« » THE DANISH INGOLF-EXPEDITION r-=1 VOL. V, PART 9. A CONTENTS: OSKAJ^ CARLGREN, ACTINIARIA. I. PUBLISHED AT THE COST OF THE GOVERNMENT BY I^^2 THE DIRECTION OF THE ZOOLOGICAL MUSEUM OF THE UNIVERSITY. <^- — , . == i-i '--— = CD ^ COPENHAGEN. H. HAGERUP. PRINTED BY BIANCO LUNO I92I. THE DANISH INGOLF-EXPEDITION VOLUME V. 9. v ACTINIARIA PART I. BY OSKAR CARLGREN. WITH 4 PLATES AND 210 FIGURES IN THE TEXT. -►•-<^3ix*r«CO"- COPENHAGEN. PRINTED BY BIANCO LUNO. 1921. The paper on the Actmiaria, of which I now present the first part, has been drawn up according to the same plan as m}^ reports on the Ceriantharia and Zoantharia of the Ingolf-Expedition. The main part of the material examined by myself belongs to the museums in Copenhagen and Stockholm. I have had at my disposal a rather great collection mainly enclosing the forms dredged by Romer and Schaudinn during their journey around the Spitzbergen, and I have also examined smaller collections from the museums in Upsala, Gothenburg, lyund, Christiania, Bergen, Drontheim, Troms0, Francfort on the Main and Petrograd. I beg to express my best thanks to all, who have supported my work through lending of material. The paper on the Ingolf-Actiniaria will be divided into four sections: i) Description of the species. 2) Sur\-ey of the hterature with critical notes on the arctic and northern Actiniaria. 3) Distribution of the species. 4) Contribution to the anatomy, genealogy and classification of the Actiniaria. In the present paper I have described all families occurring in the arctic and northern waters ex- cepting the forms which have been referred to the old family Sagartiidae. I have given special attention here to the size and distribution of the nematocysts and spirocysts. As before emphasized by me the .stinging capsules are of great importance to the classification. Nearly related genera show great agreement in the appearance and distribution of the nematocysts, and the species are often characterised by the difierent sizes of these latter, though in many cases the differences are not great. In fact I think that it is impossible to put up a good system of the Actiniaria without considering the stinging capsules. Concerning my statement of the breadth of the stinging capsules I will remark that it is approx- imate. 41882 Section I. Description of the species. Subtribus Protactininae. Family Gonactiniidae. Diagnosis: Protactininae with flattened, disclike, proximal body-end. Column of the same struc- ture as the tentacles with spirocysts and a more or less strongly developed, longitudinal muscle- and nerve- layer, not capable of involution. No distinct sphincter. lyongitudinal muscles of the tentacles ectodermal (in Gonactinia sometimes with a little tendency to be meso-ectodermal?) even as the radial muscles of the oral disc. Actinopharynx not rudimentary, with longitudinal muscles and often with spirocysts, with weak siphonogl)q)hes or without. Mesenteries typically arranged in cycles, each pair of mesenteries, except the directives, with the longitudinal muscles facing each other. 8 (the "Edwardsia--me.SQnX.QnQs"), 10 or 12 mesenteries perfect. Reproductive organs arranged in the usual manner, as a rule on all perfect mesenteries. Muscles of the mesenteries weak, especialh- the parieto-basilar nmscles. No ciliated lobes to the mesenterial filaments. Stomata absent or only the oral stomata present. In this family I have previously (1900) placed the genera Protanthea, Gonactinia and preliminarily also Boloceroides. Concerning the last genus, which has formerly been referred to the Boloceriidae, its affi- nity with Protanthea and Gonactinia has been admitted by Pax (1914 p. 608) and Poche (1914 p. 97), whereas Mc. Murrich (1904 p. 255) and later Stephenson (1918 p. 6) have not accepted it as belonging to the family Gonactiniidae. These latter authors, however, ha\-e not given any important arguments for their point of \'iew, no more have they refuted my objections against the affinity of the genus with the Bolo- ceriidae (vide Carlgren 1911). As I have pointed out, one of the differences between Protanthea and Go- nactinia on one side and Boloceroides on the other is that the former are devoid of ciliated streaks on the filaments, the latter not. In 1900 I also proposed to establish a special subfamily for the genus Boloceroides. Though I am continually of opinion that Boloceroides is nearly related to the above-mentioned species, I think that it may be the most practical to refer it with Bnnodeofsis and Alicia to the family Aliciidae, a heterogeneous family, as I will show in another paper. To the famil}' Gonactiniidae I furthermore refer the genus Sideractis. The diagnoses of this family and of the genera Protanthea and Gonactinia are a little altered and more detailed here. The Iiigolf-Expcdition. V. 9. 1 ACTINIARIA Genus Protanthea Caiigr. Diagnosis: Gonactiniidae with smooth column which is broader in the distal part than in the proximal one. I^ongitudinal muscle layer and nerve-stratum very well developed. Tentacles long, numerous, at the base a little constricted, in the apex not swollen. Oral disc conical. Only the 8 "Edwardsia-mesen- teries" perfect. All stronger mesenteries with filaments and reproductive organs. No differentiation into filament-mesenteries and genital-filament-mesenteries. Sterile, weak mesenteries in variable numbers in the distal part of the body. Protanthea simplex Carlgr. Protanthea simplex sp. n. Carlgren 1891 a p. 81, textfigs. — — Carlgr., Carlgren 1893 p. 24. PI. i figs. 9, 16, PI. 3. figs, i — 7, PI. 4. figs. 3 — 10. PI. 10. fig. 2. 1905 p. 158, Arndt 1912, p. 123, Grieg 1913, p. 143. Diagnosis: Body cup-like with 24 rather distinct, longitudinal furrows, without fossa. Margin undulated. Tentacles numerous from about 100 to 160 in 5 or 6 cycles, the inner ones about the length of the column or longer, the outer ones considerably shorter. Actinopharynx with numerous, weak, longitudi- nal furrows and 6 deeper of which 2 form the siphonoglyphes which are aborally prolongated. Pairs of fila- ment- and genital- mesenteries 6 + 6 = 12 in the whole length of the bod}'. Numerous sterile, filament- lacking mesenteries in the distal part of the body, in number corresponding to that of the tentacles. Lon- gitudinal muscles of the mesenteries weak, with low folds, form no pennons. Parieto-basilar muscles weak, not folded. No stomata. Nematocysts in the ectoderm of the column rib-like, partly 17 — 22 X 1,5 to 2 /i, partly 29 — 50 x 3 — 3,5 /i, in the tentacles partly 19 — 24 X 2 — 2,5 fi, partly 44 — 58 X 3,5 — 4 //, the latter very numerous and closely arranged in the distal part (batteries of stinging cells), in the actinopharynx 22 — 31 X 2 — 2,5 fjt. Spirocysts in the ectoderm of the column and tentacles from about 22 X 2,3 pt to 43 X 5 fi, very numerous in the column and in the proximal part of the tentacles, in the distal part of the latter more sparse. Actinopharynx without spirocysts. Colour: salmon-red, with tentacles a little paler, or white. Reproductive organs wliite or sal- mon-red. Dimensions: I,ength of the column to about 1,5 cm. Breadth of the oral disc to about 1,5 cm. Diameter of the pedal disc to about i cm. Occurrence: Sweden. Gullmarfiord (Saltkallefiord, Skarbergen, Borsas, Orstadhufvud, Humle- sacken) (Carlgren and others) from some few to 30 fathoms on Ascidiae, Serpula- and Chaetopterus tubes, rather common. Koster Isl. E. off Hamnholmen 80 — 100 m. Norway. Christianiafjord, Drobak (Carlgren 1899) Hardangerfiord, Jonanes, Straumastein 100 — ^400 m (teste Grieg), Oxen 100 — 150 fms. {Ashioinsen, laheUed Anthca cereiis), O-sterfiord (Appellof, teste Grieg). Drontheimfiord, Roberg 200 — 400 m. (Arwidsson, Arndt and others) Skarnsund 100 — 200 m on IvOphohelia (Oestergren, Arndt, Mortensen), lyofoten. Tysfiord 500 m on I^ophoheha (Nordgaard). ACTINIARIA In 1893 I have given a detailed description of this interesting, very primitive species, and therefore I here only add some statements especially concerning the size and distribution of the stinging capsules. The spirocysts in the ectoderm of the column are very numerous, their size variates from about 22 X 2,5 fi to 43 X 5 a. In the tentacles they are of about the same size as in the column, and numerous in the prox- imal part, but sparse in the apex, which condition evidently is correlated with the unequal occurrence of the nematocysts in these parts (compare below). In the ectoderm of the actinopharynx I have not found any spirocysts in maceration-preparations. In my description of the species 1893 I have also expressed my suspicion that the \ery few spirocysts I observed in this part probably are not normal components of the actinopharynx. In tlie ectoderm of the column the nematocysts are numerous and partly of a smaller type 17 — 22 X 1,5 //, partly of a larger one 29 — 50 X 3 — 3,5 ft. In the latter the basal part of the spiral thread is often discernible. Furthermore I have seen a few nematocysts with the thread thrown out. These cap- sules were of larger dimensions (60 — 80 X 4 — 4,5 u). In the tentacles I have also observed nematocysts of two unequal dimensions, partly 19 — 24 X 2 — 2,5 u, partly 44 — 58 X 3,5 — 4 //. The former are rather nu- merous, the latter very much so in the summit of the tentacles, where they are closely packed together, so that they completely intercept the view of all other nematocysts and cells, hereby causing the distal part of the tentacles to form strong stinging batteries. Further down on tlie tentacles these capsules are more sparse, although also here they generally occur, the spirocysts at the same time appearing in greater num- bers. The nematocysts of the actinopharynx are rather common and comparatively small (22 — 31 X 2 — 2,5 /^). Sometimes I have also here observed such large nematocysts as in the tentacles, but probably they have only been attached to the actinopharynx and belong to the tentacles. The basal part of the spiral thread is often discernible in the nematocysts of the actinopharynx. In expanded as well as sometimes in contracted state small papilliform elevations on the column are to be obser\'ed ("weisshche Flecke" Carlgren 1893) almost as in Sideractis, though here perhaps not so distinct. In these places the ectoderm is a little thickened, I liave, however, not found any real difference in the structure of the ectoderm of the papilhform elevations and of that of the grooves between them. The shallow furrows are not always distinct, especially when the actinopharynx is expanded. In larger specimens I have noticed a greater number of tentacles than before stated by me. Genus Gonactinia M. Sars. Diagnosis: Gonactiuiidae with smooth, cylindrical column. Margin not undulated. lyongitudinal muscle- and nerve-layer well developed. Tentacles long, few, at the base not constricted, not swollen in the apex. Oral disc flattened or conical. Perfect mesenteries 7 — 10, commonly 8 (the Edwardsia-mesen- teries"). The stronger mesenteries differentiated in filament-mesenteries and genital-filament- mesen- teries. The weaker mesenteries without filaments. Arrangement of the mesenteries often irregular, probably in connection with the reproduction by transverse partition. . ACTINIARIA Gonactinia prolifera (M. Sars.j Sars. Actinia prolijera n. sp. M. Sars 1835 p. 3, 11 PI. 2, fig. 6. Gonactinia prolifera Sars, M. Sars 1851 p. 142, 1853 p. 379, 386. Danielsen & Koren 1856 p. 87. Koren, 1857, p. 93. Andres, 1883, p. 366. Blochmann & Hilger, 1888, p. 385, PI. 14, 15. Haddon, 1889, p. 340, textfig. 2. Prouho, 1891, p. 247, PI. 9, figs, i — 3. Carlgren, 1893, p. 31, PI. I, fig. 14, PI. 4, figs. 11—13; 1904. P- 546, fig- I- Appellof, 1893, p. 27. 1895, p. II. Grieg, 1913, p. 143. Kerb, 1913, p. x. textfigs. 1—5. Pax, 1915. Diagnosis: Tentacles 14 — 18 commonly 16, of about the same length as the column, almost all of the same size. Actinopharj^nx of about half the length of the column with longitudinal furrows corres- ponding to the insertions of the mesenteries. Siphonoglyphes a little differentiated with aboral prolonga- tions. Spirocysts in the ectoderm of the column about 17 — 22 X 2,5 ^, in the tentacles 13 x i — 24 X 2,5 ji. Actinopharynx without spirocysts. Nematocysts in the ectoderm of the colunm about 17 — 29 x 2,5 — 3 fi, in the tentacles partly 22 — 24 X 2 ^, partly 29 — 43 X 3,5 — 4 //, the latter numerous in the distal part. Only the 4 lateral " Edwardsia-i-nesentenes" with both reproductive organs and filaments. Directive mesen- teries and often the 5th couple with filaments. Mesenteries of the second cycle only common in the dorsolateral exocoels. Arrangement of the mesenteries often irregular (compare above!). lyongitudinal muscles of the mesenteries and the parieto-basilar muscles very weak. No stomata. Colour: Flesh-coloured or white with transparent inner organs. Dimensions: Length of the column and the tentacles about 0,3 cm. Occurrence: Sweden. Gullmarfiord in several places attached to sea- weed, Serpula- tubes or mussel- shells (Carlgren). Vaderoarne (Zool. Stat. 1911) to shells of Lima, Kosterfiord. Hamnholmen 106 — 80 m. (Zool. Stat. 1910). North-Sea without distinct locahty (Uddstrom). Norway. Coast of Bergen, the islands off Bergen and the outer parts of the fiord. Sols\'ik Bergen 20 — 30 m (Kerb), Herlofiord (teste Appellof), Hardangerfiord, Straumastein, Saetvetnes 10 — 25 m (teste Grieg), Slaetholmen (M. Sars), Bougestrommen, Manger (M. Sars), Gibostad (Dons), Hammarfest M. Sars). Coast of Murman, Olenja Guba littoral (teste Pax). Further distribution: Mediterranean (Prouho). Remarks: This species has been described before in detail by Blochmann and Hilger 1888 and by myself 1893. Concermng the distribution and size of the stinging capsules I will state as follows : In the ectoderm of the column there are nematocysts as well as spirocysts, rather numerous, the size of the former variates from about 17 — 29 X 2,5 //, the latter from about 17 — 22 X 2,5 ^, possibly there are also smaller spirocysts, what I have not been able to decide. In the ectoderm of the tentacles the spirocysts appear everywhere in great numbers, they variate from about 13 x i /i to 24 X 2,5 /<. The nematocysts were of two different sizes, partly smaller and not so numerous, 22 — 24 x 2 ^, partly larger, 29 — 43 X 3,5 ,u. On one part of the latter the basal part of tlie spiral thread was discernible. As in Protanthca the greater part of the large nemato- cysts were concentrated in the summit of the tentacles, further down they were much fewer in numbers. The distal part of the tentacles also forms rather strong batteries of nematocysts. I have not been able ACTINIARIA to decide the size of the nematocysts in the actinopharynx, as it is very difficult to get positive maceration- preparations of the httle actinophar>'nx. Spirocysts appear to be absent here. In a pubhcation (1913) Kerb discusses the transversal partition of Gonactinia, and verifies as myself (1893) that the reproductive organs develop as well in the distal as in the proximal dividing pieces. Further- more he means having found that also the proximal piece divides transversely. I am, however, of opinion that liis experiments are not thorouglily proving. Kerb having started not from a chain of 3 indiduals, but only from one of 2 individuals. Under such circumstances it is therefore possible that the proximal piece dividing a second time was a middle piece, and not the primitive proximal piece of the chain. A chain of 3 individuals is namely to my mind very common in Gonactinia. (Carlgren 1904 p. 145. Kerb has evidently overlooked this paper). Thus of 10 transversely dividing specimens of Gonactinia, collected by Sars himself, no less than half the specimens were in tridivision, and yet Sars himself states having observed only a single one. In the above-mentioned paper I have tried to explain the reason why the chain of three indi- viduals is o\'erlooked. Besides it is possible that under \-erj' favourable circumstances the partition takes place so rapidly that the proximal piece is dropped before the middle piece is erected. In order to get a binding evidence that the most proximal piece divides again, it is necessary to follow the development of the division in a chain of 3 individuals. The experiments of Kerb only show that a proximal part is able to divide a second time, but leave undecided, whether it was a primitive proximal part or a middle piece that divided transversely. (iemis Sideractis Dan. Diagnosis: Gonactiniidae with weak muscularity, without sphincter. Colunm and actinopharynx with weak, ectodermal, longitudinal muscles extending into the indistinct pedal disc. Column with spiro- cysts, but without nematocysts. Tentacles hexamerously arranged at least to the stadium of 24 tentacles, conical, of ordinary length, the inner ones considerably longer than the outer ones. Apex of the tentacles hemispherical, smooth, with batteries of large, stinging capsules, the i^eduncle of the tentacles with small, papilliform elevations which also occur, though less numerously, on the oral disc and on the distal part of the column. Oral disc conical. Actinopharynx longitudinally sulcated, without differentiated siphonogly- phes. 6 pairs of perfect mesenteries with filaments, and fertile. Variable numbers of weak mesenteries, sterile and without filaments. Parieto-basilar muscles weak. Typical nematocysts absent. The above diagnosis of