordinary zooecia.
The avicularia occur extremely rarely and most frequently singly in the dis- tal corners of the zooecia, but on the gonozorecia there is not rarely one on each side. They are concave, of a more or less regular, elongated oval form, and the opercular area, which is separated from the subopercular by an arched trans- verse ridge, is provided with a well-developed cryptocyst. The mandible points directly or obliquely proximally.
Of this species, which appears in free, two-layered plates, I have examined a dry fragment from Victoria (Miss Jellj').
Cyclicopora Hincks.
No spines and no distal arch. The zooecia have scattered pores and the cir- cular aperture, which has no hinge-teeth, is provided with a slightly chitinized operculum. No avicularia. The oa>cia consist of a membranous ectoooecium and a calcified endoooecium provided with scattered pores. Multiporous rosette-plates.
The genus, which only comprises a single species C. praelonga Mac Gill. (C. lon(jipora Hincks), is referred by Hincks to a separate family Cijclicoporidae, which is based in general on the simple structure of this form and not on def- inite positive characters. The most important, systematic character is shown in the ooecia, which agree essentially with the corresponding structures in the family Escharellidae, consisting of a membranous ectoott'cium and a calcified endooa-cium. They differ however from all other ooecia in this family, in that their basal wall is formed in the whole of its extent by a portion of the frontal wall of the distal zooecium, whilst this only partially occurs in such genera as Escharella and Escharoides. This genus is therefore provisionally and with great doubt referred to the Escharellidae.
Family Smittinidae.
The zooecia are seldom provided with 1 — 8 spines. A vestibular arch is wanting or weakly developed. The avicularia are rarely lateral and a median, symmetric- ally or asymmetrically placed avicularium appears most frequently. The owcia have as a rule a calcified, very rarely a membranous ectoooecium which is usu- ally provided with pores. Rosette-plates with one or several pores, more rarely pore-chambers.
The two families Smittinidae and Escluirellidae are not sharply distinguished, and a comparison of the characteristics of the two families shows that the char- acters taken singly may appear in both families, though to a very different ex-
336
tent and in different combinations. The most constant difference is seen in tlie structure of the ooecia, but in this regard the genus Porella forms a connecting- link between the two families, as a number of species of this genus have a mem- branous ectoooecium and pore-chambers.
Porella (Gray) Hincks.
Spines are wanting or appear at most to the number of two. The primary aperture has a straight, slightly convex or somewhat concave proximal rim, which is often provided with a broad or low median tooth. Distinct hinge-teeth are as a rule present. A distinct peristome. The operculum, which in the rarest cases is somewhat strongly chitinized and sometimes not separated from the compensa- tion-sac, is as a rule provided within each lateral margin with a more or less strongly developed muscular ridge. Immediately proximallj' to the aperture there is in most species a large ouicularinni, the chamber of which often takes uji al- most the whole of the breadth of the zooecium, and its distally directed frontal area is in time enclosed within the peristome. The ooecia, which have no pores or at most a single one in the oa>cial cover, have sometimes a membranous and sometimes a calcified ectoocrcium. In the latter case there is in addition an oce- cial cover formed in various ways. Multiporous rosette-i)lates, niore rarely multi- porous pore-chambers.
Numerous species belong to this genus, amongst which are P. concinna Busk, P. marsiipiiun Mac Gill., P. margaritifera Quoy & Gaim., P. aciilimstris Smilt, P. miniita Norm., P. comprcssn Sow., P. glaciata Waters, P. plana Hincks, P. Skciiei Ellis & Sol., P. saccata Busk, P. injUita Waters (= P. laeuis Sniitt, pars), P. prin- ceps Norman, P. tiibulifera Heller.
The species may be divided into two groups (or perhaps genera) according to the structure of the ocrcia, these in some species e. g. P. aciitiroslris, P. mar- 9 — - supiiim and P. margaritifera having a membranous ectooa'cium, whilst the ecto- ooecium most probably in most species is calcified. Whilst in the former group the calcified endoooeciuni gradually increases in thickness under the covering membrane, an ooecial cover foimed in different ways may appear in the second group. In P. struma and P. glaciata it is a single cryptocyst layer, which again is covered by the covering membrane, whereas in P. saccata it is many-layered, as thin calcareous layers, presumably gymnocyst layers, continually grow over the ooecium, not only from the distal zooecium but also from the two neigh- bouring zooecia, and we can see as a rule three, distinctly separated, thin cover- ing plates on their surface. P. saccata ought perhaps to be referred to a distinct genus.
337
Porella margaritifera Quoy & Gaim. Flustra margaritifera Quoy & Gaimard, Voyage de TUranie, Zoologie, p. 606,
PI. 92, figs. 7, 8. Lepralia margaritifera Busk, Catalogue of Marine Polyzoa, Cheilostomata, p. 72,
PI. CI, figs. 5, 6. Flustra margaritifera Jullien, Mission du Cap Horn, Bryozoaires, 1888, p. 58,
PI. 9, fig. 1. Lepralia margaritifera Waters, Challenger, Zoology, Vol. XXXI, III, 1889, p. 26,
PI. Ill, figs. 15, 16. (PI. XVIII, fig. 8 a). The zocecia elongated, hexagonally lyre-shaped, strongly arched and provided with a circle of marginal pores. These soon come to lie in areas, hounded by ribs, which radiate in from the margin to the suboral avicularium; and with the continued deposition of the calcareous substance these areas are at length transformed to pear-shaped pits. The ajierture has a semicircular anter, and we can distinguish in this between a straight or slightly convex, median part and two short, curved, distally diverging lateral parts. Small distinct hinge-leeth. The operculum, which is not separated from the compensation-sac, is weakly chitinized and provided on each side with a chitinous ridge, which is slightly angularly bent and its proximal portion is in the greater part of its length far removed from the margin. The strongly curved or angularly bent distal wall is provided on each side with a row or zigzag belt of small, uniporous rosette-plates, and the distal i)art of each lateral wall has one multiporous rosette-plate.
The ooecia, which on the colonies examined occur on the majority of the zod'cia, seem only to consist of a single, independent calcareous layer and have therefore probabh' been covered by a membranous ectoooecium. They are ori- ginally furnished with fine radiating striae, but in older zooecia they show con- centric thickenings arising from the covering calcareous layer.
Avicularia. The suboral avicularium, which has a broad, triangularly rounded mandible and a broad, .sac-like chamber, does not attain quite a third of the whole length of the zooecium. In the older zooecia it shows like the ooecium con- centric thickenings. In one of the small colonies examined a number of zooecia are provided immediately distally to the ocBcium on the one side with an avi- cularium somewhat variable in size, which is of an irregular elliptic form, as it increases in breadth towards the distal part of the opercular area, and this espec- ially in the larger avicularia is provided with a well-developed cryptocyst. In the younger zooecia these avicularia, the mandible of which is as a rule directed
22
338
obliquely distally and outwards, project freely from the surface of the zoocciuni, but in the older zooccia they become more or less deeply sunken owing to the above-mentioned deposition of calcareous layers. At their base we find as a rule two of the above-mentioned, original calcareous ribs, which from their position have not been able to share in the increase in thickness like the others.
Of this species I have examined some small, dry colonies from Foveaux Straits, N. Zealand (Dr. Harmer).
Porella (?) cornuta n. sp.
(1^1. XYIII, figs. 6a-b, PI. XXII, fig. 11 a).
The zocecia elongated, quadrangular or hexagonal, fairly strongly arched, with closely placed, scattered, large, round or oval pores, between which are numerous small tubercles. The half-elliptic aperture is provided with a very broad but extremely low sinus, which has a straight or slightly convex, proximal margin and is marked olT on each side from the lateral margins by a small, rounded, tooth-like projection Immediately distally to and inside this projection, there is on each side a rounded, triangular hinge-tooth, which is continued into a weakly developed vestibular arch. In the distal part of the aperture the peristome is only weakly developed, but in its proximal half there is on each side a collar- shaped, prominent, fairlj' thick projection, which on each side grades into the avicularium and in the ocecium-bearing zocEcia meets the proximal part of the ocEcium, whilst in the other zooecia it is sharply marked off from the low distal part of the peristome. The operculum (PI. XXII, fig. 11 a), which has a similar form as the aperture, is only slightly chitinized but distinctly separated from the compensation-sac. On each side within the margin it has an elongated, strong ridge and the two ridges pass over both distally and proximally into a somewhat strongly chitinized, but not very distinct, connecting part. Each distal wall is provided with two and the distal half of each lateral wall with one multiporous rosette-plate.
The Goecia are as a rule elongated, more or less distinctly tapering upwards, strongly arched and with their frontal wall inclined down towards the aperture. They are in the beginning furnished with fine radiating striae, but owing to later calcification this slriation becomes more and more indistinct, and the older ooe- cia are not only provided with smaller and larger tubercles and with rib-like prominences of varying form, but most of them have even one or several, shorter or longer, sometimes very long, hollow spine-like processes of more or less reg- ular form. There is often such a process standing out almost perpendicularly from the surface of the ooecium.in the neighbourhood of the aperture on both
339
sides or only on the one side, and a third frequently projects at the same time from the middle of the ooecium. The processes mentioned arise in this way, that some of the above-mentioned rib-like prominences are ring-shaped and continue to increase in height. The ooecium in a larger or smaller part of its circum- ference is connected with the zod'cium by means of rib-like prominences.
As I have been unable to find any more than a single independent calcareous layer, I conclude that there has been a membranous ectoocccium, by means of which the thickening layer has been formed. The oa>cium lacks a basal mark and has presumably been formed later than the cryptocyst of the zooecium.
Avicularia. Immediately proximally to the aperture of the zooecium there is a strongly projecting avicularium, standing out at right angles, the chamber of which is almost of the same breadth as the aperture. Seen from the side it is pointed, triangular, and seen from its mandibular surface it has a rounded, tri- angular form. It is provided with an oval aperture but I have been able to find neither a mandible nor trace of transverse bar.
In the conchological collection of the Zoological Museum a single dry colony was found incrusting Saxidonnis piirpiinttiis from Yokohama.
The above-described species is only referred with some doubt to the genus Porella.
Stnittina Norman' (nov. nom.) char, emend.
Escharella (with subgenera Escharella s. str. and Hserentia) Smitt,
Smittia Hincks, p. p., Schizoporella Hincks, p. p., Pseudofiustra Bidenkap.
Spines may be present to a number of 1 — 8. The aperture is provided with a more or less distinctly marked off, as a rule broad, rounded sinus, which sometimes takes up the whole of the proximal margin and the middle part of which is often occupied by a tooth of varying shape. There are well-developed hinge-teeth as a rule. The operculum is in most species membranous or weakly chitinized, often not marked off from the compensation-sac. A peristome may be absent or jjresent in very different degrees of development. Avicularia may appear in verj' varying positions, but one is usually present proximally to the aperture. The ooccia, which in most cases are either independent or have only a small part of their endooa?cial basal wall common with the frontal wall of the zooecium, consist of two calcareous layers, of which the ectoooecium is with few exceptions provided with pores. As a rule there is a more or less developed ocecial cover. The rosette-plates are sometimes uniporous, sometimes with a few or many pores.
' 84, p. 120.
22*
340
Of Ihe species which I have been able to examine I must refer the following to this genus: S. Lansborovi Johnst., S. reticulata Mac Gilliv., S. trispinosa Johnst., S. JefJ'reysi Norman, S. iinispinosa Waters, S. cheilosloma Manz., S. jacobensis Busk, S. (Porella) malleolus Hincks, S. arctica Norman, S. inajiiscula Smitt, .S. porifera Smitt, S. reticulato-piinctata Hincks, S. Smitti Kirch., S. {Pseiidoflustra) solida Stimps., S. {Eschara) prnpinqua Smitt, .S. (Lepralia) borealis Waters, S. (Schizoporella) linearis Hassall, S. (Schiz.) aiiriciilata Hassall, S. (Schiz.) triangula Hincks, S. (Lepralia) foliacea Ellis & Sol., S. (Lepralia) Otto-Muelleriana (= S. Pallasiana, var. projecta Waters), S. (Lepr.) coUaris JuUien (= Lepr. Pallasiana, var. striinmta Waters) and vS. (Lepralia) Pallasiana Moll.
While originally I only referred to this genus species with uniporous rosette- plates, the aperture of which besides two well-developed hinge-teeth is provided with a median tooth and the ectoooecium of which is provided with pores, for instance S. Lansborovi, S. reticulata and S. trispinosa, I have been obliged gradu- ally to extend the limits of the genus in the manner expressed in the above dia- gnosis, seeing that the species in which the three characters named are constant through transitions are connected with species which I was earlier inclined to refer to one or more other genera. As to the rosette-plates a number of species (e. g. S. linearis, S. auriculata, S. malleolus etc.) have on each lateral wall 3 — 5 uniporous plates while others (e. g. S. porifera, S. reticulato-punctata, S. solida, S. Smitti) have 2 — 3 with 1 —5 pores and a third group (e. g. .S. propinqua, S. foliacea, S. collaris and S. Pallasiana) have 1 — 3 with 6 — 30 pores, the number of rosette-plates decreasing in inverse proportion to the number of pores in each plate. A distinction between uniporous and multiporous rcsette-plates cannot therefore in these species be used as a generic character. A median tooth which as systematic character is always more or less inconstant cannot be used here either as a decisive generic character, as it is not always constant even within the species. This applies for instance to S. solida and »S. Smitti, in which two species a median tooth may sometimes be present and sometimes absent.
Quite apart from the fact that the proximal margin of the aperture in a number of species is provided with a median tooth, it also shows considerable differences in the form as well as in the breadth and the depth of its poster, which is very often furnished with a more or less distinct sinus. The sinus is narrowest in 5. linearis and shows here considerable variation in forms from different localities Whilst in a form from Bergen, for example, it is half as broad as the aperture, in a form from Syracuse it attains only a fourth of the breadth. To exclude all doubt as to these forms being connected, I may remark, that in addition to both having the two lateral aviculaiia they are also provided with
341
the peculiar large avicularia, which Hincks took to be occcia. The broadest sinus is found in S. collaris and .S. Pallasiana, in which two species it is the broadest part of the aperture. The operculum, which is never provided with mus- cular ridges, is in most species membranous or feebly chitinized and very often not or only indistinctly separated from the compensation-sac (e. g. in S. Smitti, S. Lansboroui, S. reticulata, S. trispinosa), while in other species such a separation is brought about either by its stronger chitinization (e. g. in S. propinqiia et S. Im-ealis) or by the development af a chitinous sclerite along its proximal margin in continuation of the opercular arch (e. g. in S. solida, S. reticulato-punctata, S. collaris, S- Otto-Muelleriana, S. foliacea and S. Pallasiana).
The avicularia may occur in very different positions and we can sometimes hnd both two lateral as well as a single median avicularium in the same species (e. g. S. trispinosa and S. linearis). This occurs for example in the same colony of the above-mentioned S. linearis from Syracuse. In this genus however there is usually a sometimes symmetrically, sometimes asymmetrically placed, median avicularium proximaily to the aperture, and it may be noted as a contrast to the corresponding avicularium in the genus Porella, that the median avicularium in Sniittina has its frontal area as a rule parallel to the surface of the zoa>cium.
Whilst the ectoooecium is as a rule provided with numerous pores, the number of these may fall to 3 or 2 in vS. trispinosa and the same number is also found in S. foliacea. In .S. arctica there is only a single pore, and finally pores are quite wanting in S. Smitti and S. majnscula. An ooecial cover is present in most species but in very different development, sometimes only forming a marginal belt (e. g. in S. Lansboroui, S. borealis, S. collaris), sometimes concealing the whole frontal wall of the ooecium and developing together with it (e. g. in S. Smitti, S. arctica, S. majnscula). Its appearance in .S. trispinosa var. cncuUana (PI. XIX, fig. 7 a) is characteristic, as it is provided there with a freely projecting, prominent margin, as also in N. foliacea (Fl. XXIV, fig. 5 a) where it consists of three parts, which are separated by two sutural lines converging towards the aperture. The middle part belongs to the distal zocecium, whilst the two lateral parts belong to the two neighbouring zoa>cia, and the two characteristic, large, flatly triangular pro- jections, which partially cover the aperture of the ooecium-bearing zocecia, are directly connected with the lateral parts of the ooecial cover. Only the proximal part of the ooecium is covered in S. solida.
Though calcareous ooecia have not been found in >Lepralia^ Pallasiana I must refer this species to the present genus on account of the likeness it shows to S. Otto-Muelleriana in the structure of the aperture and the operculum, in the
342
possession of scattered pores and of an occasionally present median avicularium proximally to the aperture.
Smittina acaroensis n. sp. (IM. XVIIl, figs. 12a-l)).
The zooecia are usually elongated, with an arched or angularly bent distal wall and as a rule with parallel lateral walls. They are provided with a single or double circle of marginal pores, soon separated from one another by ribs which after a time increase in height and length, and in the oldest zoo'cia the whole surface is divided into a number of depressed areas; the latter may even conceal the chamber of the avicularium. The aperture, the distal margin of which is finely dentated and in the younger zooecia bears the marks of 4 spines, is pro- vided with a somewhat distinctly marked off, broad and deep sinus, the middle part of which is occupied by a fairly broad tooth, a.\e-like in shape and running out into two pointed corners. The two hinge-teeth are strong, triangular, some- what pointed, more or less strongly striated and curved somewhat j)roximally. The operculum is membranous, not distinctly separated from the compensation- sac and provided on each side with a very faint chitinous ridge. The peristome is collar-shaped, prominent, and provided with an excision corresponding to the frontal area of the avicularium. Each distal wall is provided with 8 and the dis- tal half of each lateral wall with 3 — 5 uniporous rosette-plates.
The ooecia, which are present in great number, are large, as a rule some- what elongated, fairly strongly arched and provided midway with numerous, larger and smaller pores. An orecial cover appears after some time and in older ooecia only leaves a narrow, central part free.
Avicularia. An avicularium is present proximally to the aperture, the length of which is almost a fourth of that of the zoa'cium and which takes up the greater part of the breadth of the zooccium. Its chamber, which is separated from the zocecium by a broad, arched line, is provided at the margin with 3 — 5 pores, and the transverse bar which divides the oval frontal area into two parts, is provided with a short, proximally directed process. The subopercular area, which is turned towards the aperture, has a transversely oval opening.
The colonies occur as free, two-layered laminne, and the species was found in mud from Akaroa Harbour, New Zealand (Suter); depth 6 fathoms.
343
Discopora ' Lamarck. Escharoides Smitt, part., Umbonula Hincks, Mucronella Hincks, part., Raniphostomella'- v. Lorenz. (PI. XIX, figs. 2 a— b, fig. 19 a).
Two to four spines occur very rarely. The primarj' aperture always lacks hinge-teeth, but is often provided with a fairly narrow, median tooth. The oper- culum is membranous and not separated from the compensation-sac. Symmetric- ally placed aviciilaria very seldom occur; but a larger or smaller part of the aperture is as a rule on its proximal margin occupied by a larger or smaller, usually strongly projecting avicularium, which may be lateral or median, but frequently has an asymmetrical position. The oa'cia, which have a small basal mark, consist of two calcified layers, of which the ectoocecium is provided as a rule with pores. The distal half of each lateral wall is provided with 1 — 2 multi- porous rosette-plates.
To this genus belong of the northern species: ^ Escharoides^ Sarsi, ^Umhonula< verrucosa, "Miicronelhix pavonella (which Harmer has already referred to the genus Umbonula), as also the species of the genus Ramphostomella, v. Lorenz. To the latter genus v. Lorenz^ refers 6 species, but the material investigated by me seems to show, that R. costala v. Lor. is not sufficiently distinct from R. scabra. To these has to be added R. ovata Smitt. The genus Discopora stands near to Siniltina, from which it differs by the lack of hinge-teeth, by never po.ssessing a symmetrical sinus, by always having some few multiporous rosette-plates, as also generally in the position of the avicularium. The limits between the two genera are however not so clearly marked but that we could imagine them dis- appearing on investigating a larger material.
The primary aperture, which may be more or less regularly circular or semi- circular, has sometimes a concave, sometimes straight or somewhat convex proxi- mal margin, and in the first case it may be provided with a more or less dis- tinct, narrower or broader sinus (D. Sarsi, D. spinigera, D. bilaminata). Whilst the hinge-teeth are always lacking, a very inconstant median tooth may however appear in most species (lacking in D. Sarsi and I), verrucosa), and there are also in several species one, two or several, conical or trapeziform teeth, as a rule ex- tremely small on the proximal margin of the aperture. Thus, such a tooth oc- curs as a rule on the one or both sides of the above-mentioned, asymmetrical sinus, and in D. Sarsi the number of these small teeth may sometimes mount
' 84, p. 112. ■ 58, p. 93.
344
up to 4. There is only a single one however as a rule at the subopercular end of the avicularium, but not rarely there is a still smaller one centrally in the sinus. There is also sometimes such a small toolh in D. plicnta on the oral margin of the avicularium, hut so jilaced that it cannot be seen from the frontal surface of the zoa'cium. Whilst a peristome is either quite wanting or weakly developed in those species, which either lack an oral avicularium {!). pavonelki) or in which it has a more or less distinctly median position (I), verrucosa, D. scabra), it is on the other hand more strongly developed in the other species in which the oral avicularium is lateral. Here, namely, the peristome appears in the form of two projections from the proximal margin of the aperture separated by a triangular incision, and the one of these projections along with an adjacent part of the frontal wall of the zooecium serves as the basal wall of the avicul- arium. What Hincks and v. Lorenz call an avicularium in their diagnoses of the genera Umboniila, Escharoides and Ramphostoinella is in reality only the frontal part of the avicularium with the mandible, whilst the avicularian chamber, which contains the muscles, seems to have been either overlooked or regarded as some- thing supporting the avicularium. In Hincks' diagnosis of the genus Escluiroides it is said, namely, that the avicularium is enclosed within a sinus, formed by the peristome, while this in reality only applies to the frontal area of the avi- cularium, and in the diagnoses of Umbomila and Hcimpliostoinella the avicularian chamber is described respectively as »a prominent umbo (? avicularian cell) . . . supporting an avicularium* and as »ascending rostra . . . bearing avicularia«.
The ocecia, which only have a small basal mark, show a similar variation in their structure as in the species of the genus Smittina. As a rule the pores are fairly numerous, though their number may sometimes vary considerably in a single species. Thus, in a colony of D. bilamimild 1 have found the number of pores varying between 7 and 2. hi D. Sarsi there is only 1 or 2, and they are quite wanting in D. ovaia which also differs from the other species in that the zoojcial wall is provided with scattered pores. An ooecial cover is present in most species and appears as a rule in sufficiently old oa-cia as a covering lamina in the marginal region of the ooecium. It is well-developed in D. verrucosa and D. scabra, which resemble one another in most respects and differ chielly in that the avicularian area in the latter is placed asymmetrically. An oa>cial cover is most strongly developed in D. Sarsi (PI. XXIV, lig. 2 a) and the ocecia are here rather quickly covered by 3—5 ditt'erent calcareous laminae meeting in a suture, the two proximal of which come from the peristome, the unpaired from the dis- tal zocecium and the remainder from two neighbouring zocecia.
345
For the rest, all the species mentioned here will be made the object of more detailed investigation in a later work on the Bnjozoa material of the Ingolf Ex- I)edition.
Family Celleporidae, char, emend. Celleporidae liusk, Hincks, part.
No spines. The aperture as a rule circular with a broader or narrower, more or less sharply marked off sinus, more rarely with a simple, concave, proximal margin. Hinge-teeth may be absent or present. The operculum is always dis- tinctly marked off from the compensation-.sac, weil-chitinized as a rule and pro- vided with two muscular dots. A peristome more or less developed present as a rule. Avicidaria seem to be always present, and in most species a more or less strongly projecting, almost always asymmetrically placed avicularium is present proximally to the aperture. Further, large scattered avicularia often occur. The hyperstomial ooecia are free and the ectoocecium is wholly or partially calcified. The basal zooecia have a rhombic circumference and their distal half is as a rule provided with a number (ca. 8) of adjoining, uniporous or few-pored pore- chambers, more rarely with few, widely separated pore-canals. The colonies, which are encrusting or freely branched, as a rule show superficial budding, and the zooecia are often more or less erect.
The aperture is provided as a rule with a sinus, the dimensions of which are subject to very considerable variation, as can be seen, for example, from the figures of the aperture and operculum given by Busk'. Whilst the opercular tongue and the sinus are in some species very narrow and sharply marked, in others the latter is broadly rounded and so faintly marked, that there is a plain transition to the almost quite circular aperture which is found in a smaller number of species, e. g. in Cellepora pumicosa and Cell. (Lagenipora) socialis. The form of the aperture seems therefore not available as a generic character and the same is also the case apparently with the peristome, which is sometimes devel- oped to a very varying extent in the same species, e. g. in C. Costazzi. As the majority of the members of this family show superficial budding, the rosette- plates only appear on the zooecia in the basal layer of the colony, and in the large majority of the species I have been able to examine, each zocrcium in its distal half shows a number of juxtaposed uniporous or few-pored pore-chambers, which are apparent through the basal wall when the colony is loosened from its under-layer. In two species, which occur in very small colonies, namely, in
' 8, PI. XXX and XXXVI.
346
Cell. (Lagenipora) socialis and Cell. (Celleporella) pijijmaeu, on the other hand, there is on the circumference of each zooeciuni a small number (6—8) of widely sep- arated, thin canals by means of which each zooecium is connected with its neigh- bours. At the bottom of each canal there is a rosette-plate with one pore. This agreement in regard to the interzocecial connection cannot however be considered as an index of a close relationship between the two species mentioned, as we must refer them to two diJTerent genera owing to a presumably more important difference in the structure of the oa'cia.
hi the majority of the species belonging to this family the ooccium consists of two calcareous layers, of which the ectoooecium is as a rule provided with [)ores. These may however be lacking in a few species, for instance in Cell, soci- alis and in C. ramiilosa the ooecia are only rarely provided with pores, hi a small group of species, concerning which Waters' has already expressed the ojjinion that they should form a special genus owing to the structure of the ooccium, the ectoooecium is only partially calcified, and the frontal wall of the endoooecium has a flat, semilunar, semicircular or circular area which is covered by a mem- branous part of the ectoocucium, whilst the part of the endooa'cium correspond- ing to the area is provided, sometimes with radiating grooves or fissures, sometimes with scattered pores. For this group we would propose the name Siniopelta. An ocrcial cover may sometimes appear, for instance in Cell. ai)iciil(tris- and Cell, socialis.
Cellepora Linne. Cellepora Busk, Hincks part.; Olleporella Hincks part.; Lagenipora Hincks, Scliismojiora Mac Gillivray part.; Osthimosia Jullien.
The ectoooecium is wholly calcified and generally furnished with pores, in lare cases without such. With exception of Cellepora Costazzi all the species of Cellepora described by Hincks in British Marine Polyzoa belong to this genus, and with exception of C. riidis all those which Busk refers to the group S 2 in his Challenger Brtjozoa. Other species have been described by Mac Gillivray, Waters, Jullien and others. To this genus I must also refer Lagenipora socialis Hincks, of which 1 have examined a number of colonies lent me by the British Museum and by Mr. Waters. The ectoooecium is without pores but wholly calcified and furnished with an ooecial cover which hides its basal half. Among the ordinary zooecia there is a number of flat kenozooecia wliich Hincks men-
' 113, p. 13; 108, p. 20. « 103, PI. IX, figs. 194—96,
347
tions as a »common calcareous crust* and possibly tlie genus might be preserved on account of this character.
In his work on the British Zoophytes Johnston gives Fabricius as the author of the genus Cellepora, but the first author who used this name was in reality Linne in tlie Xllth edition of his Systema Naturae, and tlie first species he refers to this genus is C. ramulosa.
Genus Siniopelta n. g. Cellepora Busk, Hincks, part.; Celleporella Hincks, part.; Schismopora Mac Gillivray' part.; Osthimosia Jullien^ part.
The endoooecium has a flat frontal area furnished either with radiating fis- sures or with pores and covered by a membranous part of tlie ectoooecium.
To this genus belong C. Costazzi Aud., Celleporella pygmaea Norman (Cel. lepra- lioides Norman), Cellepora Boriji Aud.' (Lekythopora Wafersi Calvet*), Lagenipora lucida Hincks, Cel. graniim Hincks, Cel. costaia Mac Gill.'', Cel. platalea Mac Gill.^ Cel. rota Mac Gill. \ Cel. riidis Busk etc.
The ooecia of Cell. Boryi are not as Gal vet states frontal but spring from the distal rim of the aperture. Tlie form of the peristome seems to be somewhat variable.
Family Holoporellidae n. f.
Spines may appear in a number of 2 — 5. The aperture, which only rarely lias hinge-teeth, has a concave or almost straight proximal margin, which may sometimes be provided with 2 — 6 extraopercular teeth of dilTerent form. The operculum, which as a rule is weakly chitinized and often grades without bound- ary into the compensation-sac, is frequently provided with a ridge-like projection within each margin. A peristome may be absent or present, but is never strongly developed. A more or less strongly projecting, obliquely placed avicnlarium occurs as a rule proximally to the aperture, and large, scattered avicularia further often appear. The oaxia, which only occur in a small number of species, are widely open, consisting of a single calcareous layer, and in shape like a cap or bowl without pores; they seem to have no covering membrane. The zoa^cia in the basal layer of the colony, wliich have a rectangular circumference, aie provided both on the distal wall and on the distal half of each lateral wall with a row
' 76, p. 109. ' 45, p. 64. ' 98, PI. 7, figs. 3,1—3,6. ^ 10. p. 68, PI. 2, figs. 10—13. ' 61, p. 136. ' 68, p. 114. ' 68, p. 116.
348
of (respectively ca. i — 6 and 3^4) small, uniporous rosette-plates. The colonies are incrusting and superficial budding occurs in most.
Whilst s])incs never occur in any member of the family Celleporklac, such are found on the other hand in a number of species of this family to a number of 2 — 6, e. g. in » Cellepora<< apiculata Busk, C. trulenticiilatu Busk, Cellepora brimnea Hincks, C. verrucosa Mac Gill., C. hicirrhata Ortni., C. triacantha Ortm." and Dis- coporai aduena Smitt. The aperture has a concave or straight proximal margin, and though this in very rare cases may have a slight, rounded incision centrally, it cannot be compared with the sinus in Cellepora. This sinus is in reality the interspace between the two hinge-teeth or the two corresponding places of sus- pension for the operculum, whereas in the species mentioned as in all the other species of the family Holoporellklae, the hinge-teeth or the corresponding places of suspension for the operculum are situated on the lateral margins, which are well-separated from the proximal margin. Another difference lies in this, that this excision is not as the sinus in Celleporulae occupied by an opercular tongue. Such a small, rounded incision is found for instance in 'Schiznpnrelld' aperta Hincks, which belongs in reality to this family. In not a lew species the proximal maigin of the aperture is provided with a row of 3 — 6 teeth of varying form but usu- ally high or narrow, all of which are situated outside the operculum, so that none of them can be compared with hinge-teeth. Such teeth, which presumably serve to protect the operculum, are found in C. liiherciilata Busk, C. honoliilensis Busk, C. Jachsoniensis Busk, C. tridenticiilata Busk, C. pohjmorpha Busk, C. serrati- rostris Mac Gill.', C. hicirrhata Ortm.-, C. transversa Orlm.'~ and 'Discopora^ ad- vena Smitt.
The oa^cia, which occupy the greater part of the margin of the aperture, are widely open, have no pores and consist only of a single calcareous layer, which seems to lack a covering membrane; but as the ooecia-bearing species I have been able to examine were almost all dry specimens, I cannot determine this question with certainty. If a covering membrane is really lacking, they must i)ro- bably be regarded as peristomial, but in any case they are veiy dillerent from the ooecia in the Celleporidae. Good drawings of such ooecia are seen in Hincks' figures of ySchizoporella<!^ aperta-' and ^Monoporella<^ albicans^ and in Waters^ figure of Holop. Descostilsi And. Superficial budding occurs in this family just as in the family Celleporidae, and the rosette-plates therefore only occur in the basal zooecial layer. The zooecia in this family in contrast to the foregoing have a rectangular circumference, and both the distal wall and the distal half of each
' 68, p. 114. ' 87, p. 55. ' 26, p. 126. * 26, p. 123. ^ 116 a, p. 162.
349
lateral wall are provided with a row of small uniporous rosette-plates, of which those of the distal wall are often separated by small calcareous thickenings, which can be seen through the basal wall of the colony.
This family is very rich in species and the majority of the species have been described by Busk, Mac Gillivray, Ortmann and others under the name Cellepora, which generic name however with them also embraces the species of the family Celleporiclae. In his work on the Brj'ozoa of the Challenger Busk divides the genus Cellepora sens. ext. into two groups, mainly after the form of the aperture and the structure of the operculum, and with exception of Cellepora rudis which belongs to our new genus Siniopelta all the species which he refers to the group § I belong to the family Holoporellidae. From 1895 Mac Gillivray uses the name Cellepora exclusively for the species we have referred to this new family and forms a new name Schismopora for the species of the family Celle- poridae. Since however Cellepora ranudosa L. is the typical species for the genus Cellepora, Mac Gilliv ray's use of this generic name is quite incorrect. As ex- plained above, some few species are described under the generic names Scliizo- porella, Monoporella and Discopora.
A detailed, comparative investigation of the separate species will possibly make it necessary to set up several genera, but provisionally we must refer them all to a single genus.
Holoporella Waters'.
Cellepora Busk, Hincks pari.; Cellepora Mac Gilliv. (after 1895).
Monoporella Hincks part.; Schizoporella Hincks part.;
Discopora Sniitl part.
The two families Celleporiclae and Holoporellidae, the species of which compose the main part of the old family, Celleporidae, seem in all essential characters to be well-separated in spite of their great resemblance in appearance, due in part to the superficial budding aiul the more or less erect zoa'cia, in part to the strong armature which in both families has a very similar character. This armature appears in fact in a double form; we have in the first place a great development of avicularia, which occur not only on the single zooecia but as a rule also scattered over the surface of the colony as independent avicularia. In the second place we find in a great number of species the colony bristling with rostra or pointed projections, which sometimes belong to the zooccia, some- times to the avicularia. The strong armature shown by these two families might
' IK) a, p. 159.
350
possibly be regarded as the result of the superficial budding and be intended to protect the numerous new zooecial rudiments, which arise everywhere on the surface of the colony between and outside of the older zooecia. This form of budding may also be rendered easier by the more or less erect position of the zoa>cia, as the new zoa?cia are in fact laid down in the hollows between the older, so that a larger or smaller part of the walls of the latter come to take j)arl in the boundaries of the new zooecia.
Family Petraliidae n. f.
The zoa'cia which are only rarely provided with spines have scattered pores and an aperture somewhat variable in form, the proximal margin of which is in most cases provided with 1 — 3 extraopercular teeth. Hinge-leelh may be want- ing or present. The operculum, which may be more or less chilinized, is often almost membranous and not distinctly separated from the compensation-sac. A peristome is wanting or only weakly developed. Aviciilaria occur in all the spe- cies in varying positions, but one or several, obliquely placed avicularia usually occur just proximally to the aperture, and these may be situated on a rostrum- like projection of varj'ing form, which in rare cases may appear without being accomjianied by avicularia. The ooecia, which are first laid down after the cryp- tocyst of the distal zooecium is completed, consist of a membranous ectoooecium and a calcified endooo'cium [)rovided with very small, closely placed pores. An ooccial cover seems to be wanting. The distal half of each lateral wall is pro- vided with 3 — 8, as a rule few-pored, very rarely uniporous rosette-plates. With few exceptions the colonies are free, one-layered, laminate, and in such cases the basal wall of the colony is provided either with rmmerous pores or more fre- quently with one or a few pore-chambers placed at the distal end, from which radical fibres sometimes issue.
To lliis family I must refer the following species, of which I only know the first 6 from personal observation: Petralia iindata Mac Gill'wr.^, ^Lepralio" japonica Busk, L. redilineatd Hincks, »MiicroneIla-^ caslanea Busk, .1/. bicaspis Hincks, M. porosa Hincks, M. i>nltiir Hincks, ^1/. lilleri Mac Gillivr. ', .1/. aincnlifera Hincks, .1/. imuinifwa Busk, M. bisinmita Smitt, M. Thenardi Kirkp., ^Leprnlia- dorsiporosa Busk and L. tuberosa Busk. To these must be added two undescribed species from Singapore, of which the one, belonging to the same group of species as A/. /Joro.90, is remarkable for possessing two lateral jjlates for the attachment of the occlusor muscles of the operculum, similar to those known from the genus Chaperia. As
' 01. p. 141. ' 01, p. 135.
351
I only know so few of the above-mentioned species from personal observation, I must provisionally refer them all to a single genus Petralia Mac Gillivray; but I do not doubt that this will in time be divided into several.
In spite of the great variation shown by most of the characters the separate species in this family are so closely connected by many agreements that there can be no doubt about their near relationship. Spines which may appear in a number of 2 — 6 are only found in 6 species, namely, P. magnifica, P. biciispis, P. tiiberosa, P. rectilineata, P. viiltur and P. Elleri. On the other hand, they are lacking in P. porosa, which is very nearly related to the two last-mentioned spe- cies. The aperture is provided as a rule with a more or less concave, more rarely straight or slightly convex, proximal margin and its form may be circular (P. iindata, P. magnifica), quadrangularly rounded (P. bisinnata) or more or less elongated semicircular (P. tiiberosa, P. ilorsiporosa etc.). Each lateral margin is sometimes more or less distinctly incurved (P. japonica, P. castanea). Whilst teeth are quite wanting in P. japonica, P. tiiberosa, P. rectilineata and P. clorsi- porosa, there is a single median tooth in P. castanea, two very small teeth medi- ally on the proximal margin in P. iindata and in all the other species a median tooth and two lateral teeth, the latter of which may also be of somewhat differ- ent form. In P. porosa and nearly related species, where they are situated far out to the sides, they resemble in form and position the hinge-teeth in many Smittina species, but they cannot be compared with these as they are placed outside the operculum. In P. bisinnata the three teeth have obviously only arisen by the formation of two incisions in the proximal margin of the aperture, and in this regard an undescribed form from Singapore is of interest, as the concave proximal margin of the aperture is in some zooecia quite entire, whilst others are provided with one or two incisions similar to those found in P. bisinnata.
The rosette-plates, which are present in fairly large to large numbers, are uniporous only in P. hiciispis, whilst in the other species examined by me they are provided with li — 10 pores.
Of the hitherto known species of this family only four are incrnsting (P. /)/- ciispis, P. Tlienardi, P. rectilineata, P. aincalifera), whilst the others occur in free, one-layered, laminate expansions, and it may be considered as a good fam- ily character that the basal wall in all these species is provided with pores, which otherwise appear only very exceptionally on the basal wall of free, one- layered colonies within the division Ascophora. Whilst these pores occur scat- tered over the whole of the basal wall in P. nnilata and P. japonica, in all the other species they appear in one or more, rarely (P. dorsiporosa) several pore- chambers, which are situated at the distal end of the basal wall. In the unde-
352
scribed form from Singapore just mentioned, which for the rest is most closely related to P. japonica, we find instead of the scattered pores in P. japonica such a distal pore-chamber in most of the zooecia, and this may sometimes attain a third of the whole length of the zoa>cium.
Petralia japonica Busk.
Lepralia japonica Busk, Challenger, Zoology, Vol. X, 1884, Part I,
Cheilostomata, p. 143, PI. XVII, fig. 5.
(PI. XVIll, figs. 5 a-b).
The zooecia quadrangularly or hexagonally tongue-shaped, covered by a yellowish brown membrane and provided both on the frontal and on the basal wall with numerous, scattered pores, between which there are larger and smaller tubercles. The pores of the frontal wall are however considerably larger and as a rule somewhat more numerous than those of the basal wall. The large, some- what elongated aperture, which is provided with a thick, but not very promin- ent peristome, has a slightly concave proximal margin, and each lateral margin is provided in its proximal half with a part projecting inwards, within which there is a stout hinge-tooth. The operculum, which is well-chitinized and dis- tinctly separated from the compensation-sac, has a stronger chitinized marginal ridge, which joins on to a muscular process almost medially on each lateral margin. The proximal margin however has only a continuation of this on each side. Each distal wall is provided with up to 16 and the distal half of each lateral wall with up to 8 multiporous, scattered rosette-plates with 4—7 pores.
The ocecia, which appear very seldom, have their basal half sunk into fairly deep pits, the base of which is formed by the cryi)tocyst, which is provided with pores, of the distal zooecium. Their frontal surface, which may be more or less strongly arched, is provided with numerous, densely placed, small pores.
Avicularia. On the one lateral margin of the aperture, in the neighbourhood of the inwardly projecting part, we somewhat rarely find a small, circular or oval avicularium, almost entirely immensed but with the point somewhat project- ing; its broadly rounded mandible is as a rule directed obliquely outwards and proximally, more rarely quite proximally.
Of this species I have examined some few colonies which occur in the form of one-layered, hollow expansions.
Formosa Channel, Lat. 23" 20' N., Long. 118" 30' E., 17 fathoms depth (Andrea).
353
Family Hippopodinidae n. f.
The somewhat thin-walled zocecia have no spines and are provided with scat- tered pores. The primary aperture has a concave proximal margin and the slightly chitinized operculum is surrounded by a more strongly chitinized marginal part. Hinge-teeth and a peristome may be present or absent. Uniporous or multiporous rosette-plates. An avicitlariiim may appear on the one or on both sides near the aperture. The nwcia, which are endoocecial yet project distinctly on the surface of the zooecia, consist of a membranous ectoocrcium and a calcareous endoooe- cium provided with scattered pores.
To this family belong the two genera Cheilopora and Hippopodina.
Cheilopora n. g. Lepralia Hincks, part.; Mucronella Hincks, part.; Hippoporina Nev., part. (PI. XXIV, fig. 4 a). The distal wall has no expansion partly separating the oa'cium from the zooe- cium ; multiporous rosette-plates; peristome present in the form of a lip-like pro- jection.
To this genus belong "Lepralia" sinccra Smitt, Hippoporina circuincincta Nev., ^Mucronella<^ praelucida Hincks, M. praelonga Hincks and 'Lep.' Griinaldi Jul.
Hippopodina n. g. Lepralia part.
The horizontal part of the distal wall is continued into an expansion which forms a partial partition between the occcium and the zooecium; uniporous ro- sette-plates; no peristome.
Hippopodina feegeensis Busk. Lepralia feegeensis Busk, Challenger, Zoology, Vol. X, 1884, Polyzoa,
part I, p. 144, PI. XX, fig. 9. Lepralia feegeensis Mac Gillivray, Proceed. R. Soc. Victoria (n. s.), Vol. in, (1890) 1891, p. 81, PI. X, figs. 1—3. (PI. XXIV, figs. 3 a-3 f).
The zocecia, which have a very small depth (distance between frontal and basal wall) are usually more or less regularly rectangular, fairly broad and thin-
23
354
walled, and the weakly arched IVontal wall is provided with small, round ]iores, as a rule densely placed, which may however be wanting on the part round the aperture. Each of them is more or less surrounded by a raised wall, which is always highest and most strongly developed about the proximal half of the pore and sometimes only distinctly developed round this. The aperture, the anter of which is surrounded by a slight, collar-shaped peristome, varies somewhat in form, as its poster may sometimes be considerably narrower than its anter and sometimes almost reach this in breadth. Opposite its proximal fifth to third it is provided on each side with a triangular projection, within which there is a stout conical hinge-tootii, and whilst the anter of the aperture approximates to the two-thirds of the circumference of a circle, its poster is only strongly arched at the sides and almost straight or slightly convex in the middle. The weakl}' cliitinized operculum is provided with a continuous marginal ridge. Each distal wall is provided inside its basal edge with ca. 10 and the distal half of each lateral wall with 5 — 8 uniporous rosette-plates.
The ooecia, which occupy the whole breadth of the zooecium, are as a rule longer than broad and their somewhat strongly arched frontal wall is provided with numerous, densely placed, larger and smaller, round or oval pores. The raised network surrounding the pores shows a more or less distinct, concentric striation, and along the middle of each ridge especially there is a narrow, raised line, so that each pore comes to lie at the bottom of a 4 — 6 sided, deepened area. The membranous ectoooecium shows a corresponding division into areas, separated from each other by yellowish, presumably cliitinized lines. The basal wall of the ooccium, which arises a little frontally to the basal wall of the zooecium, rises obliquely up towards the frontal wall and is provided with ca. 10 scattered, round pores. The frontal wall of the onccium projects a little beyond the frontal edge of the prolongation of the distal w-all, so that the egg coming from the zocrcial aperture will be easily led over into the ooecium.
Avicularia appear on a larger or smaller number of zod'cia to the number of one or two, which are usually placed distally to the ajjerlure, more rarely on the sides of this. They are triangular, but of very different length from differ- ent localities, and the longest of them have the mandible drawn out into a long, thin, terminal j)art. In them all the central third of the subo[)ercular area is covered by a dark, cliitinized, longitudinal belt, which is presumably a part of the covering membrane. These avicularia are fairly short on colonies from St. Thomas (from Pndodesiniis falcatiis) and the mandible is directed ol)li(|uelj' dis- tally and inwards. They are long and narrow on colonies from Singapore and
355
Ihey have here a similar position as on the specimen figured l)y Husk. On a colony taken from Manicina an-olata (without locality) the aviculai-ia have a similar form but are directed obliquely proximally and inwards.
The colonies form crusts on corals, on Tridacna sp. and on a sponge.
St. Thomas, Singapore (Schytt, S. Gad).
2;i*
LITERATURE
1. Barrois, Jules. Recherches sur I'embryo-
logie lies Bryozoaires. (Travaux de rinslitut do Zoologie, Lille, Fasc. I, 1877, 305 pp., 16 pis.). Also separate, Paris and Lille, 1877, 4to.
2. Busk, George. Catalogue of the Marine
Polj'zoa in the collection of the Brit- ish Museum. Cheilostomata, Part I, VIII 4- VI -f 54 pp., 68 pis. London 1852. , (Review of Part I in the Quarterly Journal of Microscopical Science, I, 1853, pp. 136-137.) Part H, VIII + 55- 120 pp., pis. 69—124. London, 1854.
3. — An account of the Polyzoa and Sertu-
tarian Zoophytes collected in the voy- age of the Rattlesnake on the coasts of Australia and the Louisiade Archi- pelago (John Mac Gillivray's Narrative of the Voyage of H. M. S. Rattlesnake, commanded by the late Captain Owen Stanley, during the years 1846—1850, Vol. I, 1852, pp. 343-402, pi. I).
4. — Zoophytology (Quarterly Journal of
Microscopical Science IV, 1856, p|). 176 — 179, pis. VII, VIII).
5. — Zoophytology (Quarterly Journal of
Microscopical Science, V, 1857, pp. 172— 174, pis. XV-XVI.
6. — Zoophytology (Quarterly Journal of
Microscopical Science (n. s.), I, 1861, pp. 153-156, pis. XXXIV, XXXV.
7. Busk, George. A Monograph of the
Fossil Polyzoa of the Crag. (Publica- tions of the Palpeontograjihical Society, London, 1859. XIV, 136 pp., 22 pis.).
8. — Report on the Polyzoa collected by
H. M. S. Challenger, during the years 1873—1876 (Report on the Scientific Results of the Voyage of H. M. S. Chal- lenger — Zoology.) Part I, The Cheil- ostomata, Vol. X, part XXX, 1884, pp. I-XXIV, 1-216, pis. I-XXXVI.
9. Calvet, Louis. Contributions a I'Histoire
Naturelle des Bryozoaires Ectojjroctes Marins, pp. 488, XIII pis. et 55 figures dans le texte. Montpellier et Paris, 1900.
10. — Bryozoaires Marins de la Region de
Cette, pp. 103, III pis. Montpellier 1902.
11. — Bryozoen(HamburgerMagalhaensische
Samnielreisc), pp. 45, III Tafel, Ham- burg 1904.
11a. Canu, M. F. Revision des Bryozoaires du Cretace figures par d'Orbigny. Deuxieme Partie. — Cheilostomata. (Bulletin Soc. G6ol. de France [3. s]. XXVIII. 1900 pp., 334-403, pis. IV-VII).
lib. — Les Bryozoaires du Patagonien. Kchelle des Bryozoaires pour les Terrains ter- tiaires (Memoires de la Society Oeo- logique de France. Paleontologie,
358
'lome XII. Fuse. III. Mciiioirc No. 33. 1904, pp. 5-30, pis. IV-VIII. 11 c. — Iconofiraphie des Bryozoiiires fossiles (ic r.\rj<enliiu' (.Vnalcs del Miiseo Na- cional de Buenos Aires, Tonio XVII, [StT. [i«, t. \|, |). 24.-) a 311, pi. I-XIII, 1908).
12. Ellis, John. Essay towards a naliiia! his-
tory of the corallines and other marine productions of the like kind commonly found on the coasts of (ireat Britain and Ireland. Lonilon, I".'),'), 120 pp., 39 pis.
13. Ellis, John, and Solander, Daniel. The
natural history of many curious and uncommon Zoophytes, collected etc., by the late .lohn Ellis, systematically arranj^ed and described by Daniel Solander. London, 1780. 4to, 206 pp., G3 pis.
11. Fabricius, Otho. Fauna groenhmdica. llafniae et Lipsiae, 1780.
13. Goldstein, J. R. Y. .\ new species of I'olyzoa [(".atenicella i)onderosa] (Quar- terly Journal of the Microscopical Society of Victoria, 1, 1880, p. 63, pl.V. 1-3).
16. — Some new S|)ecies of Hryo/.oa from
the Marion I.slands, with notes on Bi- cellaria grandis. (Transactions of the Royal Society of Victoria, XVIII, 1882, pp., 30—16, i)ls. I, II). 16 a. Gregory, J. W. On the British I'ake- ogene Bryozoa. (Trans. Zool. Soc. of London, 1893, vol. XIIL part VI, No. 1, pp. 219-279, |.ls. XXIX-XXXII).
17. Harmer, Sidney. F. \ revision of the
genus Stegano|)orella (Quarterly Jour- nal of Microscopical Science |n. s.|, 13, ft. 2, 19(10, pp. 225-297, pis. 12, 13).
18. — On the Structure and Classification
of the {^hcilostomatous Polyzoa (Pro- ceedings of the C.andjridge Philoso- phical Society, Vol. XI. Pt. 1, pp. 11—17, 1900).
19. Harmer, Sidney. F. On the Morphology
of the (".heilostomata (Quarterly Jour- nal of Microscopical Science, |n. s.|, 46, Pt. 2, 1903, pi). 2()3-3.'')0, pis. 15-18).
20. Haswell, William A. On sonic Polyzoa
from the (jiu'cnsland coast. (Proceed- ings of the Linnean .Society of New South Wales, V, 1880, |)p. .33-40, pis. I-Ill).
21. Heller, Camil. Die Biyozoen des Adria-
tischen Meeres (Verhandlungen der k. k. zoologisch. botanischcn Gcsell- schaft in Wien, XVII, 1867, pp. 77—136, pis, 1-Vl).
22. Hincks, Thomas. A History of the Brit-
ish Marine Polyzoa. 2 vols. London. 1880. Vol. I, Text CXLI + (iOl j)]).. Vol. II, Plates I-LXXXIII.
23. — Contributions towards a general his-
tory of the marine Polyzoa. I Madeiran Polyzoa. II Foreign Mcmbraniporina. (Annals Nat. Hist., 1880, [5 s.]. Vol. VI, pp. 69—92, pis. IX— XI). Contributions etc. (continued). II Foreign Mcmbrani- porina (coutimicd). Ill Foreign Chcilo- stomata (Miscellaneous) (.\nnals Nat. Hist., 1880, (o S.J, Vol. VI, pp. 376-384, ])ls. XVI, XVII).
24. — Contributions ...(continued). IV For-
eign Memi)raniporina (second series). V Foreign ("^heilostomata (Miscellaneous ). (Annals Nat. Hist., 1881, [5 .s.|. Vol. VII, 1)1). 147-161, pis. VIII-X).
25. — Contributions . . . (continued) VI. Poly-
zoa from Bass'sStraits. VII Foreign Mcm- braniporina (third series). VIII Foreign ('.heilostomata (Miscellaneous) (.\nnals Nat. Hist., 1881, |.') s.|. Vol. VIII, pp. 1-14, 122-136, pis. I-V).
26. — Contributions ... (continued). IX. For-
eign Cheilostoniata (Miscellaneous). Annals Nat. Hist., 1882, |5 s.|. Vol. IX, pp. 116—127, pi. V).
27. — Contributions ... (continued). X. For-
eign (^heilostomata (Miscellaneous).
359
28. -
29.
30.
31.
32.
33.
34.
35.
36.
37. -
38.
(Annals Nat. Hist., 1882, (5 s.]. Vol. X, 1)]). 160-170, pis. VII, VIII. Contributions . . . (continued). XI. For- eign Cheilostoniata (Australia and New Zealand). Annals Nat. Hist., 188.3, (5 s.], Vol. XI, pp. 193-202. pis. VI, VII). Contributions . . . (continued). XIII. Polyzoa from Victoria (continued). Annals Nat. Hist., 1884, [5 s.], Vol. XIV, pp. 276-285, pis. VIII, IX). Contribution.s . . . (continued). XIV. Polyzoa from New Zealand and Au- stralia. XV. Cheilostoniata— Miscellane- ous. (Annals Nat. Hist., 1885, |5 s.]. Vol. XV, pp. 244—257, pis. VII— IX). Contributions . . . (continued). XV. South .\frican and other Polyzoa. (An- nals Nat. Hist., 1891, |6 s.], Vol. VII, p|). 285-298, ])ls. VI, VIl). Heport on the Polyzoa of the QHieen Charlotte Islands. (Annals Nat. Hist., 1882, [5 s.]. Vol. X, |)p. 459—471, pis. XIX, XX).
Report on the Polyzoa of the Queen Charlotte Islands (continued). (Annals Nat. Hist., 1883, [5 s.]. Vol. XI, pp. 442-551, pis. XVII, XVIII). Report on the Polyzoa of the Queen Charlotte Islands (continued). (Annals Nat. Hist., 1884, |5 s.], Vol. XIII, pp. 49-58, pis. Ill, IV, pp. 203-215, pi. IX. The Polyzoa of the Adriatic: A sup- plement to Professor Heller's wDie Bryozoen des Adriatischen Meeres, 1867 (Annals Nat. Hist., 1886, [5 s.], Vol. XVII, pp. 254-271, pis. IX, X). The Polyzoa of the Adriatic (contin- ued). (Annals Nat. Hist., 1887, |5 s.|, Vol. XIX, pp. 302-316, pi. IX). Note on the ovicells of the Cheilos- tomatous Polyzoa. (Quart. Journ. Micr. Science, [n. s.], I, 1861, pp. 278-281). Contributions to the history of the Polyroa. (Quart. .lourn. Micr. Science, |n. s.j, XIII, 1873, pp. 16-36, pi. 11).
38b.
39
38 a. Hincks, Thomas. Contributions . . . 1880—91, Appendix (Annals Nat. Hist., 1891, [6 s.]. Vol. VIII, pp. 86-93, 169- 176, 473-480, 327—334.
Marine Polyzoa: Contributions to- wards a general history. 1880—91. The above ))Contributions« reprinted and edited as a separate book to which is added an index by the author. Huxley, Thomas H. Note on the repro- ductive organs of the Cheilostome Polyzoa. (Quarterly Journal of Micro- scopical Science, IV, 1856, pp. 191 192.
40. Jelly, E. C. A synonymic catalogue of
the recent marine Bryozoa including fossil synonyms. London, 1889, XV -\- 322 pp.'
41. Joliet, Lucien. (Contributions a I'histoire
naturelle des Bryozoaires des cotes de France (Archives de Zoologie cx- perimentale et generale, VI, 1877, pp. 193-304, pis. VI-XIII). 41 a. Johnston, George. A History of the Brit- ish Zoophytes. London 1838 and 1817.
42. Jullien, Jules. Note sur une nouvelle di-
vision des Bryzoaires (Cheilostomiens. (Bull. Soc. Zoolog. de France, VI, 1881, pp. 271-285).
43. — Dragages du Travailleur. Bryozoaires ;
especes draguees dans I'ocean Atlan- tique en 1881 (Bull. Soc. Zoolog. de France, VII, 1882, pp. 497-.529, pis. XIII-XVII).
44. — Les Costulidees, nouvelle famille de
Bryozoaires. (Bull. Soc. Zoolog. de France, XI, 1886, jip. 601-620, pis. XVII-XX).
Mission scientilit|ue du Cap llorn, 1882—83. VI. Zoologie, 1888. Bryozo- aires, 92 pp., pis. 1— XV. Sur la sortie et la rentree du Poly- pidc dans les zoa'cies chez les Bryo- zoaires cheilostomiens mono<lcrmies (Bull. Soc. Zoologicpie de France, XIII, 1888, pp. 67-68).
45.
45 a.
360
46. Julllen, Jules ct Calvet, Louis. Hisul-
tats dcs Canipat^ncs scicntifiqiu's ilii Prince de Monaco. Fascicule. XXIII. Bryozoaire.s provcnanl des canipagne.s de I'Hirondelle (1886—1888), Monaco, 1903. 188 pp. pLs. I-XVIIl.
47. Kirkpatrick, R. On the Poly/.oa of Mau-
ritius (Annals Nat. Hist. [6|, 1, 1888, 72-85, pis. VII-X).
48. — Report upon the Hydrozoa and Poly-
zoa collected by P. W. Bassctt-Smith, Esg., surgeon R. N., during the survey of the Tizard and Macclesfield banks, in the China Sea, by H. M. S. Ramb- ler, Commander W. U. Moore (Annals Nat. Hist. (6J. V. 1890 pp. 11-24. pis.
m-v).