the genus completely differs from that given by Danielssen 1890. Above everytliing I must emphasize that the statement of Danielssen that the circular muscles are mesogloeal, is wrong. Besides, the description of the anatomical conditions by Danielssen is on several points erro- neous and very incomplete. After an examination of well preser\ed material, compared with that of Da- nielssen, the genus turned out to be a very primitive form belonging to the family Gonactiniidae. Danielssen has established the genus as a separate family, Sideractidae, which in his opinion would be related to the family Boloceriidae. Also Mc. Murrich (1893 p. 153) adopts this opinion. This is, however not the case, as the following description will clearly show. \'errill (1899 p. 143, 144) declares ACTINIAKIA that the genus probably belongs to the Paractidae. Now my suggestion (1902 p. 43) that the genus is related to the family Antheadae (Actiniidae) is correct — at the time of this statement I had only had the oppor- tunity of examining the most distal i^art of the original specimen in wliich only fragments of the column were left. In reality the genus is closely related to the family Gonactiniidae. It is true that it differs in several respects from Protanthea and Gonactinia, above all as regards the structure of the tentacles and the pre- sence of a greater number of perfect mesenteries, but in spite of these differences I think that it is not ne- cessary, at least not at present, to establish a special family for Sidcractis, which estabhshment in such a case would have to be founded for one thing on the structure of the tentacles and on the greater number of perfect mesenteries. Thus I refer Sideractis to the family Gonactiniidae together with Protanthea and Gonactinia. The genus contains only one known species, Sideractis glacialis Dan. Sideractis glacialis Dan. PI. I. Figs. 17 — 19. Sideractis glacialis n. sp. Danielssen 1890 p. 14. PI. i. fig. i. P. 7. figs. 10, 12. Diagnosis: Pedal disc wide, indistinct, with undulated border. Column with longitudinal furrows corresponding to the insertions of the mesenteries. Tentacles 24 — 38, in the stadium of 24 tentacles arranged in three cycles (6 + 6 + 12). Arrangement of the tentacles in later stadia more irregular through the de- \-elopment of new tentacles in the transversal plane (always?). Papilliform elevations composed of ecto- dermal thickenings, containing numerous spirocysts. Stinging capsules of several kinds in the apex of the tentacles, partly typical spirocysts, partly capsules with thread densely rolled-up (size: 86 — 106 X 12 — 14 //), partly of equal width with the basal part of the spiral thread distinct and of two different sizes 55 — 79 X 5 (I and 24 — 29 X 3 /i. Stinging capsules in the actinopharynx with thread densely rolled-up, 53 — 60 X 13 — 17 n, and others of equal width as those in the apex of the tentacles, 24 — 31 (seldom 46) X 5 — 6 [i. Colour: Almost transparent. Column and tentacles greenly .sliimmering, the oral disc redly so. Apex of the tentacles with a white anuulus. Actinopharynx and filaments pale red (Danielssen). Dimensions: In Hving state. Diameter of the pedal disc 2 cm. Height of the column 0,5 cm (Da- nielssen). In preserved state: i) The type specimen: Diameter of the oral disc 1,5 cm. IvCngth of the inner tentacles 0,6 cm breadth 0,25 cm, length of the outer tentacles 0,35 — 0,4 cm. 2) The best preser\'ed specimen from Sunde: Length of the column 0,4 cm, cone of the oral disc 0,15 in height. Inner tentacles 0,35, outer tentacles 0,2 cm. Occurrence: 70"4i' N. io°io' W. 263 fms. Temperature at the bottom -^- 0,3, brown clay with stones. (Norw. North-Atl. Exp. 1877) i sp. Norway. Sunde, mouth of the Hardangerfiord proper (G. O. Sars) 2 sp. Exterior aspect: The indistinct pedal disc was extended, thin and membranous in the original specimen, in one specimen from Sunde completely pulled off, in the other one (PI. i. figs. 17, 18) partly rather much damaged, and the filaments of one side pressed out. Though the preserving of it was anything but good, I do, however, tliink that I am able to decide that it was furnished with radial furrows. In sections through the pedal disc deep incisions, where the mesenteries inserate, are namely to be observed. Daniels- ACTINIARIA sen also says that the border of the pedal disc is undulated. The column is low or high according to the more or less contracted state of the body (the specimens from Sunde were Ijoth cylindrical and very much con- tracted). In the reproduced specimen (PI. i fig. 17) distinct, longitudinal furrows appear on the column; on the distal part one can see small, papilliform elevations of the same appearance as on the proximal parts of the tentacles, but these elevations are much more indistinct here than there, and sometimes not visible at all. The tentacles are of ordinary length, but broad. Their form is conical, in the apex the}- are hemi- spherical and smooth, while the larger, proximal part bears small, papilliform elevations, very- closely packed; in the extended, reproduced specimen and in the type specimen (PI. i. fig. 19) they are very distinct. On the other, ver>' contracted specimen from Sunde these elevations are not visible, neither on the tentacles nor on the oral disc or the column. The inner tentacles are considerably longer and broader than the outer ones. The reproduced specimen had 24 tentacles (6 — 6 — 12), the other specimen from Sunde 28. Besides the 24 tentacles arranged in the usual maimer there are on each side of the directive plane 2 tentacles de- veloped in the transversal plane (in the primary, lateral exocoels). Danielssen declares that liis specimen is provided with 32 tentacles, octomerously arranged. That is, however, not so, in fact there are 38 tentacles developed. On one side 18 tentacles namely appear, on the other 20. It is difficult to find out how the ten- tacles really are arranged, because of the bad presen-ation of the tj^pe specimen. I think, howevei", that on basis of my notes I can make the conclusion that the richer development of tentacles takes place mainly in the transversal plane. It is also possible that after the stadium of 24 tentacles another arrangement of the tentacles appears ; I am really more incUned to think that in the type specimen the arrangement is de- camerous iastead of octomerous. Perhaps this arrangement is only temporary', so that the animal after having reached the stadium of 48 tentacles (if it obtains so many) rearranges the tentacles hexamerously. Concern- ing the mesenteries I have observed such a rearrangement to take place in Condylactis georgiana (Carlgren 1898 p. II, 12). The oral disc is on the extended specimen conical, with the more or less .split-like mouth in the apex of the cone (PI. i, fig. 18). It is wide and furnished with radial furrows extending into the actinopharynx, whereby the margin of the mouth becomes of an indistinctly crenellated appearance. On the oral disc we find the same papilliform elevations as on the tentacles, though they are smaller and more indistinct. The actinopharynx is longitudinally sulcated. Danielssen declares that there are 8 furrows, on the specimens from Sunde there are about 14. The furrows in the directive plane differ in no respect from the others. Anatomical description. Only the distal part of the original specimen remained after the ex- amination by Danielssen, and even of this a large piece was not well preser\red. For the anatomical ex- amination I have cut out a piece with 4 tentacles. Furthermore I have sectionised the best conserved spec- imen from Sunde, mostly transversally. The pedal disc possesses, judging from the specimen from Sunde, a thick ectoderm containing nu- merous mucus-cells. Whether spirocysts occur also here I cannot decide, as maceration-preparations do not give any positive result, because of the unfavourable conser^^ation and the sticking of the filaments to the pedal disc. On the other hand I have in sections found nematocysts agreeing with both smaller kinds of ACTINIARIA Fig- I. Fig. 2. Fig 3. Fig. 4. I'ig. 5. Sideractis glacialis. Textfig. i. Transversal section through one part of the cohimn {co), a perfect and an imperfect mesentery at the transition of the actinopharynx in the filaments. Fig. 2. Longitudinal section through the distal part of a tentacle. Fig. 3. Transversal section through the actinopharynx and the bases of the mesenteries (me). Fig. 4. Part of the tentacle in section, showing the papillae containing spirocvsts. Fig. 5. Transversal section through the peduncle of a tentacle. ACTINIARIA these in the filaments. If spirocysts really are present, they are at any rate \-ery rare. The ectoderm of the pedal disc is provided with very weak, radial nuiscles. The mesogloea is thin and only at the inser- tions of the mesenteries very nmch thickened. It is homogeneous, witli sparsely scattered and ramificated cells, the mesogloea has, however, this appearance in all parts of the body. The ectoderm of the column is of equal height and contains, in addition to the supporting cells, numerous mucus-cells, while I have not observed any granulous gland-cells. It ought to be mentioned that no such cells have been discovered by me in the ectoderm of the tentacles or in the oral disc, only in the filaments and very sparsely in the ectoderm of the actinopharynx they seem to be present. Typical spiro- cysts are found in the ectoderm of the colunm, in the small elevations of the distal part they are most nu- merous, in the proximal part more sparse. The papiUiform elevations are almost exclusively thickenings of the ectoderm, only in a small degree the mesogloea takes part in the composition of the papillae which contain very numerous, densely packed spirocysts; the jiarts of the ectoderm between the papillae are on the other side more destitute of spirocysts. At the base of the ectoderm there is a weak stratum of nerve-fibrillae and nerve-cells and also a distinct, though weak layer of longitudinal nmscles (textfig. i) which are especially conspicuous in preparations stained with iron-haematoxylin. The mesogloea is rather thick ))etween the furrows, while Danielssen says that it is thin. This difference must, however, certainly be referred to the unequal state of contraction of the type specimen and of the specimen from Sunde, examined more in detail by myself. The inner part of the mesogloea is homogeneous here as also in the mesenteries; in the outer parts cells and now and then fibrillae are scattered or accumulated. Danielssen has interpreted the fibrillae as mesogloeal, circular muscles. In reahty the circular muscles of the column are very weak and endodermal and form no spliincter. The endoderm is high and provided witli numerous nuicus-cells. The ectoderm is higher in the smooth, hemispherical ends of the tentacles than in the the other part of the tentacles which is set with elevations, and much thicker than tlie mesogloea, and in all places of the same height (textfig. 2). It is characteristic by its abundance of stinging capsules, l)y wliicli the apex of the tentacles form strong batteries. In addition to connnon s]nrocysts of the same appearance as those of tlie column there are large stinging capsules with densely rolled-up thread and of considerable size (86 — 108 X 12 — 14 n — sometimes there are still larger capsules). Besides, I ha\e here observed very large, irre- gularly formed capsules, of a granulate appearance and of variable length which are probably stages of development of the former. I have namely found capsules of an intermediate shape, that is to saj"^ capsules which in form and granulation agree with the latter, but in the appearance of tlie spiral tliread with the former. All these capsules are. however, rather rare, wliereas another sort of capsules is very common. They are drawn out, of equal width, with distinct basal part to the spiral thread and much thinner than the large spirocysts (55 — yy x 5 //). Their thread is very twisted and its windings, close by the basal part, very di- stinct. Stages of development of these capsules with indiscernible thread are also found. At last there ap- pear smaller capsules of the same appearance as the drawn-out capsules but of smaller sizes (24 — 29 X about 3 fi). The stratum of ner\-e-fibrillae is distinct, but not thick, the muscles of the ecto- and endoderm weak. The mesogloea is mostly very thin, the endoderm thick. The proximal part of the tentacles, carrying elevations, is built just as the distal part of the column. The spirocysts are verA- numerous in the elevations The Ingolf-Expediunn. V. 9. 2 jQ ACTINIARIA (textfig. 4), mucus-cells are here also rather common, though rarer in the apex of the tentacles. The mesogloea is thick, irregularly and grossly folded and of the same structure as in the column. The endoderm is thinner than the other layers, the endodermal muscles weak. The oral disc is built as the proximal parts of the tentacles, the elevations are, however, not as densely packed. The radial muscles are a little stronger than the longitudinal muscles of the tentacles, and the mesogloea not as mucli folded as there. The ectoderm of the actinopharynx makes several folds (compare above), supported by thick balks of the mesogloea (textfig. j). In addition to numerous supporting cells mucus-cells are rather commonly found in the ectoderm of the actinopharynx, but granular gland-cells very rarely — in maceration-prepara- tions I have only observed few of these latter — furthermore stinging capsules, partly some uncommonly large with strongly twisted thread of the same appearance as those in the tentacles, but a little shorter (53 — -60 X 13 — 17 n), partl}^ smaller ones, almost equally wide and with distinct basal part to the spiral thread (24 — 31 X 5 — 6 /i. Very seldom I have observed still larger ones of the same kind (46 X 5 ju) ; I have also found stinging capsules in different stages of development (compare above). The nerve-layer and the longitudinal muscles are ver>' weak, the mesogloea in the longitudinal ridges thick, and endoderm of the same appear- ance as in the column. No differentiated siphonoglyphes. The number of mesenteries in the sectionised specimen from Sunde was 24, of which 6 pairs were perfect, and of these 2 pairs of directives. The twelve mesenteries of the second cycle were regularly deve- loped. They are thin and rise a little out of the column, only in the distal part they are stronger. Daniels- sen says that there are 16 pairs of perfect and 16 pairs of imperfect mesenteries in the type-specimen. This is, a priori, rather unlikely as the animal liad only 38 tentacles. Danielssen is certainly erring here as so many times before. Nevertheless a third imperfect cycle might be present as well in the type-specimen as in the second specimen from Sunde, in as much as more than 24 tentacles occur in both specimens. The muscles of the mesenteries are very weak. The longitudinal muscles are attached to large folds of the meso- gloea, (textfig. i), the parieto-basilar nuiscles are not folded, and basilar muscles lacking. The mesogloea is thick in the upper part, tliin in the lower one, and only at the insertions of the mesenteries it is thickened. The endoderm is rather high witli numerous nmcus-cells. The filaments of the mesenteries are simple, without ciliated lobes, and join only on the mesenteries of the first cycle. They enter into the ridges of the actinopharynx without any direct limit (textfig. i), their structure even much corresponding to that of the actinopharynx. They are very meandiian and of con- siderable diameter. The gland-cells are rather rare, especially the nmcus-cells: the supporting cells nume- rous, in sections with densely packed nuclei as in the ectoderm of the actinopharynx. The stinging capsules are like those of the actinopharynx. The larger ones with twisted thread are rather rare and 41 — 62 fi long and about 17 fi broad. Also of these latter I have observed stages of development. They are of variable size and show the same structure as the stinging capsules in the apex of the tentacles. The tliinner capsules of equal width are also rather rare and 24 — 31 /i long and about 7 ^ broad. Besides, I have seen some smaller capsules of the same kind (17 — 19 x 4 //). In transversal sections the mesogloea shows a T-like appearance. No endodermal limit-streak is found. ACTINIARIA II The examined species from Sunde was a male with well developed spermatozoa. Only the 6 first mesenteries are fertile. The information, given by Danielssen, that the reproductive organs appear in the imperfect mesenteries, needs confirming. Family Ptychodactiidae. Diagnosis: Protactininae with pedal disc not well defined from the column. I' well with the description which Appellof gives of the species, and very much resembles the specimen reproduced in fig. i in the paper by Appellof, though the body is a httle higher (PI. 3. fig. 6) and the mouth is almost closed and sourrounded by a wall rising above the other part of the oral disc. From the upper rim of this wall (opening of the mouth?) to the lower end of the actinopharynx the distance is 0,35 — 0,45 cm (in reality the distance is a little greater, as the undermost part of the actinopharynx is bent outward). The whole thing looks as if the actinopharj-nx is much longer than stated by Appellof. As how- ever no distinct limit exists between the oral disc and the actinopharynx — the ectodermal radial muscles and the radial furrows on the oral disc are prolongated as longitudinal nmscles resp. longitudinal furrows into the actinopharynx (a factum already emphasized by Appellof) and tlie occurrence and the size of the .stinging capsules are the same in l)oth regions — it is almost impossible to decide, where the actino- pharynx begins. If we are of the same opinion as Appellof and regards the actinopharymx as reduced to a thin joint, the animal has tlie capability — as the Ingolf-specimen shows — of turning down the central parts of the oral disc, so that they look like the actinopharynx, and "the mouth" is not on the rim of the actinopharynx, but completely surrounded by the oral disc. If in opposition to tliis we consider that the actinopharynx begins at the "mouth", the actinopharynx is nowise as much reduced as Appellof assures, though on such a supposition certainly short. I therefore hold it best to modify a little the diagnosis of the genus concerning the length of the actinopharynx. Furthermore the actinopharynx of the Ingolf-specimen shows the same appearance as that of the specimen described by Appellof, the prolongations of the ac- tinopharynx on the mesenteries are however not as strongly folded in the former. Concerning the inner organisation I cannot give any information of the arrangement of tlie mesenteries as I have not found it desirable to totally sectionise the specimen. The half-funnel-shaped formations on the imperfect mesen- teries agree in their structure with those described by me before (19 14). The glandular streaks were very meandrian, and the slightly developed reproductive organs were hmited to the lower parts of the mesen- ACTINXARIA j^ teries under the glandular streaks. The longitudinal muscles of the column were distinct, though they do not seem to form a continuous lamella. The spirocysts of the tentacles were rare and about 14 — 17 x 2,5 // in size, those of the column and of the oral disc very uncommon — after much searching in the maceration- preparations I found only one spirocyst in the column and one pair in the oral disc. Also the nematocysts are not particularly numerous and, Uke the spirocysts, they are of inconsiderable size, in the column 11 — 14 X 2,5 fi, in the tentacles 10 X 2 — 2,5 // to 19 X 3,5 // and in the actinopharynx 12 X 2,5 /u to 19 X 3,5 — 4,5 fi. The spiral thread is often discernible in the greater nematocysts of the tentacles and of the actino- pharynx. I have examined the stinging capsules as well in one of tiie type-specimens as in the Ingolf- specimen. Family Halcuyiidae (Endocoelactiidae) . Diagnosis: Protactininae with pedal disc not well defined from the column. The ectoderm of the column as well as that of the actinopharynx with spirocysts, (spirocysts sometimes absent: in the column of Halcurias endocoelactis, teste Stephenson). Longitudinal muscles as a rule absent in the column (in Halcurias pilatus present, teste Mc. Murrich). No sphincter. Tentacles arranged either in two alternating cycles or in several such, very much displaced (18 + 10 + 16 + 8 + 16) and not arranged as in the typi- cal Actiniaria. Longitudinal muscles of the tentacles ectodermal, radial nmsdes of the oral disc ectodermal or with a little tendency to be mesogloeal (meso-ectodermal) . Actinopharynx strong with i — 2 siphono- glyphes. Mesenteries from the second cycle developed in the endocoels • — each pair of mesenteries with the longitudinal muscles facing away from each other — and arranged either cyclically, or, from the 20( — 28) mesentery-stage, bilaterally in 8 or in a few more development-zones. In the latter case each bilateral pair consists of a micro and a macro-mesenterium (or of two equally developed mesenteries?). I,ongitudinal muscles of the mesenteries mostly weak, sometimes forming pennons. All stronger mesenteries with repro- ductive organs. In this family I (1918) have included the genera Halcurias Mc. Murr. (= Endocoelactis Carlgr.), Synhalcurias Carlgr., Synactinernus Carlgr., Isacfinernus Carlgr. and Actinernus Verr. (= Porponia R. Hertw.). Compare this paper. To these genera Stephenson (1918b) adds a new genus, Carlgfenia which evidentlj' is nuich related to Halcurias and possibly might be referred to tliis genus. Concerning the species Halcurias endocoelactis, described by Stephenson (1918a), it is questionable if this species really is an Halcurias. The in certain respects incomplete description of the species, given by Stephenson, founded on his examination of a single specimen, seems to me to indicate that we have to do with a distinct genus. The arrangement of the mesenteries is not the typical //a/c/^^-ifls-distribution, but seems to be more irregular as in Synhalcurias. Probably the development of the later mesenteries resembles that in Actinernus and is also bilateral. It is, however, not quite identical as it looks as if the new mesenteries develop more unilaterally, in so much as the development-zones seem to be found on both sides of the 4 mesenteries of the second cycle. Judging from the description by Stephenson it forms a transition between the Halcurias- and the Ac- tinernus-ty-pes. Also the absence of the spirocysts in the column, if not overlooked bj- Stephenson, — (S. has examined the column only on sections and not on maceration-preparations which give the only cer- ,. ACTINIARIA 14 tain criteriuin if the spirocysts are \-ery rare or absent) — speaks for the opinion that this species may form the t}ye of a new genus, because all other known Halcuriidae have spirocysts in their column-ectoderm. I propose for this new genus the name Hakuriopsis and give here a preliminary diagnosis based on the description by Stephenson: Elongated Halcuriidae, not distally lobated. Column smooth without papillae and spirocysts. Ten- tacles short, conical, without thickenings of the mesogloea at the outer side of the base, comparatively few. Arrangement? Longitudinal muscles of the tentacles ectodermal, not strong. Only one siphonoglyphe. Mesenteries comparatively few, the older with strong muscle-pennons, to the stage of 20 mesenteries deve- loped as in Halcurias, from this stage new mesenteries originate, probably in only 8 development-zones on both sides of the 4 mesenteries of the second cycle. Both mesenteries of the same pair equivalent. Genus Actinernus Verr. Diagnosis: Halcuriidae with thick cyhndrical body, in the distal part more or less increasing in breadth and often forming distinct lobes conmionly 8 in number. Sometimes these lobes are only indicated or wanting in young individuals. Tentacles of ordinary length, conical or cylindrical, excepting the youngest (and in A. elongatus also the inner ones?) cannot be covered by the column; on the outer side with very thick mesogloea which continues bridgelike in the mesogloea of the column. Tlie arrangement of the tentacles more or less distinct, not frequently Uke that of Halcurias. For the greater part the tentacles are concen- trated in two cycles with the largest tentacles in the apex of the lobes. Oral disc wide, especially where di- stinct lobes are present, more narrow between the lobes, with weak, radial ridges and shallow furrows between. Actinopharynx well developed with rather numerous, deep, longitudinal furrows and 2 broad siphonoglyphes, to which several mesenteries are attached. Mesenteries numerous, arranged in the begin- ning as the older mesenteries of Halcurias, after the stage of 20 mesenteries or a little later the mesenteries originate bilaterally, in 8 or some more development-zones, situated between the distal lobes. The develop- ment of the mesenteries goes on mostly from the edges of the endocoels towards their middle. The bilateral pairs consisting each of one micro- and one macro-mesenterium. Dioecious. Actinernus nobilis Verr. Actinernus nobilis n. sp. Verrill 1879 P- 474- — — Verr. Verrill 1885 p. 534 fig. 23, Andres 1883 p. 584. Carlgren 1914 p. 70. 1818 p. 32 textligs. 8 — ^10, 25. Diagnosis: Body cup-hke, short, toward the distal part forming 4 greater and 4 smaller, alter- nate lobes. The lobes sometimes (often?) show a tendency to di\'ide into feeble, indistinct, secondary lobes. Mesogloea-bridges on the outer side of the tentacles broad, somewhat depressed from without inwards, teeth- like, rather short and sharp-pointed in the apex. Distal parts of the tentacles of normal appearance, conical, in the summit pointed, not sulcated, or feebly lengthwise so. Arrangements of the tentacles indistinct, at ACTINIARIA j^ least in two cycles. Number of tentacles to about 120. The thick-walled nematocysts in the ectoderm of the pedal disc 25 — 31 (36) x 2,5 /i, those of the column 24—38 X 2—2,5 (3) ^. those of the tentacles partly 38 — 61 X 2,5 — 4 n, partly 22 — 29 X 2 //, those of the actinopharynx 34 — 41 x 2,5 fi. Spirocysts in the column commonly 31 — ^48 x 5 ,«, sometimes larger, those in the tentacles of variable size, the largest up to 67 X 7 [i, those in the actinopharynx about as those in the tentacles. Arrangement of the mesenteries bilateral after the stage of 20 — 28 mesenteries. I^ongitudinal muscles of the tentacles comparatively weak, radial muscles of the oral disc somewhat stronger, both of these ectodermal. I,ongitudinal muscles of the mesenteries not strong, form no distinct pennons. Parieto-basilar muscles weak. Colour: In recently preserved state: oral disc and tentacles deep purj^hsh brown, with radiating lines of paler colour on the oral disc, mouth (actinopharynx) deep brown inside, sides of body milk-white with traces of orange-colour wliere the outer coat remains (Verrill). Dimensions: Up to 10 cm broad and 7,5 cm high in preserved state (Verrill). Occurrence: Da\as Strait 63°3o'N. 54°24' W. 582 fms. Temperature at the bottom 3,3° (In- golf-Exp. St. 25). Further distribution: North-Atlantic. Northern part of U. S. A. from deep water rare, common at Nova Scotia from a depth of 200 — 300 fathoms (Verrill). This species I have described in detail in 1918, wherefore I now only give a diagnosis of the same. Subtribus Nynactininae. Athenaria s. Abasilaria. The group Athenaria (Carlgren 1898), or more distinctly termed Abasilaria (Carlgren 1905), differs from the more differentiated Actiniaria, Thenaria or Basilaria, through the character that the basilar muscles are wanting in the former, present in the latter, and includes almost all the old groups, Actinines pivotantes, proposed by Milne-Edwards 1857, ^"^^ the family Ilyanthidae established by Cxosse 1858, excepting the genera which afterwards proved to belong to quite different Anthozoa, such as Sphenopus, Arachnactis and Cerianthus. I am of opinion that in the system of Gosse 1858 we also find no less than four families of Athenaria represented, the Edwardsiidae b}' the genus Edwardsia, the Halcampidae by Halcampa, the Halcampoididae bj- Pcachia and the Ilyanthidae by Ilyanthus. Besides these famiUes I include in the group the famihes lyimnactiniidae n. fam., Andwakiidae and Halcampactiidae which certainly would have been referred to the Actinines pivotantes or Ih^anthidae, if they had been known at the time of the fonnatiou of these groups. The diagnoses which different authors have given of these groups are namely such that the}' in reality almost correspond with the character of the group which I have called Athenaria. Thus Milne-Edwards characterizes his Actinines pivotantes as follows. "Especes dont le pied est tres petit et le corps fort allonge", and Gosse his family Ilyanthidae in the following manner. "Corporis extremitas inferior obtuse rotundata sine basi adhaerente ....". Other authors, ha\'ing used the group to about the same extent, give the following diagnosis of it. "Column elongated, tapering below to a pointed or rounded l6 ACTINIARIA base, without a distinct disc .... (Verrill 1864)", "Actinianae liberae basi muscvilari carentes" (Andres 1880), "Korper verlangert wunu- oder saulenformig, liinten zugespitzt, nicht scheibenartig verbreitet und daher nicht festheftend, nur in Sand vergraben" (Klunzinger 1877), "Hexactinien mit abgerundetem aboralen Korperende ohne Fussscheibe" (R. Hertwig 1882). Thus the absence of a real pedal disc is the main character wliich these authors have given the Actinines pivotantes or Ilyanthidae, the same character which distinguishes the Athenaria, still with the difference that the absence of the basilar muscles is the principal character, while the shape of the proximal body-end, if pointed, rounded or flattened disc-shaped, is of little importance as pointed out by me (1905 p. 517), though it is true that most Athenaria commonly show a rounded-proximal body-end. This part is namely in certain species able to alter its shape, f. inst. Milne-Edwardsia loveni alters the shape of its proximal end in accordance with the \-ariation of the canals in the dead lyophohelia-stocks, and the commonly rounded or a little flattened proximal end of Milnc- Edwardsia carnea is capable of flattening out disc-like, so that it gets a considerable breadth, at the same time as the body becomes low and conical what I have observed in a specimen, the cuticle of which was dropped in the aquarium (Compare Milne-edwardsia carnea). Halianthella (= Marsupifer) has the same capabihty. A specimen of this latter, taken by the German deep-sea expedition was namely almost cake- Uke and reminded of a very contracted Thenaria with a real pedal disc (with basilar muscles). The aboral, flattened end was attached to a stone. Under such circumstances there is nothing at all to prevent referring to the Athenaria such a genus as Octincon which is devoid of basilar muscles, and the proximal body-end of which forms a wide, basal plate incrusted with sand. The absence of basilar muscles is common to the Athenaria, Protactininae and Protostichodactylinae (Corallimorphidae, Discosomidae, Carlgren 1900). My suggestion to divide the Actininae into two groups, Athenaria and Thenaria, has been opposed by Mc. Murrich and Poche. Mc. Murrich (1904 p. 221) declares that this division in Athenaria and The- naria "tends to the confusion of unrelated forms and the separation of others which are nearly related", an idea which I showed (1905 p. 517) to have no foundation whatever, in as much as I pointed out that the opinion of Mc. Murrich that the basilar muscles of the Thenaria are homologous with the parietal nmscles of the Athenaria, on which he mainly supports his statement, is false. At the same time I reject the supposi- tion of Mc. Murrich that Haloclava and Eloactis would be Thenarians. Mc. Murrich prefers to divide the Actiniaria at once in families "recognizing in addition to the Edwardsiidae, which will include in addition to the Edwardsiae and Halcatnpidae (Auct.) the genus Scytophorus, the Gonactiniidae, which will include Gonactinia, Protanthea and possibly Oractis, the Peachiidae, including Peachia and Haloclava and the Ilyan- thidae having essentiallj' the limitations recognised by Andres (1883)." On further examination we find, however, that the enumerated forms are devoid of basilar muscles, while all other genera, described in the paper of Mc. Murrich 1904, are Thenarians. In the system of Pax (1914), which is for a great part based on my works, he begins by placing among Nynantheae the same families as I myself (1900 p. 24), and gives as first character "ohne Fussscheibe und Basilarmuskeln", while he continues by enumerating families which are mainly characterised by the presence of a well-developed pedal disc, (an exception being made by the free-swimming Minyadidae which belongs to the Stichodactylinae, owing to my examination (1914). ACTINIARIA 17 Under such circumstances it seems difficult to me to understand that it would be wrong, from a classificatory point of view, to comprehend aU families without basilar muscles in a large unity and all with basilar muscles in another. The absence of the basilar muscles is namely, as shown by me, a primitive character occurring only in lower Actiniaria, and moreover it is characteristic of theZoantharia (s. str.) andMadreporaria,the Antho- zoa, to which the Actiniaria are most nearlj' related. In those groups there is no real pedal disc but rather a basal plate of exactly the same nature as in Protanthea and Octineon. Thus as we find that several families are devoid of basilar muscles, wliile others have such, and as furthermore tliis lacking of basilar muscles is a primitive character which they have in common with Zoantharia and Madreporaria, the basilar muscles appearing only in the more differentiated Actiniaria, I cannot see that there is any ostensible reason against dividing the Nynactininae into Athenaria and Thenaria (Abasilaria and Basilaria). It would, of course, be different, if it was to be proved that forms without as well as with basilar muscles appeared in one family. In a single case genera without, and some with basilar muscles have in fact been referred to one family, namely the Aliciidae. In my opinion sucli a classification is not well founded, and the family is heterogeneous, as I have already stated (1900 p. 96) and will further discuss later on. The objection by Poche (1914 p. 96) that circumstances in the family Aliciidae prove the groups Athenaria — Thenaria to be untenable, is invalid. His other objection to my classification is no better; he namely writes: "Die Einwendungen Mc. Murrich's gegen die Unterscheidungen der Abteilungen Athenaria und Thenaria, die iui Wesentlichen auf das Fehlen bezw. Vorhandensein der Basilarmuskeln gegriindet ist, hat Carlgren allerdings zum Teil in befriedigender Weise widerlegt. So wird man seiner Bekampfung der von Mc. Murrich behaupteten Homologien der Basilar- mit den Parietahnuskeln gewiss beistimmen, ebenso seiner Zuritckweisung des auf Haloclava und Eloactis gegriindeten Einwandes. Unwiderlegt bleibt aber der Einwurf betreffs der nahen Zusammenstellung von Edwardsia und Halcampa einerseits, mit Ilyanthus andererseits." As far as I understand, Mc. Murrich in his paper (1904 p. 221) does not make any manifest objection especially to the placing of Ilyanthus near the Edwardsiidae, and even if he does object, I do not see his reason for it, Ilyanthus being no more a Thena- rian than Haloclava and Eloactis, but really an Athenarian. The occurrence of a rather well-developed, endodermal sphincter in Ilyanthus, in contradistinction to the weak, eudodermal muscles in Edwardsia forming no sphincter, does not speak against the classification proposed by myself. The nature of the sphincter is namely at most a family character. Mc. Murrich wrongly refers Halcampa with its mesogloeal sphincter to the Edwardsiidae, and Oractis which is pro\dded with a well-developed endodermal sphincter, together with the sphincter-lacking Protanthea and Gonactinia to the Gonactiniidae. If thus the establishment of the groups of Athenaria and Thenaria is well founded, it remains to make clear the extent of the different famihes which would have to be placed in the former group. The classification of the Actiniaria, lacking a pedal disc, varies considerably according to the different authors, in as much as some of them discern only one, others few or several famihes. The previous authors, such as Milne-Edwards (1857), Gosse (1858), Hincks (1861), Verrill (1864, 1868), Klunzinger {1877), Studer (1879), Andres (1880) place aU genera — those afterwards discovered I of course leave out of consideration — together in a single section or family Actinines pivotantes sc. Ilyantliidae. A later author, Faurot (1895) also uses the former term. Only in 1880 Andres distinguishes the Edwardsiidae as a separate family The Ingolf-Expedition. V. 9. 