49. — Report on the zoological collections
made in Torres Strait by Prof. A. C. Haddon, 1888, 1889. Hydroida and Polyzoa. (Scientific Proceedings of the Royal Dublin Society [n. s.], VI, 1888— 90, pp. 603—626, pis. XIV— XVII).
49. a — Description of a new Species of
Retepora from Port Western. Victoria (Annals Nat. Hist. 1888. |G. s.], Vol. 11, p. 269).
50. Koren F., and Danielsen, D. C. Beskri-
velse over Kinetoskias smittii og arborescens. (Fauna littoralis Nor- vegiac. III. 1877).
51. Lamarck Jean, Baptiste de. Histoire na-
turelle des animaux sans vertebres. Paris 1836, Ed. 2, by G. P. Deshayes et H. Milne-Edwards. T. II.
52. Lamouroux, J. V. F. Histoire des Poly-
piers Coralligenes flexibles, vulgaire- ment nomni^s Zoophytes. Caen 1816.
.53. Levinsen, G. M. R. Bryozocr fra Kara- llavct (Dijmphna-Togtels zoologisk- botaniske Udbyttc, Kjobenhavn, 1886, pp. .305—328, pis. XXVI, XXVII).
54. — Polvzoa. Del vidcnskabelige I'dbvtte
56.
.58.
,58.
59.
60.
61.
62.
63.
af Kanonbaailcn
nllauchus Togter,
1883—86, Kjobenhavn, 1891, llo, pp. 243-306, 3. pis. Levinsen, G. IW. R. Mosdyr. Zoologia Danica. Ilclte 9, 1894, pp. 1—105, pis. I — IX, Kjobenhavn.
— Studies on Bryozoa (Vidcnskabelige Meddelelser fra den natin-historiske Forening i Kjobenhavn, 1892, pp. 1— 31.
Linnaeus, Carolus. Systema Naturae. Ed. 12, Holmiae. 1767. Tome 1, pars II. Z(.oi)liyta, pp. 1287-1.301.
Lorenz, Ludwig von. Bryozoen von Jan Mayen. (Die Internationale Polarfor- schung 1SS2- 83. Die Oestcrreicliische Polarstation Jan Mayen, Band 111, 1886, pp. 83-100, pi. VII). a Marsson, Th. Die Bryozoen dcr wcissen Schrcibkreide der Inscl Riigen. (I'alsc- ontologische Abhandlungcn, heraus- gegeben von W. Dames und E. Kayser, Viertcr Band, Heft 1, Berlin 1887, 112 pp., 10 pis.
Mac GilHvray, P. H. On some- new Aus- tralian Polyzoa (Trans. Pliilos. In- stitute of Victoria, IV, 18,59, part 1, pp. 97—98, pi. 1).
— Notes on the Cheilostomatous Polyzoa of Victoria . . . (Trans. Philo.s. Insti- tute of Victoria, IV, (1859), 1860, part 1, pp. 159-168, pi. 2,3).
— Descriptions of some new genera and species of Australian Polyzoa; to which is added a list of species found in Victoria (Trans, and Proceed. R. Soc. of Victoria, Part II, IX (1868), 1869, pp. 126-148).
— On two new genera of Polyzoa (Trans, and Proceed. H. Soc. of Victoria, XVII, (1880), 1881, pp. 15-18, 1 p!.).
On some new sjiecies of (;atenicel]a and Diclyopora; and on Urccolipora, a new genus of Polyzoa (Trans, and Proceed. R. Soc. of Victoria, XVII. (1880), 18S1. pp. 84—87, 1 pi.).
361
64. Mac GilUvray, P. H. Descriptions of
new, or little known Polyzoa. Part I, {Trans, and Proceed. R. Soc. ol Victoria, XVIII (1881), 1882 [n. s.J, pp. 115-121, 1 pi.).
65. — Descriptions of new . . . (continued).
Part II. (Trans, and Proceed. R. Soc. of Victoria, XIX, (1882), 1883, pp. 130-138, pis. I-III).
66. — Descriptions of new . . . (continued).
Part III. Trans, and Proceed. R. Soc. of Victoria, XIX (1882), 1883, pp. 191—195, pis. I, II).
67. — Descriptions of new . . . (continued).
Part VII, (Trans, and Proceed. R. Soc. of Victoria, XXI (1884), 1885, pp. 92-99, pis. I-III).
68. — Descriptions of new . . . (continued).
Part VIII. (Trans, and Proceed. R. Soc. of Victoria, XXI, (1884), 1885, pp. 106-119, pis. I— V).
69. — Descriptions of new . . . (continued).
Part IX. (Trans, and Proceed. R. Soc. of Victoria, XXII, (1885), 1886, pp. 128-139, pis. I-III).
70. — Descriptions of new . . . (continued).
Part X. (Trans, and Proceed. R. Soc. of Victoria, XXIII, (1886), 1887, pp. 34-38, pis. I-II).
71. — Descriptions of new . . . (continued).
Part XI. Trans, and Proceed. R. Soc. of Victoria, XXIII, (1886), 1887, |)p. 64-72, pis. I-III).
72. — Descriptions of new . . . (continued).
Part XII. (Trans, and Proceed. R. Soc. of Victoria, XXIII, (1886), 1887, pp. 179-186, pis. I-III).
73. — Descriptions of new . . . (continued).
Part XIV, (Proceed. R. Soc. of Victoria, |n. s.]. Vol. Ill (1890), 1891, pp. 77-83, pis. IX. X).
74. — Polyozoa in Mc Coy's Prodomus of
the Zoology of Victoria. 2 vols. Mel- bourne. Vol 1, Decades I-X, 1879—
1885. Vol II, Decades XI-XX 1885— 1890.
75. Mac Cillivray, P. H. A catalogue of the
marine Polyzoa of Victoria. (Trans. and Proceed. R. Soc. of Victoria, XXIII (1886), 1887, pp. 187-224).
76. — A Monograph of the Tertiary Polyzoa
of Victoria [completed by T. S. Hall and W. Baldwin Spencer] (Transact. R. Soc. of Victoria, IV, 1895, pp. 1— 166, pis. I-XXII).
77. Milne-Edwards, Henri. Recherches ana-
tomiqucs, physiologiques et zoologi- ques sur les Eschares. (Annates d. Sciences Naturelles, Zoologie, [2|. VI 1836. pp. 5-53, pis. I-V).
77. a Neviani, Antonio, .\ppunti sui Briozoi
(lei Mediterraneo. Nota Prima. (Bollet- tino della Societa Romana per gli Studi Zoologici, VII 1898, pp. 1C3-](;,S, (! figs).
78. Nickles John M. and Bassler, Ray S.
A Synopsis ot American fossil Rryo- zoa, Washington 1900. (Contains a most complete list of papers treating of Bryozoa; pp. 469—663).
79. Nitsche, Hinrich. Beitnige zur Kenntniss
(lei- Bryozoen. 1 Beobachtungen iiber die Kntwickelungsgeschichte einiger chilostonien Bryozoen (Zeitschrift f. wissensch. Zoologie, XX, 1869, pp. 1— 13, pi. 1).
80. — Beitriige zur Kenntniss der Bryozoen.
III. Ueber die .\natomie und Kntwicke- lungsgeschichte von Flustra membra- nacea (Zeitschrift fiir wissenschaft- liche Zoologie, XXI, 1871, pp. 416— 470. pis. XXV-XXVII).
80. a Norman, Alfred Merle. Notes on some
rare British Polyzoa, with descriptions of new species. (Quarterly Journal of Micros. Science |n. s.] VIII 1808, pp. 212-222, pis. V-VII).
81. — x\ Month on the Trondhjem Fjord.
Polyzoa (Annals Nat. Hist., 1893 [6. s.]. Vol. XII, pp. 446-452, pi. XIX).
362
82. Norman, Alfred Merle. A Month on the
Trondhjeni Fjord. Polyzoa (continued). (Annals Nat. Hist., 1894, (0. s.], Vol. XIII, pp. 112-i;i;i, pl.s. V, VII).
<S;5. — Notes on the Natural Ili.story of cast Finmark, Polyzoa. (Annals Nat. Hist. l!)0;i, |7. .s.|, Vol. XI, pp. r)r)7— 508, pi. XIII).
84. — Notes on the Natural History of east Finmark, Polyzoa (continued). (Annals Nat. Hist. l<)0;i, |7. s.|, Nol. Xll, pp. 87-128, pis. Vlll, IX).
84. a — The Polyzoa of Madeira and neigh- bouring Islands (Journ. Linnean See, Zoology, XXX, 1909, pp. 273—314, pis. 33—42).
84. 1) Nordgaard, O. Systcmatisk Fortcgnclse over de i Norge hidtil observcredc arter af marine polyzoa. I. Cheilosto- mata. (Bergens Museums Aarbog 1894 — 95, Nr. II., 189(); pag. 3-34, PI. I-II).
84. c — Bryozoen von dem norvegischen Fi- schereidampfcr uMichacl Sars<i in den Jahrcn 1900—1904 gesaninielt (Bergens Museums Aarbog 1907, Nr. 2, pag. 3— 20, 1 pi.).
83. Novak, Ottamar. Beitrag zur Kenntniss
der Bryozoen der bohmischen Kreide- bildung. (Denkschriften d. math.-nat. Classe der k. Akademie d. Wissen- schaften, Wien, XXXVII, 1877, p]). 79— I2(i, ])ls. 1— X). <). Orbigny, Alcide de. Paleonlologie Iran- caise. Dcscrii)tions des animaux in- vertebrcs. Terrain Crctac(^. Tome cin- t|uiemc. Bryozoalres. Paris, 1850—1852. Text, 1192 i)p.. Atlas, pis. COO— 800.
7. Ortmann, Arnold E. Die japanische
Hryozoen-Fnuna. (Archiv f Naturge- schichte, 1890, 5(). .lahrg., 1. Band; pp. 1-74.
8. Ostroumoif, Alexis. Bcniar(|ues relatives
aux recherches de Mr. Vigelius sur les Bryozoalres. (Zoologischer \n- zeiger, VIII, 1885, pp. 290—291;.
89. Ostroumoff, Alexis, llxtrait de Tocuvre
sur la morphologic des Bryozoalres marines (Zoologischer Anzcigcr, VIII, 1885, pp. .577— .579).
90. — Die Bryozoen der Buclil \on .Sebasto-
pol. Vollslandigcre Ausgabe mil cincni ganr neuen 'I'lu'ile idjcr die Morpho- logie der Bryozoen. (Proceedings of the Society of Naturalists in Ka.san, XVI, Part II, 188(), 124 pp., 5 i)ls. (Bus- sian Text).
91. Pallas, Pierre Simon. l\lcnchus Zoophj'-
loriuii. La llaye, 1701).
92. Pergens, Ed. I'ntcrsuchungcn an Sce-
bryozocn. (Zoologischer Anzcigcr, XII 1889. pp. .504-510, 52r)-,533).
93. — B6vision des Bryozoalres du Cretaee
figures par d'Orblgny. (Memolres de la Societe Beige, dc Geologic, de Pale- onlologie ct d'llydrologie, Bruxcllcs, 111, 1889. pp. 305-400, pis. X-XIII).
94. Reichert, K. B. Vcrgleichcnde anato-
mlsche Untersuchungcn iiber Zoobo- tryon pellucidus (Fhrenbcrg). (Ab- handhmgen der koniglichcn Akademie der Wissenschalfen zu Berlin, II, 1870, pp. 2.33-338. pis. I— VI).
95. Reid, John. Anatomical and physiolo-
gical observations on some Zoophytes. (Annals Nat. Hist, [l], XVI, 1845, pp. 385-400, pl. XII). 9(). RepiachofF, Wassilij. Zui- f'ntwicke- lungsgcschichte dcrl'cndi'a zostcricola. (Zeitschr. 1'. wissensch. Zoologic, XXV, 1875, pp. 129-112, pis. VII— IX).
97. Sars, George Ossian. On some remark-
able forms of animal life from the great deeps of the Noi-\vcgi;m coast. (Fniversity ])rogram for the (irsl IimII' year 1869, Christianla, 1872, Ito, 82 pp., 6 pis.
98. Savigny, Jules Cesar. I)i'scri|)ti<)n dc
rivgypte. Hisloire nalurcllc, Phmchcs. Tome deuxicme. Polypes, ([jlates only].
363
Explication sommairc par V. Andouin in Tome premier, ])p. 225—244. 1826.
99. Smitt, Fritz Adam. F\ritisk fortcckninj^ ofvtT Skandinaviens Hal'.sbryozoer. (Ofversigtat'Kongl.Vetenskaps-Akade- miens Forhandlingar, XXIV, 1807, Nr. 5, pp. 279—429, pis. XVI— XX).
99. a — Bryozoa marina in regionibusarcticis et borealibus vivcntia (Otversigt af Kongl. Svcnska Vetenskaps - Akade- niiens Forhandlingar, 1867, No. 6, pp. 443-487).
100. — Kritisk forteckning ot'vcr Skandina-
viens Hafsbryozoer. (Ol'vcrsigt af ■ Kongl. Vetenskaps-Akademiens For- handlingar, XXIV, 1876, Bihang, pp. .3-230, pis. XXIV-XXVII).
101. — Kritisk iorteckning ofver Skandina-
viens Hafsbryozoer (Ofversigt af Kongl. Vetenskaps-Akademiens For- handlingar, XXVIlI, 1871, No. 9, pp. 1115—1134, pis. XX, XXI).
102. — Floridan Bryozoa, collected by Count
L. F. de Pourlales, Part 1 (Kongl. SvenskaVetenskaps-AkademiensHand- lingar, X, 1872, No. 11, pp. 1-20, pis. 1-V).
103. — Floridan Bryozoa . . ., Part II (Kongl.
SvenskaVelenskaps-.\kademiensHand- lingar, XI, 1873, No. 4, pp. 1—83, pis. I-XIII).
103. a — La Filiation des Especes dWnimaux.
(("ompte-rendu 3nie Congres Intern. Zool.). Leydcn (1895), 1896, p. 235.
104. Thompson, Wyville T. C. On new ge-
nera and sjjecies of Polyzoa in the collection of W. H. Harvey. (Natural History Review, V, 1858, pp. 134— 147, pis. X— XIll). (Proceeding of the Dublin University Zoological and Botanical Association, Vol. I, Part 1, 1858, pp. 77-93, pis. V— IX).
105. Vigelius, W.J. Die Bryozoen gesammclt
widirend der dritten und vierten Polarfahrt des Willeiii Barents, in
den Jahren 1880 ii. 1881 (Bijdragen tot de Dierkunde, Amsterdam, XI, 1881. 104 pp., 8 pis.). 106. Waters, Arthur William. Chiloslomatous Bryozoa from Aldinga and the River- Murray Cliffs, South Australia (Quar- terly Journal Geol. Soc. of London, XLI, 1885, pp. 279-310, pi. VII).
106. a — On the use of the Avicularian Mand-
ible in the determination of the Chiloslomatous Bryozoa (Journ. B. Micr. Soc, 1885, Ser. II, vol. V, pp. 774-779. pi. XIV).
107. — Bryozoa from New South Wales,
North Australia, etc. (Annals Nat. Hist. [5], XX, 1887, pp. 81—95, pi. IV; pp. 181-203. Ills. V, VI, pp. 253-265, pi. VII).
107. a — On Tertiary Chiloslomatous Bryozoa
from New Zealand (Quarterly .lourn. C.eolog. Soc, 1887, XLIII, p. 40—72, 1)1. VI-VIII). — Bryozoa from New South Wales. Annals Nat. IIi.st. [6], IV 1889. pp. 1 — 24. pis. I-III. a - On Chiloslomatous Characters in Melicertilidae and other F'ossil Bryo- zoa (Annals Nat. Hist. [6], VIII, 1891, pp. 48—51, pi. VI). 108.1) — Observations on the Cland-like Bo- dies in the Bryozoa (Journ. Linnean Soc. XXIV 1892, pp. 272-278, pi. XIX.
108. c — On Meditenanean and New-Zealand
Reteporiv and a fenestrate Bryozoa (Journ. Linnean Soc, Zoology, Vol. XXV, 1894, pp. 255-271, pis. VI— VII.
109. — Interzoa'cial conmiunication in Flu-
stridae and notes on Fluslra. (.lourn. R. Micros. Soc. 1896, pp. 279-292, pis. VII, VIII).
110. — Supplementary re])orl on the Polyzoa,
collected by II. M. S. Challenger during the years 1873—1876. (Report on the scientific results of the voyage of
108.
108.
364
H. M. S. Chullemjcr, Zoology, XXXI, Pari LXXIX, London, 1889, pp. 1—41, pis. I-III).
111. Waters, Arthur William. Notes on the
Bryozoa IVoiii Hapallo and other Mediterranean localities, chiefly Cel- lulariidae. (Joiirn. Linn. Soc, Zoology XXVI, 1890, pp. 1-21, pis. I, II).
112. — Observations on Membraniporidae.
(Journ. Linn. Soc, Zoology, XXVI, 1898, pp. 654—693, pis. XLVII— XLIX).
113. — Bryozoa from Madeira. (Journ. R.
Micr. Soc, 1899, pp. 6—16, pi. III).
114. — Bryozoa from Franz -Josef Land,
collected by the Jackson-Harmsworth Expedition 1890—97. (Journ. Linn. Soc, Zoology, XXVIII, 1900, pp. 43— 105, pis. V— XII).
115. Waters, Arthur William. Bryozoa. (Ex-
pedition Antarctique Beige, Anvers 1904, lO,'^ pp., pis. I-IX).
116. — Tubucellaria: its Species and Ovicells.
(Journ. Linn. Soc, Zoology, XXX, 1907, pp. 126-133, pis. XV, XVI). lie. a — Reports on the Marine Biology of the Sudanese Red Sea, from Collec- tions made by Cyril Crossland, M. A., B. Sc, F. Z. S.; together with Collec- tions made in the Red Sea by Dr. R. Martmeyer — XII. The Bryozoa. (Journ. Linnean Soc, Zoology, vol. XXXI, 1909, pp. 123—181, pis. X—
xvni).
117. Whitlegge, T. Notes on some Australian
Polyzoa (Proceed. Linnean Soc. ot New South Wales [2], II, 1887, pj). 337—347). Annals Nat. Hist. [6J 1, 1888, pp. 13-22).
Plate I.
Plate I.
Ki};. 1 :i. Two ooecia of Flustra papi/racea Ellis ami Sol. The proximal ciul of the opercular muscle of the (xicium is seen between the zod'cial o])erculum and the otceium. X 23.
— 2 a. A loiifiitiidinal section throiif(h an oieeium
of /'/iis/ra nwrnhraitacco-truncald Smitt. A low cry])t()cyst belt is seen between the o(ecium and the coverin)^ membrane (the ectoo(icium). The membranous wall separating the ziKccium from the ixvcium is incorrectly indicated as the muscle of the oa-cial operculum. I'his muscle is not seen in the figure. X 40.
— 2 b. An ocecium of the same species fmm the
frontal aspect. The pro.ximal part of the od'cium is covered with a cryptocyst belt, and the pro.ximal ends of the muscles of the ooecial operculum are .seen between this belt and the zooecial operculum. X 40.
— 3 a. An oiucium of Flustra Barlcei Busk. The
same parts as in I-"ig. 2 b arc seen here. X 40.
— 4 a. Flustra (Spirataria flnslroides vHincks , with
od'cia. The two pro.ximal oacia arc com- pletely covered by the cryptocyst belt, whilst the four distal show the latter in difl'erent degrees of development. X 40.
— 4 b. An ocecium of tlie same species, enclosed in
an avicularium. X 40.
— 4 c. Two od'cia of the same species; lateral view.
X 40.
— 5 a. Longitudinal section through two oa'cia of
Flustra securifrnns (Pallas\ X 40. The muscle of the 0(ccial operculum (m. ov.) is seen in the angle between the oa'cial oper- culum and its inner membranous continua- tion, d. w. cryptocyst process.
— a b. An od'cium of the same species from the
frontal surface. The ocecial operculum, the pro.ximal end of its muscle and the two cryptocyst processes id. w.) are seen between the oa'cium and the zooecial operculum. X 40.
— 5 c. The distal wall — from the distal end — of
a zod'cium with oa'cium. The oiecial muscle and the two crvptocvst processes are seen. X 40.
— () a. A zooecium with (xecium of Flustra {Kcli-
Pustra) cribrifonnis i Husk . X 40.
— () b. The same species, from the basal surface.
The uncalcified longitudinal belt is more dilated at the distal end of the three zooc- cia with oreeia. X 23.
— 7 a. Flustra Retiflustra; Schonaui n sj).. with
a pear-shaped avicularium. The cryptocyst of the zoa'cia shows lines of growth. X 40.
— 7 b. A young zooecium with ouccium. of the same
species. X 40.
— 7 c. An older zotrcium with oncium, of the same
species. The proximal part of the ofccium is covered by a cryptocyst belt. X 40.
— 7 d. Tlie same species from the basal surface.
X 23.
— 8 a. Two egg-shaped ooecia of Flustra (Flustra)
foliacea L. X 40.
— 8 b. Two oiL-cia of the same species, lateral view,
d. w. the distal wall. X 40.
I'ig. 0 a \ zoirciuni with orecium of Flustra (Spiral- <iri(i denliculatii Busk. The oiecium is en- closed in an avicularium. X 40.
— 10 a. F'arciniinaria uncinata Hincks, wirli od'-
cium. X 23.
— 10b. The .same species. The ooeciuni and the
surrounding kenozonccium. lateial \ iew X 23.
— 10 c. The same species. The 0(eciuni partly from
the basal surface. X 23.
— 10 d. The same species. A longitudinal section
through the gouozoiecium, the ocrcium and the surrounding keuozoa?cium. The distal wall d. w.) between the gonozooccium and the kenozotecium is seen. m. ov. the meiu- branous wall separating the zo(ecium from the oiecium. X 23.
— 10 e. A longitudinal section through the same
parts but parallel to the frontal wall of the gonozocecium. The angular distal wall between the gouozoa-cium and the keno- zocecium is seen. X 40.
— 11a. Nellia ajipcndiculata (Hincks!. The two
proximal zoa'cia with ocecia. X 40.
— lib. The same .species. A longitudinal section
through two zocccia with ocecia; only the endi)o(xcium is seen whilst the likewi.se calcilied ectooiecium has been overlooked, m. ov. the membranous wall between the zo<ecium and the oiecium. X 40.
— 12 a. Two zo(ccia with oiecia of Columnaria
borealis n. sp. On each side of the ooccium In its distal half is seen a cryptocyst olate. X 17.
— 121). The same species. The membranous ecto-
oa'cium and the triangular cryptocyst plate (ekto) of the oiecium are seen. X 17.
— 12 c. Some zotveia of the same species, the mem-
branous parts of which have been removed. The lateral walls and the distal wall {d. w.) with rosette-plates in addition to the cryp- tocvst plate of the ooecium (ekto) are seen. X '23.
— 12 d. A longitudinal section through a zo(ecium
with (xecium. The membranous ectoocecium, the cryptocyst plate eklo' of the od'cium and the membranous wall between the zoa'cium and the oiecium (m. ov.) are seen. X 23.
— 13 a. Xellia tenella (Lam.). All the zocccia with
o(ecia. X 100.
— 13 b. The same species. The two proximal zooe-
eia to the left without ofccia. An avicul- arium chambci' is seen through one of the lateral walls of the middlemost zocccium. X 40.
— 13 c. A zoci'cium with occcium. The ectoocecium
shows an uncalcified transverse belt. X 75.
— 13d. A longitudinal section through an ocecium
of the same species. The membranous parts are not seen and the calcified ectooiecium is by a mistake not separated from the endocxrcium. X 40.
— 13 e. An avicularium of the same species with
pit for the insertion of the radical fibre. X 200.
a. M./t /. cr'irixc ii . liriyo ;or/ .
PI./
nA
/ /-Ou/n, /i.ifiyr-arrt, JW .' /?./«^////./vw«r,v/ /r„»r„/» S,„,// jFI /irir/,et /J,u/.- ',.f7 n„.s/r«l,U.^ //,,>c/.:k .i./y.ifnirrrrofls/W/.
fi.ncr,/>r,fnr,„t.K /iiiH- 7F/Sr/,oruliii //.>// S /■'//},/,, ir,;i /■. .9. /'/.rUyi/frllf^i/n ./JusA'. /OJnrririll rutrla „/ir,n„/n //inrAx.
// Firrr iififirndiiit/ri/ti //uiAs /,'' /'rrrc. /imed/ix n xfi >■'! /-hrr Uri<//n /.rrrii
Plate II,
368
Plate II.
Fig. 1 a.
— 1 b.
— 2 a.
— 21).
— .■) a.
— .il).
— 3 c.
— 4 a.
— 4 1)
— 6 a.
— 7 a.
— 71).
— 7cl.
— 7e.
Mcnipea cnjslallina (Gray). Two occcia sur- rounded by kciiozooscia are seen in the pro.ximal intcrnodc. X 40. The same species. A longitudinal section through a gonozocecium, an oa'cium and a surrounding kenozoojciuni. X .')5. A portion of Menipea cyallms Wyv. Th., from the basal surface. X 40. .•\ longitudinal section through a zo(Tcium of the same species. The distal wall with rosette-plates is .seen. X 40. A portion of Menipea Biiski Wyv. Tli The distal zod'cium covers an endozoiecial oie- cium, the distal part of which is covered by a granular cryptocyst. X 40. A portion of the same species from the basal surface. X 40.
A longitudinal section through a zotEcium of the same species with oo-cium. X 5.'). .\ jjortion of Menipea cervieornis Mac (lill.). The distal zoa'cium covers an endozooecial oa'cium, the distal part of which is covered by a granular cryptocyst. X 40. .\ longitudinal section through a zocecium of the same species with oa'cium. X 55. -f. A series of dcvclo])mental stages of the occcium o( Scnpocellaria scabra y. lien.). The oblique frontal part of the distal wall is seen proximally to the developing ott- cium. X .'i.'i.
C.aberea F.llisi (Flem.). The proximal zo(K- cium with rudiment of oa'cium. X 40. Menipea rohorala (Hincks), with oa-cia. The proximal jjart of the ectooa'cium is uncalci- iied whereby a triangular area is formed. The horizontal part of the distal wall (d. w.) is visible. X 40.
The same species without ooecia. Three of the zoa'cia which show only a single avi- cularium have an internal avicularium (plac- ed in the cavity of the zoteciumi; this avi- cularium is attached just inside the small area beside the external avicularium. X 40. The same species. The proximal end of a zocEcium with a single external avicularium. The ends of two interior robust spinous processes arc seen in the pro.ximal portion of the frontal area. X 75. The proximal half of a zoa;cium from the basal surface after the removal of the latter. An internal avicularium. four spin- ous processes and the horizontal part of the distal wall with its pore-chamber are seen. X 75.
The proximal half of another zoa'cium trea- ted in the same way. The mandible of the avicularium has been removed. X 75.
Fig 7 f. .Some zooecia of the same species from the basal surface. The internal spinous pro- ce.s.ses, the pore-chamber of the distal wall and the heart-shaped rosettc-plale arc seen. X 40.
— 7 g. Some zoa-cia of the .same species, lateral
view. The bent distal wall, the internal avicularium (a. v.) and a robust forked i)ro- cess are visible. X 55.
— 7 b. Some marginal zoa-cia of the same species,
lateral view. Two radical libres are seen to originate from their chambers &e. X 40.
— 7 i. An external avicularium of the same spe-
cies. X 55.
— 7 j. An internal avicularium of the same spe-
cies, lateral view. X 75.
— 7 k. The same avicularium without mandible,
from the frontal surface. X 75.
— 8a. Menipea ligulata Mac dill.. X 40.
— 8 b. The same species from the basal surface.
The pore-chamber and the rosette-plate of the distal wall are seen. X 40.
— 8 c. Some zooecia of the same species, lateral
view. The distal wall with its pore-cham- ber is seen and the peculiar internal pro- cesses, which are j)ointed in the zoa'cium with ooecium and furnished with an ex- panded, dentated terminal part in the others. X 40.
— 8 (I. A distal wall of the same snecics with a
heart-shaped rosette-plate and two pore- chambers. X 200.
— 8 e. Some of the internal processes, more highly
magnified. X 75.
— 9 a. Canda araehnoides (I.amx.). The oa'cia are
inclosed in avieularia. X 40.
— 10 a Hoplitella armata (Busk). X 2."?.
— 101). The same species, from the basal surface.
The proximal part of the zoa'cia is fur- nished with two long lateral expansions, but only with a single one in the mar- ginal zocecia. X 23.
— 10 c. The distal wall of the same species, fi'om
the proximal end. On each side is seen the transverse section of an expansion. The occlu.sor muscles of the operculum are al.so seen. X 55.
— 10 d. A longitudinal section through a zocecium
of the same s])ecies. The bent distal wall (d. w.) and one of the expansions are seen. X 40.
— 10 e. .\ longitudinal section through a marginal
zo(eciu])i of the same species. The internal aspect of the avicularium a. v.) and the strong marginal thickening, which sur- rounds the ro.sctte-i)lates, are seen. X 40.