3 l8 ACTINIARIA which is acceptedb}^ Had don (1889) ; 1882 andi888 R.Hertwig however attributes a greater systematic impor- tance to tliis family, in as much as he estabhshes a tribus for the genus Edwardsia which is accepted among others by Mc.Murrich (1893) and Carlgren (1893) ; the latter divides the tribus into two families Edward- sidae and Milne-Edwardsidae. 1898 Carlgren again assigns to the tribus a lower systematical rank wliich it has later on generally kept. Mc. Murrich (1904 p. 232) even enlarges it, by placing in it not only the Edwardsia but also Scytophorus and Halcampidae (Auct.), and Delage and Herouard (1904) place in their subordo Edwardsina both the Edwardsinae and the Protantheinae [Gonactinia, Protanthea and Oractis). Disregarding the Edwardsiidae we find the other genera belonging to my Athenaria — I leave out of consideration some genera which have been placed in another family, such as Oractis — arranged in a single family Ilyanthidae with the subfamihes Halcampinae, Halcampomorphinae and Andwakianae in the paper of Carlgren (1893) and in that of Haddon (1897) — in the latter paper there are, however, only two sub- famihes, Halcampinae and Halianthinae, while R.Hertwig 1888 divides them into two families, Ilyanthidae and Siphonactinidae. Haddon (1889), however, places both Halcampa and Peachia {— Siphonactinia) in the family Halcampidae. In the work of Andres (1883) our Athenaria, except the Edwardsidae, is represented by four families, Halcampidae, Siphonactinidae, Mesacmeidae and Ilyantliidae, a division also used by Pennington (1885). — the Mesacmaeidae are, however, not mentioned here. Mc. Murrich (1893) disting- uishes 3 famiHes, Halcampidae, Ilyanthidae and Siphonactinidae, but some years later (1904) only 2, Ilyan- thidae and Peachiidae (= Siphonactinidae), while the Halcampids are placed with the Edwardsiidae. 1900 Carlgren divides the Athenaria, excepting the Edwardsiidae, in five families, Halcampomorphidae, Hal- campidae, Halcampactidae, Andwakiadae and Ilyantliidae, an arrangement which Pax accepts (1914 p. 609), though he, as well as other authors, does not make use of the term Athenaria. In a paper by Poclie (1914) we find almost the same f amihes, Peachiidae, Halcampidae, Halcampactiniidae, Andwakiidae and Ilyantliidae ; in the former the genera are, however, grouped in another way than in the systems of Carlgren and Pax. Stephenson recently (1918) uses the Ilyantliidae as originally defined, excepting, however, the Edwardsiidae. A curious division we find in the works of Delage and Herouard (1901), who regard the Edwardsina and Halcampina as suborders equivalent to the Actinina and Stichodactylina. The first group includes among others the family Edwardsinae, the second the families Halcampinae and Monaulinae, which latter Hertwig (1882) refers to a separate tribus Monauleae, while the Ilyanthinae and the Mesacmaeinae are placed in the third group. From which point of view shall we classify my Athenaria viz. mainly the old groups Actinines pivo- tantes sc. Ilyanthidae (s. lat.) ? That it is necessary to separate the genera provided with acontia, from the other genera, hardly needs further discussion, and would not likely be denied by any recent author. As some Athenaria provided with acontia lack a sphincter, while others have a distinct mesogloeal one, it may be practical to divide them into two famihes, Halcampactiidae (Halcampactiniidae) and Andwakiidae, in the same way as we separate the two families Actiniidae and Paractiidae of the Thenaria, on account of the nature of the spliincter. Unfortunately only Pax and Poche have clearly stated their view concerning this question and adopted my opinion. On the other hand, it is necessary further to discuss the arrangement ACTINIARIA iQ of the forms without acontia. Are the Edwardsids to be placed together with the Halcampids, as proposed by Me. Murrich; are the Siphonactinids = Peachiidae to form a particular family; are the Halcampids (s.lat.) with raesogloeal sphincter, and those lacking one, to be united in a single family; and finaUj', is a par- ticular family to be established for the genus Ilyanthus ? Concerning the first question, which is closely con- nected with the tliird, I must at any rate positively refuse the attempt to place the Edwardsids together with forms provided with a mesogloeal sphincter, viz. the Halcampids (s. str.). The only principal point of view for the arrangement of the other Athenaria is namely, in my opinion, the structure of the sphincter and its occurrence. Most of these forms are devoid of sphincter, some have a mesogloeal and a few a rather weU- developed, endodermal one. Why should we not apply this feature as a basis of classification in this case, when in the more differentiated Actiniaria with basilar muscles we lay so much stress, and with full right, on the appearance of the sphincter as a basis for the arrangement of the families ? We distinguish the family Actiniidae from the Paractiidae mainly by the structure of the spliincter, in as much as the sphincter is lacking or endodermal in the first family, but mesogloeal in the second. If for instance the genus Paractis should turn out to be provided with an endodermal sphincter instead of a mesogloeal one, it would no doubt by all authors be referred to the family Actiniidae. As we cannot suppose that the mesogloeal sphincter is developed in another way in the Athenaria than in the more differentiated Actiniaria — I at least cannot find anytliing tending to prove that the mesogloeal sphincter of the Halcampids variates, so as to make it now endodermal, now mesogloeal, with transitory stages between^; in the genera Halcampa, Parahalcampa and Cactosoma the sphincter is mesogloeal and conspicuous, in Halianthella strong and even double — it seems most consistent to me to separate the acontia-lacking Athenaria, provided with a mesogloeal sphincter from the other forms, and to place them in a separate family, Halcampidae. Thus I cannot adopt the classification neither of Mc. Murrich nor of Poche, who do not see any reason in the character of the sphincter for the formation of a family Halcampidae, based on the occurrence of a mesogloeal sphincter. Besides, how inconsistent Poche is in keeping the family Ilyanthidae, based on the occurrence of a diffus-circumscript endodermal sphincter, while he separates the two with acontia provided famihes, Andwakiidae and Halcampactiniidae, though the only difference between these latter consists in the former having a mesogloeal sphincter, the latter none. The family Halcampidae, based on the presence of a mesogloeal sphincter, must therefore be maintained. Concerning the family Ilyantliidae s. str., it might possibly be placed together with some of the re- maining forms (the family Halcampoididae) , as forms with an endodermal spliincter are rather to be referred to forms with no spliincter. I do, however, think that it is more practical to keep this family. To the family Peacluidae (Siphonactiniidae) the genera Peachia, Eloactis and Haloclava are referred. The characters on which the family might be based are as foUows: i) the bilateral arrangement of the 20 ' According to several authors the genus Aiptasia has no sphincter or is provided with now an endodermal, now a raesogloeal one. For the species with a mesogloeal sphincter Stephenson (1918 p. 51) has proposed a special genus Aiptasioides with the species prima and pallida which he refers to the subfamily Metridinae. Though I have no particular knowledge of these genera, I would be inclined to go still further and place the genus Aiplasia in a special family Aiptasiidae. The whole family Sagartiidae besides needs a radical revision, some species of Phellia probablj' belong to the Andwakiidae. Since this paper was written, Stephenson in a paper (1920 Quart. Joiirn. Mic. Sc. 64) has divided the Sagartians into several families. I agree with him that the Sagartians are not a homogeneous group, and with Bourne (Quart. Journ. Mic. Sc. 63, 1919) that they are of different origin. In the second part of this work I will further discuss this question. 3* 20 ACTINIARIA mesenteries (the checked development of the dorsolateral mesenteries of the second cycle) 2) the presence of a single, well-developed siphonoglj^Dhe and 3) the arrangement of the tentacles : the inner endocoel- tentacles are shorter than the outer exocoel-tentacles (compare Carlgren 1904 p. 544). There is no doubt that the above-named genera are nearly related to each other, but it is a question, if these genera alone ought to be placed in a particular family. Leaving Oractis out of consideration, the position of which I will further discuss later on, we find a bilateral symmetry, though of a somewhat different type in the Edwardsids, in Pentactinia — where the number of mesenteries is the same as in Peachia, but the ventrolateral mesenteries of the second order not developed, while in Peachia the corresponding, dorsolateral mesenteries are missing, in Parahal- campa and Limnactinia, and at last probably also in Siphonactinopsis, the mesenteries of which are twice as many as in Peachia. A single, ventral siphonoglyphe is also present on most, perhaps all Edwardsids, though it is only a little differentiated, furthermore in Pentactinia, Harenactis, Mesacmaea, Scytophorus and Parahalcampa. The same arrangement of the tentacles as in Peachia we observe in several Edwardsids, namely in the subfamily Edwardsiinae, while in theMilne-edwardsiinae and the other genera the inner tentacles are longer than the outer ones, or all tentacles of about the same length. Only the arrangement of the mesen- teries is thus specifically characteristic of Peachia, Haloclava and Eloactis, in as much as there are 10 pairs of mesenteries, while the dorsolateral mesenteries of the second order are missing, an arrangement which possibly they have in common with Siphonactinopsis, though there are twice as many in the latter. However much the arrangement of the mesenteries varies in the Athenaria I will call the attention to the fact that Scytophorus has onlj^ 14 mesenteries, and therefore I do not think it justifiable to estabHsh a separate family for Peachia, Eloactis and Haloclava on account of the number and position of the mesenteries. The maintain- ing of the family Monaulidae and the establishing of several families owing to the arrangement of the mesen- teries are the logical consequences of these facts. If we keep to the arrangement of the tentacles, it would be much more justifiable to place the subfamily Edwardsiinae together with Peachia, Haloclava and Eloactis in a family Edwardsiidae, and the subfamily Milne-edwardsiinae together with the other acontia- and sphincter-lacking Athenaria in another one. As it is, however, possible that this conformity in the arrangement of the tentacles in the Edwardsiinae Peachia, etc. may depend on a convergence ^, caused by their having parasitic larvae (observed among the genus Edwardsia and Peachia), I provisionally place the subfamilies Edwardsiinae and Milne-edwardsiinae as before in a single family, Edwardsiidae, while the other acontia- and sphincter-lacking Athenaria are referred to a family which I call Halcanipoididae after Halcampoides, the most primitive genus. (Halcam- poididae, proposed as a subfamily by Appell5f (i8g6), is synonymous with my family HalcampomoriDhidae which must be dropped, according to the international rules). Thus I provisionally refer to the Athenaria the same families as in 1900, only adding the new family Limnactiniidae, and with the difference that the name Halcampomorphidae is exchanged for Halcanipoididae. Consequently the arrangement of the genera in the different families is as follows: ' I seize the opportunity to rectify an error, slipped in while my paper (1900 b) was being printed. Page 544, the first note has "nicht wahrscheinlich" for, in my manuscript "recht wahrscheinlich." ACTINIARIA 21 Fam. Halcampoididae Fam. Edwardsiidae Subfatn. Edwardsiinae Genera. Edwardsia Quatr. Isoedwardsia Carlgr. Subfam. Milne-edwardsiinae . . . Genera. Milne-edwardsia Carlgr. Paraedwardsia Carlgr. Genera. Halcampoides Dan., Acthelmis Liitk., Phytocoetes- Ann., Halcampclla Andr., Synhalcampella^ Carlgr., Scytophorus R. Hertw., Pentactinia Carlgr., Harenaciis Torr., Siphonactinopsis Carlgr. Mesacmaea Andr., Peachia Gosse, Eloaclis Andr., Haloclava Verr., PPolyopis R. Hertw. Genera. Limnactinia Carlgr., PPolyopis R. Hertw. Genera. Halcampa Gosse, Parahalcampa Carlgr., Synhalcampa- Carlgr., Cacto- soma Dan., Mena'^ Steph., Halianthella Kwietn. Fam. Halcampactiidae. Genera. Halcampactis 'Parquh., Haliactis Cailgi. , Pelocoetes Ann.^, Pllyactis Andi., POctophdlia Andr. Fam. Andwakiidae. Genera. Andwakia Dan., Octineon Mosel, Pllyactis Andr., POdophellia Andr. Fam. Ilyanthidae. Genera. Ilyanthus Forb., Oractis Mc. Murr. Fam. Limuactiniidae Fam. Halcampidae. In the following I will further discuss the position of the genera within the families of which I have mentioned the first six here. Concerning the position of the genus Oractis I am a Uttle doubtful. It is true that, according to me, it cannot be placed in the family Gonactiniidae, as proposed byMc. Murrich, because it is only in the arrangement of the mesenteries that it partly agrees with this familj', while it differs essenti- ally from it in the other characters. The only families which are to be considered in the placing of this genus are the Halcampoididae and the Ilyanthidae. The endodermal sphincter which is, in proportion to the small 1 Compare the family Halcampoididae. ^ Since this was written Stephenson (1920 p. 520) has proposed a new family provided with acontia, Diadumcuidae, enclosing Diadumene Ann, Pelocoetes Ann., Phytocoetes Ann., and Mena Steph. The family is ccrtainl)' heterogeneous. The type- genus differs in several respects from the three others. The former has a well-developed pedal disc and certainly belongs to the BasUaria, while the three latter probablj' are Abasilaria. (It is probably a lapsus of Annandale when he (1915 p. 81) speaks of basilar muscles instead of parietal rau.scles). In consequence of .A.nnandale's description of their structure it seems to me that Pelocoetes would belong to the Halcampactiidae, Phytocoetes and Mena to the .\ndwakiidae. But on fiu-ther examination of .An- nandale's figure 3 (p. 80) in which the acontia are also represented, I think that at least Phytocoetes gangicus is not provided with acontia. The figure designated as acontia is namely no such thing, but simply mesenterial filaments. Thus Phytocoetes is a Halcampoid and nearly related to Acthelmis. Concerning Mena {Phytocoetes) c/n7Aaea I am of opinion that this species is a Cac/o- soma. Nothing in the structure speaks against it ; on the contrary the appearance of the sphincter and the presence of papillae on the column indicate that we have to do with this genus. At least it is closely related to this genus. Finally Pelocoetes is a good genus and probably belonging to the Halcampactiidae. Though .\nuandale has not given any figure of the acontia, but says that they are long and relatively stout, it is probable that in this case he has not mistaken the mesenterial filaments for acontia. The species Halianthus limnicola Ann. is, though a Halcampid, probably the type of a new genus. It is neither a Hal- campa nor a Cactosoma. The absence of secondary, imperfect mesenteries in the whole length or almost so of the column and the pres- ence of 12 rows of tubercles on the coliunn, ser\'e to distinguish it from the two genera. Besides, it differs from Halcampa in having sometimes more than 12 tentacles, but in this respect it agrees with Caftoso»H«. The presence of extra-tentacles indicates that there are weak mesenteries in the uppermost part of the coluum as in Halcampclla of the Halcampoididae. As Halianthus is a synonym of Halcampa I propose a new name for it Synhalcampa, characterized as follows: Halcampidae with no external differentiation of capituluni, scapus and physa. .\boral extremity provided with a porus. Column with 12 longitudinal rows of solid tubercles, towards the aboral end obsolete. Sphincter weak, close below the base of the tentacles. Tentacles 12 or some more, short, but stout and cyhndrical. Two rather well-developed siphonoglyphes and 2 pairs of direct- ives. Six pairs of perfect mesenteries with rather strong pennons. When the tentacles are more than 12, some very weak mesenteries are probably found in the uppermost part of the column. Excepting these, no imperfect mesenteries. 22 ACTINIARIA size of the animal, very strong, seems to indicate that we have to do with an Ilyanthid. In another paper I will give a more complete description of the genus than that given by Mc. Murrich. The new genus Parahalcampa from the Antarctic, of which I cannot give a full description here, I characterize as follows: Halcampidae with elongated body. Column not divisible into regions, without cuticle and "Halcam- papapillae". Proximal end physa-shaped, penetrated by apertures. The most distal part of the column with spirocysts. Sphincter as in Hal camp a. Tentacles lo, thick and short. A single weak siphonoglyphe. Number of mesenteries io + lo. The lo first (the "Edwardsia-mesenteries" + the fifth couple) perfect, fertile and with strong, longitudinal pennons and filaments. The lo others (the sixth couple + the dorsolateral and lateral mesenteries of the second order) imperfect, sterile, weak, without longitudinal pennons and filaments, in the whole length of the body. Type P. antarctica n. sp. Family Edicardsiidac. Diagnosis: Athenaria with elongated body, divisible into two or commonly into three regions, witliout sphincter or acontia. Tentacles always present. 8 perfect and fertile mesenteries. Two opposite pairs, the longitudinal muscles of each turning away from each other, forming the two directive pairs of mesenteries, and between these on each side 2 mesenteries with the longitudinal pennons turning towards the ventral directive. Four to several weak and very short mesenteries in the uppermost part of the column, always without filaments and reproductive organs. Ciliated streaks always present, sometimes discontinuous. Owing to the presence or absence of nemathybomes (Nesselhockerkapseln) and to the occurrence of two different types in the arrangement of the tentacles I have (1900) divided this family into two subfamilies, Edwardsiinae and Milne-edwardsiinae, corresponding to my families Edwardsiidae and Milne-edwardsiidae (1893) — a division which I will provisionally keep, though it is possibly a question, if it would not be more correct to place the Edwardsiinae together with Peachia, Haloclava and Eloactis in a family, and the Milne- edwardsiinae together with the family Halcampoididae (compare above p. 20). To the former subfamily the genera Edwardsia (inch Edwardsiella and Edwardsioides) and Isoedwardsia belong, to the latter Milne-edwardsia and Paraedwardsia. The generally very elongated body-wall is divisible into two or three regions, as it is often the case in the Athenaria.. The most distal part, capitulum, is always present, but comparatively short. It is de\-oid of a cuticle and provided with 8 longitudinal furrows, corresponding to the insertions of the mesenteries. These furrows are more or less distinct, the most conspicuous in the genus Milne-edwardsia, especially in M. carnea and still more in M. loveni, in which the capitulum has a decidedly polygonal appearance. The other part of the column is formed either wholly by the scapus, provided with a cuticle, or by a more or less deve- loped physa, commonly ampuUaceous and devoid of cuticle, added to the most aboral part of the column. The physa is the most distinct in the genus Edwardsia, while in the genera Milne-edwardsia and Para- edwardsia it is either lacking or not well-developed. In the genus Isoedwardsia there is never any physa, but the most aboral part shows the same structure as the scapus. Transverse sections through the most aboral AC1~INIARIA 23 part of the body-wall in Edwardsia therefore differ in appearance from those of Isoedwardsia. In Edwardsia we find in this region a thick ectoderm without cuticle (textfigs. 6, 62) and with scattered nematocysts; in Isoedwardsia commonly, (but not always) a thin ectoderm, always provided with cuticle, and the nemato- cysts enclosed in the nemathybomes (textfig. 69, compare below). The pliysa of the genus Edwardsia is probably always perforated by apertures. It is true that I have not examined all the specimens of Edwardsia, described here, in that respect, but as I have observed apertures in the physa of all the species [E. andresi, vegae, ardica, finmarchica, vitrea, longicornis), the aboral end of which I ha\'e thoroughly examined, it may not be precipitate to attribute such apertures to all Edwardsia-s^aciQS. To judge from the structure of the wall Fig. 6. Fig. 7. Fig. 8. Textfig. 6. Longitudinal section of the proximal part of the body of Edwardsia andresi ne: nemathybomes, me: mesentery. The ectoderm of the physa is partlj' lost. — Textfig. 7. Transverse section of the upper part of the actinopharynx with parts of the mesenteries of Edwardsia claparedii. — Textfig. 8. A similar .section in the lower part, si : siphonoglyphe. of the apertures of E. vegae it seems as if the apertures are invaginations of the ectoderm. The apertures are surrounded by a circular thickening, possibly of the ectoderm and forming a mo\-able stopping which is directed outwards (textfigs. 50, 51) or inwards (textfig. 62), according to the different state of contraction of the physa. The endodermal muscles form a circular sphincter round the. apertures. The other Rdwardsiidae are probably devoid of aperture in the proximal end; I will, however, remark that I ha\e not examined the proximal part of the column as thoroughly as in the genus Edivardsia. The scapus is provided with a weaker or stronger cuticle or periderm. In Isoedwardsia ingolfi and Milnc-edwardsia loveni I have found the strongest cuticle. In the genus Pflrae^iwarisja there are "Halcampa- papillae", which are wanting in the other genera. Concerrung the structure of these papillae I refer to the genus Halcampa. The nematocysts of the scapus-ectoderiu in the four genera show a different arrangement and are of a ver>' different size, in comparison with the nematocysts of the capitulum. In the simplest case the nematocysts of the scapus are scattered as in Paraedwardsia, now placed mainly on the ridges as in Milne- edwardsia loveni, now for the greater part collected in larger or smaller clusters as in Milne-edwardsia carnea, folaris and natlwrstii. Sometimes these clusters are arranged in shallow invaginations of the mesogloea as ACTINIARIA Fig. 9. Fig. 10. Textfigs. 9 — II. Arrangement of tentacles and mesenteries in Edivardsia andresi (fig. 9), E. claparedii (fig. 10) and Milne- edwardsia loveni and carnea (fig. 11). In order to show the arrangement in pairs, the imperfect mesenteries are drawn as having pennons. In fact that is not the case. in Milne-edwardsia polaris. These clusters form weak batteries of nematocysts. In the g^rnxsEdwardsia and Isoedwardsia the nematocysts of the scapus are more concentrated and enclosed in so-called nemathybo- mes, forming strong batteries of stinging capsules. The nemathybomes are now arranged in 8 longitudinal rows as in E. titberculata, claparedii and longicornis, now irregularly scattered as in E. vitrea, fmmarchica, sipunculoides, intermedia and others. Possibly there are more than 8 longitudinal rows in some species. The nemathybomes appear the most distinctly in the species with 8 rows. Here they are fewer in number, but commonly larger and form conspicuous tubercles on the scapus; on the other hand, if the nemathybomes are scattered they are smaller, but more numerous and projecting a little or not at all over the surface of the scapus, according as the con- traction of the animal is strong or weak. The nemathybomes form a capsule in the mesogloea and are filled with more or less numerous nematocysts and their mother-cells. The walls of the nemathybomes are formed by the mesogloea which is only perforated in the apex of the nemathybomes. Here the scapus- ectoderm is in connection with the nemathybomes, and through the aperture the nematocysts eject their ACTINIARIA 2<; stinging threads. The nemathybomes are to be conceived as stinging batteries invaginated in the mesogloea. Also the size of the scapus-nematocysts, in comparison with that of the nematocysts of the capitular ectoderm, seems to depend on, whether the nematocysts are arranged in nemathybomes or not. In the genera provided with nemathybomes, Edwardsia and Isoedwardsia, the nematocysts of the nemythybomes are narrow and long and commonly several times as long as the small nematocysts of the capitulum. In the sub-family, Milne- edwardsiinae, on the other hand, the nematocysts of the scapus are more short and broad and hardly larger than the nematocysts of the capitular ectoderm, which are generally considerably larger here than in the sub-family Edwardsiinae. Especially in Milne-edwardsia loveni and carnea there are numerous nematocysts on the capitular ridges (textfigs. 75, 79). The ectoderm of the column probably never contains any spirocysts, nor is it provided with longitudinal muscles ; sometimes there is a weU-developed nerve-layer in the ectoderm of the capitulum (in Edwardsia andresi and Paraedwardsia sarsii) . The mesogloea contains a few cells and are more or less tliickened; on the capitulum it forms the main part of the ridges, when any such appear (as in Milne-edwardsia loveni and M. carnea) . The endodermal, circular muscles are more or less developed, but never concentrated to a sphincter; they here and there break through the mesenteries, as always in theActi- niaria, and are thus in these places enclosed in the mesogloea. In Milne-edwardsia nathorstii and Paraedwardsia sarsii nematocysts occur in the endoderm. The tentacles are short, in sexually ripe individuals probably never less than 12. As I have already pointed out in a previous paper the tentacles are arranged in two different ways (compare Carlgren 1893; 1904). The first type, observed in different Edwardsia-s^Q.aQs and in Isoedwardsia mediterranean, and probably characteristic of these genera, we may call the Edwardsia-type (textfigs. 9, 10). It is characterized by its inner tentacles, off-shoots from the endocoels, being shorter than the outer tentacles, — an arrangement which we find again in some Halcampoididae, viz. in Peachia, Eloactis and Haloclava. On the other side, in the second type, the Milne-edwardsia-type (textfig. 11) the inner tentacles are longer than the outer ones, as it is commonly the case in the Actininae. Representatives of tliis type we meet in the genera Milne-edwardsia and Paraedwardsia. This type is probably characteristic of these genera, as I have found such an arrange- ment^ in all cases where I have been able to undertake a thorough examination of them. The ectoderm of the • Bourne (1916, Journ. Linn. Soc. 32 Zool. p. 513) has given an account of the order of succession of the niicro-mesen- teries and tentacles in the Edwardsiae. I think that in many respects his statements are erroneous. Edwardsia duodecimcirrata {E. Liitkenii) is no Edwardsia but a Halcampa duodecimcirrata (compare Carlgren 1893 p. 38). The parasitic larva of Halcampa, described by Haddon, is the larva of Peachia (Carlgren 1904. Zool, Anzeiger 27 p. 536). The arrangement of the tentacles and the mesenteries in E.claparedii is that typical of the Edwardsia with i6 tentacles (compare the scheme and Carlgren 1904 I.e. p. 543) and the grouping of the mesenteries evidently identical with that described by Bourne in E. beautempsii and willeyana. (Andres has confounded the dorsal and the ventral side in E.claparedii; in ray paper (1893a) I supposed that Andres's state- ment of the tentacular arrangement was correct). Unfortunately the order of succession of the tentacles in the Edwardsia is not known in details in any species, but we are obliged to construct it from different stages of different Edwardsia-species, a pro- ceeding which always leads to a more or less uncertain result. In doing this we are in the first instance to study the tentacles of live specimens and, if necessary, to supply oiu: observations with sections. As, however, the inner tentacles of the genus Ed- wardsia s. str. are (always?) shorter than the outer ones, as in Peachia, Eloactis and Haloclava, it is probable that the tentacles 9 — 12 are developed on a biradial plan (Carlgren 1904 1. c, a paper overlooked by Bourne), while in the genus Milne-edwardsia the tentacles are arranged after the number 6 with the inner tentacles longer than the outer ones and the first 12 tentacles prob- ably developing on a bilateral plan. (Carlgren 1S93 textfig. 3, 4. 1893 b, textfig., 1904 p. 534). That the tentacles of E.clapa- redii, M. loveni and carnea are arranged in such a manner as here stated by me (textfigs. 9 — 11) is a fact that I have controlled several times in living specimens and in sections. In living E. claparedii it is easily seen that the directive tentacles belong to the inner, shorter tentacles which are often bending towards the mouth. The parts of the oral disc lying over the directive chamb- The Ingolf-Expedltioii. V. 9. ,4 ■^ 26 ACTINIARIA tentacles contains nematocysts as well as spirocysts. The longitudinal muscles of the tentacles are always ectodermal as are also the radial muscles of the oral disc. The actinopharynx is longitudinally sulcated. In no'casel have observed any dorsal siphonoglyphe ; on the other hand, I have in representatives of all four genera found a ventral siphonoglyphe, a little developed. It it distinguishable from the other furrows of the actino- pharynx through its cells being provided with longer cilia than those of the other part of the actinopharynx (Textiig. 7, 8). The ectoderm of the actinopharynx contains nematocysts, sometimes of two kinds. The mesenteries are partly perfect, provided with reproductive organs, longitudinal pennons and filaments, partly imperfect without such organs, and only present in the uppermost part of the column. The former, "the Edwardsia-mesentenes" , are arranged as the diagnosis indicates. There are thus 2 pairs of direc- tive mesenteries and 2 couples of lateral mesenteries, the latter forming pairs with 4 imperfect mesenteries (textfig. 9). In the simplest case there are only 4 imperfect mesenteries developed, belonging to the first order, as in E. andresi (textfig. 9). In most species a more or less imperfect cycle of the second order is added, and sometimes one of the third order. The longitudinal muscles of the perfect mesenteries always form pennons with more or less numerous folds. The pennons are always distinctly distinguishable from the other part of the mesenteries, but seem never to be circumscript in the sense that the inner and outer lamellar parts of the mesenteries issue from one point of the fold or very close by each other. The outer lamellar part of the mesenteries is in the reproductive tract attached to the pennon near its outer edge or somewhat nearer to the middle of it. At the insertions of the mesenteries on the colunm the perfect mesenteries have developed the so-called parietal muscles ; one part of these is placed at the same side as the pennons and is only a differentiation of the longitudinal muscles, the second part, arranged at the opposite side of the mesenteries, is homologous with the parietobasilar muscles in the more differentiated Actiniaria (Carlgren 1905). The parietal muscles also show a different appearance in several species, com- monly extending, and as a rule without folding, over a smaller or greater part of the column, whereby the contraction of the body in longitudinal direction is facilitated. In exceptional cases, as in Milne-edwardsia nathorstii, these column-muscles are comparatively strong and form rather high folds (textfig. 85) . Towards the aboral end of the body the longitudinal pennons taper more and more and end by fusing with the outer ers are namely of another colour than the other part of the disc. Bourne supposes that the development of the micro-mesen- teries in the Edwardsids is another than in the other Actiniaria and will not regard the mesenteries 9 — 12 and the other micro- mesenteries as homologous with those on the Actiniaria. In comparing the mesenteries as homologous with those of for instance Halcampa (Carlgren 1893 a textfig. 