(j-. UJ'. /,c/uri.\-<'/t , /Jfi/o i {jff .
/7//
miJ^
m
w
^i^
7i
I.Mrrli/K-fi rrij.s/<(//,,iK (.'rru/ ir .\lrii i(/fl//iii.i /////a VYio,,,/! ^ ./J/cti . /lii.siil ll'i/i, 7'/n.iii/l ', . .\ f,/i crMiwil is Mar („N S..yr/-,ir,<,r)'t/rrilri .■,rri/ii<( I'fir/ //irt GCii/ji/rd /:7/i.sii /■'Inn . 7 F/,l/>i'// 1 lUI ro/>nr<l/,i //i,ir/,s ,S' F/.i/j / njii /,i/<i Mii< O'l//
.9. f'rrrlr/'l i/rrlf/l/lol t/rx /.illilJ /O //o/l/l/r//tl llirilii/tl Hll.s/c
Plate III.
24
370
Plate III.
Fig. 1 a. A composite colony of Kugiila caliculala n. sp. X A.
— lb. The same species witli oii-cia. X 40.
— 1 c. Zooecia of the same species with oiecia,
from the basal surface. X 40.
— Id. An incipient colony of the same species.
X 23.
— 1 e. Another incipient colony of the same spe-
cies. X '2'.i.
— If. An incipient colony from the basal surface.
X 23.
— 1 t;. An old zod'cium and the adjacent internode
of the stem, seen half from the ))asal sur- face. The calcitied lateral border, \yhich is a continuation of the distal wall, is seen. Between the zocecium and the internode an internode of a new stem is beginning. X 40.
— 1 h. The proximal end of a young colony. X 40.
— 1 i. .A part of a young colony, on which an
internode of a new stem begins between the pro.vimal zocecium and the adjacent internode. X 40.
— 1 j. A part of a young eolon>' from the basal
surface. X 40.
— Ik. Two stem-internodes. X 40.
— 11. The adjacent ends of two internodes of the
stem. On the lower the distal wall and one of the lateral thickenings are seen, on the upper the two lateral thickenings annularly connected in the pro.ximal end of the inter- node. X 100.
— 1 ni. Two adjacent internodes of the stem, be-
tween which a new one is beginning. The lateral thickenings and the parietal mu.scles. X 100.
— In. The distal end of a new-formed internode
of the stem (in an inyerted position) with parietal muscles. X 100.
— 1 o. A new-formed stem-internode beginning be-
tween two older ones. X 40. — 1 p. An ayicularium of the same species. X 100.
— 2(
— 2(
- 2g
— 2h.
Fig. 1 q, A transyerse section through a steni-inter- node to show the two lateral thickenings. X 100.
— 2 a. Riigiila caraibica n sp. X 1.
— 2 b. The same species. A part of a branch, from
the frontal surface. An ayicularium is .seen. X 40.
The same species. Ooecia. X 40. Id. The same species, from the basal surface.
Distal walls and oiecia are seen. X 40. e. A young colony of the same species. X 17. f A somewhat older colony with a single long stem-internode. X 17.
.\ stem-internode of the same species. At the ujjper end the original place of one of the fan-shaped branches is seen. X 17. Another internode of the stem of the same species. X 17.
The distal end of a stem-internode. more highly magnified. The internal supporting ribs of the distal wall are seen and the rosette-plates of the fan-shaped lateral branch. X 40.
The distal end of a stem-internode in an- other position. The hent distal wall with its rosette-plates and supporting-ribs is seen. X 40.
A transverse section tliiough a stem-inter- node. The two lateral thickenings are seen. X 5.'-.. 2 1. The distal wall of an internode of the stem, yiewed from above. X 7.'j.
2 m. .A longitudinal section through the upper- most end of a stem-internode. The distal wall with its rosette-plates and one of the lateral thickenings are seen. X 7.).
2n. Another longitudinal section through the upi)ermost end of a stem-internode. The distal wall's supporting-ribs are seen and the distal wall of the lateral branch. X 75.
3 a. Two stem-internodes of Bugiila glabra (Hincks). X 40.
- •'2.i-
— 2 k.
Ci'. f/./i' /.coiiisfii . /t'/i/o '. tia .
f'l m.
/ /'irrjii/ri r S/iryiriri<i I //f/i/tloiii //>/•/■ 2 /liiff. ^X/irf/J > ti//ii/>irti . f/ .\yi
Plate IV.
24*
372
Plate IV.
i-'if!. 1 ;i. Dinwrphozoon iiohilc (Hincks). The four lowermost zcHucia have low cup-shaped oaH'ia. X 23.
— 1 b. Zod'cia of the same species, lateral view.
As the lateral walls in the ligure are not split, only rosette-plates are seen. X 23.
— 1 e. A transverse section tliroUf,'li a colony show-
ing its two layers with e.\trcmcly dllTcrent forms of zoiecia. In two zoieeia the vertical part of the distal wall is seen with a multi- porous ro.selteplate. Three small vaulted rosette-plates are seen between the two layers. X 40.
— Id. The basal surface of some calcilied zocecia
after the removal of the membranous zoce- cia. The rosette-plate of the lateral wall is seen and on one of the zocjecia two uni- porous rosette-plates. X 40.
— 1 c. The distal end of an avicularium of the
same species. X 75.
— If. Zocecia of the Alcyonidium-layer of the same
species. X 23.
— 2 a — 2 e. A series of developmental stages of the
ooecium of Dendroheaniu Murrdiiana i.Iohnst.); endo- the endood-cium: ecto- the ectooce- cium. The first four figures show the ascend- ing part of the distal wall, the two lateral halves of which meet at an angle. The first three also show that the spines arise as folds in the lateral margins of the zooecium. X 40.
— 3 a. Bicellaria ciliata iL.). The uppermost zooe-
cium shows a rudiment of an ocecium, and the lowermost the mark left by a detached OfEcium (ov.). Proximally to this the forked distal wall is seen. X 40.
— 4a— e. A zonccium with ooecium of C.oriiiicopina
infunclihulala Busk) in three different posi- tions. The distal wall is .seen in 4 b and 4 c. X 23.
— 4d. A sagittal section through the saine o(Ecium-
bearing zocrcium; it shows that the ooecium is surrounded by a kenozo(ecium. X 23.
— 5 a. Two zo<ccia of Cornncojiina grandis 'Busk),
showing a finely dcntated cry|)tocyst. X 40.
l'"ig. 5 b. The same zonecia, from the basal siii-facc. X 40.
— 5 c. A zooecium of the same s])ecies with a large
avicularium. X 40.
— 5d. The frontal surface of the avicularium. X 40.
— 5 e. The avicularian mandible. X 55.
— 6 a. Hiaritopora raJicifera Hincksi. X 23.
— 6 b. The same sjjccics, from the basal surface.
X 23.
— 6 c. An avicularian mandible of the same species.
X 55.
— 7 a. Didymia simplex. Busk. The central zo(e-
cium with an oa'ciura enclosed by a keno- zo(Ccium. X 40.
— 7 b. A zofEcium of the same species with o<i'-
cium, from the frontal surface. X 40.
— 7 c. A zod'cium of the same species with o(i'-
eium, from the basal surface. The arched distal wall is seen between the zocveium and the kenozo(Ecium. X 40.
— 7 d. A sagittal section through a zooecium of the
same species with oircium. X 40.
— 8 a. Dimelopia corniita Busk. X 40.
— 8 b. A zo(Ccium of the same species with ooe-
cium, from the basal surface. The pore- chambers and the oval uncalcified part of the ectooa-cium are seen. X 40.
— 8 c. A zoa'cium of the same species from the
basal surface. The pore-chambers and their rosette-jjlatcs are seen. X 55.
— 8 d. The distal wall of the .same species, viewed
from above. X 55.
— 8 e. A sagittal section through an oa-cium of
the same species. The outermost line seen at a part of the basal surface of the figure ought not to have been seen outside the cctoocecium as it gives the incorrect idea that a covering membrane is found here. X 75.
— 9 a. Brettia simplex (Mac Gilliv.). A zoiecium
from the frontal surface. X 40.
— 9 b. A zooecium of the same species, lateral view.
X 40.
// /' /, cl'nisrN /j/[f/o : o n .
pi.n^.
/. /irruiiii /i/iAitix //r,i>/.x ^.Muf/ti//i A/itrrriijiina Jii/uisf .1. liirfZ/firiii ii/ia/a /. '/ /I'lr/// iri/iiiiih/,ii/<i/ii /.'iis/.
"i. /Iirr// yiriiir/is A'tis/r (i /irtirlitl r<u/iii/'orn //iiirAs 7//ir/i/tiiiri si iiifi/fj- ftii.tA .
il'./Ji//if/i///rti rorriii/it 6'iisA- .\//>fi/rs/o/ii(f xiriifi/rj' A/iir O'i//
Plate V.
374
Plate V.
Fig. 1 a. Biigula dentata (Lanix.), from the basal sur- face. The di.stal wall is furnished with two very long desceiiding lateral parts X 40.
— 1 b. Zod'cia of the same species, lateral view.
One of the distal wall's lateral parts with its rosette-plates (d. w.) is seen. X 40.
— 2 a. Butitila dissimilis (Busk). X 23.
— 2 b. The same species, from the basal surface.
The strongly angularly bent distal wall is seen. X 17.
— 2c. A zod'cium of the same species with oce-
cium, lateral view. X 23.
— 2d. I'he distal wall of the same species, viewed
friini above. X 40.
— 3 a. Stef/anoiiorella neozelanica i Busk\ X 23.
— 3 b. The same species, lateral view. Two distal
walls are seen (proximally to the first and third rosette-))late); in a line with the se- cond and the fourth rosette-plate the polyp- ide tube and an opesiular outgrowth are visible. X 23.
— 3 c. Four opercula of the same species. X 40.
— 3d. Transverse section through four zotrcia of
the same species. In two of these the dis- tal wall with two multiporous rosette-plates are .seen and in the two others a trans- verse .section of the polypide tube and of the long canal which meets its frontal wall. X 23.
Fig
4 a. 4 b.
4 c.
5 a. .5 b.
,5 0.
6 a. 6 b.
6 c.
7 a. 7 b. 7e.
7d.
Steganoporclhi neozelanica Busk), var. mag- nifica. X 23.
.The same form, from the basal surface. The polypide tube and the lines in which the two opercular outgrowths meet the basal surface are seen. X 17
The same form, lateral view. The same parts as in Fig. 3 b are seen. X 23. Steganoporella maijnilabris (Buskl X 23. The same species, from the basal sur- face. Two rosette-i)lates and a correspond- ing opening are seen. X 17. The same species, lateral view. X 23. Steganoporella Biiski Harmer. X 23. The same species, lateral view. The crypto- cyst joins the basal wall. X 23. A distal wall of the same species. The lines in which the cryptocyst meets the distal wall are seen.
Steganoporella lateralis (Mac Gilliv.) X 23. The same species. X 23. A zorccium of the same species with cover- ing membrane and operculum. X 23. The same species, from the basal surface. In the two distal zo<rcia the basal wall of the polypide tube is formed by the basal wall of the zooecium. X 23.
%
(/' . 1/ /t'./.r/i/ fi.v/'f/ , /I'rijo :oii
Sh
Wih.^^^
VI ^r^
:i,>
/'/,/'
JC'
v"l
,/,r
1
O '1
COy
\%A
W^
m^-'
W>^'
m <'
w
W^ S-!
/ //„y„/,, <l,',>l.,h, Uu„..-. 2 H,.,j. ,/,...„>,,/,.■.■ Bus/.- .lSh;,a„of,orr//„„<'o;rl,nn,;i liusk 't.Shf,.,,,. n-o;,llnni^<i ',„„■ ,„„<,„,/■„<, li„s/c^ i.Sh:,,u, „„.,/,„/.,6r,-s- Ji„.:/.-. fi Shyur n„.,lu /f,n„,rr 7 Sle,/an . l„/.;;.t,. .\t,rr f,',// .
L
7
Plate VL
;J76
Plate VI.
Fig. 1 a.
— 2 a.
— 2 b.
— 3 a.
— 3 b.
— 3 c
— 3d.
— 5 b.
— 6 a.
— 6h
— 6 i
Crnleroporn falcala n. ,sp. X 23. Sipl}nnoi>orella noilosii llincks. X 40. The same speeics from the basal surface. X 40.
Siphonopnrclla delicalissima (Busk). The covei'iiij; nuinbrane is removed. X 40. A zod'chim of the same species, more highly magnified. X ".">.
A ziKvcium of the same species. As a great pari of the frmilal cryptocyst has been re- moved, the proxinially directed ])art of the polyjiide tube can be seen. X 75. The same species from the basal surface. Tile polypidc lul)e is visible. Labioponi creniilata n. sp. X 23. Thalamoporellii iirdntilala. var. stapifcra n. X 40.
A gonozod'cium of the .same s])ecies, the oiccium of wliich has been removed. X 40. Spicula of the .same form. X 200. Two zooccia of the same form, seen from the basal surface. A <listal wall of the same form. Thalamoporella Hozieri (Aud.), var labiata n. X 55.
The same form, from the basal surface. X 40. A zoceeiuni of the same species, from that lateral surface which is nearest to the deep- est opesiular outgrowth. X 40. A zocecium of the -same species, from the other lateral surface. X 40. The distal end of a young zocecium of the same form. The lip is not developed. X 55. The distal end of an older zocecium with a fully developed lip. X 55. The distal end of an older zocecium with operculum. X 55.
The operculum of the same form. X 100. A distal wall of the same form, which is exceptionally furnished with two multi- porous rosette-plates. X 40.
Fig 6 j. A distal wall of the same form with a single multiporous rosette-plate. X 40.
— 6 k. Spicula of the same form. X 200.
— 7 a. ThitUimoporcUa lioticha (Ortm.). X 23.
— 7 b. The distal end of a zocecium of the same
species. X 40.
— 7 c. Spicula of the same species. X 200.
— 7 d. A series of zocecia of the same species with
o(ecia, lateral view. X 23.
— 7 e. A Scries of zocecia of the same species with
(xecia, fnun the frontal surface. X 23.
— 7 f. A gouozoa-cium of the same species, with
developing ocrcium. X 40.
— 7 g. A schematic longitudinal section through
the distal end of a gonozo<ecium with ote- cium of the same species.
— 7 h. .-Vn (xeciuni of the same species; as its frontal
half is cut away, the operculum of the gono- zod'cium can be seen. I.owcrniost the pro- truding od'cial ojierculum. X 40.
— 7 i. The same species from the basal surface
The descending cryptocyst divides the zo<e- cium into a smaller distal chamber and a larger proximal. The basal wall shows in every zocecium a uniporous losette-plate or a corresponding opening. X 23.
— 7 j. A zoiecium of the same species, from one
of the lateral surfaces. X 23.
— 7 k. A zocecium of the same species, from the
other lateral surface. X 23.
— 7 I. An avicularium of the same species- X 40.
— 7 m. A distal wall of the .same species. X 40.
— 7 n. A gonozo<Ecial operculum connected with
the appertaining (xecial operculum. X 40.
— 7 o. The same two opercula in another position.
X 40.
— 7 p. The distal end of a zocecium of the same
species after the removal of the basal sur- face. The independent basal wall of the polypide tube is seen. X 40.
(i M /f /.efHnsffi /J/i/(f
f/o ifjf/
Plate VI a.
378
Plate VI a.
Fig. 1 a. Tluiltimoporella graiuilala n. sp. X 40.
— 1 b. The s;iiiu- species, from the basal surface.
X 23.
— 1 e A gmio/.iKL'eiuiii nf the same species with a
ileveliipiiiH ooccium. The gonozoCEcial oper- culum is seen. X 40.
— Id. An avicularian nianiliblc of the same spc-
X :>:>)
— 1 f. Spicula of the same species. X 200.
— 2 a. Th(iltimoi>ortlla iininiiliita, var. tiihifeni n.
Within the aperture both of the zocecia anil of the avicularia, the remarkable continua- tion of the polypide tube (t) with its frontal aperture can be seen meetinj; the distal wall. X 40.
— 2 b. The same form from the basal surface. The
continuation of the polypide tube (,t , which sends a lateral branch to a rosette-plate in two of the zooccia, is visible inside. This continuation has a peculiar trapeziform shape in the (<onozo<i'cium. X 23.
— 2 c. A zocfcium of the same form, lateral view.
It is seen, that the continuation of the poly- pide tube meets the basal jnirt of the distal wall. X 40
— 2d. Two gonozocrcia of the same form with
ooceia. X 40.
Fig. 2 e. Spicula of the same form. X 200.
— 3 a. TlmUimojmrdla novae hollandiav (Hasw.).
X 40.
— 3 b. The same species with a somewhat smaller
avicularium. X 40,
— 3 c. Two avicularian mandibles of the sajne spe-
cies. X 40.
— 3 d. The same species, from the basal surface.
X 23.
— 3 e. Another colony of the same species, from
the ba.snl surface. X 23. - 3 f . ,Si)icula of the same species. X 200.
— 4 a. Tlmlamoi>orclht Jervoisi (Hincks). X 40.
— 4 b. The same species from the basal surface.
X 23.
— 4 c. Operculum of the same species. X 40.
— 4d. Spicula of the same species. X 200.
— .'i a. Thalamoporella mamillaris (Lamx.l. X 40.
— .">b, Five opesiuUe of different zon?cia, to show
the variation in shape of the opesiular out- growths and in the number and structure of the protecting spinous processes. X 75.
— .1 c. An avicularium of the same species. X 40. ,') d. An avicularian mandible of the same spe- cies. X 75.
— 5 e. Spicula of the same species. X 200.
0. . ////^ /.ff/f // .\f// /h'YOXO^ty.
PlWrt
/. Tkalririto/torf//rt r/rtiiiti/tt fa /t.wt. -. '/7t ft/am. yrtiftiiiftht . uar- /uii/tr/i . .'S- T/utiafft . nooae fto//aiiefiaf //nsrv i 7'/in/nm ■/rrvoixii //inr^s -J. T/inJM»L rnami/JtirU /.orn-r.
Plate VI b.
380
Plate VI b.
Vifi. 1 a. ThalanioporeUd liozieri (Xud.^, vav. proininens n An irrc'milarly jointed colony. X 12. The same form. X 40.
Zoa-cia and an avicularium of the same form, lateral view. X 40. An operculum of the .same form. X 75. The .same form from tlie basal surface. X 40. Spieula of the same form. X 200. Thalanioporellii liozieri iAud\ var. cali- fornica n. X 40.
Ofccia of the same form, of which tlie dis- tal only appears as a rudiment. The distal gonozotrcium is furnished with an oper- culum. X 40.
Chitinous thickenings on the gonozooecial operculum. X 100.
The same form from the basal surface. X 40. — 3 a. Thalamoporella liozieri lAud.), var. sparsi- piinctala n. X 40.
1 1). 1 c.
Id. 1 '
1 f. 2:
2 b.
2e.
2d.
1-ig 3
— 4
— 5
— 5
— 5
1). The .same form from the basal .surface.
X 40. a. ThalamoporcUn lioticha (Ortm i. A row of
zoiveia, from the ba.sal surface. X 2;{.
a. Thalaiiii>i>i>rclla I'.rixmsii n sp. X 17.
b. Opereuluni of the same species. X 40.
c. The same species from the basal surface.
X 17.
d. An avicularian mandible of the same spe- cies. X 40.
e. Spieula of the same species. X 200.
a. Thalamoi>orclla falcifera (Hiuck.s). X 40.
b. The same species from the basal surface. X 40.
c. An avicularian chamber of the .same spe- cies. X 55.
d. An avicularian niaudible of the same spe- cies. X 75.
c. Spieula of the same species. X 200.
M.n h
if/r .s/i<tf\\rftnnr//f/fi. ^ Tfifilarn S/n///ii //rnrAs rrrr, .7 77t rf f ft m . e .»yt ri ti .vet n.x/i. (i 77tf//rt/fi . /fi/rirera 77/nrA:v.
Plate VI c.
382
Plate VI c.
Kig. 1 a. Thalamoporellu Harmeri n. sp. X 2;!.
— 1 b The same si)ccies witli aviciilarium. X 40.
— 1 e. Tlic distal end of a zooccium of the same
species. X 55.
— 1 (1. An operculum of the same species. X 100.
— 1 e. The same species. .A gonozoircium with a
devclopinn ooecium. The gonozorecial oper- culum is seen. X 40.
— If. Zoa'cia of the same species, from the basal
surface. X 40.
— 1 g. Zooecia from another part of the same colony,
from the basal surface. X 40.
— 1 h. Spicula of the same species. X 290.
— 2 a. Aspidostoiua giganteuni (15iisU\ Two ooeeia
are seen. X 23.
— 2 b. A longitudinal section through two zooecia
of the same species. X 23.
— 2 c. A transver.se section through two zoiccia of
the same species. Uppermost a distal wall is seen and to the left of this the arched distal end of the zoircium. Further down an intersected polypide tube is seen and on eacli side of tliis a recess whicli extends to the basal wall. X 23.
— 2 d. A transverse section through a zoa'cium of
the same species. The median projection of
seen beneath tlie polypide
the zooecium tube. X 23.
Fig. 3 a. Aspidostoma ''!'< Aef/on (d'Orb.). The two projections at the ])roximal part of the oce- cium are united so as to form an arch- shaped belt which covers the aperture of the gonozo(Eciuni. To the left a gonozo(eciuni is seen, im which this belt is broken. X 40.
— 4 a. Asi)iilostonia (?) Antiopa (d'Orb.). The two
])rojections at the proximal j)arl of the 0(eeium have not united. X 40.
— 5 a. Aspidostoma l? Atahiniha id'Orb.^ with ooe-
eia. X 4(1.
— 5b. The same species withovit oiecia. X 40.
— 6 a. Aetea dilaiatti Husk. The incrusting portion
of four zoircia. The opening near the distal wall is from the broken perpendicular part of the zooecium. X 40.
— 6 b. A distal wall with rosette-plates. X 200.
— 6 e. A part of the surface of the perpendicular
part of a zotecium on the border of the dilated distal end. The dark lines and spots are uncalcitied areas. Immers.
— 6(1. A part of the surface of the incrusting part
of a zooecium. Immers.
6'. \J /I'/.roi/isrn , Briyo : on
/'/ IV,
1
r^'-'(4\
A/
//j
I 'r/iii//iriitifii>ri'//ii llrirriirfi rt.sp.. 2./l.-ifi.Ldos/orrui gi'aanicutn A'i/aA-. .3. A.i/ii<l."".lft/uri </'Oi/t. 'i .ls/ii<l' ".tidm/Ki </ Ort,
5. A.ipirl'"Ala/ari/Aa, d'Orh. fi.Aelea. dUtUala. JJusk .
Plate VII.
384
Plate VII.
rig.
Id. •2 a
2 b.
1 a. Macropora centralis Mac Gilliv. X 23. 1 b. Tbe apeiture of a special form of /.occcium (avicuiariiiin '? of the same .species. X 4(1.
1 c. Au operculum with its surrouiuliiit;s of the
same species. X 40.
\ pore-chamber of tlie same species. X 40. Miiiihranicellnrid diibki lUusk), with cxecia. the clongatcil he.vafjoiial zocrcia are partly visible throuj^li tlie frontal surface, wliich is divided into hexagonal, rliombic areas. X 17.
The same species from the basal aspect after removal of the basal surface. The cavity of the eloufjated zoa'cia is visible and the hexagonal, rhombic areas of the frontal surface are seen at the same time. On the distal portion of each zoa-cium an oceciuni (,0V.) with its oblique, basal surface is seen. X 17.
2 c. Zooecia of the same species with o<rcia. The
covering membrane is removed. X 17. 2 d Hosctte-plates of the same sjjecies. X 7.').
2 e. Zod'cia of the .same species. The separating
walls of the elongated zo(Ccia arc visible through the frontal surface, divided into broad areas. X 17.
3 a. Alysidium parasiticum Bunk. A gonozocecium
with a double-valved oa'cium is seen on the lowermost zocrcium. X 40. 3b. A zocccium of the same species. X 75.
A zotccium of the same species from the basal surface. The bent distal wall is seen. X 75.
A longitudinal .section through a zooecium of the same species. X 75. A gonozocecium of the same species from the frontal oceciabcaring surface, after the removal of the oa-cium. The two elongated openings are seen, through which the nn;- cial valves have been in communication with the pore-chambers of the gonozodcium. X 75. A transverse section through the distal end of a zod'cium. A row of uniporous rosette- plates is (very indistinclj' seen. X 75. The end of a branch of the same species with a cylindrical internode. X 40.
— 3c
— 3d.
— 3e.
3 f.
3g.
Fig. 3h. A gonozocecium with the o(Ccial valves open. X 55.
— 3 i. An oo-'cial \al\c tVoni the internal surface.
X 55.
— 3 j. A gonozocecium with ocecium, seen from the
basal edge. X 40.
— 3 k. A gonozocecium with developing ocucial
valves, lateral view. A lateral pore-clianiber and a part of the basal one are seen. X 75.
— 3 1. The same gonozocecium, from the basal
edge. X 75.
— 3 m. The stem of the gonozocecium. The distal
wall (,cl. w.j and a uniporous rosette-plate are seen. X 75.
— 3n. The stem of the gonozocecium, lateral view.
Opposite the pro.ximal part of the oval de- pression the oblique distal wall is seen. X 75.
— 3 o. An oblique section through the middle part
of the stalU-like kenozocccium, seen from the basal surface. The three rosette-plates of the distal wall are seen. X 75.
— 4 a. A longitudinal section through Celliilariii
oustralis Hincks. Above the majority of the zocccial chambers an ooecium (ov.) is seen. X 23.
— 4b. A transverse section thiough a portion of
the same species. The ocecial cavity (ov.) and the arched rosette-plates of the lateral walls are seen. X 40
— 4 c. A transverse section through a portion of
the same species. The ocEcial cavity (ov.) and the rosette-plates of the distal wall are seen. X 40.
— 4d. A portion of a longitudinal section of the
same species, more highly magnilied. A zocecium with two rosette-plates and an ocecium (ov.) are seen. X 40.
— 4 c. A longitudinal section through the proximal
part of an internode of the same species.
— 4 f A longitudinal section through an internode
of the same species, showing developing oircia (ov.). X 23.
— 5 a. A row of zocecia of Celliilariu /istiilosa (?)
(L.) with ooecial fissures. X 40.
a.A/ /f /,rr/i/isr/i /i'ri/ozruc
/'/ 17/ .
/ .l/,.,„f,or<i r<;i/r,i/,.i':''Mij,- fnl/. 1'. J/cin/irruiuel/firta t/u/iiti Busk. -3. Ali^i-i</iiir/i /in/ftsi/icurn j7us/c.
i. CeUaria ait.?frn/is Hi/icA\s Of/ /is/iilosa '■" /.
Plate VIII.
25
386
Plate VIII.
Fig. 1 a. Cellularia rigida, Mac Gilliv. 'I'hc tlirce zouecia with oiccia. X 40.
1 b. A longitudinal section through two zorecia
with oa'cia (ov\ At the centre of the broad di.stal part of each zooccium the narrow proximal part of a neighbouring zoa-cium is visible. X 40.
— 1 c. A longitudinal section through a part of an
intcrnode, wliich shows developing ocecia (ov). X 40.
— Id. The same species. A section parallel with
the frontal surface to show the elongated, narrow shape of the zofccia. X 40.
— 2 a. Cellularia allanlica Husk). Four od'cial aper-
tures arc seen. X 17.
— 2 b. A longitudinal section through a colony of
the same species. Developing ooecia are seen. X 17.
— 2 c. The same species, from the basal aspect
after the removal of the basal surface. The cavities of the zoiecia and the occcia arc vi- sible, and here and there external ridges which divide the frontal surface into areas. X 17.
— 3 a. Micropora Nonitaiii n. sp. witli calcified
opercula. X 40.
— 3 b. A longitudinal section through a zon?cium
of tlie same s))ecies with oa-cium. X 40.
— 4 a. A longitudinal section through a zoctcium
of Micropora /lerforata (Mac Gilliv.), with onccium. X 40.
— 5 a. Foraniinella lepida (Hincks). A rudiment of
an on?cium is seen uppermost. X 40.
— 6 a. A colony of Chliilonia Cortlieri Aud. X 12.
— 6 b. A colony of the same species with the bran-
ches in one plane. X 12.
— 6 c. An intcrnode (kenozoa'cium) of a main-
branch with a zod'cium rising from it. The segments indicated by «, /?, >' and d corre- sjjond with similar segments in the inter- nodes of the trunk and the main-branches. X 55.
— fid. A zoncciura, lateral view. The concavity of
the frontal surface is seen greatly thickened in its distal half; in the distal part of this concavity a smaller one is .seen, correspond- ing with the small distal pore in fig. 6 f . Farther backwards is a connection between the frontal concavity and the cavity of the zooccium corresponding to the second pore in fig. 6 f. d. w. — the distal wall. X 55.
Fig. 6 e. Separating wall with rosette-plate in the stolonate net-work. X 200.
— (i f. A zoa-cium, from the frontal surface. X 55. — - 6 g. Two internodes (kenozoa'cia) of a main-branch
with some of the adjacent zooccia. X 75.
— (1 h. The forked distal intcrnode of the stem. X 75.
— () i. A |)ortion of tlie stolonate network with the
proximal part of a stem. X 75.
— ''>,i-ni. Cylindrical internodes being transformed
into zo(ccia bj' the development of a cup-shaped expansion (the zoiccinm in an embryo state) from the proximal part of the intcrnode. X 55.
— 6 n-q. Cylindrical internodes which apparently
are changing into zo(Pcia by a gradual swell- ing of the intcrnode. X 55.
— 6 r. A cylindrical intcrnode with its cup-shaped
proximal expansion, from the frontal aspect. X 55.
— 6 s. A transverse section through a zocccium.
Tlie thick frontal wall, the small concavity (corresponding with the distal jiorc in lig. 6 f.) and the ro.selte-pIate of the distal wall arc seen. X 55.
— G t. An intcrnode of the stem, lateral view. Hc-
tween /J and y a distal wall with a unipo- rous rosette-plate is seen. The funnel-shaped concavity is in communication through a pore with the interior of the zocecium. X 75.
— (in. An intcrnode of the stem, from the frontal
surface. The oval funnel-shaped concavity with its pore is .seen. X 74.
— (i v. A quite young intcrnode of the stem, the
walls of which are still very thin. On ac- count of this the extent of the distal wall (d. w.) is considerable, and the funnel-shaped concavity is not yet developed. In its place is found an oval opening. X 71).
— 6 X. A young intcrnode of the stem, from the
basal aspect. The uniporous rosette-plate is seen as also the oval opening. X 75.
— lly. A forked cylindrical intcrnode connected
with two single ones. Between /i and y the distal wall is seen with a uniporous rosette- plate. X 100.
— 7 a. A longitudinal .section through Foiwolnria
rlliplica Busk. An avicularian chamber and an otccium are seen. X 23.
— 7 I). An articulated operculum of the same spe-
cies. X 40.
(i.U /t./.iDi ri St/I , /if//o :ofi .
PI V III
/. f'rl/firi(/ //ryii/fl ,llnr /','/// y <",//. ti//t/////rr/ A'u.v/,: .'/. .If/mj/to/'ft corlctrer/ /-.'.sf/rr 0 .Ifirr /if/'/'oia/tl .IJrlr fi'i// ,'j. J//,/- ////,, /fl //i/u/,.\- 0 ('/i/lr/orlltl Cn/f/icri .1////. 7 /'oiii'ti/iiiKl r//iyi/ir,l A'l/s/,-
/irtnt*ti bu .
r'C^rii^., l,-/A.
Plate IX.
25*
388
Plate IX.
Fig. 1 a. Electro {Ilcleroofciiim) nmiileclens llincks. with ocrcium. The small denticles are not only seen at the margin of the membranous area, but arc also visible through the ealei- licd wall of the frontal surface. X 55.
— lb. The frontal wall of the same species, from
the internal surface. X 75.
— 1 c. A variety of the same species. The lower-
most zocvcium has been regenerated. X T.'i.
— 2 a. Electni zoslrricold (Nordm.). The uppermost
zooccium with odciuni. X 40.
— '2 b. Two zoiecia of the same species. The up-
per with ocecium. X 55.
— 3 a. Calhiporn Dnmcrili (Aud.) Two developing
occcia in difl'erent developmental stages. X 55.
— 4 a. Callopora attrila (Hincks). Uppermost a
developing oiecium is seen, lowermost an oci-cium in which the proximal part of the ectooucium is not lakified. X 40.
— 5 a-h. DilTcrcnt developmental stages of the
ooecium and the covering avicularium of TegclUi iiriicnrnis (Fh-m.). endo — the endo- (xicium, ecto — the ectootecium. In fig. 5 d the uniporous rosette-plates, destined to connect the avicularium with the zoa'cium, arc seen distally to the oiccium. In fig. 5 e the first sign of the avicularium is seen as a transverse ridge pro.vimally to the mem- branous frontal area. In 5f — 5h the avicu- larium. X 40.
— 6 a-c. DilTcrcnt developmental stages of the
Ott'cium and the covering avicularium in Tegella SophUic [Uu&k). In Ob which is younger than 0 a) distally to the developing orccium arc seen two oval incisions which in fig. () a have closed themselves. It is the beginning of the two rosette- plates which should connect the avicularium with the zoa'cium. Kig. (i c corresponds in the degree of development of the avicularium with
fig. 5 f. The two rosettc-platcs are seen. X 40. Fig. 7 a. Klectra bicolor l^llincks). X 55.
7 b. The same species. Heproduction of a zoie- cium. X 75.
— 7 c. A transverse section through a colony. In
two of the zoctcia the distal wall with rosette-plates is seen, in two the immersed cryptocyst. X 75.
— 8 a. I'elalosiefiiis bicornis (Busk). X 55.
— 8 b. A zoa'cium of the same species, seen a
little more from the side X 55.
— 9 a. Memhranii>orcll<i disUins Mac Gilliv. X 55.
— 10 a. Two zo(ccia with oiccia of Cribrilinii annu-
/((/<( iFabr*. The oiccia are covered by keno- zorecia and on these some pore-chambers are seen. X 40.
— 10 b. A longitudinal section of the same species
through a zoacium with o<i'cium. X 55.
— 11 a-c. Three dilTerenl developmental stages ot
the oa'cium of Crihrilina punctata Gray. X 40.
— lid. An oiccium of the same species. The endo-
0(ccium is visible through the broken ectooa'cium. X 40.
— lie. The distal end of a zoacium of the same
species with occcium. from the basal sur- face. The porc-chambcrs of the zoa'cium and kenozoacium are seen. X 40.
— 11 f. rr/Vin/i/K/ /)(;/»■/(//((. I'ore-chambcrs are seen
on the three marginal zocccia. of which the central abnormal one has no aperture. X 55.
— 1 1 g. The same species, from the basal surface.
I'orechanibers (p. ch). X 40.
— 11 h. .Sagittal section through a zoojcium of the
same species with o<ccium. The oa'cium is enclosed in a kcnozotccium. X 55
— 12 a. I'licllina Cattijac (Husk), with oa-cia, from
the basal surface. Uoth the zoacia and the kcnozoa-cia enclosing the oa'cia are fur- nished with pore-chambers. X 40.
O.Jf. /^./.r/j///.vr// . /i'rj/o : or/
Pl/X.
/. /:/<•<•/ /•<{ (Ufi/Ucrivus //i/n/.s. ^. /'.'// Mfs/frtro/// Aoffh/i. 3. Afrfnhrttrnfioro Dii rrierilil j-iuff ^f Air r/t6r. fl unfa f/irtr/cx
.^. Jfrr/t/>f: tfffir/if/n's /•'/t'/n. fi.Aff/uhr: So/f/z/tw /^ush'. T-Aictfiht- fftroiof //i nrk^. S. Peialosft'tfu^'i hicoritis Hn.sM.
SJ.MfnihrtifUffi'rcf/t/ r/fs/ar/s Jfftrd'il/. HK ('fi/in/4ii<i mi/i u f<il<i Ffiiir: ff.C/thr fittficfd/ti (rrrn^ ■ Cri hn f/ff/Zf/f/r />f/s/,\
Plate X.
390
Plate X.
i-i«. 1
1 d
1 1
1 h
a. Kelepora lieiini<iiui King. i>ii Ihidrtiiilcs noirc- gicti. Tlu' colony, of wliicli the uppermosl part is removed, i.s attached l)y a hirge phite- like expansion, formed b_v kenoziKVoia, and the external snrface of the eolony is HUe- wisc formed by a kenozooeeial layer. X I'i.
b. The same species. ()(i-cia in different devel- opmental stages. X 40.
e. A developing colony of the .same species, consisting of one ancestrula, two fully devel- oped zocveia and two developing zoieeia. X 40.
A somewhat older colony of the same spe- cies, in which a root-e.xpansion of kenozote- cia is already formed. X 17.
f. A young colony of the same species, viewed from above. X 12.
g. A portion of a root-expansion from the colony in 1 d) more higlily enlarged. The distal walls furnished with a uniporous rosette-plate are seen between the youngest developing kenozooccia and the kenozoa'cia on the inner side. X 40. A portion of the same expansion. A finished kenozocrcium with avicularium is seen, and besides, four developing kenozoacia, which, like those shown in fig. 1 a, have had a membranous cover, which has disappeared after boiling in potash. X 40. Reicpont cellnlosa Smitt. The proximal |)art of an old colony cut acrcss transversally. The superficial kenozooeeial layer is seen. X 12.
The same piece as shown in fig. 2 a, but the transversally cut surface is seen. Tlic three groups (2, 4, 6) of small round apertures, almost in the centre of the section, are intersected zod'cial chambers, which on both sides are covered bv kenozocecia (see page 293). X 12.
I'-ig. 2
2 b
2d
— a a
3 b
4a
4b
4 c.
4d
A tiansverse scclicm thruugh a nnuii young- ger portion of the same colony. The zoivcia are also here on both sides covered by keno- zocecia. X 12.
A part of the transverse section in fig. 2 b, more highly magnified. The separating walls furnished with uniporous ro.sette-plates are seen betwen the kenozotecia placed above each other. X 40.
Another part of the same transverse section, in which the cavity of the kcnozooecia is much narrower. X 40.
Retcpora WallicliktiKi, Busk. Stalked oneeia. X 40.
A transverse section through a branch of the same. Three zoa?cia and two kcnozorrcia are cut through. X 40.
A transverse section through a branch of Rctepora tesselala Hincks. The small holes are transverse sections of kenozocecia. X 2.'i. A transverse section through a younger por- tion of a colony of the same species. A layer of zooecia and a layer of kenozocecia are seen; in .some of the former the unijjorous rosette-plate of the distal wall is seen. X 23. A transver.se section through a colony of the same species with two lavers of zocveia. X 23.
The same species. A portion of the keno- zocreial layer. X 17.
a. A transverse section through a colony of Releponi lata Hincks. The small holes are from kenozocecia. X 23.
b. The same species. The zoa-eial layei', fron) the basal surface, after detachment of the kenozocecial layer. — 23.
e. The same species. A part of a keiiozocveium with avicularia from which poreeanals issue to the surface. A covered avicularium is visible in the distal part. X o.'i.
(/.. l/./i'./.r/'///.vr//, ///■//(/ \Off
H.X
/. /fe/e^l {>/■// /Jr,//ilrr/irl A'l/iry :^ /f,/,yi i<//ll/o.y,/ .V/ili// .J A'r/,// It „ //tc/llM//a /^n.sA-
Plate XI.
392
Plate XI.
Fifj. 1 a. Sriilicella /ilnqinslDiua (Husk). The lateral chambers arc funiislied with their niembra- MDUs walls. X 23. 1 h. .\ hi-zou'cial internode of the same species, from the ba.sal surface. 15etween the two zoieeia uppermost the adzo<ecial supra- scapular chamber of the mothcr-zodcium and lowei-most its adzodcial pedal chamber. The scapular and the infra-scapular cham- bers are united or incompletely separated. X 40,
— 1 c. The zod'cium which arises from the mother-
zo(ecium of the bi-zoiccial internode, from the basal surface. The floor of the two supra-scapular chambers is seen uppermost, whilst the membranous cover is removed. The latter is seen in li^ 1 a. The two infra- scapulai' chambers are also shown. X 40. 1 d. .V part of the same zo(eeinm, from the sur- face furnished with the small avicularium. The infrascapular and the pedal chambers are seen. X 40.
— 1 h. A part of the same zoiecium, from the sur-
face furnished with the large avicularium. The infrascajjidar chamber (on the basal surface) is seen and also the pedal; to the lell of the tip of the avicularium the floor of the supra-seapular chamber. X 40.
— 1 e. The dau(;hler-zo(eeium of a bi-zocecial inter-
node, from the e.\ternal surface. Uppermost the unseparated distal chambers tlic scapu- lar and the infrascapular), and under them the pedal chamber of the dauf«htcr-zoiecium and the adzoiecial pedal chamber of the niotherzoiecium. (sec fig. 1 b.). X 40.
— 1 f. The mother-zo(ecinm of a bi-zo(vcial inter-
node. I'ppcrmost the two unseparated cham- bers and under these the pedal chamber. X 40.
— 1 g. The zoirciuni which arises from a daughter-
zoiecium, from the internal surface (i. c. opposite an avicularium) (see fig. 1 a.) Up- permost the distal unseparated chambers and below^ the pedal. X 40. The same zoiecium, fiom the other surface. The corresponding chambers are seen. X 40. A sagittal section through a zocecium of Siiiticrllii i>l(iijiosloni(i (Busk,!. The angularly bent distal wall d. w.) and the cryptocyst plate ic. pi.) are seen. X 40.
1 k. A gonozocecium of Cat. playioslonia. var. sclifera. X 2.3.
1 1. A gonozoeccium of the same form, lateral view. X 2.3.
1 m. .\ gonozocecium of the .same form, from the basal surface. X 23.
1 j. The separating wall between the covering kenozoa-eium and the small spinous ba.sal chamber. X 40.
— 1
— 1
1-ig. 1
— 2 b.
2d.
— 2 f
3 a.
— 3 b.
4 a.
4 b.
— ()
An old bi-zo<ecial interiu)de of Sriilirella plnrjioslonid, v. sclifera. The aperture is clos- ed by a calcified plate, and this is further connected with a cryptocvst which is placed inside the sternal area and may finally form a continuous cover inside the last. X 40 Another old bi-zo(ccial internode of the same form. X 40.
A zo(ecium of Sciilicclht Wilsoiii (Mac Gil- liv.l On each side of the sternal area a large infra-scapular chamber is seen. c. pi. crypto- cyst plate. X 40.
A zo<eciuni of the same species, lateral view. To the left the infrascapular chamber and to the right the supra-scapular and the pedal. X 55.
A zod'cium of the same s|)ecies, from the basal surface. The whole basal surface is occupied by the supra-scapular and the pedal chambers. X 55.
The proximal end of the sternal area of the same species. The bridge between the two central fenestra; is not yet completed and its end is uncalcificd. X 75. The same part of a third zo<ecium. I'lie bridge between the two fenestra- is for the most part uncalcificd. X 75. A zo(ecium of Scaticclla amphora (Busk), lateral view. To the left the infra scapular chamber, to the right the supra-scapular and the large pedal chamber. X 55. A zoiecium of the same species, from the basal surface. The supra-scapular aiid the pedal chambers are seen. X 55. A zo(eeium of the same species with a very large avicularium. To the left the supra- scapular and the Infrascapular chambers. X 55.
A zoiecium of Srtit. urniiln iMac (iilliv ). lateral view. The supra-scapular, the infia- scapnlar and the pedal clianibers arc seen. X 55.
.\ zixccium of the same species, from the basal surface. The same three chambers are seen. X 55.
A gonozo(rcium of .Sciil. maniarilacea (Busk). X 40.
The same gonozott-cium, lateral view. X 40. The same gonozo(rcium, from the basal sur- face. X 40.
A gonozocecium of Seal, ivnlrirosa (Busk). X 40.
The .same gonozoieeium, lateral view. X 40. A gouozoa-cium of Scut, maculata (Busk). X 23.
The same gonozoa'cium, lateral view. X 23. The sternal area of the gonozoivcium and the two spines, more highly magnified. The small cryptocyst plate is .seen. X 40.
('.. U.fiJ.ef///f.s-cf/ . Br/yo :/,
y/jy
' ('ii/fiiiri//ti /i/iifjioxforna Busk. 2. Cat. H'i/sorti Merc GM J Calarn./i/tora jSus/c i . Cal. arnala Mac O'i'/J . • > <'ir/ r/inrynrifarea Siisk (J f'a/.rnn/riri>.-!n /iti.si- 7. Cn/. /nnrii/tt/a /ius/c
Plate XII,
394
Plate XH.
FiR. 1 a.
— 1 1).
— 1 c
1 d.
1 f, 1 1 1
— Ih.
3 a.
3 b.
— 4b
— 4 c
Sternal area and aperture of Cnaliiilhi bcne- costatn n. sp. (On the plate designated as Cat. haslala). X 100.
Sternal area and aperture of anotlier zoa'cium of the same speiies. X 100. Sternal area and aperture of <'.osliceU<t ha- slala (Busk) (from Twofold Bav). The long fi'ontal sinus, wliitli is not seen in tiic two preceding figures, is licre distinctly visible. X 100.
A part of the sternal area of tlic same spe- cies, from the internal surface. Outermost the margin of the crvptocvst plate, further in the frontal sinus. X 100. ,A gono/.oocium of the same species, lateral view. X 40.
A gonozo(ecium of tlie same species, from tlie frontal surface. X 40. The distal end of another gonozooecium of the same species. X 55.
A gonozo(Ecium of Costicella soIiUa n. sj). (The figure does not give a good representa- tion of the structure of the sternal area). X 40.
A sagittal section through a gonozoiecium of the same species. The endozoiecial ofecium, formed from the distal wall and covered by a keno/.oiecium is seen. X 40. The distal end of a zoieeium of Scuticella sacciiUila (Busk) (wrongly indicated on the plate as C. saccala). X 100. A trizocvcial internodc with occcium of Cla- viporella (on the plate, Calpidium] geminata Wyv. Thorn. X 40.
A similar internodc, on which the frontal wall of the od'cium and of the covering kenozocEcium has been removed. The basal wall of the endozoiecial oa-cium is seen. X 40.
A sagittal section through the gonozo(ecium and the occcium of the same s])ecies. X 40. A small avicularium of the same species. X 00.
Claviporella (on the plate Cal]>i(iiiiin) imsilla Wils. Two zocecia, lateral view. In the proxi- mal part of each zooecium the extremely small pedal chamber. X 26. An internode of the same species with occ- cium. X 40.
The distal end of a zooecium of the same species, from the basal surface after the removal of the basal wall. The suture in which the two spines meet is not .seen in this figure, but on the uppermost zooecium in fig. 4 b. X 75.
Fig. 4d. The proximal end of a zorccium of flic same species. The rudimentary pedal chambers are seen. X 75.
— 4 e. The inner wall of the pedal chamber, form-
ing a uniporous rosette-plate. X 200.
— 4 f. The operculum of the same species. X 100.
— 4 g. The scapular and the infrascapular chambers
of the same species. X 200.
— 5a. An internode with o(ccium of I'lcrorclla (on
the plate (.alpicliiim) rarinala (Busk). Neither this nor the following figure give a satis- factory representation of tlie structure of the sternal area. X 40.
— 6 a. An internode with occcium of Plerocclla (on
the plate Calpidiutu alata (Wvv. Thorn.) X 40.
— 6 b. Sagittal section through the gonozoivciuin,
the oiecium and the covering kenozocecium of the same species. X 40.
— 7 a. A zod'cium of C.rihricella rufa (.Mac Gilliv.),
lateral view. The small supra-.scapular cham- ber, the greatly bent infra-scapular and the slightly bent pedal chamber arc seen. X 55. A zoieeium of the same sjiecies, from the basal surface. The supra-scapular and the infra-sca])ular chambers are seen and less distinctly the pedal. X 55. A gonozotecium of the same species. X 40. A gonozooecium of the .same species, lateral view. X 40.
7 e. A sagittal section through a gonozo(ccium of the same species. X 23.
7 f. A portion of the sternal area of the same species, from the internal surface. The crvptocvst plate is seen. X 100. A zoiccinm of Cribricella crihraria i Busk), lateral view. X 55.
A zocccium of the same species, from the basal surface. X 55.
A portion of the sternal area of the same species, from the internal surface. The crypto- cyst plate is seen. X 100. HincksielUi piilrhrlld Ma])les., with iKccium. X 40.
A longitudinal section through a lateral mar- gin of a zoircium of the same sjiecics. Up- permost the small supra-scapular chamber and lowermost the inner wall of the long scapular chamber, which is connected witli the zoieeium through two uni])orous rosette- plates. X 75.
9 c. A transverse section through a zooecium of the same species. The extremely thick walls, which separate the lateral chambers from the zoojcium, are seen. X 75.
b.
I c. 'd.
(/.. UJi' /.r/ft //sr/i //ffJO^ o
PL\'/7.
!^..
'ir
ill. \
',,1
'ih
V
"\
;• 0 ■ ^1
^f "^
S n
"^ ,^^
o O >
.u
y
^•".Xc5
\
.r/.
;/,
fei.. 1"
.U
V
9c
J^*^^'-
6(1.
.i ...
''^^f
,1V
« @
6-^
'/</iiie//ti /iff.i/ii/ii Jj'iisA. 2.('ril<'n .s<ir<(il)i /hi.ik. .1 C'nlfi i diiirii <j<'t/i iriat ii ni Hyii-'/'/i i(h/fi ftiisilhim Ulh ■^.Ch//t,.rrirr/iir/iim /tux/,-, fi (h/fi (i/'i/iirn llyir.r/i 7. CrihriceJifi rii/'a Afar Or// d'.Cri/i rri/>r,iriaBii.iA- .'////iitA-M <■///! fiii/r/ie/Jei .Utifi/e.r
Plate XIII.
396
Plate XIII.
Fig. 1
— 3 a.
— :tl).
— ;i c.
4 a.
— ib.
Oa.
(ib.
7 b.
A goiiozon'ciuin of ('.dlpi-liuni poiulcrosiim ((ioldsl!. X 2:t.
Tlic same gonozoocciuni. IVoni the basal sur- face. X 23.
Tbe same (•onozoa'cium, lateral view. X 23. A sagittal section thiougli a gonozodcium of the same species. The covering kcnozod-- ciiim and the distal wall transformed into an oieciuni arc seen d. w.). X 23. A gonozo(vcium and a corresponding covering zocrcium of (Uilcnaria (on the i)late Viltali- cclla) I'ormosd (Husk), The internal oceciuni is seen, and in both the zocecia the small, oval, infra-scapular chamber and the long, narrow, pedal chamber are seen. X 55. A gonozixccium and a corresi)onding cover- ing ziKccium of Cdtcndria fVilliilicelld) clc- Hiins liusU). X .').'■>.
A gonozo<ecium and a covering zofccium of the same species, lateral view. X 55. Three old zotccia of the same si)ecies, the aperture of which is on the point of closing. X 40.
A bi-zoiecial internode of Calcniirid i Villat.) fusai (Mac (lilliv. '. The aperture is partly closed. X 40.
A gonozoicciuni with appertaining daughter- zoncciuni of Ctilenaria fVittat.) cornttlit liuskX X 55,
A gonozooecium with appertaining daughter- zo(ecium of Calciuiriu (Vitlal.) coniiiln (Busk , from the basal surface. X 55. A gonozoircium of the same species, lateral view. The internal oiccium and the covering kenozocecium are seen. X 55. Onchopora on the plate CalweUki] ilcnkita .Mac (iilliv.), from tiie basal surface. The linger-shaped expansions of the distal wall are .seen, X 40.
T!\e pro.ximal end of a zo(ecium of the same species. X 75.
Oncbopora SincUiiri (Busk. In two of the zocvcia the operculum is open and the in- wardii^directed, angularly bent lateral parts of the vcstibuhim are seen. X 40. A zoa'cium with ooecium of the same spe- cies. X 40.
A sagittal section through an unlinished oa- cium. The cryptoc\st, which rises from the distal wall, is incorrectly drawn as connected with the membranous endooiueium, (see pi X.\IV, lig, IL'). X 40.
I-ig. 7 d.
— 7 e.
— 7 f.
— ■?«•
— 7h.
— 8 a.
8 b.
8 c.
9 a. 9 b,
9 c
— 9d,
— 9 c.
— !) f.
— 9H-
— Oh,
— 9 i,
— 9j-
.\ sagittal section liirongh an oieciiim of the same species. Here also the cryptocyst is drawn as connected with the cndooiecium, ekto — the ectocxecinm; endo — cryplocysl together with the cndooa-ciuni, X 40. An o(i"ciuni of the same species, lateral \iew. X 40,
An undeveloped oceciuni of the same species, from the frontal surface. X 40. An ofcciuni of the same species, from the basal surface. X 40.
A transverse section ■ through a branch of the same species. Two distal walls with ro- sette-plates and two compensation-.sacs are seen. X 40.
Calwellia (on the plate OnchopnrclUi) hicor- nisWyv. Th. The one half of the distal wall of the lowermost pair of zocccia is seen and also two of the internal o\al rosette-plates, through which the stalk-like proximal end of a pair of zoiecia is in coniinuuication with the wider distal part of another pair. X 40.
A transverse section through a branch of the same species, between the stalk-like proximal part and the wider distal part. A pair of zo(Pcia is seen from the distal end, and also the forked distal walls and four intersected stalk-like proximal ])arts. X 55. A transverse section through a branch of the same species, approximately tlirongh the middle of the wider distal part of a pair of zoiecia. X 55.
Oncboporella bomhyciiui liusk). X 40. A sagittal section throngii two zocecia of the same species with oci'cia, ekto — the ecto- 0(ccium, The cryptocyst removed, X 40, A sagittal section thrmigh two zoa'cia, fur- nished with radical librcs. The one descend- ing part of tlie distal wall is seen, X 40, Two zofecia of the same species with radical fibres, from the basal surface, X 40 A part of the margin of a colony, X 40, Zofccia of the same .species with developing occcia. X 40.
Transverse sections of two zocecia and of a kenozofecium. X 40.
The first beginning of an ocecium. X 40. Developing oiccium, a little older. Developing oiecium, in which the basal sur- face of the crvplocyst is almost formed. X 00.
^'. U./lt/.rfjf/f.Y('/f,Jjrf/o I Of/.
p/.xm
/ ft//fi/t//ii/u fiurii/crosi/rn Oa/r^/. 2. 1'MafifclIa /'or///os(i /Ju.tfc. .3.1'iU^Uic-. efeyft/ls Bu.s/,\ ^/. /}7/f///r /i/.irft Jliir 0/// ■ J iy//i-y//r ro/v/t/Ja //i/.rA (i CWlH-ellia' deri-f-a/nMac Gill . 7.(''fi/H:Stnr/fi/rii fitrsk. <^ O/ir/ityiorclln l/iroffi/x ll}/ir'/7/
■9. O/rr/to/i . l/Offf /f/frt//(f />*tf,vA: .
Plate XIV
398
Plate XIV.
l-iK I ■■'-
— lb.
— 1 C-.
— Id.
— 1
— 1
— 2 b.
— 2d
— 2e 2 2(
- 2 f.
Adeorrn tnotacfii .loliiist . Numerous marginal zoa'fia are seen, the frontal wall of which is still uncakified. X 28.
Four zoiecia of the same species. On two of the zod-cia the aviculariuui is re|)laced by an elongated cavity which opens by means of a round pore. X 40.
Three zoiccia of the same species, from the basal aspect, after removal of the basal sur- face. The primary aperture and the pro.ximal margin of the secondary are seen. X 40. Two gonozocccia of the same species. They are furnished with a similar cavity instead of avicularium, like the two zocecia in fig. 1 b. X 40.
An avieularian mandible of the same spe- cies. X 100.
An operculum of the .same species. The somewhat more chiliuized transverse oval part is the portioEi of the operculum, which corresponds with the' secondarv aperture. X T.-i.
Adconella scrrata n. sp. In a single zotecium the aperture is covered by a calcareous plate. X .')5.
Two gonozoa'cia and an independent avicu- larium of the same species. X .'>.'>. Three zoa'cia of the same species, from the basal aspect, after removal of the basal .sur- face. X .'i.T.
A mandible of an iudepcndcjit avicularium of the same species. X 40. The mandible of a dependent avicularium, more highly enlarged. X 140. The operculum of a gonozonecium of the same species. X 140.
The operculum of an ordinary zocecium of the .same species. X 140. Bracebridgia pi/riformis (Mac Gilliv: X 40. Foul- zoiecia of the same species, from the
after removal of llie basal sur-
basal aspect, face. X ").'). Fig .'t c. A portion of the margin of a colony of the same species with two avicularia. X 5.').
— ;i d. An avieularian mandible of the same species.
X 140.
— 3 e. The operculum of the .same species. X 140
— 4 a. Adconella JelUjac n. sp. In two ot the zoce-
cla the pore of the secondary aperture is not yet constricted. X 40.
— 4 b. Two opposite rows of zocecia. lateral view.
In the two adjacent median, longitudinal belts numerous less distinctly drawn) uni- jjorous rosette-plates are .seen. X 40.
— 4 c. A zo(ecium and a gonozorecium of the same
species, showing the primary aperture. X 40.
— 4 d. An iudei)endent avicularium of the same
species. X 40.
— 4 e. The mandible of the ludepciidcnt avlculail-
um. X /.'>.
— 4 f. The mandible
um. X ion.
— 4 g. The primarv aperture of llie
X 7,').
— 4 h. The operculum of a gonozocecium of the
.same species. X 100.
— 4 1. The operculum of an ordinary zo(Cclum of
the same species. X 100.
— 4 J. Aflconclld piicima-a. n. s]). (not A. Jcllyae).