0. i a) I cannot find any difference. The arrangement of the mesenteries in E. claparedii and in other Edwardsia having 16 tentacles agrees for instance with that in Gonaciinia and in a young specimen of Sagartia (Cy- lisla) undata (Carlgren 1893 a p. 99). Bourne's statement that the micro-mesenteries in Edwardsia arise in couples of singles, and not in couples of pairs as in the Actiniaria, certainly needs a more extensive examination before it can be accepted. I think that the development of the tentacles is mainly the same in the Edwardsids and in the other Actininae. As namely, by the appearance of a new pair of mesenteries in the Actiniaria, the new tentacles, one endocoel- and one exocoel-tentacle, do not arise quite simultaneously, and as the foundation of the mesenteries agrees with that of the tentacles, it is clear that in certain stages of development we miist iind single mesenteries instead of pairs. (Compare Bourne's statement Quart. Journ. Mic. Sc. 63 1919) concerning the development of the mesenteries of Phellia. Also in the paper by Faurot (1905) in which he describes the devel- opment of the tentacles of Ilyanthus, we can in some figures see an indication of a different size of both mesenteries of the same pair (that this is not always the case is probably an inadvertency of Faurot, to whom the principal object has evidently been to investigate the order of appearance of the tentacles and not that of the mesenteries). Besides this, it ought to be remarked that in several Actiniaria (in the Actinostolids, in some Halcuriidae as in Actinerniis and others) a great difference in both mesenteries, belonging to a pair, exists. Thus Bourne's suggestion that the Edwardsiae should form a special group of the Anthozoa, different from the Actiniaria, is, according to me, not well founded. ACTINARIA 27 part of -the mesenteries viz. with the parietal muscles. Thus the mesenteries are provided with a continuous, longitudinal muscle layer at the aboral end of the body. The ciHated streaks are always present. The state- ment of Andres (1880) that they are lacking in Edwardsia claparedii, I cannot confirm, as they were present in the specimens I have examined. In Isocdwardsia, at least certainly in /. mcditerranea, the ciliated streaks are discontinuous viz. scattered in several portions along the middle streak. A similar arrangement we find in Limnadinia laevis, Scyioplwrus antarcticus and Parahalcatnpa antarctica. As far as up till now is known, all Edwardsiids are dioecious. Only the 8 "£'(^ie'«y(^s/«-mesenteries" are provided with filaments and repro- ductive organs. A classification of the Edwardsiidae, especially of the species of the genus Edwardsia, is rather difficult. The different size of the nematocysts however forms quite a good character, and so do also, though in a smaller degree, the structure of the muscle pennons and that of the parietal muscles. In order to get good points of comparison the sections of the muscle pennons and the parietal muscles have been taken, when possible, in the upper part of the reproductive region. Sections through different tracts of the body are namely of a very different appearance in the same species. In order to decide whether the structure of the pennons and the parietal muscles is practicable as a valuable species-character I have often reproduced figures of both kinds, belonging to species from different localities. Sub-family Edwardsiinae. Diagnosis. Edwardsiidae with the physa well-developed or wanting. Scapus provided with nema- thybomes. Nematocysts of the capitulum, in comparison with those of the nemathybomes, small. Inner tentacles, endocoel-tentacles, shorter than the outer ones. The genera Edwardsia Quatr. and Isocdwardsia Carlgr. belong to this subfamily. Genus Edwardsia Quatref. Diagnosis. Edwardsiidae with body-wall divisible into three regions; physa, scapus and capitulum. Physa always present, without nemathybomes. Scapus with a more or less developed periderm (cuticle) with nemathybomes containing nematocysts in a rounded cavity in the mesogloea. Nematocysts in the nema- thybomes long, in proportion to the breadth. Nemathybomes in 8 longitudinal lines, or more or less irregularly scattered, now distinctly conspicuous upon the scapus-surface, now on a level with it. Nematocysts in the ectoderm of the cuticle-lacking capitulum small. Tentacles 12 — 16 or in several cycles, the inner shorter than the outer (always?). Actinopharynx with a single, feebly developed, ventral siphonoglyphe (always?). To the genus Edwardsia I have here referred the genera Edwardsia, Edwardsiella and Edwardsioides. The establishment of the last genus is not justified, because, according to my examination of the type-specimen, it is not different from a typical Edwardsia [Edwardsiella] . On the other hand it it questionable, if the genus Edwardsiella ought to be maintained. The genus is proposed by Andres (1883) for the Edwardsiidae having more than 16 tentacles. Concerning the number of the tentacles I tliink that it is of no great importance as 4' 28 ACTINARIA a genus-character, be- cause the number varies very much in several species. The arrange- ment of the nemathy- bomes, on the other hand, may — as before pointed out by me (1898, 1900) — be used with more success for the di- stinction of both genera ; in the genus Edwardsia the nemathybomes are arranged in 8 longitudi- nal rows, in Edwardsiella they are more scattered. As it is on several occa- sions very difficult to determine the arrange- ment of the nemathy- bomes in preserved and often strongly contracted material, a strong con- traction causing several displacements in their re- lative position, it is, how- ever, for practical rea- sons and in order to avoid confusion, the most reasonable to place to- gether Edwardsia and Edwardsiella in a single genus Edwardsia. I give below a sy- nopsis of the Arctic and Northern Edwardsia-spe- cies, examined by my- self. a u- 'Z y 9 B 0 ». ft « n> •< 3 O ri — 5 3 3 5L " 3 W 3 a. i< ° i 3- n *. to 0 X ^ X X 1 X 1 0 CO 1 X y 1 1 Xi p I X f rr X I I X X ■«»■ ^ X X I * "S X X "\ o t if o 3 3 O en 0(9 a S3 en en •T3 fD O t— • rt> 09 a «> en ft 1-1 i^» » a ACTINIARIA 29 Edwardsia tuberculata Diib. and Koren. PI. I. Kig. 20. Edwardsia tuberculata u. sp. Diiben and Koren 1847 P- 267. — — Diib. & Kor., Koren 1857 p. 93. Sars 1861 p. 262. O. & R. Hertwig 1879 PI. i. figs. 2, 6. — clavata Rathke p.p. Andres 1883 p. 308. Carlgren 1893 a p. 12. Appellof 1895 p. 7. 11 Grieg 1897 p. 12. — ? — Rathke. Appellof 1891 p. 12 figs. 10 — 11. Diagnosis. Physa well-developed. Scapus with a rather well-developed periderm and 8 distinct lines of large, rather few nemathybomes. Nematoc}^sts of the nemathybomes partly 60 — 96 X 2.5 //, partly (72) no — 190 X (4) 5 — 7 n- Nematocysts of the capitulum 11 — 13 X 1.5 /i- Tentacles 16. Neinatocysts of the tentacles 18 — 26 X about 1.5 [i, their spirocj^sts 14 — 22 X 2.5 /y. Nematocysts of the actinopharynx partly typical 22 — \^y X 2.5 /i, partly with discernible basal part to the spiral thread 27 — 34 X 5 — 6//. Longitudinal muscle-pennons strong, in transverse sections elongated, in the upper part of the reproductive region with about 30 lower and higher, sparse, often dichotomously ramificated folds. Outer folds, in propor- tion to the inner ones, only slightly branched. Outer lamellar part of the mesenteries in the reproduc- tive region attached to the pennon rather close to the centre. Parietal muscles strong, with numerous folds (15 — 20 or more on each side), high, rather perpendicularly issuing and a little branched. The extension of the parietal muscles on the column very inconsiderable. Colour. Scapus commonly brown. Dimensions in strongly contracted state with the physa involved unto about 2 cm long and 0.7 cm broad. Occurrence: Norway. Bergen (Koren, Appellof) Bergen, Manger 15 fms. (Sars) Bergen Herlo fiord 6 — 12 fms. (teste Appellof) , Molde (teste Sars), Utne fiord 100 fms. (Bowallius 1882), Vaags fiord, Skavo-Tomberviken 40 — 80 fms. (teste Grieg), Halnaesviken (teste Grieg), Drontheim fiord Rodberg 150 — 200 m (Ostergren 1891) Norway without distinct locahty (I^iitken). Sweden. Koster fiord N. Hellso 100 — 150 fms. (C. Auriwillius 1895), Sneholmen (C. Auriwillius 1895), Vaderoame 60 — 80 fms. (1911). Denmark. Cattegat (Petersen). S. of Iceland 63°i5' N. 22=23' W. 326—216 m (Thor-Exp. St. 161). Exterior aspect; The physa is well-developed, but commonly involved. The scapus is provided with a rather strong cuticle. The large but few nemathybomes are arranged in 8 distinct, longitudinal lines and appear ver>- distinctly as papilhform off-shoots on the scapus. The scapus, as well as the capitulum, are polygonal, at least in the contracted state of the animal. The tentacles are 16, cylindrical, in contracted state rather thick. The actinopharynx is longitudinally sulcated. Anatomical description: This species has before been anatomically examined by O. and R. 30 ACTINIARIA Hertwig (1879) ^^^ ^y Appellof (1891), but in several respects imperfectly. Neither is my description as perfect as desirable, the material not always having been well preserved. The ectoderm of the scapus is considerably tliinner than the mesogloea. The nematocysts of the nemathybomes are numerous and of two kinds, both long, but one much more thin than the other. The longer and broader ones are a little thicker at the basal end, gradually tapering towards the distal end. In these latter the basal part to the spiral thread is commonly discernible. The size of the nematocysts (n) and the spirocysts (sp.) in the different parts of the body is seen on the following table. Habitat physa n. nemathybomes tentacles sp. capitulum actiuopharynx n(a) n(b) i) Bergen Manger 2) Bergen (Koren) 3) Vaderoarne 4) Kosterfiord N. Hellso . 5) — Sneholmen 6) St. 161 (Thor) 7) Norway (Liitken) 8) — — 9) Drontheimfiord 11-13 u 12-14 '< 1-5 12-16 X 1.5 74-96x2.5 a 72-S4X2.5 79-96x2.5 77-84x2.5 70-77 X 2.5 70x2.5 60-72 X2(2 5) 60-70 X 2 72-84 X 2 110-190x6-7 fl 122-144X 6 113-154X5-6 130-180x5-6 (108) 127-146x5-6 115-130x6-7 96-134x6 72-1 10x4-5 (86) 103-137x6-6 19-26 X 1.5^ 22-26 X 1.5 22-26x1.5 18-24x1.5 14-20 fl 17-22 X2.5 17-23x2.5 -22 X 1.5 ii-i3Xi.5^< ii-i3^t II-12 X I 29-34x2.5^1 29-36x2.5 29-37x2.5 22-29 29-34x5-6^' n(a) typical nematocysts, n(b) nematocysts with a conspicuous basal part to the spiral thread. As we see, the size of the stinging capsules agrees in the different specimens. Only in the specimens 7 and 8 the nematocysts of the nemathybomes are shorter; these specimens were also about half as long (length I.I cm, breadth 0.3 cm) as the others. Also in the smaller specimens the larger nematocysts of the nema- thybomes reach a length of more than 100 fi (compare Edw. longiconiis). Whether the n(b) -capsules, which are broader in the basal end, are constant, I cannot decide, I have not observed any in the specimens i and 2. In the maceration preparations of the two "Thor"-specimens, the ectoderm of which was very badly preserved, I found only one smaller nematocyst and 8 larger in the fragments of the nemathybomes. There is, however, no doubt that these specimens are E. tnherciilata, as the muscles of the mesenteries agree with those of the specimens from Norway. The 8 "Edwardsia-mesenteries" have strong pennons. O. and R. Hertwig (1879) have given a reproduction of a mesentery in the reproductive region. Owing to the comparatively few muscle-folds of the pennon the mesentery has probably been sectioned in the lower part of this tract, or the section possibly belongs to a smaller specimen. The textfigure 12 shows a section of a pennon in the upper part of the repro- ductive region. The pennon is rather elongated, the highest folds as usual next to the outside. The about 30 folds are mostly high, the high folds often dichotomously branched. The most ramificated fold is as usual the outermost. The parietal muscles are very high, the folds for the greater part dichotomously. branched and issuing almost perpendicularly from the thick, main lamella (textfig. 14). For comparison I have here also reproduced figures of a pennon (textfig. 13) and of a parietal muscle (textfig. 15), belonging to a young, not sexually ripe specimen. The folds of the muscles are here considerably fewer. The extension of the parietal muscles on the column is inconsiderable. ACTINIARIA 31 Fig. 12. Remark. Andres (1883) and after him I myself (1893) have placed this species together with Rathke's E. clavata, on the suppo- sition that the nemathybomes had been overlooked by Rathke. After having examined the Diiben and Koren's species I think that it can- not be identical with E. clavaia, be- cause the nemathybomes in E. tuber- culata are too large to be overlooked. In fact it is impossible to identify with certainty Edwardsia clavata with any here described species, as Rath- ke's description may be applied to several Scandinavian species. As no type-specimen oiE. clavata is known, I think that E. clavata may be dropped. I have not had the oppor- tunity to see the specimens from Molde nor those collected by Appel- lof and by Grieg; probably most of these belong to E. tubercnlata, at any rate the specimen reproduced by Appell6f(i89i) indubitably belongs to this species. On the other hand it is questionable if the specimens, dredged in the Herlofiord from shal- low water (6—12 fathoms) really, are this species, as E.iiiherculata seems to live in deeper water (compare the occurrence). Fig- 13- • Textfigs. 12 — 15. Edwardsia tubercnlata. Transverse sections of pennons (figs. 12, 13) and parietal muscles (figs. 14, 15) in the re- productive tract. Fig. 12 spec, from the muse- um of Christiania, fig. 14 spec, from the Catte- gat (Petersen) and figs. 13. 15 young spec, from Utne fiord. Fig. 15- Edwardsia longicornis (n. sp.). Edwardsia clavata var. longicornis n. var. Carlgren. 1893 a p. 12. Diagnosis. Physa distinct. Scapus with a well-developed periderm and 8 lines of rather large but comparatively few nemathybomes. Nematocysts of the nemathybomes partly 36—65 X 2 (2.5 a partly 36—86 X 3.5—4-5 (5) /'- Tentacles 16, very seldom 12?. Nematocysts of the tentacles 17—23 X 2 (2.5) fi, their spirocysts 14—17 n long. Nematocysts of the actinopharynx partly typical, 14—17 X 2 /i and 25—29 X 2.5—3 [i, partly with discernible basal part to the spiral thread, broader in the basal end 26—30 X 7 [i. 32 ACTINIARIA im® longitudinal muscle-pennons rather strong, in the upper part of the reproductive region with about 13 — 18 folds. Outer part of the pennons stronger than the inner one. The outer lamellar part of the mesenteries attached to the pennon rather close to the centre. Parietal muscle in the reproductive tract with few to rather numerous, thin and a little dichotomously branched folds, issuing from a rather thin, main lamella of the ® II mesogloea. The extension of the parietal muscles on the column ordinary. Colour. Physa unco- loured. Scapus ochreous-y el- low to orange or more dirtily- grey. Nemathybomes unco- Fia. 16. b mil nil loured. Capitulum now un- coloured, now paler or dar- ker brownish-red, in the latter case with opaque white /"" . " spots, with conspicuous in- Textfigs. 16-18. Arrangement of the ne- ggrtions of the mesenteries. . Arrangement of the ne- mathybomes between two perfect mesen- teries in Edwardsia longicornis (fig. i6a) The spots are arranged in in E. pallida (fig. i66), in E. danica (fig. 17) and E.andresi (fig. i8). pm: parietal muscles. The figs. 16 and 18 are drawn confluent, forming indistinct, in the same magnification, the fig. 17 is more magnified than the others. £-.;oKgi- i" the Upper part broader, cornis and pallida (from Bohuslan) and longitudinal Unes, often ter E. andresi (from Lyngen) were well ex- panded, E.danica (from htile Baelt, Mor- minating below the tentacles ten sen) was more contracted. The ecto- .,, 111/^1 . ' . ,. , . With a more clearly denned derm m the preparations has been pen- cilled away. Fig. li the middle-hne and often Fig. 17. part. Tentacles uncoloured, with scattered, irregular, yellowish-white and reddish-brown spots. Oral disc yellowish-wliite shading off into ochre, with smaller white and larger brown spots and stripes. Dimensions in extended state: unto about 3 cm long and 0.3 cm broad. Occurrence: Norway. Drobak (Ivittken). Sweden. Bohuslan. Stromstad fiord (1882), Koster, Styrso 10 fms. (Carlgren 1889), Bolthalan 20 — 25 fhs. (Hansson), Vaderoarne 8 — 10 fms. (Carlgren, Ostergren and others) very common, 15 fms. (Goes 1882), Varholmen (Carlgren), Gullmar fiord, Samstad 8 — 10 fms. (Carlgren 1889) common, Zool. Stat. Kristineberg (1893), Gaso "ranna" 8 — 10 fms. (Carlgren 1889 ■ — 90), N. Gaso fiord (Wiren 1890). Bohuslan without distinct locality (I/O V en). Gothenburg Styrso (I^agerberg). ACTINIARIA 33 9. Edwardsia longicornis Transverse section of a portio the scapus between two mesente- ries with a neniathybonie (hc). Denmark. Samsobelt (Winther), Cattegat without distinct locality (Petersen). The Sound S. of Hven 9 fms. (Gunhild Exp. 1878 st. 33), S. of Hven 17— 26 ni; W.N.W. of Wiken ("Sven Nilsson" st. 30, 52 c). Exterior aspect. The physa is well-developed, the scapus provided with a thin periderm, with which is combined a rather thick and soft layer, comiiKMily ochre-coloured and pro1)ably, at least partly, formed by closely-packed mucus-particles. The comparatively few, but rather large nenia- thybomes are arranged in S longitudinal hnes as in E. tuberctdata (textfigs. 