I'ppermost a single zo(Ccium with the pri- mary aperture. X 40.
— 4 k. I'he operculum of a zoa?clum of .same spe-
cies. X 200.
— 5 a. Adeoncllopsis roscinoplwra (Ueuss). X 55.
— 5 b. The same species, from the basal aspect.
after removal of the basal surface. X 40.
— 5 c. The operculum of the same species. X 140.
— 5d. An avieularian mandible of the same species.
X 100,
if a[i independent avkulari-
saTue species.
(t . 1/ U /.f t/ 1 //.■:<■ ff. /hf/a : Otl
/VA'/l'
Q
///.
^^ <j-Sr
,..M^»n» ,ns/r/,os,i ./„//. -.'.U/eone/ia s,'rra/<r ,>..y/'. .J. /Jr»ce6r,/{y,a f„yrifor„„s J/arO./l. ^, .l,/eutir//ri Jr//iy<e n.sp . .i Jf/>-o,/r//r>/,.ifS rosc/rKYr/iora fieriss .
Plate X\.
4on
Plate XV.
KiR. 1 a
— 11)
— 1 f
— Id
Vrceolipora nana Mac Gilliv. , witli open operculum. The li^uie only shows the strong- est of the longitudinal ridges, which keep the covering membrane stretched. Three Od'cia are seen. X 40.
Two zo(ecia of the same species with ocrcia, from the frontal surface. X 40. \ sagittal section through three zoa'cia of the same species with o(ecia. The covering membrane, the lowermost part of which represents the ectood-ciuni, is too thick, as it has been drawn with a double outline to make it distinct, (look V\. XXIV., Ilg. 11.). X 40.
A zoiecium of the same species with oeecia, from the basal surface. The uniporous ro- sette-plates of the basal surface and of the distal wall are seen. X 40. 1 e. A trausvcr.se section through a branch. Two zoa'cia and three of the ridges, which kee]) the covering membrane stretched, are seen. X 40.
1 f. .\ transverse section through the pro.vimal
part of an oiecium and through a portion of the adjacent zoa'cium. The endoo(ecium is seen innermost and on each side of its aperture one of the trapeziform i)rojections which contribute to keep the covering mem- brane stretched. On each side of the cover- ing membrane intcrnallj' is seen the collar- shaped ridge which surrounds the proximal part of the occcium, and lowest <lown the separating wall towards the adjacent zooe- cium. Outside the eudoo(ccium the distal wall with its roscttc-plates is seen. (On account of incorrect shading it seems to be arched). X S.").
2 a. Eulhyris obtecia (Hincks). On tlic marginal
zoa'cia the peculiar processes are seen, by which the covering membrane is kept out- stretched. X 40.
2 b. Four zo(ecia of the same species, from the basal surface. Besides the rosette-plates a number of filiform, calcified elongations are seen. X 40.
2 c. .\ sagittal section through two marginal zo(C- cia. The internal lateral processes arc visible and also the connections between the cryp- tocyst and the covering membrane. X 40.
2d. Sagittal section through ordinary zocccia. X 40.
2 e. The processes of the lateral wall, from the uter surface. X 40.
l-ig. 2
— ;i:
— 31
— 3 (
.■jb.
— (i a
Oh,
fi c 7 a,
Operculum of the same species. X 10(1. MUroiiorclla niari/inalu (Kraussi. X 40. The distal end of a zoan'ium of the same species. X 100.
Four zorecia of the same s|)ecies, from the basal surface. In addition to the marginal pore-chambers each basal, zixccial surface shows a rosette-plate and an opening for communication with zodcia in the opposite layer. X 40.
The operculum of the same species. X 140. Hadical fibres of the same species. X 40. A vibracular llagellum of the same species. X 7.-..
Microporella flabellaris (Husk). X 40. The distal end of a zixecinm of the same species. X 40.
The same s])ccies from the basal surface. Besides the basal wall of the porc-cliambers the small triangular basal surface of the vibracular chamber is .seen lowest down to the right on the four zon?cia. On some zoce- cia the basal surface shows a rosette-plate, and on others an opening corresponding with a roscttc-platc in an opposite zoiecinm. X 40.
Hadical lihres of tlic same s])ecies. X 40. The operculum of the same species. X 140. The aviculai'ian maudihlc of the same spe- cies. X 5,5.
The fii'st three zoiecia of a colony of Micrn- jiorella ciliala (Palla.s). The original aperture of the primary zoiccium, which is surround- ed by spines, is almost closed to a pore. X .'iS.
The aperture of Microporella ciliala. A well- dcvcloped vestibular arch is seen and the supporting beam is furnished with a pair of lateral teeth. X 200,
Microi>orell<i ilecorala (Heuss). The zod'cium is furnished with three distal pore-chambers, and the curved belts on the (xecium, at the base iif which arc seen the line pores of the cudoocccinm, arc canal-like cavities between the cndooiecium and the distal calcified part iif the ectooiecimn. Between these canals, which open through a circle of ])ores, the two layers of the ocecium have united. X 40. A portion of the occcium more highly mag- nified. X 75.
An opercnlum of the same species. X 100. The aperture of Mirropiirrlla Maliisii (And.). X 100.
(f: U./^./,i'oi ii.ienjirijo ; c
PUT.
/. i'rcfo/i/iora. nana ALdilL .'. Fat/it/r,s ohiecia Hincks. J.Micro/ioreUa nuirfftruUa A'rauss. 'i .tticrop riahi'lhiris Busk. 5. Microji- cilutlt, Poll. G. Microp . drcorulu Hcuss 7 Aficrop. MahisU /lud.
Plate XVI.
26
402
Plate XVI.
— 1
— 2
— 3 b.
I"i(!. 1 :i A s:i);ittal section tbioiigh a colony of llas- ii'vUiii coronala (lieussi. Three on?cia are seen X 17.
All operculum of the same species. X 140. A sai^ittal section Ihroufjh Uasivellia aiis- Iriiliensis (Busk. Tlie four lowermost zore- eia with od'cia. X 17. All opereuluni of the same .species. X 75. Tiibuccllaria hirstiUi (l.amx.). The four lateral zoiecia with |)eristoniial oiecia. X 17. A saj^ittal section tlirough the same species. The two lowermost zoa-eia with ooecia. X 23. Oiiereulum of the .same species. X 75. A separatin;; wall with rosette-plates, the position of which is at the proximal end of each of the thrcad-sliai)ed apjicndages. X 200. A part of the surface of a zoiecium of the same species. The ascojiore is .seen distallv. X 75.
Tubiicellaria opuntioiiles (I'all.). Five occeia are seen. X 12.
A sagittal section through the same species. Two od'cia arc cut through. X 23. An operculum of the same species. X 75. The same species. A ))art of the surface of a zooecium. The aseojiore is seen distally. X 55.
Tithiporclla imifinirostris (Mae Gilliv.). Two peristomial ooecia arc seen. X 23.
— 3 I
4 a — 4h
— 4 c.
— 4d
I'ig .') 1). The same species from the basal aspect after removal of the ha.sal surface. Two oceeia (which are however not correctly shaded) arc seen, and the three zotreia show a distinct vestibular arch. X 23.
— 5 e. The same species. A part of tlie surface of
a zooecium. X 55.
— 5d. A sagittal section through the same species.
.\n occcium is seen pro.ximally, and the two zoiecia show a vestibular arch at the be- ginning of the peristomial tube. X 17. LeUythopora hystri.r Mae (iilliv. Three ooe- cia are seen. X ()5.
A sagittal section through an otccium of the same species. X 23. An operculum of the same s|)ecies. X 55.
— 7 a. A sagittal section Ihrougli LeUijtbopora stel-
lata Pusk'. Two ooecia are seen. X 17.
— iS a Eulhijroides Jellijac n. sp. X 40.
— X 1). The distal end of a young zooecium of the
same species. The frontal surface is caleilied right up to the operculum. X 75
— cS c. The distal end of an older zocccium in which
a resorption of the chalk has taken iilaee jM'o.ximally to the operculum. The two hol- low s))ines are formed, which cover the entrance to the comi)cnsation-sac. X 75.
— 8d. An o])erculum of the same species. X 100.
— 8 e. An avicularian mandible of the same spe-
cies. X 40.
'/ ff./,//j//isi'ii, /^n/o\o(i
/VJT/.
r //ri.-,rjic//i<i f/rarifts f.n/tij- L'.//iisoj. eiits/rrt/fcf?-iis /jii-s/r .'i.7'ti/>uce//aria hir.yutuJ.orrix 'f '/iilmc apjtrUioifles /'a/l. 6. 'f'uhiic nixit^ruro.Hris Mac Gill. &■ f.eJcyUiOfmra Ju/slrij- Mar Cn// 7. /.fir. slr/la/<i ^iislr S. ^i/l/i-i/ryicryi-.t efiisriyialis Miislr
Plate XVI 1.
26*
404
Plate XVII.
V'tfi. 1 :). Eschitrella <li(iphaiia (Mac Gilliv.). A young colony with tlie primary zoa'ciuni. Pore- ilianibcrs are seen on tlirec zotpcia. X 40.
— 1 I) Two zod'cia of tlic same species. Pores are
seen inside the marginal ridge. X 40.
— 1 c. Tlie same species. Tlie distal liall' of a zoie-
eiuin, the frontal wall of whieh has been removed, so that the highly developed vesti- bular arch may be seen and the rods by which it is connected with the lateral walls. X 55.
— 1 d. The distal half of a zoiecluni of the same
species, seen from the basal snrface after removal of the basal wall. The basal wall of the vestibnlar arch is seen. X 55.
— 2 a. Escharclla iilnissicola (Norman). A sagittal
section through a zocrcium with oa'cium. The oopcium is surrounded by a kenozoce- eium, the frontal wall of whieh seems to be united with that of the ocL'cium. X 40.
— '1 b. The .same species, from the basal surface.
Three occeia are present, the surrounding licDozoopcia of which are furnished — like the zooccia — with pore-chambers. X 17.
— .la. EschiircIId imniersu I'lem.i var. The basal
portion of the endoo<ecium is surrounded
by the crvptocvst of the distal zocccium.
X 40.
Escharoides ])rucslans (Hincks). X 40.
The same species from the basal surface.
I'ore-chambers. X 'i.'i.
Escharoides saiiroiiloss<i n. sp. X 40.
The same species, from the basal surface.
The vestibular arch with its thickened
margin is seen. X 40.
— 5 c. The distal end of a zocccium of the .same
species. Pro.ximally to the sjjines the vesti- bular arch is seen. X 55.
— 5d. An avicularian mandible of the same spe-
cies. X 75.
— 5 e. A distal wall of the same species, with pore-
chambers. X 40.
— 5 f. Three opercula of the same species. The
smallest is not from the same colony as the two large ones. X 75.
Fig. 0 — 0
7 b.
— 8
— 8
8 c.
— i)b
— !) c.
10
1 0 1).
10 I
Exochella loncjiroslris .Jullien. X 55. A zod'cium of the same species, from the basal aspect, after removal of the basal surface. The primary aperture is seen and also the secondary and tertiary; further the vestibular arch X 75. Exochella lohata n. sp. X 75. The distal end of a zixccium of the same species, from the basal aspect, after removal of the basal surface. The vestibular arch is seen in addition to the primary and secondary apertures. X 75. An operculum of the same species. X 140. Exochella zelanica n. sp. X 76. A zocccium of the same species. Three pore-chambers are seen. X 75. .\ zooecium of the same species, lateral view. The strong rostrum proxinially lo the aperture is seen and also the maigiiuil ridge which is very prominent, running out into lobes. Inside the ridge porc-cauals are seen. X 75.
Exochella triciispis (llincksi. X 75. The distal end of a young zocccium of the same species, whieh shows the primary aperture Three pore-chambers. X 75. The distal end of a zonecium of the same species, from the basal aspect, after re- moval of the basal surface. The vestibular arch, the primary aperture and the thiee coalesced teeth of tlie secondary apeiture are seen. X 75.
An operculum of the same species. ,X 140. .\ multiporous rosette-plate of Sniilliiui I'allasiana (Moll.). X 350. ■A schematic longitudinal secticm through a multiporous rosette-plate. To the right is seen the pore-ring.
A schematic longitudinal section through a |)orc-cluimber To the right the ol>lic|ue wall on which the rosette-plates are situ- ated
b
(^
(i A/M/.i'Diii.irri, /j'r/yoiOf/
/. /:Wr//,/n'//ci (hafihtititt Jfac (Jill. 2.Escfi. nhu-;sivoUi Sorifian. 3.Bsrh.irnrti.crsa /-'/t'/n.t/nr. ft.PcrLKtorrwfht rirn'sta/us Ifinch:^ .>./'*'/: xanrofjlti.Ksu n Sft . (J. Kj'ocJwHa- /onc/iro.ifn.s JuUi<'fi 7./\j'4>ch luhat^i- n.s/t,. S. StrocJixr tum tut- /{..syr. S. Kcoch. /.ririis/ttW //t/u-Ai\.
fO fi'o.svffihulf Oft PifrrJk'fttn mer' .
?
Plate XVIII.
406
Plate XVIII.
Kin
1 a. ICscharinii pes an.tcris (Siiiitt\ The distal end i)f a zdcvcium with (icpcium. X 75. The distal iiid of an ordinary zoceciiim X 75.
An opcrenUnn of llic same speeies. X 75. KsclKiriiKi Diitcrtrfi (And.). The vestibular areli is seen and also tiic distal inarj^in of the hinge teeth, wliieli for the most part part are internal. X 75.
The same speeies. The distal end of a zoo.-- einm. from the basal aspcet, after the basal surfaee has been partly removed. The liif^h hinge teeth are seen and also the vestibular areh and the proeesses springing from the latter. X 55. An opereulum of the same species. X 100.
3 a. Schizoimrella {Sti/lopomoj longirostris Hi neks. X 23.
The same speeies. A portion of a colony with superficial budding. X 23. A zod'cial aperture of the same species X 75.
A zooeciuni of the same species from the basal surface. X 40.
.\n operculum of the same species. X 100. An aviculai'ium of the same species. X 75? An avieularian uKuulible of the same spe- cies. X 75.
Schizoporclla (St.) sjionyiles IPallas'. An oce- eium is seen, the frontal half of which is cut away. X 40.
The same species. .\n od'ciuni from the pro.\imal enci and distal walls with rosette- plates. X 40.
Operculum of the same species. X UK). The same species. ()i)ereulum of a colonv from Java. X 100.
5 a. I'clniliii jiipoitiai \ Husk). The lowermost zoreeium to the left shows a hollow, from which the whole (Kcciuni has been removed; the uppermost to the right shows on the other hand an od'cium with the frontal wall removed. X 40.
5b. An operculum of the same species. X 75.
1 b.
2 b.
2 c.
— 3 b.
— 3 c.
— 3d.
— 3 c.
— 3 f.
— H'-
— 4a.
— 4 b.
4 c. 4d.
I'ig (i a. I'orclla (?) corniita n sp. The ocecia are furnished with acro])etal hollow spine-like proeesses, X 40.
— Ob. An o|)erculuni of llie same species. X 75.
A more correct figure is seen on Plate XXII, fig. 11 a).
— 7 a. Arthropomti Cecili And.) A developing
ooccium. X 40.
— 8 a. I'orclla margnritiferii Ouoy & (iaim.'. In
the bottom of the avieularia the primai-y ribs of the frontal wall are seen, lioth the 0(ccia and the avieularian chambers show concentric deposits of chalk. X 55, !) a. A sagittal section through a gonozoieeium of llippolhoa liijalina L. The oa'cium is surrounded by a kenozoircium.
— 10 a. A sagittal section through a gonozoiecium
of Chorhoponi Uronf/niarti Aud. The ote- cium is surrounded bv an avieularium. X 55.
— 1 1 a. Haploponid imprcssiuii And.) from the
basal surface. The zo(Ccia and the keiui- ziMccia surrounding the ocrcia arc furnished with pore-chambers. X 40.
— 12 a Smiltina akaroensis n. sp. The margin of
the ooeeia is furnished with an oiecial cover. X 55.
An operculum of the same species. X 100. FntI'dllolhecd tivailnitu (Mac (iiUiv.. .Si.\ dilTerent zoiecia take part in the formation of the o(vcium figured. X 23. The aperture of a zoa-cium of the same species. X 75.
An operculum of a gonozo(ecium of the same species. X 55.
An operculum of an ordinary zoircium of the .same species. X 55. .\n avieularian mandible of the same spe- cies. X 75.
EurijslomelUi foniminiiient IliucUs Two gonozo(ecia and an or<linary zo(ecium. X 40. The same three zoiecia, from the basal surface, which has a large uncalcilied cen- tral part. X 40. 14 c. A sagittal section through a zocecium with (MEcium. The ocrcinm and the covering kenozoa;cium are seen. X 40.
|
12 b |
|
13 a |
|
13 b |
|
13 c. |
|
13d. |
|
13 e |
|
14 a |
|
14 b |
(/ . U /)' / cuiftscu , Hri/o : off
I /"
i^
r
lJ
fm'^ft
^^JP
(0 Oil
r
f^\
r\i
3
12..
fi
i',,i-i.'V-«|
Jl
'J."
'fii
*^r5aK
J:
«/.
-^
.*)_
'S^^Y'^
/y.i7///
■^^
~1 c
13
^.
.^^^Sir-.
!tf
\'"
^
I
r<',#:'"^.
m^%
J'V
/p
n
"• w
Ih.si/iiinna fif.l rtll.siTls Siilill 2.Ji.s<ll /^illi-ilrri .liiil. "i. Sll/lo/lorini laiii/iliixlris Jlinc/,:s- '/S/i/io/li/l/r.t /'nil 'i./.r/iliil in . /"/'""Iff liiist,- (> ./.rfi' rorriiilii n.s/i 7 .Irlliro/ioiii'i (Willi .liiil Jl/'orrllii iiKii'tinnlirriri Oiini/ ,i' Iwim. .') Iliiifiolliaii /ii/iiliiin /..
lO C/iori-.ofiorn /iioiii/iiiirlii .linl II //n/ilnfioiri<i iiiifiri'.'iXii hiil l2Slnillinii niiirnriisi.\ ri i/i 11 .Sin illirKlnilii .llm- f/ill
I'/. /utrN.\'linii rl/fi /firiitflrfiifffiul //ttif7.\
Plate XIX.
Plate XIX.
I"if(. \ .\ rniiKislaja ivniislit iNi)iman\ A zocvcium Fi^. >S li- mikI two (Iwaif-zod'cia. X 75.
— 1 li Till' samo species, from the basal siirl'ace. ,
Two oii-eia are seen siirniuntlcd l)y dwarf- — i) a. zocrcia, which, Hke the ordinary zorecia, are fnrnished willi pore-chambers. X 40. 1 c .\n opcrcnium of the same species. X 149.
— 1 (I. .\m operculnm of a dwarf-zocccium. X 200.
— 2 a. Disco/iora piironclla (Alder. . \ portion of
tlie marf^in of a colony witli all the zooccia undeveloped. On the oldest zodceia the dcvel- — i) b. opmeiit of the a\ icnlaria lias just bcgnii, lint the frontal surface of these is still a cimtiiuious membrane, and on four zod'cia I ID a
the frontal surface still consists of a row of independent calcareous jilates separated by sutures. Distally to these plates is seen -- 1(1 b. a dark curved line, the j^rowiujj end of the fold which encloses the cryptocyst, and the internal layer of which becomes the exter- nal wall of the compensation-sac. X 2,3. — 10c.
— 2 b. .\ sagittal .section Ihrongli a zo(Cciuni of the
same species to show the compcnsation-sae (es\ The above-mentioned fold surrounds — 11a. parts of the decalcilied. broken cryptocyst i — 12 a (cr.). X 75.
— li a. The zocteia of Smillina jiroiiiiiqiia (Smitt), I
from the basal surface, which consists of a I — 13 a. number of striated plates meeting in sutures. X 4(1.
— 4 a. Snullina Sinitli Kirchenp. A developing i — liib.
o(ecium. The ectooiecium still consists of
two separate halves. X 40. — 14 a.
— 5 a Smillina palnxtla (Sars), var. A developing
od'ciuni. X 40.
— 5 b. The basal surface of a zocccium of the same — 15 a
species. Plate-mosaic with centres of calci- fication. A multiporous rosette-plate. X 40. — 15 1)
— (i a. X zoiecium of Sniillinii Lanshoroi'i (.lolinst.)
with oa-cium. An occcial cover is seen, which — 16 a paitly appears in the margin of the zore- ciiini partly forms two projections distally to the aperture. X 40. r> b .\n od'cium of the .same species, through — 17 a the broken ectocicium of which the ciido- ou'cinm is seen. X 100.
7 a. Two (Hccia of Smittinn Irispinusa, var. nicul-
Ictna n. with a hood-shaped oiecial cover. X 40
8 a. Some zcxucia of I'liisira seciirij'rons (Pall.)
after boiling in potash, to show the process of calcitication of the basal wall I'see pages 4-5). X 33.
«li— f. Sagittal sections through a series of devel- oping oa-cia of the same species (see page 57). X 40.
Kg. A very early rudiment of an otecinm of the •same species seen partly from the proxi- mal end. The distal curved line is the line in which the distal wall joins the frontal membrane (fig. 8 b\ and the bilobatc part .seen within the operculum belongs to the horizontal part of the distal wall. The rounded sinus is the beginning of the ro- sette-plate. X 40.
— 18 a.
— 18 b
— 18 e.
— 19 a
-II. .\ series of (kvclopmcnlal stages of the endoocrcium of the same species, seen from the surface. X 40.
Some zocecia of h'liislrii (Flustra fnliiiceti L., from the basal surface, after boiling in po- tash. The distal wall with its rosette-plates is seen and the composition of the basal wall in small plates see page (i). .A very tine striation parallel to the distal lines cannot be seen in this figure. X 40. Two zotrcia of the same species after boil- ing in potash. The lateral wall's composi- tion of small plates is seen. X 40. .\ transverse section through a branch of Flustra (Spiralis) ilvnticnUdu Husk, cr. : cryptocyst. X 55.
.\ sagittal section tlirongli an avicularian mandible of the same species, to show the internal cavity which corresponds with the vestibular cavity in the o])ei'ciilum. A portion of the basal surface of the same s|)eeies, to show its composition of cell-like small plates icell-mosaic \ Inimers. Operculum of l-'liistra pisciforniis. X 23. .\ transverse section through a branch of I'liistra Flustra) carhacea Sol. cr. : crypto- cyst. X 40.
An avicularian mandible of Sarsipaslra ahyssicola (Sars. , to sliow Ihc internal cavity. X 23.
A transver.se seeliiin through the same mandible in its middle part. X 23. .\ trans\er.se section through an avicularian mandible of an Onijchocella species, to show the mandibular cavity. X 40. The avicularian mandible of Snilin'lla plaijiostoma lUisk. X 75. .\ transverse section through the end of the same mandible. X 75. Pore-canals of .1/yr/oroiim suhnracile d'Orb. Kacli of them contains an eiidosarcal cord and is, at its |)roxinial part, furuished with a unii)orous ro.sette-plate. Immers. llasau'llia aiiriciilala (Busk). Kach of the two-layered stalked, developing otrcia is placed in a hollow. X 40. A sagittal section through .some o(eciiim- bcaring zoacia of Sclerodomiis dcnliciilnlus (Husk\ The avicularium is seen on the internal surface of the peristome and the plate originating from the distal wall. X 23. .\ sagittal section through a zo(ecium with od'cium, more highly magnilied X 4(1. The same species. As a portion of the frontal surface has been ground away, the Hat proximal part of the (Kccial frontal surface is seen and the broadened crenul- ated margin of the plate originating from the distal wall. X 40.
Discopora plicaki (Smitt.). The distal of the two angular lines is the growing cud of the fold or outpushiug formed by the frontal membrane and enclosing the cryp- tocyst whose growing end forms anotlier angular line. X 40,
(i M R.!.*'iHii.-:cti . Ihftox
PIX/X
/ 7h^/ios/ff/ri otrtUAfa Xori/i ^. f '/ft ho// it /ft p(ti>o/tell<t .i/t/. ,'i. P.srlidon tisirtt firofttttaott Stmif. ^t. P. MmiUt A't rr/t f /t /i . -'. /* fifif/Hd /ft Sftf.s'. ftftf- (iSfnt/ftntt f.ftnr/.s'/mr'oott .fo/iiist. 7. Sriini/Zeitia rt.s/i- fi. /''Itt.s/fft svriiri rt'ons Pa//. f/F. fo/iacfa I. f<>./'*lenii'4ii/,tf,i /ins/.-. //./•'. /I i.uiforrrii.v /his/,-. f'J F.tfirhttrvti Sol . /J. /•' (i6t/sstro/ri Sftfs /^. On ifr/itnt/Zti s/i . /J f'atr/t/r,//ft
fi/itfftosloi/tfi /iiisi- /(>'. A/tfifo 1 ontti sn/>f//rtri/c tl' Of/y /7 „//itstrf//t/i " fttit'tctt/tilu //lis/,- tX. .Sc/er-it,litrttns Jcn/triil (titi.v AV/.v/
/// !i/uiinn/iif.stontr//a fi/irtt/ii Sr/ii//
Plate XX.
410
Plate XX.
1 b.
— 1
— 1
Fig 1 a. A zoccciuin of Siiilicelhi iirnuld (M;ic Gilliv.). The IViK'stiii- of the sternal area show a dis- liiut ervptdcvst. X ">,">.
A gonozoceeiiini frciTii the hcmlal surl'aee. X 17.
The same Kono/ocLcium, lateral view. X 23. The .same Honozixeeium, from the ha-sal sur- faee. X TA.
The median ehambers from the distal part of another Koiiozoceeium. The downwards direeted point eorresponds with that seen in fin. 1 1). X 10.
.A lii-zod'cial internode of Sciilicclhi Wilsoni (Mae (iilliv.i. m: mother-zoteciuni. d:daugh- ter-zo(i'einm, 1: the siipra-seapidar eliamber, 11: the seapnlar eliamber, 111: the infra- scapular chamber, 1\': the pedal chamber (fig. 2b\ X 40.
A bi-zo(eeial internode of the same species, from the basal surface, less highly enlarged (see 2a\ X 23.
A bi-/.o(ccial internode of Scuticella marga- riiacea (Husk). (Compare with tig. 3 b\ X 55. A l)i-/,o(ccial internode of Scuticella marga- rilncea lUisk , var. li.ssurata, n. For the letters and luiinbers see e.\i)lanation to fig. 2 a. X 55.
A gonozoa-cium of the same form. X 40. \ zoieciuni of Sciilicclla maciiUila (lUisk) wrongly indicated on the I'late as Cnt. ven- Iricosci). X 40.
A zod-cium of the same species, lateral view. Besides the scapular chamber the iufra- scapular and the pedal arc also seen, (on the Plate indicated as Cttl. venlricosa). X 40. A zod'cium of Sciilicella iwntricosa (Busk), (wrongly indicated on the Plate). X 40.
3 a.
3 b.
3(
4:
4 b.
Fig. 5 b
IJa.
lib.
lie. 7 a.
8 b.
|
9 a. |
|
10 a. |
|
10 b. |
|
11 a. |
|
lib. |
|
11 e. |
|
lid. |
|
11 c. |
|
11 f. |
.\ bi-zorecial internode of the same species (see the cxphmation to fig. 2 a). X 40. (wrongly indicated as 5 a). A zotrcium of the same species, lateral view. The scapular, the infra-scapular and the pedal ehambers are seen. X 40.
The sternal area and the aperture of f.'os/i- celhi cnspklata n. sp. X 75. The same species. A zoa'cium which term- inates a branch originating from a daughter- zo(ecium. X 40.
A gonozocecium of the same species. X 40. The sternal ;irea and the aperture of Co.'s/l- cclla solitid n. sp. X 75. A zotecium of Coslicella bnxldlti (liusk\ (from Port Phillip). X 75. A bi-zotecial iiitci'Mode of the same species (from Twofold Bay). See the explanation to fig. 2 a). The long internal, sternal sinus can be seen. X 75.
A gonozocecium of (losliccUa benccoslala n. sp. X 55.
A zocecium of C.kwiporelUi aiirila i Busk). X 75.
A gonozocecium of the same species. X 55. A tri-zonccial internode of Cnlpidium or- naliini Busk. X 23.
A tri-zotecial inteinode of the same spe- cies, from the basal surface. X 23. A tri-zooecial internode of the same spe- cies, from the distal end. X 23. A tri-zo(ecial internode of the same spe- cies, lateral view. (.See the explanation to fig. 2a\ X 23.
A l)i-zo(ecial internode of the .same spe- cies, from the basal surface. X 23. A bi-zooceial internode of the same spe- cies, from the distal end. X 23.
II M R Itcvinsen , linjoxx<a
I. CaUruc&LLa. umula Mac COL. 2. CcUen.^ mCsorU Mac Gill. 3 CaUiv. mar^aritacea Busk A.CcUen fenincosct Husk.. 5 Ccdart. maailaia rvs/t. &■ CasttceUa cus/ticUita n-Sfi- 7. Costic
voUda /ix/i. SCostlc kasUUa, Busk. 9. CosUc. benecosUrIa n.s/t . lOCLaoLficreUa auHla
Mac CM 41 (hljiidiuin r>r/ui.tn>n. Busk.
LcCi.^.u-z aci
firUmd. ij) Dst ircHnshiyslct UtaiL
C Corpus IUa .
Plate XXI.
412
Plate XXI.
clKimber is ci\ iiulMi'iiim.
li I". 7:i.
7 1).
l-'ig. 1 a. Catenariti mi I lie l'l:ite VillittitclUi corniila Fi^ (Bu,sk\ III till' l)i/(i(i'cial intt'iiKide the niotli- cr-zoa?cial, small, oval, iiifVasiapuhir i-liani- ber is seen (in Hie houiitlan lietwceii the mother- ami the (laufihtei-zocveium. X 5.").
— '2 a. Catenaria Villalicclhi) I'leyans (Husk). The
siipra-sea|nilar, the inlVa-.sea pillar and the pedal ehamhers arc .seen. A honndary cham- ber (m. III.) between the mother- and the daughter-zod'eiiim. X 55. - .'i a. Calvnoria formosa (Busk). The same eham- bers as in lij>. 2 a. X 40.
— 4 a, I'terocella aliiUt (Wyv. Th. The iiKilher-zou;-
cial, lissure-like iiil'raseapular seen proNiiiKillv to the small
X 40. " — 7 d.
."> a. A /oreeium of f.'(///)ir/ii/;;i /)o;i(/(r«si(Hi (ioldst. The internal eiyptoeyst plate is seen and a strong crvploevst formation in the live fene- str:e. X 55. " — 7 e,
— 5 b, A zoa'cium of the same species, lateral view. — 7 f
The supra-scapular ehamber is seen and also
the infra-seapular and the pedal. X 10. — 8 a
— 5 c. .\ bizoiecial Internodc of the same species,
from the basal surface. The upi)ermost tri- — «b. angular cavity is the aclzoceeial supra-.scap- ular chamber of the mothcr-zuiecium. To the — .S left is seen a supra-scapular, an infra-scap- ular and a pedal chamber; to the right the — <Sd, pedal chamber is on the other band not vi- sible; the infra-scapular is on this side divided into two. X 40, — 8 f.
— 5 d. A zoa-eium of the same species, from the
basal surface. The sufra-scapular and the — 8 g. infra-scapular chambers are seen. X 40.
— 5 e. A bizooecial internode, from the distal end,
X 23. — 9 a.
— 6 a. Strophipora Ilarveiji iWyv, Th,). The supra-
scapular and the infra scapular chambers are seen. X 40.
— 6 b. A bizooecial internodc of the same species, — 9 b.
from the basal surface. The four pedal cham- bers arc seen, X 40, — 9 e.
— 6 c. A zooecium of the same species, from the
frontal surface. X 40.
— 6d. A zocEcium of the same species, from the
basal surface. X 40. — 9d.
— G e. A zotcciuni of the same .species, lateral view, — 9 e.
X 40.
.\ bizcxccial internodc, IVcim the disUil end. X 55.
llippoiboa iinntilaris (.Moll), with oiecia. On the boundary between the zoa'cia in the pro.vimal row porc-cbamhers are seen for communication with eventual gonozod'cia. X 23.
The distal end of a zocvcium of (lie same species, X 75.
A zoiecium of the same species, lateral view. Three boles are seen for conimnnication with tiie pore-cbanibers in a neighbouring zod'cinm and two pore-chambers for the communication with eventual gonozocccia. X 55.
A zotreiiim of Hie same species, from the basal surface. On each side of the angularly bent distal wall the entrance to a large pore-cbambcr is seen, X 55. The operculum of the same species. X 75. Opercnlum common to the gonozod'cium and oo-cium >; 'JOO.
Ilippolhoti lorntilii Husk;, var. holnxtoiiKt n. X 40.
A zoicciiim of the same form with oiceium. lateral view. X 40.
A zoiL'cium of the same form, from the distal end. X 75,
.\n operculum of the same Ibrm. X 200. Four zoircia of the same form, of which two with orecia. X 40.
Operculum common to the gonozoireium and otecium. X 75.
A zotecium of the same form, lateral view. The acropctalous spine has an internal sep- tum. X 55.
An ooecium-bearing zooQcium of Ilippothoa cornuta (Husk), var, aporosa n. lateral view. The acropctalous spine has two cavities divi- ded by an internal se))tum. X 40. .\ zou'cium of the same form, from the dis- tal end. X 75.
Three zooccia of the same form, of which two with Odcia. The latter are distinctly visible through the surrounding kcnozocccia. X 40.
An operculum of the same species, X 200. Operculum common to the gonozoircium and ooccium. X 200.
G.M. R.Levuisen, Sryozoa
FLJM.
\
'i.Viitaticclla cor/ucta. Jiusk. 2.V"o1y. elcc/ans Bitsk.. 3.Vvi>. fornvosco Bit^k. 4 F/^croceUa^ cdata Wji/v.TIv. 3. Calp,idlurrh pondcrosu-irv Golds t. &. Sbroj-ifvLpor-a. Uarueyv Wt/v.Th. 7-JRjvp,othoa anjtuictrU Moll. 8.Jfi/v. cornu-tci- Biisk.-var ho I OS to ma /z . .9. Hin. corrLUta. BiL,?ki i?nr. apoi-oscx n.
\foinsen. det-
nrvitad' iy Det Jfo^nsbe/yjiKe jEtait.
C.Corcits Htfi.
Plate XXII.
414
Plate XXII.
Fig. 1 a. FUisIra (Rctipiislra' reticulum Hincks. X 23.
— 1 b. A zod'ciiiin of Uio .same specks with ofrei-
um, lateral view. X 40.
— 1 c. The same species from the basal surface.
The uppermost /.(Hreium in the central row is lurnishetl with an (Hceium. X '2-i-
— 2 a. Flustra Helipusira eriliriformis Husk), fvom
the ba.sal surface. The two uppermost zou;- eia with o(ecia. X 40.
— 3 a. Otniclwrclhi sp. The two uppermost zofccia
with od'cia. X 40.
— 3 b. A zod'cium of the same species with ooe-
cium. In the covering membrane of the aperture is seen a simple chitinized oper- euhun, and in each of the two sinuses of the aperture the end of a parietal muscle. X 55.
— 3 c. The same species. A zoa-cial operculum,
above which an o(ccial operculum. X 7o.
— 3d. An aviculariau mandible of the same spe-
cies. X 40.
— 4 a. F.leclni angulalii n. sp. X 40.
— 5 a. Mcnthranipora liiuosa Waters. X 55.
— 5b. The distal wall of the same species with
the peculiar spine-like processes. X 55.
— 5 c. A spinc-likc process more highly magnified.
X 200.
— G a. iVc///(i simplex r?; Busk, from Mauritius.
The distal part of the ocecium is furnished with a cryptocvst belt. X 40.
— 7 a. Thtiltimoiiorcllti cinclii Hincks'. X 40.
— 7 b. The saiue species, lateral view. The distal
wall and the one opesiular outgrowth are seen. X 40.
— 7 c. A transverse section through a zoa'cium,
distally to the two large swellings and view- ed from the distal end. The two swellings and one of the opesiula- are seen. X 40.
Fig. 7d. The operculum of the same species. X 100.
— 8 a. (Aihcriella licnemunilo (Uusk). X 55.
— 8 1). The same species from the basal surface.
A transvcrselv placed vibraculum is .seen. X 55.
— 9 a. lUiplopoma imprexsum (Moll), with primary
zod'cium. In the margin of the zooecia in- ternal pore-chambers are visible. X 55.
— Ob. The opercuUini of the primary zonccium.
X 140.
— 10 a. Haplopouut bimucronalum (^MoUi, with pri-
mary zo(ccium. X 55.
— 10 b. Operculum of the same species X 14(1
— 10 c. Operculum of the primary zoicciuni of the
same species. X 140.
— 11a. Operculum of I'orelhi (?) cornutd u sp.
X 75.
— 12 a. A developing odciuin of Smilliim Smilli
(Kirchcnp). The development of the crypto- cvst of the distal zou'cium has begun. X 40.
— 13 a. Tnjposlega vcnuslii (Norman). Three small
dwarf-zoa^cia are seen and a larger wliioli surrounds an (xecium. X 40.
— 13 b. The distal end of a zocecium of the same
species. X 75.
— 13 c. .\n operculum of the same species. X 75.
— 13(1. The aperture of a dwarf- zoiccium with
operculum. X 200.
— 14 a. An o(fcium of Sclenulomus (Icniicnhilux
(IJusk;, and its surroundings, seen from the frontal surface. X 40.
— 15 a. A zodcium of Fsrluirella imuicma Flcm.
var. with developing o(ccium The part com- mon to the zooeciuni and the endooivcium (the 1 basal mark«) is seen. X 40.
C. M.H.Le.mnsen :Brt/oxor:i-
n.XKLI.
/. fie>1o/'/u.ytrii retzcuhiiii- llinckx. 2. Hei . i-ri Uri (urn Us Biuvk. 3. Oiuuohocella Sfi- 't. h'leott-a an-^iLla.rcbTv.sp.S. /i. JVurnicini i^.s/i . 6\ JVe.'tlCa. SL^nftloK^iBiisJc.. 7. Tllalcc- ino/iorella c-in-cta^ HiiAlon-. S . Caheriella. hcneimin-itth BiisTc. S). HajiZopmtiA^t /ii-frssa MolL. /(>. ff. corrvwta Bush. ll.Pore/lcL coiviuUi n.-s/t. /2. SmU^A^jia
Icc-
Sinit/i
KircJi cit/i /y. Tryjiosfii^a vein^sia A'orman ■ 14. Srlrt'OrloTtiitS rLs/i - Ucuiatii s- Brisk. JiWaharel/n i m^rn Ar.ra FI (
• -rsen d«t.
I fin. , L> n r.
0. Cordis luK
Plate XXIII.
416
Plate XXIII.
Fig. 1 a. A part nf the Uciinzocccial la^'cr of Kclcpoiti lessclhilii lliiirUs. Tlirec i)f the kcnoZDfrcMa are rmnislud witli avirularia, IVoiii whici'. poivi-liaiiiuls pass i)Ut to tlic surface of tlic Ucno/ou'i-ia. Four of tliesc pore-cliaiiuols arc seen to perforate the lateral walls of the adjacent Ucnozoceeia. The opercular area of the avicularia is furnished with a well-de- veloped crypfocvst. X 56.
— 2 a. Two kcnozoa-cia from Reiepora lata UusU,
seen from the inner concave surface. The inner, in size strongly reduced, very irre- gular cavities of the keiiozoa'cia arc con- nected through pore channels perforating the lateral walls. X 40.
— 2 b. .\ third kenozoiceium of the same species,
seen from the inner surface and in such a position that the stratification of the basal wall can be seen. The inner cavity, whicli is nuieli larger than that in the two other kenozocccia, is |)laccd near to the inner suil'ace and there is seen a numbei' of pore- channels and I'osette-plates corresponding to the ea\ities in tlu" adjoining kenozoo-cia.
X -lu.
— 2 c. The same kenozoceeiujn seen from the left
side-walL Seven single pored rosette-plates are .seen, the five hindcrmost of which cor- respond with the pore-cliamiels seen in the left side of the fignie 2 b. X 40.
— 3 a. A longitudinal section through a bi'anch of
Hctipiira celliilnsa Smilt. On the right side are seen the zocecia, while the rest of the branch is formed by the kenozocecial layers, the youngest of which have covered a S/ti- rorbis. X 12.
— 4 a. Rliynchopora aiujiilala n. sp. X 5.').
— 4 b. A ziKcciuni of the same species, seen from
the left side-wall. On the left side is seen an avicularium. X S.'i.
— 4 c. Zocecia of the same species, seen from the
basal side after removal of the basal wall. X .■).').
l-ig. 4d.
— 4 e.
— 4 f.
— 7 b.
— 7 c.
— 7d.
— / t
— 8 a
— Hb
— 9 a
— 10 a
— 11a
Zonecia of the same species with ixrcia.
X :>.■).
The same species The aperluic with Ihc opei'culum in siln. The beaded \eslibnlar ai'ch is seen shining thi'ough the n|)ercuhnn. X 100.
The same s])ccies. Onecium, seen a little from the proximal part to make the screen- like frontal lobe more distinct. This lobe cannot be seen in fig. 4 d. X 55. Operculum of the same species. X 100. Avieularian mandible of the same species. X 100.
Operculum of Rht/ncliojiora scinlillans (Hincks). X 140.
Two zocccia of Microiiorrlla Ihihclliin'nt n. sp. X 40.
The same species. .A zocecium with iKcciiim. X 40.
Oi)ei'culum of the same s])ecies. X 75. Concscliarellina antfulopora (Ten-Woods). Between the two avicularia is seen one of the peculiar crescentic apertures, belonging to certain kcnozooecia. X 75. The same species. A crescentic aperture and two avicularia. X 75. Opercidum of the .same species. X 100. A transverse section of the same operenlnm. X 200.
The aperture of the same species. X 75. An avieularian mandible of the same spe- cies. X 200.
Conescliarellina ciiiuclliila (linsk). Occeium. X 55.
An on'cium of the same spe«ies, from the .side. X 55.
Adeonello])sis foliacea Mae dill. Four zoie- cia and a gonozoircium, X 40. A part of the frontal surface of AiKirllira- pora inoiwdon IJusk . X 200. A part of the frontal surface of Invcrsiuhi iniHTsii iWalers . X 200.
(/ .// /iZermseii , Bri^ozoa .
nsxm.
-/. Rftc./mrd- fj'ssellatf/- liuKfA-s. 2. Re/ (ul<i Biusk-. 3 fiei- cellu,U)s<i Smi-tt.. i- Nfiyiuv/it/ra an^iZai<i- n. sp ■ J>. /iJujn.c scintillati^v Hineks. ff jWicmpoTcf/a /'/alicKu/eru rt^ s/l 7. Chneschareliina an^iciopoj-a- Ten M^oooLs . S. Bipora, cnn^liiia Bii.s-k .9 yldeoneUopsts foHa.cea. Mac Oill . /O. Anartkropor(v tnc- iu>(ii'n, Husk. II. In^ersiula. inve^sa IVaJers.
■^'eoinscn dcC.
yiHntrii f>rf De6 flbf^t^f^s^eiysk*- Utabl
C.CcnUs ittii:
Plate XXIV
27
418
Plate XXIV.
TiK. 1 a
Concscharellina philippensis (Busk). Kive zod'c-ia are seen from the basal side (after the removal of the frontal wall) showing a number of avicularian ehambers, wliieh arc connected partly with the zo(Ccial sur- face and partly with each other through rosette-plates and pore-channels. There is also seen one of the peculiar kenozotecia, which are provided with a narrow semilu- nate apci-turc. X 75.
Discopora Sarsi (Sinitt) from Tassiusak, Kast-Greenland. The ocecia show a more or less developed txecial cover. X 40. Hippojiodina fieijceitfis (Busk). X 40.
3 b. The same species with avicularia but with- out ooEcia. X 40.
3 c. The same species with another form of avicularia. X 40.
3d. The same species with tlie avicularia in another position. X 40.
3 c. A mandible of the same species. X 75.
3 f. A zooecium with o(ecium of the same spe-
cies, seen from the left side-wall. X 40.
4 a. Cheilopora simcra (Smitt). Two zocecia with
oceeia seen from the left side-wall. X 23.
5 a. Smiltina foliacea (Ellis & Sol.), with ooecia.
2 a
3a
Only a very small proximal part of the ectiHKVcium can be .seen, and the rest is concealed by a tiipartite ocecial cover (sec pag. 04). X"40. Fig. 0—18. In the following diagrainmatie represen- tations of difl'erent hyperstomial odcia the black colour designates the calcareous parts, the red the membranaceous and the non- coloured |)ortion the muscular. The dotted lines arc only hypothetical. Meference letters: av. avieularium. ccto. Ectoo<L'cium. cndo. Kn- oiceium. Cr. Cryptoeyst. c. m. Coveiiug mem- brane o[). Ojierenlum. o. o. Oa'cial opercu- lum, o. c. Oiecial cover, v. \'estil)uluni.
— 0. Flustra nieiiibninaceo-lruncata (Smitt).
— 7. FItisIra /hislroides (Hinck.sl 8. Fliistra foliacea L.
— 9. Cohimnarid borealis n. sp.
— 111. Onjichocclla sp.
— 11. I'rceolipora nana Mac Ciill.
— la. Onchopora Sinclairi (Busk).
— 13. Biujiila sp.
— 14. ThnlamoporeUa sp.
— 15. EmlHillothcca (iiimlrata (Mac fiill.). 16. Cdllo/jora iiurila (Hincks).
— 17. Scliizoporella unicornis Johnst).
— 18. Myriozoian coarctalum Sars).
G. M R.Lvinn.Vfn , Btyozoa -■-cni
PLXK'IV^
-/. ConesrJuiTcUi7ia, ;i/ulfi/i/iensts Busk 2. Discnporn SursC Smttt J. //i/i/m/ioiiinn. fec/jteiL- Sis Bttg/r . 4. Chfrilo/iorci smccra Siii Ht S. Sinittin/i, yhlinoea^ I^JU.is <^ Sol. S. Plustra. inetn.- br<tn(tri;0'trun rata- Snii.it 7 M./lu.vtroidis J^incks. S. FL Joliucetx. X . J>. Coliuit.naruL borc-
nlis fus/L. /O. Oni^choceUa. sp.. // L/rc^nii/iora na-iua Max> G^i-W. 12. CalwalUa. Sin.cLa.iri. Busk, 't.^ Butjulxi. U/. T/uuLamojix>re:lUt- 15. Jiinbcdlotke.ca. ^vcuJjcvta, Alfic. a,LL. 16 Callojivrn, aiirCUt. ffinrks -// Srhizo/iorelia, uni.coniA.s Juhnsl. 18. Myriuzowni, cocurctafunx. Sars
IjCt'inseti dal..
„^;.t.%j h,. n«t. ACiea».^j-«^l^ z^a^a/
INDEX.
abyssicola (Escharella), 315.
abyssicola (Sarsiilustra), p. 124.
Acanthostcga, p. 12.
acarocnsis (Smittina), p. 342.
aculeata (Farciniinaria), p. 118.
acutirostris (Porclla), p. 336.
Adcona, p. 283.
Adconella, p. 283.
Adeonellopsis, p. 283.
Adconidac, p. 282.
advena {Discoponi), p. 348.
Aegon (Aspidostoma), ]). 173.
Aetea, p. 92.
Aeteidae, p. 92.
Agassizi (Membraniporella), |). 17.
akarocnsis (Smittina), p. 342.
alata (I'tcrocclla), p. 246.
albispina (Chaperia), p. 115.
albicans (nol()|)orclla), ]). 348.
Alderi (Escharina), p. 32G.
Alderi (Bicellarina), p. 99.
Alderina, p. 150.
Alysidiidac, p. 201.
Alysidiuni, p. 202.
Amphibleslrum, p. 150.
amplcctcns (Klcctra), p. 66, 146, 147.
Anarthr()]){)ra, p. 5, 314, 317.
Anasca, p. 12, 91.
anguina (Aetea), ]). 92, 93.
angulata (KIcctra), p. 149, 156, 160.
angulatuiii (Hiiynchozoon), ]). 291, 294.
angulopora (Concscharellina), 311. annulata (Cribrilina), p. 159. annularis (Hijjpothoa), p. 277. annulus (Chaperia), p. 115. Antiopa (Aspidostoma), p. 173. aperta (Holo])orella), p. .348. apiculata (Holoporella), p. 348. aporosa (Hippothoa cornuta, van), p. 279. appendiculata (Nellia), p. 119. arac'linoides (Canda), p. 131, 142. Arachnopusia, p. 160. arctica (Smittina), p. 340. armata (Hoplitella), p. 122, 136. armata (Cribril. philomela, var.), p. 160. armata (Schizoporclhi). |). 294. Arthro])oma, p. 314, 332 . A.sc-ophora, p. 12, 213. Aspidelectra, p. 160. Aspidostoma, ]). 170. Aspidostomidae, p. 170. Atalantlia (Aspidostoma), p. 170. atlantica (Farciniinaria), p. 119. auriculata (MaNwellia), p. 296, 300, 340. aiirita (Callopora), p. 150, 151. aurita (Claviporella), p. 243. australiensis (Haswellia), p. 296, 297, 300. avicularis (Cellcpora), p. 346. aviculifera (Petralia), .350, 351.
Beania, p. 97, 110.
Beaniana (Retepora), p. 291.
27*
420
bcllula (Elcctra), p. 146.
bcncc-oslala (Costicella), ]). 237.
l)oiuMminita (Calu'riclla), p. 135.
liiapi'iln (Schizoporella), p. 323.
Bicellaria, p. 99.
Biccllariidac, p. 93.
l)ii-irrhala (lioloporella), p. 348.
bicolor (Klcctra), p. 147.
bii'ornis (Calwollia), p. ICrl.
bicornis (PctalosU-gus), p. 114, 157.
bicuspis (Petralia), 350, 351.
Bifaxaria, ]). 302, 304.
Bif lustra, p. 144.
bilabiata (Eurystomclla), p. 36, 314.
bilaniinala (Disco])ora), p. 313, 344.
l)iimiir()naUini (Ha])l(ip<)iiia), p. 280.
biiminita (Schizojiort'lla), j). 287.
Bipora, p. 311, 312.
biseriata (Kcnclla), p. 123, 121.
biscrialis {nSchizoporcllm), p. 10.
bisiniiala (Petralia), 350, 351.
bispinosuni (Rhynchozoon), |). 201.
biturrila (Scliizoponila), |i. 301.
bombycina (Oiu-lioporella), p. 26,'i.
borcalis (Coliiinnaria), p. 116.
borealis (Siiiitlina), p. 340.
borcalis (Tessaradoma), p. 304.
Boryi (Sinio])C'lta), p. 347.
Braccliridgia, p. 283, 289.
Bretlia, p. 98, 113.
brevispina (Electra aniplccli'iis, var.), p. 147.
I?ronnniarti (Cliori/opora), p. 275.
tiruniica (Hoioporclla), ]). 348.
Bugula, p. 96, 100.
Bii->iilaria, p. 99, 108.
ButJulDjjsis, p. 135.
Buski (Steganoporclla), ]). 168.
Buski (Menipca), p. 132.
Caberea, p. 134.
Cabcriclla, p. 134, 135.
(>alcscliara, ]). 152.
caliciita (Bugula), p. 100, 101.
californica (Thalatnop. Hozicri, var.), p. 184.
Callopora, p. 79, 1 50.
C.aUyinmophora, p. 269. Caloporclla, p. 251. Cal|)('iisia, p. 165. Calpidiuui, ]). 221, 249. Calwellia, ]). 259. Cainarrtstega, ]>. 12. cancellala ((^oncscharcllina), j). 310. Canda, p. 134, 141. capcnsis (Cliaperia), p. 39, 115. capulus (Lunularia), j). 155. caraibica (Bugula), p. 101. caraibica (Canda), p. 1 12. Carhasea, p. 69, 128. carbasea (Flustra), p. 124. carinata (Ptcrocclla), p. 248. caslanea (Petralia), p. 350, 351. Catenaria, p. 221, 253. Catcnariidac, p. 213. Calenicella, p. 213, 221. (Mtcniccllidac, p. 213. Catcnicellopsis, p. 245. catenularia (Electra), |). 116. C.ecili (Arthropoiiia), p. 332. Cellaria, p. 209. Cellariidae, p. 209. Collarinella, p. 304. Ccllcporclla, p. 346, 347. Cellepora, 345, 346, 347, 348, 349. Cclleporidae, p. 345. CcUularia, p. 209. Ccllulariidae, p. 209. eellulosa (Helepora), ]). 294. centralis (Macropora), p. 163. cereoides (Tubucellaria), p. 306. cervicornis (Cha])cria), j). 115. cervicornis (Menipea), ]>. 132. Challengeria (Schizoporella), p. 314. r.baperia, p. 38, .39, 97, 115, .3.50. (Hieilopora, p. 353. cheilostoma (Smittina), p. 340. Cheilostomata, p. 88, 91. Clilidonia, |). 197. Clilidoniidae, p. 196. c-litliridiata (Figulina), p. 160. 26.5. (".liori/opora, p. 275, 276.
421
ciliata (Bicellaria), p. 53. ciliata (Microporella), p. 328, 329. cincta (Tlialamoporell;i), p. 179, 192. cinctipora (Schizoporelhi), p. (i. circinata (Arthropoma), p. 332. circumcincla (Hippoporina), p. 353. cirrata (Maplestoiiia), p. 113. Clarkei (Macropora), p. 162. clathratiis (Pleurotoicluis), 36, 270. claviciilata (Lepralia), p. 281. Claviporclla, p. 10, 220, 242. clausa (Mcnipea), p. 38. coarctatum (Myrlozoum), p. 301. coccinea (Escharoides), p. 318. Coilostega, p. 12, 16, 161. collaris (Sinittina), p. 340. Columnaria, p. 116. compacla (Mcnipea), p. 132. compacta (Orthopora), p. 311. compres.sa (Porella), p. 2, 336. concinna (Porella), p. 1, 336. concinna ())Schizoporella«), p. 6. Conescharellina, p. ,309, 310, 311. Conescharellinidae, p. 308. contorta (Escharoides), p. 318. contracta (Systenopora), p. 304. C.ordicri (Chlidonia), p. 197. coriacea (Micropora), p. 162. Cornucopina, p. 98, 109. cornuta (Catenaria), p. 256. cornuta (Hippothoa), p. 278. cornuta (Porella?), p. 10, 338. coronata (llaswellia), p. 299. corrugata (Bifaxaria), p. 304. costata (Disiopora), p. 343. costata (Siniopelta), p. 347. Costazzi (Siniopelta), p. 347. Costicella, p. 10, 220, 233. Cothurnicella, p. 197. (Uaspedozoum, p. 73. crassa (Fliistra), p. 122. crassatina (Monoporella), p. 16.3. Crateropora, p. 170. eraticula (Callopora), p. l.")0, 151. crenulata (Labiopora), p. 174.
creniilatum (Rliyncliozoon), p. 294.
Crepidacantha, p. 266.
Crepidacanthidae, p. 266.
cribraria (Cribricella), p. 240.
Cribricella, p. 220, 238.
cribriformis (Relillustra), 12,3, 128.
(]ribrilina, p. 158.
Cribrilinidae, p. 1,56, 157.
crinispina (Crepidacantha Poissoni, van), p.
266. cristata (Chaperia), p. 38, 39, 1 1 5. cnistaceum (Myriozoiim), p. 297. crystallina (Menipea), p. 132. cryi)toeciuni (Cribrilina), p. 159. ciicullana (Smittina trispinosa, van), p. 341. Cupularia, p. 154. cuspidata (Biigulopsis), p. 132. cuspidata (Costicella), p. 235. cyathus (Menipea), p. 133. Cyclicopora, p. 314. 335. Cyclicoporidae, p. 335. cylindracea (Chaperia), p. 115.
danica (Menibranipora), p. 144. Darwini (Caberea), p. 37. dacdala (Cothurnicella), p. 197. daedala {nScIiizoporellau), p. 326. decorata (Microporella), p. 329. delicatissima (Siijhonoporella), p. 169. delicatula (Menibranipora), p. 144. Dendrobeania, p. 99, 113. dentata (Bugula), ]>. 100. dentata (Onchopora), p. 261. denticulata (Caleschara), p. 152. denticulata (Membranipora), p. 144. denticulata (Spiralaria), p. 1, 125, 126. denticulatus (Sclerodomu.s), p. 302. dentigera (Spiralaria), p. 125, 126. Descostilsi (Holoporella), p. 348. Diachoris, 97, 110. diaphana (Escharella), p. 315, 316. diaphana (Halysisi.s), p. 274. Diazeuxia, p. 276. Diazeiixidae, p. 274. Didymia, p. 98.
422
ililatata (Aetea), p. 92.
Dinictopia, p. 98.
I)iiiiorpliozi)oimi, p. 90, 107,
l)i|)l()(k'rniala, p. 7, 8.
Diploponi (cincta), p. 122.
Diporiita, p. 328.
Discopora, p. 343.
dissimilis (Buf,'ularia), p. 199, 122.
lii.slans (Diathoris niat^ellanica, var.), p. 13.
Disleginopora, p. 21.
dislorta (Elcctra), p. 14(1.
Dilaxipora, p. 259.
(livisa (Sfhizothcca), p. 294.
(iorsiporosa (Pctralia), p. 350, 351.
Doryporclla, p. 150.
(lul)ia (Mcmbranicellaria), |). 207.
Dumcrili ((;all()|)ora), p. 150, 151, 158.