16 a, 19), quite another distribution than in E. pallida (text- fig. 16 b). The nemathybomes are generally distinct, only if the animals are very con- tracted or the periderm is loosened from the ectoderm, it is sometimes difficult to discern them. Also in contracted specimens the nemathybomes keep in the main the same position, though they are often a little displaced and approached to each other. The upper part of the column at stronger contraction shows a polygonal appearance which is more distinct in extended specimens. The tentacles are almost always 16, arranged in 2 cycles as in E. clafaredii (compare textfig. 10); in a very small (0.4 X 0.15 cm), but fertile specimen from Samso belt, sectioned by myself, I have not found more than 12 tentacles. Thus it looks as if the species could be ripe already in a stadium with 12 tentacles and with more than normally weak mesenterial muscles (compare below) \ at least in the Danish seas, where the genus moreover does not reach the same size as in Bohuslan. Perhaps we here meet with the same case as in Halcampa duodecimcirrata which is ripe in a stadium with onlj- 8 perfect mesenteries and 10 tentacles (Carlgren 1893 a), at least at our coast, where it is smaller than at the coast of Norway. The tentacles are conical and, in comparison with those of E. pallida, long (the name longicornis, however, does not indicate that the tentacles are longer than in the Edwardsia-s^Qci&s in common), the inner endocoel- tentacles are about two thirds as long as the outer exocoel-tentacles. The oral disc is conical and pro\-ided with radial furrows corresponding to the insertions of the mesenteries. The actinopharynx as usual is furnished with 8 longitudinal furrows, the ventral one of which forming a weak siphonoglyphe. Anatomical description. The nematocj'sts of the nemathybomes are of two kinds, one shorter and thinner and of almost equal breadth, the other longer and broader and of different breadth at the basal and at the distal end, the latter the narrower. The size of the nematocysts and the spirocysts in the different parts of the body appears from the following table (see page 34). The 8 "Edwardsia-nxGS&nt&n^s" are provided with well-developed, in transverse sections not elong- ated, longitudinal pennons. The highest folds appear as usual at the outside of the pennons, in the innermost l^art there is often also one high fold. The number of the folds in the upper part of the reproductive region ' It may be possible that we have to do with a distinct species here, but ray material is too poor for deciding it. The parietal musdes of the Samso specimen recall those of E. danica. The Ingolf-Expedilion. V. 9. 34 ACTINIARIA Habitat nemathybomes capitu- lum tentacles n. sp. actinopharynx n (a) n (a) n (b) i) Vaderoame 2) Kristlneberg 3) Styrso 4) Varholmen 5) Drobalc 6) Bohuslan Zool. St. 7) Kattegat 8) - 9) Samso Belt 58-62 X 2.5 fl 53-65 41-58 X 2.5 43-61 X 2 41-48 X 2 48 X 2 36-50 X 2 about 46 X 2 43-55 X 2 4S-81 X 4-511 48-86 41-72 X 4-5 46-67 X 3.5 (-5) 41-58 X 4 (5) 48-65 X 3.5-4-5 36-61 X 3.5-4 38-53 X 3.5-4 43-65 X 3.5 (5) 19-23 X 2fl 17-22 X 2(2.5) 14-17," 14-17 14 X 2 11 14-17 X 2 25-29 X 2.5-3,i( 30 X 7," 26 X 7 11, n(a); typical nematocysts, spirocysts, n{b): nematocysts with discernible basal part to the spiral thread. The specimens provided with smaller nematocysts were small No. 8 (0.55X015 cm No. 9) 0.65X015 cm. never exceeds 20; they variate in number; in several sectioned specimens I have found between 13 to 18 folds. I have reproduced the pennons from 3 different specimens in the textfigs. 20 — 22, of which textfig. 22 Fig. 20. Fig. 21. Textfigs. 20 — 24. Edwardsia longicornis. Transverse sections of pennons (figs. 20 — 22) and parietal muscles (figs. 23, 24) in the reproductive tract. Figs. 20, 21, 23 specimens from Bohuslan. Figs. 22, 24 specimen from Saniso Belt, compare the text! Fig. 22, Fig. 23. Fig. 24. ^^m^^rn^ ACTINIARIA 35 is taken from the sexually ripe Samso-specimen with 12 tentacles. Though the number of folds variates in the different specimens the folds agree in appearance. The outer lamellar part of the mesenteries is attached to the pennon rather close to the centre. The weak, imperfect mesenteries in the uppermost part of the column are comparatively weU-developed. The mesogloea off-shoots, supporting the parietal muscles, are often dichotomously branched and delicate, like the main lamella of the mesogloea. The folds of the parietal muscles var>- considerably in number, as shown by the textfigures 24 of the Samso-specimen and by a speci- men from Bohuslan (textfig. 23) (compare note p. 33). In larger specimens the parietal muscles appear similar to those of the textfigure 23. The expansion of the parietal muscles on the column is the ordinary one. Remarks. This species is nearly alhed to E. tuherculata, but is distinguished from this species by a more delicate form, by fewer folds of the muscles in the pennons, and above everything by smaller nemato- cysts of the nemathybomes. To this we might object that this difference in structure is due to a difference in age. As, however, the smallest specimens examined of E. luberculata are smaller than the larger of E. longi- cornis, and as nevertheless the nematocysts of the two specimens differ very much in size, I must regard them as two different species. Besides this, E. longicornis seems to hve in more shallow water than E. tuherculata which prefers deeper water. I have never found E. longicornis to reach the dimension of E. tuherculata, and yet I have a great material of the former for examination. Edwardsia pallida (n. sp.). Edwardsia clavata var. pallida n. var. Carlgren 1893 p. 12, 14 Pi. 2 figs. 5 — 9. Diagnosis. Physa well-developed. Scapus with a thin periderm with irregular aggregates of nema- thybomes. Nemathybomes in the aggregates mostly very closely packed. Nematocysts of the nemathybomes partly 36 — 53 X 2.5 ^, partly 62 — 74 X 5 u, the latter often curved. Tentacles 16, now ver>' short, cyhndrical, not pointed, now longer and more conical. Nematocysts of the tentacles 17 — 19 X 1.5 — (2) fji, their spiro- cysts II — 14 X I — 1.5 (2)//. Nematocysts of the actinopharynx partlj- 22 — 26 X 1.5 — 2/1, partly 29—36 X 2.$ iJi. Longitudinal muscle-pennons rather strong, in the upper part of the reproductive region in trans- verse sections elongated with at most 20 (about 14 — 17) folds. Outer and inner part of the pennons com- paratively richly branched with high folds, the middle part with simple or only shghtly branched, short folds. The outer lamellar part of the mesenteries attached to the pennon not far from the outside. Parietal muscles in the reproductive region rather strong, with folds somewhat closely arranged, rather high and a little ramificated. Mesogloea in the parietal muscle-tract thickish. The expansion of the parietal muscles on the column is the ordinary one. Colour. Physa uncoloured. Scapus mostly dirty-grey, sometimes ochreous-yellow, especially in the upper part. Capitulum uncoloured, transparent, its upper part sometimes j'ellowy-white with indistinct white hues on each side of the mesenterial insertions. Close to the tentacles a reddish-brown area is sometimes found, but it only seldom forms a continuous annulus as it is interrupted by the white Unes. Tentacles un- coloured, transparent, with a brown streak at the base, at the inside of their apex a more or less distinct 5* 36 ACTINIARIA 4 wliite spot and often another one at the base of the tentacles. Oral disc yellowy-white, with brown streaks nrnmifl the mouth. Dimensions in very extended state to about 6 cm. long, commonly shorter, breadth 0.3 — 0.4 cm. Occurrence. Sweden. Bohuslan, Vaderoarne 8 — 10 fms., sand (Carlgren, Oestergren) together with E. longicornis, but less frequent than tliis species. — 60 fms. (Gunhild-Exp. 1878). Exterior aspect. The physa is well-developed. The scapus is provided with a thin, sUghtly adherent periderm, commonly of a dirty-grey colour. The in- sertions of the mesenteries are conspicuous, apparently neither the scapus nor the capitulum are polygonal, at least not in extended state. The nemathybomes are not visible to the naked eye, wherefore the scapus seems to be devoid of them. They do, however, ap- pear in great numbers and are mostly irregularly packed together in groups (textfigs. i6b, 25, 26, com- pare the anatomical description). The tentacles are 16 in number, now very short, cylindrical, not pointed, now conical and longer. The arrangement of the tentacles in two cycles is not as distinct here as in other Edwardsia-s^eciQS, at any rate not when the tentacles are short. The oral disc and the actino- pharynx are of usual appearance, the latter provided with 8 longitudinal furrows of which the ventral one is the broader and forms a weak siphonoglyphe. Anatomical description. The nemathybomes Fig. 27. Textfigs. 25 — 27. Transverse sections of the scapus between two mesenteries of Edivardsia pallida (figs. 25, 26) and Edward- sia danica (fig. 27). ne: nemathybomes. Fig. 25 is drawn from an expanded specimen, fig. 26 from a contracted, fig. 27 from a ^f |-]jg gcapus are comparatively Small and usually col- rather much contracted specimen. lected in irregular groups; here and there a single nemathybome appears. In the aggregates the nemathybomes are \'ery closely packed, separated from each other by a thin mesogloea-lamella. They therefore get an appearance as if they were composed of several nemathybome-capsules (textfigs. 25, 26 — Carlgren 1893 PI. 2 fig.9; in the reproduced figure in my paper 1893 it seems as if a single nemathybome is situated right opposite to the parietal muscle; the cavity is, however, an artiiicial product caused by the loosening of the ectoderm from the mesogloea.) Also in other Erfwardlsja-species with scattered, not regularly arranged nemathybomes, for instance in E. vitrea, andresi, danica, the nemathybomes may in transverse sections get an appearance recalling that of the nemathybo- mes in E. pallida, especially if the animals are contracted, in which case the nemathybomes are of course more close than when the scapus is extended. In no other species I have, however, observed nemathybomes as strongly agglomerated as in E. pallida. That the nemathybomes are in reality very close we may con- clude from the textfigures 25 and 16 b, the latter of which represents a piece of a compartment with the ACTINIARIA Z7 nemathybomes, seen from the surface, in a very extended specimen. In contracted animals the nema- thybomes are still more closely packed (textfig. 26). The nematocysts of the nemathybomes are of two sizes, partly 36 — 53 x 2.5 /i, partly 62 — 74 X 5/^, the latter are often a little curved; one part of the nematocysts appears granulated. The nematocysts of the tentacles are 17 — 19 X 1.5 to almost z ji, their spirocysts 11 — 14 X i- — 1.*5 (2) {i. The nematocysts of the actinopharynx are partly 22 — 26 X 1.5 — 2 /i, partly 29 — 36 x 2.5 //. The siphonoglyphe is provided with longer cilia than the other part of the actinopharynx. The 8 "frfzefarrfsia-mesenteries" are well-developed, the other 8 mesenteries in the uppermost part of the column are also distinct. I have before described and reproduced the former (Carlgren 1893 PI. 2 figs. 5 — 8) from different parts of the body. The longitudinal muscle-pennons are in trans- verse-sections somewhat elongated and show, at most, about 20, commonly 14 — 17 folds. They are especially high in the outer and also in the inner part and rather richly ramificated; between these folds there are shorter ones, simple or a little branched (textfig. 28 transverse-section through the upper part of the cnido-glandular tract). The outer lamellar part of the mesenteries is at- tached to the pennon rather close to the outside. The parietal muscles of the same tract show rather numerous folds, a little branched and attached to thickish off-shoots of the mesogloea, the main lamella of the mesogloea is likewise in the outer part thick (textfig. 29). The expansion of the parietal muscles on the column is the ordinary one. Remarks. I have before (1893) described this species as a variety of E. clavata. A closer examina- tion, particularly of the distribution of the nemathybomes, however, proves that it is well differentiated from the species, called by myself E. clavata var. longicornis = E. longicornis, though they were both of them dredged in the same locality (compare E. iuberculata, longicornis and danica). Fig. 28. Textfigs. 28 — 2g. Edwardsia pallida. Compare the text! Edwardsia danica n. sp. Dimensions. Physa well-developed. Scapus with a rather well-developed periderm. Nemathy- bomes from somewhat small to small, scattered, but not closely packed together in groups. Nematocysts of the nemathybomes partly 24 — 42 X (2.5) 3 — 3.5 (4) 11, partly 46 — 72 X 4 — 5 //, the latter sometimes very sparse (or absent?). Tentacles in varying numbers unto 20 of ordinary length. Nematocysts of the tentacles 17 — 19 X I — 2 /i, their spirocysts 10 — 17 X i^ — 2 ;/. Nematocysts of the actinopharynx partly 15 — 19 X o ACTINIARIA I 2 11, partly 24 — 34 X 2 — 2.5 /i. lyongitudinal muscle-pennons rather strong with folds of ordinary height and a little branched, in numbers less than 20, the stronger folds in the outer part, shortened inwards, and in the innermost part one or two longer folds. Outer lamellar part of the mesenteries attached to the pennon rather close by the centre. Parietal muscles comparatively weak, dichotomously branched. Expan- sion of the parietal muscles on the column considerable. Colour. Scapus dirty-grey to ochreous-coloured. Diinensions. In extended state the largest specimen with 20 tentacles (from Little Belt) was 2.4 cm high and 0.2 cm broad. The largest, a little contracted, specimen was 2 cm long and 0.25 cm broad. Occurrence. Cattegat (Petersen), Torboskar-Skagen 19 — 22 fms. (Gunhild-Exp. 1878), Little Middelgrund 10 fms. (Gunhild-Exp. 1878), Laholm bay 10 — 12 fms. (Gunhild-Exp. 1878), Great Belt Winther), Little Belt (Mortensen 1900), 7 — 24 fms. (Schiodte), off Lyngs Odde 10 fms. (Mortensen 1912), Samso Belt (Winther). The Sound (Moller, Liitken). Between Landskrona and Haken 17 — 21 m S. of Hven 17 — 26 ni; W. of Knahaken 23-25 m, W. of "Disken" 24 m ("Sven Nilsson" St. 27, 30, 42, 43 a, 52c), S. of Hven 6 — 24 fhs. (Gunhild-Exp. 1878). Exterior aspect. The physa is of usual appearance. The scapus is provided with a rather well- developed periderm. The nemathybomes are small, not visible to the naked eye and not protuberated on the surface of the scapus. They are scattered, not as numerous and not as aggregate as in E. pallida, which becomes evident by a comparison of the figs. 16 b, 17, p. 32. In surface preparations (textfig. 17) as well as in sections (textfig. 27) they show a different agroup- ment. Sometimes two nemathybomes close by each other are seen in contracted specimens of E. danica (textfig. 27) ; in shape they are, however, different from those of E. pallida. In order to control the arrangement of the nemathybomes I have sectioned several specimens of both species, examined them in surface prepa- rations and always found thorough differences in the agroupment of the nemathybomes. The tentacles are of usual size and appearance. They vary considerably in number. In the smallest, extended specimen from Little Belt (Mortensen 1912) there were only 12 tentacles (this specimen is, however, probably not fertile; I have sectioned the lower part of it, but not found any reproductive organs) ; in 3 other sectioned fertile speci- mens (from Samso Belt, Little Belt and the Sound St. 27) the number of tentacles was 14, 16 and 16. The best, extended specimen (from Little Belt Mortensen 1912) with evolved tentacles had 20 tentacles. In Edwardsia pallida I have observed only 16 tentacles. The oral disc and the actinopharynx are of usual appear- ance. A weak, ventral siphonoglyphe is present. Anatomical description. The periderm of the scapus is rather well-developed, in the paler specimens thinner. The nemathybomes are small and contain nematocysts of two different sizes, both a little broader at the basal end. The large capsules were mostly very sparse, in some specimens I did not find any in the maceration preparations; it is, however, possible that they are present also there. In the macera- tion preparations of the specimens 4 and 5 (compare the table) I observed only some few capsules. They always show a discernable basal part to the spiral thread what is also often the case with the smaller nema- ACTINIARIA 39 tocysts. The nematocysts of the actinopharj'nx are also of two sizes. The size of the spirocysts (sp.) and nematocysts (n) in the diverse regions of the body is as follows. Habitat nemathybomes capitulum n. tentacles n. .sp. actinopharynx Little Belt (Mo rt. 1900) — ( — 1912) — (Schiodte) . The Sound (St. 27) — (St. 42) — (St. 43 a) ... . — (St. 30) (Liitken) 29-39 X 3-5-4 ft 24-33 X (2.5) 3* 26-43 X (2.5 3-3.5 29-41 X 3-5-4 24-41 X 3 32-43 X 3 29-43 X 3-3.5 26-41 X 3-3.5 31-43 X 3-3.5 55-72 X 5 u 55-65 X 5 46-55 X 5 48-65 X 4.5-5 53-72 X 4-5 7-12 X 1.5 « 17-19 X 1-2 jU 17-19 X 2 17-19 X 2 14-18 X 1.5-2 10-14 X 1-2 fl 10-17 X 1-2 10-14 X 1-1.5 10-14 X 1.5 17-19 X 1.5- 15-19 X 1.5- 24 X 2-2.5 ," 29-34 X 2.5 26-31 X 2-2.5 Measured on sections. The 8 " Edwardsia-mesenteries" have well-developed, longitudinal pennons. The folds are rather high, but not as branched as in E. pallida (textfigs. 