Diitertrci (Escliarina), p. 326.
eburnca (Geiiiollipora), p. 313. Electra, p. 140. elc^ans (Catcnaria), p. 2.55. elegans (I'labellipora), p. 312. elegans (Rhagaso.stonia), p. 150. Rlc'idac, |). 140. EUeri (I'etralia), p. 350, 351. elliptica (Eoveolaria), p. 152. Elli.si (Caberca), ]). 131. clongata (Helepora), p. 291. Emballotheca, p. 01, 333. cnuKTonala (I'lscliai-olla), p. .315. EpUuulidiidw, p. 313. episcopalis (Euthyroides), p. 205. Epistomia, p. 98. errata (Schiz()])orilhi), p. 323. Escbarella, p. 315. Escharellidae, p. 314, 335. Escbarina, p. 314, 326, 328. Escharoides, p. 314, 317, Eucralca, p. 98. Eucratiidae, p. 93. Eurystonu'lla, p. 314. Eiiry.slonicllidae, p. 314. Eulhyris, p. 269. Eulbyridac, p. 269.
Euthyroides, p. 264.
Euthyididau, p. 204.
Exoi-hi'lla, ]). 67, 314, 320.
expansa (Tbalainoporclla), j). 179, 190.
I'alcata (Crateropora), |). 173.
falcifera (Thalamoporolla), p. 179, 186.
Farcimia, p. 119.
Farciminaria, p. 117.
Farciniinariidac, p. 116.
fccgccnsis (Ilippopodina), 1, 353.
ferox (Hianlopora), p. 112.
Fmcslrulina, p. 328, 329.
Iigiilari-s (Figulina), p. 100.
Figulina, p. 159, 265.
lissa (Scbizotbeca), p. 294.
fissurata (Sciititolla iiiargaritacca, var.), p. 231.
Flabellaris, p. 133.
llabc'llaris (MicTojjorclla), ]). 330.
Ilabcllaris (Flabcllipora), p. 312.
flabclligera (Microporclla), p. 328, 331.
Flabcllipora, p. 312.
llabellum (Mcnipca), p. 135.
Flemingi (Callopora), p. 150, 151, 151,
riorea (Spiralaria), ]). 125.
Flustra, p. 124.
Flustramorpha, p. 73, 329.
Fluslridac, p. 122.
Ihislroidcs (Spiralaria), p. 120.
foliacca (Flustra), ]). 5, 6, 2('), 58, 123, 124.
foliacea (.Vdi'oncllopsis), |). 287.
foliacca (Sniittina), p. .340.
Foraniinclla, p. 105.
I'oraiiiinigcra (Eurystomclia), ]>. 31 1.
ronnosa (Catcnaria), |). 254.
fossaria (Electra), |). 1 KJ.
Eoveolaria, p. 152.
frigida (Jirettia), p. 113.
i'rigida (Scuticclla), p. 215.
furcata (Hnd)allothcca), ]). 333.
galeata (Chaperia), p. 38, 115. gallica (Stoniat()])ora), p. 93. Gattyac (Pucllina), p. 159. Gemcllaria, p. 98.
423
(icnu'lli|)(>r;i, p. ;il3.
gt'iiiin;it;i (Chiviiiori'llii), |). 242.
Gephyrophora, p. 29(i, 297, 300.
Gephy rotes, p. 158.
gigas (nLepraUiui), p. 6.
gigantcum (Aspidostoiiia), p. 171.
glabra (Bugula), p. 103.
glaciata (Forclla), p. 3.30.
gothica (Homiscptc'lla), p. 1(54.
gothica (Thalamoporella Rozieri, var), p. ISl.
gracilis (HaswcUia), p. 299.
graniilata (Thalamoporella), p. 179, 188.
granimi (Siniopclta), p. 347.
Grimakli (Chciloijoraj, p. 353.
Grimakli (Onchopora), p. 261.
Haddoni (Steganoporella), p. 168.
Haddoni (Slirparia), p. 103.
Halophila, p. 97.
Haplopoma, p. 276, 279.
Harmeri (Thalamoporella), p. 179, 186.
Harveyi (Strophipora), p. 258.
hastata (Costicclla), p. 236.
Haswellia, p. 296, 297.
Hemiseptclla, p. 164.
Hetcroa'ciiim, p. 146.
Heteroflustra, p. 125.
Hiantopora, p. 97, 110.
Hiantoporidae, p. 113.
Hincksina, p. 125.
Hincksiella, p. 221, 241.
Hippopoilina, p. 353.
Hippo|)odinidae, p. 353.
Ilipimpoiina, p. 353.
Ilippothoa,, p. 2, 276.
Hippothoidae, p. 274.
hirsuta (Tubucellaria), p. .306.
holostoma (llippolhoa cornuta, var.), |). 278.
Holoporclla, p. 349.
Holoporellidac, p. 347, 348, 349.
honolulcnsis flloloporella), p. 318.
honolulense (Myriozoum), p. 301.
Iloplitella, p. 1.35, 136.
hyalina (Hippolhoa), p. 66.
hyalina (Megapora), ]). 151, 269.
Hyndmanni (Kscharina), p. 32(), .327. hystrix (Lekythopora), p. 313.
Ichthyaria, p. 260. imbellis (Callopora), p. 1.50, 151. immersa (Escharellaj, p. 315. immersum (Myriozoum), p. 31 1. impressum (Haplopoma), |). 280. impressa (Galpensia), p. 1()5. inllata (Porella), p. 336. innominata (Piiellina), p. 159. inornata (Lepralia), p. 281. inskliosa (Adeonella), |). 283. invcrsa (Inversiula), p. 317. Inversiula, p. 26, 316.
Jacksoni (Escharoldcs), p. 318. Jacksoniensis (lloloporellai, |). 348. Jacobensis (Smitlina), p. 340. japonica (Petralia), p. 350, 351, 352. .leflreysi (Menipea) , p. ,38. Jeffreysi (Smittina), p. 340. Jellyae (Adeonella), p. 286. Jellyae (Euthyroides), p. 264. Jervoisi (Thalamoporella), p. 179, 193.
Kenella, p. 124. Kinetoskias, p. 99.
labiata (Escharoides), p. 318.
labiata (Hemiseptella), p. 164, 1(55.
labiata (Porina corona la, var.), p. 297.
labiata (Thalamoporella Rozieri, var.), [). 182.
Labiopora, p. 170.
labrosa (Porina coronata, var.), p. 297.
Lacroixi (Membranipora), p. 1 1 1.
Lafonti (Savignyella), p. 274.
Lagenipora, p. 347.
Lansborovi (Smittina), p. 1, 340.
laqucata (Escharella), p. 315.
larvalis (Escharoides), p. 318.
lata (Retepora), p. 11, 292.
lateralis (Steganoporella), p. 168, KiO.
Lekythopora, p. 313.
Lekythoporidae, p. 313.
424
Icpida (ForamincUa), p. 165. lepralioidcs (CcUvporella), \^. 347. liyulata (MenipiM), p. 140. limosa (Membranipora), p. 145. linearis (Sinittiiia), p. 2, 28, 340. lincata (Oaliojjora), p. 150, 151. Liriozoa, p. 313. I.iriozoidae, p. 313.
lioticlia (Tlialamoporella), j). 178, 179. lobata (Exochclla), p. 321. longipora (Cyiiicopora), p. 3,35. loiif^irostrc (Rhynchozoon), p. 294. longirostris (Exochclla), p. 321. longirostris (Schizoporella), p. 323. l<)ngis|)inata (Escliarina), p. 326. Lowei (Cupularia), p. 155. Liiciac (Onychocella), p. 153. lucida {»Schizoporella((), p. 294. lucida (Siniopclta), p. 347. Lunularia, p. 155. Lunulariidae, p. 155. Lumililes, p. 1.55. laevis (Porclla), p. 336.
Macropora, p. 162.
niacnlala (Sculicclla), p. 228.
magellanica (Diachoris), p. 13.
magnifica (Pctralia), p. ,350. .331.
magnilica (Steganoporclla, neozclanica, var.),
p. 1()8, 169. inagnilabris (Slcganoporella), p. 168. iiiagnirostris (Tiibiporella), p. 307. niajiisfula (Smittina), p. 340. Malacostcga, p. 12, 16. 91. malleolus (Siuillina), p. 340. Malusi (Microporella), p. 328, 320. mamillaris (Thalamoporclla), p. 179, 194. Mapleslonia, p. 113. margaritacca (Seutieella), p. 228. margarilifera (Porella), p. 336, 337. marginala (Miero|)orclla), p. .328, 329. marionense (Myriozoiim), p. 301. marsui)iiiiii (Porella), p. 336. marsupiala (Scrupocellaria), p. 38. Martiali (Escharoidcs), p. 318.
Masligophora, p. .326. Megapora, p. 151, 208. nicditcrranca (Retepora), p. 293. nielolontha (Aspidclectra), p. 160. niembranacca (Membranipora), p. 17, 144. mciiibranaceo-lruiu-ata (Flu.stra), p. 54, 58,
123. Mcmbranicellaria, |). 207. Mcmbraniccllariidac, p. 158, 207. Membranipora, p. 144. Membraniporella, p. 79, 158. Mcmbrani])oridae, p. 143. membranipoiides {Ftiistra), p. 1,38. Membraniporina, p. 145. Menipea, p. 135.
Michaelseni (Hemiseptclla), p. 104, 165. Micropora, p. 162. Microporella, p. 280, 283, 315, 328. Microporellidac, p. 283. Microporidae, p. 162. microstoma (Escharella), p. 315. Microstomaria, p. 2.59. minax (Callopora), p. 150, 151. miniita (Porella), p. 336. monoceros (Arachnopusi.a), p. 113, 160. Monodermata, p. 7, 8. monodon (Anarthropora), p. 2, 6, 317. Monoporella, p. 165, 349. nionostachys (Electra), p. 28, 146, 1,56. Moseleyi (Carbasea), p. 75. Mucronella, p. 315. mullispinata (Escharella), p. 315. Murrayana (Dendrobeania), p. 113. Myriozoella, p. 297. Myriozoidae, p. 296. myriozoides (Reteporella), |). 303. Myriozoum, p. 297.
nana (Urceolipora), p. 75, 270.
Nellia, p. 119.
neozclanica (.Slcganoporella), p. 168, 169.
neritina (Biigula), j). 50.
Nichtina, p. 144.
nitida (Membraniporella), p. 158.
nitido-punctata (Cribrilina), p. 1,59.
425
nobile (Dimorphozoiim), p. 107.
nobllis (Flustra), p. 107.
nodosa (Siphonoporella), p. 170.
nocUilifera (Monoporella), p. 165.
Normani (Micropora), p. 162.
Notamiidae, p. 93.
novae hollandiae (Thalamoporellal, p. 179, 186.
novae zelandiae (Rotepora), p. 291.
nutrix (Inversiula), p. 317.
oblonga (Membranipora), p. 144. obtecta (Euthyris), p. 272. occlusa {»Escharoides<(), p. 301. octodon (Flustra), p. 126. oculata (Ncllial, p. 129. Onchopora, p. 260. Onchoporella, p. 260. Onchoporidac, p. 259. •
Onchoporoides, p. 260. Onychocella, p. 1, 11, 153. Onychocellidae, p. 153. Oochilina, p. 143.
opuntioides (Tiibiicellaria), 305, 307. ornatum (Calpidium), p. 251. Orlhopora, p. 314. Oslliimosia, p. 347. Otto-Muelleriana (Smittina), p. 340. ovata (Discopora), p. 343, 344.
Pallasiana (Smittina), p. 6, 340.
palmata (Smittina, = solida), p. 2, 340.
parasiticum (Alysidium), p. 202.
patagonica (Menipca), p. 133.
patula (Steganoporella), p. 174.
l)atiilosa (Chaperia), p. 115.
pavonella (Discopora), p. 2, 17, 18, 32, 33, 343,
344. Peachi (Bugulopsis), p. 132. Peaclii {MiicronelUi), p. 315. Perislomclla, p. 317. perforata (Micropora), p. 162. pes anseris (Escharina), p. 326. Petalostegus, p. 97. Petralia, p. 350.
Petraliidae, p. 350.
pliilomela (Figulina), p. 159.
phillipensis (Concscharellina), p. .309, 310.
picoensis (Onchopora), p. 261.
pilosa (Electra), p. 28, 70, 146.
pisciformis (Flustra), p. 25.
plagiostoma (Scuticella), p. 222.
plana (Porella), p. ;5.'56.
platalea (Siniopelta), p. 347.
Pleurotoichus, p. 270.
plicata (Discopora), p. 344.
Porella, p. 336.
Poissoni (Crepidacantha), p. 10, 71, 266.
polita (Escharclla), p. 315.
polymorpha (Gephyrophora), p. 29(), 300,301.
polymorpha (Holoporella), p. 348.
ponderosum (Calpidium), p. 249.
porifera (Smittina), p. 340.
Porina, p. 297, 304.
porosa (Petralia), p. .3,50, 351.
praelonga (Cyclicopora), p. ,335.
praelonga (Cheilopora), p. 353.
praelucida (Cheilopora), o. 353.
pracstans (Escharoides), p. 318.
princeps (Porella), p. 336.
proboscidea (Porina), p. 304.
profundum (Rhynchozoon), p. 291, 294.
projecia (Lepralia Pallassiana, var.), j). 340.
prominens (Thalamoporella Rozieri, var.), p.
188. propinqua (Smittina), p. 340. Pseudoflustra, p. 339. Pseudostega, p. 207. Pterocella, p. 220, 242. Pucllina, p. 159. pulchella (Hincksiclla), p. 241. pumicosa (Cellepora), p. 345. punctata (Cribrilina), p. 159. pusilla (Claviporclla), p. 245. Pustulipora, p. .303. pj'gmaea (Adeonella), p. 287. pygmaea (Celleporella), p. 34{i. pyriformis (Bracebridgia), p. 289. Pyripora, p. 146. pyrula (Membranlporina), p. 157, 160.
426
(|u:ulr:ita (Rniballolhcca), p. 333, 334.
(liuiilridrnlaUi (liwiiild), p. 113.
r:uii:it;i (PuclliiKi), p. LW. radiriiVra (Ilianlopora), p. HI. rannilosa (Cellopora). i). ;U('), :U9. roi-lilincata ll'elralia), p. 3.')(), 3,31. lU'lcpora, p. 291. Holcpdridae, p. 290. reliciiliiiii (Hi'tilUisIra), p. 12(). rc'licuhita (Smillina), p. 3 JO. R'tic'iilalti-punctala (Siiiitlina), p. 340. relironuis (Cauda), p. 142. Rhabdo/.Dum, p. 133. Rluimiilutnotiis, p. I.'jO. niuimphoslomclla, p. IS. .33, 343, 344. Hhynchozoon, p. 294, 29."). rinjiiMis (Mef-apora), p. 151, 209. lobiirala {Mciiipca , p. 138. Romancheina, p. 317. Rosscli (Calcschara), p. l.">2. liosscUaiia, p. l.')2. rota (Siniopclta), p. .347. Rozicri (Thalamoporclla), p. 178, 181. rudis (Siniopclta), p. 347, 349. nila (Cribricella), p. 239. nislit-a (Pustulipora), p. 303.
saccata (Forclla), |). 336.
sacfulata (ScuticolhO, j). 233.
Salicornaria, p. 209.
Salicornariadde, p. 209.
sangiiinca (Schizoporclla), [). 323.
.Sarsi (Discopora), p. 343, 314.
.Sarsinustra, p. 124.
saiirof^lossa il-'scliaroidcs , ]>. :U8, 319.
Savarti (Mc'mi)rani])ora), p. 1, 144.
Savignyella, p. 274.
Savif^nyellidac, p. 273.
scabra (Discopora), p. 343, 344.
scabra (Scrupoccllaria), p. (iO, 347.
Schismopora, p. 347.
Scbizoporclla, p. 315, 322, 333.
Schizothcca, 294.
Schonaui (Hclillustra), p. 127.
scinlillans (l{h> ncbozooii), p. 294, 29(>.
Sclcrodoiiiidae, p. 301.
Sclerodomus, p. 302.
Scrupoccllaria, |). 134.
Scrupoccllaridac, p. 130.
Scuticella, p. 215, 220, 221.
sccurifrons (Fhislra), p. 1, 5, (i, ,")7, 58, 123.
Sclenaria, p. 155.
scrrata (.\deoiiclIa), p. 284.
scrrata (Spiralaria), p. 12fi.
sorraliroslris (Holoporclla), p. 318.
scrrulata (Flustra), ]). 1, 2, 5, 122.
Scto.sella, p. 190.
Setosellidae, p. 196.
simplex (Canda), p. 142.
simplex (Escharina), p. 326.
simplex {Maplcstoiiia\ p. 113.
simplex (Myriozoum), |). 3(il.
simplex (Nellia), p. 121.
sincera (Chcilopora), p. 353.
Sinclair! (Onchopora), p. 260.
Siniopclta, p. 347.
sinuosa (Retepora), p. 291.
Siphonoporella, p. 108.
Skenei (PorelhV, p. 336.
Smittina, p. 339, 343, 344.
Sniittinidac, p. 335.
Smitti (Smittina), p. 340.
socialis (Layenipora), 345, 346.
solida (Costicella), p. 235.
solida (Onycbocclla), g. 1.53.
solida (Pseudoflustra), p. 340.
Sophiac (Tegclla), p. 1.52.
sparsipunctata(Thalamop. Rozicri, var.), p. 183.
spathulifcra (Callopora), p. 45, 71, 150, 151.
spicala (Mcnipca), ]). 132.
spinifcra (Escliarina), p. 32(), 328.
spinigera (Discopora), p. 343.
spinosa (Chapcria), p. 39.
spinosissima (l-:scharclla), p. 315.
spinuligcra (Spiralaria), p. 125, 126.
Si)iralaria, p. 125.
spongites (Scbizoporclla), ]). 323, 324.
stapifera (Thalamop. graniilata, var.), p. 188.
Stl] /i)/i<rvr ty- ^'
427
Steganoporella, p. 37.
Stcganoporellidae, p. 167.
steganoporoitics (Hemiscptclla), ]>. 164, 165.
Steginopora, p. 21.
stellata (Turriligcra), p. 313.
stenostoma (Est4iarclla), p. 315.
Stenostomaria, p. 259.
Stirparia, p. 103.
Stolonella, p. 97.
Strophipora, p. 257.
striunata (Lepralia Pallasiana, var.), p. 340.
struma (Porella), p. 336.
subgracile (Myriozouni), p. .301.
subimmersa (nLc/jniliad), p. 6.
Systcnopora, p. ,304.
Tata, p. 18. . ^0 Tegella, p. 152. Tendra, p. 146. tenella (Xellia), p. 120. tenuicosta (Menibraniporella), p. 265. tenuis (Canda), p. 142. terminata (Cribrilina), p. 160. Tessaradoma, p. 304. tesselata (Retepora), p. 292, 293. Thalamoporella, p. 178. Thalamoporellidac, p. 175. Thenardi (Petralia), p. 350, 351. transversa (Holoporclla), p. 348. transversa (Membranipora), p. 192. triacantha (Electra), p. 146. triacantha (Holoporclla), p. 348. triangula (Smittina), p. 340. tricuspis (Exochella), p. 320. tridcnticulata (Holoporclla), p. 348. trifolium (Callopora), p. 150, 151. triseriata (Mcnipea), p. 1.32. trispinosa (Smittina', p. 1, 2, 5, 340. tropica (Chaperia), p. 115. truncata (Aetca), p. 92. truncatum (Myriozoum), p. 301.
Trypostega, p. 280. tubcrculata (Membranipora), p. 144. tuberculata (Holoporclla), p. 348. tuberosa (Petralia), p. 350, 351. tubifcra (Thalaniop. graniilata, var.), Tubifera, p. 166. Tubiporella, p. 305. Tubucellaria, p. 305. Tubuccllariidae, p. 304. tubulifera (Porella), [). 336. tiibulosa {»Miicronetla«), p. 291.
Umhomila, p. 343, .341. iincinata (Farciminaria), p. 117. undata (Petralia), p. 350, 351. unicornis (Schizoporella), p. 323. unicornis (Tegella), p. 1.52. unispinosa (Smittina), p. 310. Urceolipora, p. 269. urnula (Scuticella), p. 231.
variolosa (Escharella), p. 315. vcntricosa (Escharella), p. 315. vcnlricosa (Scuticella), p. 227. venusta (Trypostega), p. 281. verrucosa (Holoporclla), p. 348. verrucosa (Discopora), p. 343. verticillata (Electra), p. 146. Vincularia, p. 164. violacea (Adeona), p. 283. Viltaticella, p. 221, 2.53. vulgaris (Escharina), p. ,326, 327. vultur (Petralia), p. 350, 351.
p. 187.
/eji/ztfL'^c f.-'cA, !>! Si
Wallichiana (Retepora), p. 291. Watersi (Lekythopora), p. 347. Watersia, p. 91, 95, 99. Wilsoni (Rhabdozoum\ p. 142.
zdanica i Exochella', p. .322. zostcricola ^Electra), p. (Hi, 146.
ERRATA AND REMARKS.
|
2 line |
3 |
from |
below |
»lrreguliers« |
sboiild |
be |
■ in-ef^ulier. |
|
5 — |
6 |
— |
above |
»0t(( |
— |
- |
to. |
|
5 - |
16 |
— |
— |
»calk(( |
— |
- |
chalk. |
|
6 - |
8 |
— |
— |
^Scliizopnrclla"- |
— |
- |
nSchizoporellau. |
|
8 - |
3 |
— |
— |
»Cihriliiui« |
— |
- |
Cribrilina. |
|
12 - |
8 |
— |
— |
nCoilcslec/ciK |
— |
- |
Coilostega. |
|
18 - |
3 |
— |
below |
»Smilliau |
— |
- |
Smiltina. |
|
19 foot-note No |
. 9 |
18 |
— |
- |
19. |
||
|
26 |
— |
- |
1 |
79, p. 42 |
— |
- |
80, p. 421. |
|
34 |
- |
- |
2 |
81—83 |
— |
- |
460, 462. |
|
36 |
— |
- |
2 |
23 |
— |
- |
49. |
|
38 |
- |
- |
2 |
80 |
— |
- |
81. |
|
42 |
- |
- |
2 |
75, PI. Ill, fig. 16 |
— |
- |
76, PI. Ill, fig. 16 a |
|
44 |
- |
- |
5 |
72 |
— |
- |
76. |
|
48 line |
12 |
I'roni |
Ijclow |
»laminae« |
— |
- |
lamina. |
|
76 fool |
-not |
e No |
. 1 |
108 a |
— |
- |
108 b. |
|
82 line |
7 |
from |
al)ove |
Lepralia : |
— |
Lepralia. |
|
|
84 |
6 |
- |
below |
nRhynchoporm |
- |
Rhynchozoon. |
|
|
89 - |
7 |
— |
— |
nAspidaslomidac n. |
f<( - |
- |
AspidosloniUiac. |
|
103 - |
7 |
— |
— |
))V()1. X(( |
Vol. X, Part. 1. |
||
|
107 - |
16 |
— |
above |
- ))Sec.<( |
— |
- |
Soc. |
|
109 - |
5 |
— |
— |
56 |
— |
- |
55. |
|
HI foot-note No, |
. 2 |
22 |
— |
- |
208. |
||
|
112 |
— |
- |
1 |
22 |
— |
- |
208. |
|
114 line |
16 |
from |
above |
XXXI, I |
— |
- |
XXXI, III. |
|
118 - |
4 |
— |
below |
"preceedin^H |
- |
preceding. |
|
|
122 - |
3 |
— |
— |
))mee« |
— |
me. |
|
|
124 - |
12 |
— |
above |
»operciiliim<( |
— |
- |
mandible. |
|
129 ~ |
6 |
— |
below |
»no« |
- |
- |
not. |
|
133 |
18 |
— |
above |
))joint« |
— |
- |
internode. |
|
140 - |
12 |
— |
— |
))opening« |
— |
- |
aperture. |
430
|
117 |
line |
11 |
from |
below |
195 |
should be 332. |
|||
|
152 |
fool |
-note No. |
1 |
))Vol. 2 . . . lig. |
8« |
— |
- |
Vol. 1 .. . figs. 8a-8d. |
|
|
153 |
- |
- |
- |
2 |
84 1) |
— |
- |
84 e. |
|
|
153 |
- |
1 |
7 |
— |
- |
271. |
|||
|
168 line |
7 |
from |
nbovc |
)iol)servations« |
— |
- |
remarks. |
||
|
171 |
— |
16 |
— |
below |
»Part I, Cheilostomalaa |
— |
- |
Cheilostomala. |
|
|
171 |
— |
12 |
— |
— |
))Vol. V<i |
— |
- |
Vol. X. |
|
|
173 fool-note No. |
1 |
11 a |
— |
- |
lie. |
||||
|
179 line |
9 |
from |
nhove |
Mzooccialw |
— |
- |
zooecial aperture. |
||
|
180 |
— |
1 |
— |
))\vell— devclo]) |
eild |
- |
- |
well-developed. |
|
|
181 |
— |
16 |
— |
— |
28 |
— |
- |
379. |
|
|
181 |
— |
17 |
— |
»l';irl Ic< |
— |
- |
(Ihciloslonuitii. |
||
|
185 |
— |
11 |
-- |
11 |
— |
- |
40. |
||
|
186 |
10 |
28 29 |
— |
- |
380. |
||||
|
192 |
- |
7 |
- |
21 |
— |
- |
89. |
||
|
193 |
— |
IS |
30 |
— |
- |
381. |
|||
|
194 |
- |
IS |
)inee« |
— |
- |
nee. |
|||
|
197 |
— |
s |
— |
»Egypte« |
— |
- |
Kgypte. |
||
|
197 |
- |
10 |
- |
— |
1859 |
— |
- |
1858. |
|
|
207 |
— |
1 |
^- |
— |
».Subclivision<( |
— |
- |
Division. |
|
|
212 |
— |
19 |
— |
below |
BJoint" |
- |
- |
internode. |
|
|
215 |
- |
17 |
— |
above |
»articulale par |
ts« |
— |
internodes or segments. |
|
|
221 |
— |
17 |
— |
— |
))opening« |
— |
- |
aperture. |
|
|
241 |
— |
16 |
— |
— |
»Journal« |
- |
Quart. .Journal. |
||
|
242 |
-- |
10 |
— |
»M. Gillivra}'" |
- |
Mac Gillivray. |
|||
|
253 |
- |
8 |
— |
— |
»joints« |
— |
- |
internodes. |
|
|
253 |
— |
15 |
— |
— |
»joint« |
— |
- |
internode. |
|
|
253 |
— |
9 |
— |
— |
»base« |
— |
- |
beginning. |
|
|
253 |
— |
3 |
below |
)>(killoporelkiu |
- |
Caloporella. |
|||
|
253 |
fool-nole No |
. 1 |
8 |
- |
18. |
||||
|
254 |
line |
3 |
from |
below |
»joint« |
- |
internode. |
||
|
258 |
— |
6 |
— |
above |
))l*roce(l.« |
-- |
- |
Proceed. |
|
|
259 |
— |
10 |
- |
— |
))Ba.ss Straits* |
— |
- |
Bass' Strait. |
|
|
260 |
— |
6 |
— |
— |
»a pore« |
— |
- |
an ascopore. |
|
|
200 |
— |
9 |
— |
— |
192 |
— |
- |
172. |
|
|
261 |
fool |
:-n() |
le No |
. 1 |
48 |
— |
- |
46. |
|
|
264 line |
10 |
from |
above |
)>pore« |
— |
- |
ascopore. |
||
|
266. |
To the svn |
onvmv ' |
of Crepidacantha |
Poissot |
ii, \ |
,'ar. crinisnina mav be added: |
Lepralia Poissoni Norman, .Tourn. Linncan Soc., Zoology XXX, 1909, p. 307, PI. 41, figs. 7, 8.
Xlll should
))Part t« —
9() —
»P1. 15, figs. 13-14«
))oceria«
|
- 270 |
line 8 from above |
|
- 270 |
- 9 - - |
|
- 272 |
5 - - |
|
- 272 |
6&7 ^ |
|
- 281 |
11 below |
XVII. Part I. 165.
PI. 16, figs. 32 37. ooecia.
431
p. 282 line 14 from above »basc« should be proxim:il part.
- 297 — 16 — — ncrustaceumu — - Crustacea.
- 309 — 6 — below »conncction(( — - in connection.
- 313 — 10 — above kenoo(ecia<( — - kenozo(L'cia.
- 317. Figures showing the structure of tlie frontal wall in Anarthropora nioiiodoii
and Inversiula inversa are seen in PI. XXIII, figs. 10 a, 11 a.
- 320 line 11 from above i)triccuspisK should be triciispis.
- 321 — 16 — below ))specics,« — - species.
- 324 — 3 — above ))the the« — - the
- 353 — 7 — — ))endoocecial« — - endozocecial.
Mr. W. Lundbeck, the author of wDiptera Danicaw, has made me acquainted with the fact that the name »BicellariaK has been used already in 1823 for a genus of Hies bj' Mac- quart (Soc. Sci., Lille, 1823, 155), and I ])ropose therefore to change the Bryozoan name oBicrllariao into nBiccllariclkm and lo name the corresponding family nBicellarictlidaeu.
^B8^I^
1