30, 31). The most ramificated folds are situated in the outer part, but also in the innermost part there are one or two such folds. The middle part of the pennon is more weak. The number of the folds is about the same as in E. pallida. The outer lamellar part of the mesenteries is attached to the pennon at some distance from its outside, in the repro- duced pennon (fig. 30) a Uttle nearer to the centre. The parietal muscles are com- paratively weak, and more or less dichotomously branched \ (textfig. 32), they are, how- ever, sometimes a httle stronger than the reprodu- Fig. 32. Textfigs. 30-32. Edwardsia danica. Transverse sections of pennons (figs. 30,31) and parietal muscle (fig. 32) in the upper part of the reproduc- tive tract. Figs. 31, 32 spec, from Little Belt (Mortensen 1900). Fig. 30 from the Sound St. 27 (iiSven Nilsson«). Fig. 30. Fig. 31. ced ones. The expansion of the parietal muscles on the column is considerable. Remarks. Among the Swedish species this species is the most nearly related to E. pallida. The arrangement of the nemathybomes is, however, another here, the number of tentacles in some cases greater, the smaller nematocysts of the nemathybomes shorter, etc. Edwardsia arctica n. sp. Dimensions. Physa ordinarily developed. Scapus with a rather well-developed periderm, especi- ally in the lower part. Nemathybomes somewhat large, probably arranged in 8 longitudinal rows, possibly a little scattered in the proximal part. Nematocysts of the nemathybomes 38 — 60 X 4 — 5 ,u, those of the 40 ACTINIARIA capituluni about 14 /i long. Tentacles 16. Nematocysts of the tentacles 19 — 26 X 2 — 2,5 /i, their spirocysts 12 — 24 X about 3/1. Nematocysts of the actinopharynx partly 29 — 41 X 3 — 3.5 ,«, partly (24) 26 — 34 x 4 — 6 ft, the latter with discernible basal part to the spiral thread. lyongitudinal muscle-pennons with few, ID — 13 folds, only branched in the outer part. The outer lamellar part of the mesenteries attached to the pennon next to the outside. Parietal muscles ordinarily developed, in transverse sections through the distal part of the column looking like a half-opened fan. The expansion of the parietal muscles on the column considerable. Colour in alcohol, rusty- to ochreous-coloured, in the distal part sometimes dirty-grey. Dimensions in contracted state. I^ength to about 0.9 cm, breadth to about 0.35 cm. Occurrence. East-Greenland. Mackenzie bay north of Franz Joseph's fiord 12 — 35 m mud (Sw.- Polar-Exp. 1900. N. 17) 2sp., Scoresby Sound Famae islands 70°5'N. 22°33' W.5 — 9 m mud (Sw.-Greenland-Exp. 1899 No. 32) 5 sp. South M^s^ of the little Pendulum island 74°35' N. i8°23'W. 18 — 21 m mud and sand (Sw. Greenland Exp. 1899 No. 20) i sp. Jan Mayen7i°i2' N.8°28' W. 1275 m grey clay (Sw. Greenland-Exp. 1899 No. 17) i sp. (badly preserved and young specimen, determination dubious. Nova Zembla Matotschkin Sharr 2 — 5 fms. clay and sand (Nova Zembla-Exp. 1875 No. 80). Kara Sea 73°38' N. 63°45' E. 80 fms. shells (Nordenskiold-Exp. 1876, No. 38) 2 sp. Exterior aspect. The physa is ordinarily developed and perforated by apertures. The scapus is provided with a periderm, most developed in the proximal part, the distal part of the scapus is polygonal. The nemathybomes are rather large, possibly a little irregularly arranged in the proximal part; in the distal part they form an undulating row in the middle of each compartment. It is probable that the nemathybomes are grouped in 8 longitudinal rows, but as all the animals were very strongly contracted this arrangement may have been disturbed by the contraction. The capituluni is of usual appearance. The tentacles are 16 in number. The actinopharynx and the siphonoglyphe were not well preserved. Anatomical description. The ectoderm of the physa is high with scattered nematocysts, 10 — 14 ju long. To the physa foreign bodies sometimes adhere. The ectoderm of the scapus is rather high with an or- dinarily developed periderm, to which a great many foreign bodies are sticking. The nematocysts of the nemathybomes are numerous. A general view of the size of the nematocysts of the examined specimens shows as follows. Habitat scapus tentacles actinopharynx n(a) actinopharynx n(b) Mackenzie bay 48-60 X 5,11 38-58 X 4 41-50 41-50 X 4-5 43-53 X 4-5 22-26 X 2.5 ^t 22-24 X 2.5 22-24 X 2.5 19-24 X 2-2.5 34-38 X 3-5," 34-41 X 3-5 29-36 X 3.5 34-36 X 3 31-34 X 5-6," 26 X 5 (few observed) Famae Islands PendiJuin I.sl Matotschkin Sharr Kara Sea 24-29 X 4-5 in the (b) nematocysts of the actinopharynx the basal part to the spiral thread is discernible. ACTINIARIA 41 The ectoderm of the capitulum is high and contains scattered nematocysts, about 10 — 12 /i long. The ectoderm of the tentacles is provided with numerous nematocysts 19 — 26 x 2 — 2.5 fi, and very numerous spirocysts, 12 X 1.5 — 24 X 3 //. The actinopharynx-ectoderm contains, in addition to the nematocysts '^=^ \ Fig- 33- F'g- 34- Fig- 35- Fig. 36. Fig- 37- Fig. 38. Edwarclsia arctica. Transverse sections of pennons (fig. 33 — 35) and parietal muscles (fig. 36 — 38) in the reproductive tract. Figs. 33, 36, specimen from Scoresby Sound, figs. 34, 37 specimen from Mackenzie Bay. Figs. 35, 38 specimen from the Kara Sea. mentioned in the table above, also smaller nematocj-sts, 19 — 26x2^ — 2.5/^; possibly these latter belong to the involved tentacles. The imperfect mesenteries are verj' weak. The longitudinal muscle-pennons of the 8 "Edwardsia- mesenteries" are not strong and form in the reproductive tract about 10 — 13 only slightly ramified folds. The sections through the reproductive region of three specimens, textfig. 33 spec, from Scoresby Sound (a), textfig. 34 spec, from Mackenzie Bay (b) , and textfig. 35 spec, from the Kara Sea (c) show a great conformity in the arrangement of the folds. The endoderm on the opposite side of the muscle-pennons is strongly lobed, The Ingolf-Ex-pedition. V. 9. g ACTINIARIA 42 the most conspicuously in the specimens a and b ; in c the folds are sticking together so that the outline seems to be more even. On the pennon-side the endoderm is, on the other hand, richly provided with vacuoles. The outer, lamellar part of the mesenteries is attached to the pennon, close by its outside. The parietal muscles (textfigs. 36 — 38) are comparatively strong, now fan-shaped, now — especially in the distal part — elongated towards the centre. The shorter folds are mostly situated in the inner part of the muscle. The expansion of the parietal muscles on the colunm is rather considerable. The ciliated streaks are well-developed. The species is dioecious. Edwardsia fusca Dan. Edwardsia fusca n. sp., Danielssen 1890 p. 112, PI. 5, fig. 6, PI. 19, figs. 5 — 9. Diagnosis. Physa well-developed, ampuUaceous. Scapus with a well-developed, incrusted peri- derm, polygonal, with 16? rows of small nemathybomes. Their nematocysts about 31 — 36 X (2) — 2.5/^. Capitulum polygonal. Tentacles 12. Nematocysts of the tentacles 24 — 27 X 2.5 /i, their spirocysts 14 X 1.5 — 26 X 2.5 fi. Nematocysts of the actinopharynx 36 — 46 x 2,5 — 3 ju. lyongitudinal muscle-pennons of the mesenteries rather strong, in the ciUated tract with 15 — 20 especially in the outer part riclily ramified folds. Outer lamellar part of the mesenteries attached (in the ciliated tract) close by the outside of the pennons. Parietal muscles somewhat strong with rather numerous transversely elongated folds. Expansion of the parietal muscles on the column probably the ordinary one. Colour. Capitulum brownish-red with 12 rather broad, dark-auburn lines, between which paler longitudinal areas are observed. Oral disc flesh-coloured with two brown annuli of small, brown patches. Tentacles with 3 dark-brown annuU. Scapus brown, physa flesh-coloured (Danielssen). Dimensions in extended state: Length of the body, tentacles included, 5.5 cm, scapus 2.8 cm. Ca- pitulum 1.2 cm (Danielssen). The strongly contracted specimen, sectioned by myself, was about i cm long. Occurrence. 70°36' N. 32°35' E. 271 m clay. Bottom temperature i°9. (Norwegian North-Atl.- Exp. St. 262) I sp. Exterior aspect. The physa is ampullaceous, well-developed and provided with 8 fine, longitudinal lines (probably the discernible insertions of the mesenteries). The scapus is provided with a strongly incrusted periderm, its form is cylindrical. Between the insertions of the mesenteries there are 16 rows of small nemathybomes in all, two in each compartment (Danielssen). (In the specimen, examined by myself, the nemathybomes were indistinct and seem to be more irregularly arranged, it is therefore questionable, if the nemathybomes are arranged in such a way as stated by Danielssen. The mesenterial farrows were indistinct in the proximal part, distinct in the distal one.) The capitulum is well-developed, in the distal part, close below the oral disc, provided with 12 ridges, proximally reduced to 8. According to Danielssen there are papillae (nemathybomes?) in the physa as well as on the capitulum. (This statement is certainly not correct, as the nemathybomes of Edwardsia never appear on the capitulum nor on the physa.) The tentacles are 12 in number. The oral disc is inconsiderable. Actinopharynx and siphonoglyphe ? — The above descrip- tion is compiled from that of Danielssen, I have placed my own remarks in brackets. Anatomical description. Danielssen has described this species anatomically, but in most ACTINIARIA 43 cases erroneously. I have only been able to examine a specimen imperfectly, mainly in the region of the scapus. Though my observations need completing, I think that they may aid to characterize the species. The ectoderm of the scapus is very tliin in comparison to the mesogloea, the periderm tliick, and the small nemathybomes provided with (rather sparse?) nematocysts of a length of about 31 — 36/^ and a breadth of (2) 2.5//. The nematocysts were commonly not well preserved. Danielssen has reproduced a section through the scapus (PI. 19, fig. 7) giving a rather good figure of the scapus. The nematocysts of the tentacles are 24 — 27/.! in length and 2.5 /j in breadth, their spirocysts vary from 14 x 1.5/^ to 26 X 2.5 /j. The ectoderm of the scapus is provided with numerous gland-cells, the nematocysts of which are 36 — 46 X 2.5—3 H- The longitudinal pennons of the mesenteries are rather strong, in tlie region of the ciliated tract with about 15 — 20 folds, somewhat richly branched, especially in the outer part. The innermost fold is longer than the largest one of the middle part. The lamellar outer part of the mesen- teries are attached to the pennon close by its outer edge (textfig. 39). The parietal muscles were not well preser\'ed, strong with rather numerous, long folds, running parallel to the column. Their expansion on the column is probably the ordinary one, but it is difficult to decide, on account of the strong contraction of the muscles. The ciliated streaks are of the usual structure. Remarks. The anatomical figures 8 and 9, PI. 19 in the work of Danielssen are quite useless. The figure 9 illustrates nothing, and as to the figure 8 it need hardly be said that the capitulum and the actinopha- rynx are not sectioned, as declared by Danielssen, but only the scapus, of which one part is involved. Tliis confusion of the body-parts also ex- plains Danielssen's statement that the capitulum has papillae. In many other respects Danielssen's description is certainly wrong, for instance his account of the actinopharynx and of the reproductive organs, as well as his discover^' of acontia. Textfig. 39. Edwardsia jusca. Transverse section of pennon in the ciliated tract. Edwardsia andresi Dan. Edwardsia andresi n. sp. Danielssen 1890 p. 106, PI. 5, fig. 5, PI. 20. — — Dan., Appellof 1893 p. 12, PI. 3 fig. 19, Carlgren 1904 p. 542—543 fig. 8, Carlgren in Nordgaard 1905 p. 158. Diagnosis. Physa well-developed, perforated by apertures. Scapus with a thin, easily deciduous periderm. Nemathybomes accumulated in the middle Une of each compartment, but not forming a single, longitudinal row. Nematocysts of the nemathybomes 48 — 67 X 3-5—4 /^. those of the capitulum 10 — 12 /i in length. Tentacles 12, seldom 13 — 15. Nematocysts of the tentacles numerous, 24 — 29 (34) X 2 — 2.5 ji, their spirocysts numerous, from 12—14 X i— i-S// to 26 X 2.5 /i. A weak ventral siphonoglj'phe. Typical nematocysts of the actinopharynx (29) 36—43 X 3.5—5 l^. nematocysts with distinct basal part to the spiral thread 24 — 29 X 4—5 ,«. Longitudinal muscle-pennons of the mesenteries strong, in transverse-sections of 6» . . ACTINIARIA 44 the reproductive region rather elongated with some twenty to some thirty folds, somewhat ramificated, especially in the outer part of the pennon. The outer lamellar part of the mesenteries attached to the pennon not far from the outside of it. Parietal muscles very strong, in transverse-sections often more or less trianguloid with rather richly branched folds. The expansion of the parietal muscles on the column is considerable. Colour. Scapus green with a few brownish-yellow patches, capitulum and tentacles pellucid. At the uppermost margin of the capitulum some dots of a rather intense brown colour, placed two and two together on a milky-white ground, appear like a double ring — a brown one and a white one below. Tentacles of the extremities of a faint violet, extending like a fine line a short way down the aboral side ; they also have a brown anniilus at the base. Oral disc brown, of a somewhat paler colour than the brown actinopharynx (Danielssen). In preserved state the periderm is dirty-green or -grey, sometimes more or less dirty-ochreous- coloured. Dimensions in expanded state. Length of the column 9 cm, breadth of the same 0.8 — i cm, length of the tentacles 1.6 — 2 cm (Danielssen). In preserved and very contracted state the length amounts to 2.7 cm. Occurrence. Davis Strait. 66°35' N. 56°38' W. 318 fms. Bottom temp. 3°9 (Ingolf-Exp. St. 32) i sp. West Greenland. Bredefiord 220 — 310 m. (Rink-Exp. 1912 St. 64) i sp. Iceland 6 — 7 miles N. W. of Borgarfiord 85 fms. (Haller 1867) i sp. Beeren Island-Spitzbergen. 75°58' N. I3°i8' E. 350 m. (Sw. Spitzbergen-Exp. 1898 No. 41) I sp. Norway-Beeren Island. 73°27' N. 23°! i' E. 460 m. (Sw. Spitzbergen-Exp. 1898 No. 2) II sp. Norway Finmark Skjerstadfiord 320 m. (Nordgaard) 481 m.; Bottom temp. 3°2 (Norw. N. Atl.-Exp. 1877 St. 253) numerous sp. — — Lyngen 300 m bottom temp, between 3°5 and 3^65 (Nordgaard 1899) numerous sp. — — Ogsfiord (Sars labelled Edwardsia duodecimcirrata) . — — Tromso Faemes (1881). North Atlantic. 6i°4o' N. 3°ii' E. 220 fms. Bottom temp. 6°34 (Michael Sars-Exp. 1902 St. 51).). Skagerrak 139 fms., 300 fms. (J. Lindahl 1877) numerous sp. Exterior aspect. The physa is well-developed and perforated by apertures in such a way as described by me below in E. vegae. The long scapus is provided with a thin, sometimes transparent, rather easily deciduous periderm which sometimes may be incrusted with foreign bodies. In its contracted state the mesenterial furrows are very distinct, wherefore the scapus seems polygonal, and also when the scapus is extended, these furrows are rather conspicuous. According to the figure reproduced by Danielssen there is in each compartment a single, longitudinal row of nemathybomes. Such a regular arrangement I have never observed, neithe r in a type-specimen nor in the numerous specimens examined by myself. In the con- tracted specimens the nemathybomes are commonly more irregularly arranged, though collected in the ACTINIARIA 45 middle line between the insertions of the mesenteries. On transverse-sections two or exceptionally some more nemathybomes may simultaneously be hit in the middle line. Also in 3 expanded specimens (from Faemes, Lyngen (textfig. 18) and Davis Strait) I have observed the same irregular arrangement witli sometimes 2 or a few more nemathybomes besides each other. In strongly contracted individuals the nemathybomes appear very indistinctly, so that the scapus seems to be smooth. The capitulum is short, smooth, witli shallow, mesenterial furrows. It is not provided with papillae (nemathybomes?) as Danielssen says. Tlie number of tentacles is generally 12 which I have observed in a great number of specimens; I have found 13 tentacles once, 14 three times and 15 once. In the specimen from Bredefiord one tentacle was provided with an off- shoot at the base, another one was bifurcated, circumstances which are probably connected with a regeneration. The inner tentacles are — as usual in Edwardsia — shorter than the outer ones. The oral disc is small, the mouth oval. The actinopharynx is provided with 8 longitudinal furrows, a distinct ventral siphonoglyphe is present. Anatomical description: The ectoderm of the physa is of ordinary height with sparse, scattered nematocysts, about 12 ft long. In contracted specimens the mesogloea is in the periphery of the physa thicker than the ectoderm, thinner in the centre of it. Its endoderm is higher than its ectoderm and rich in vacuoles, as is usually the endoderm of the column. The periderm and the ectoderm of the scapus are thin. The nema- thybomes are rather large and, especially m the distal part of the column, provided with numerous, often a little cur\'ed nematocysts. Their size varies between 48 and 67 X (3) 3.5 — 4 fi. The following table shows the size of the nematocysts of a series of specimens: Habitat Faemes Iceland Skagerrak Lyngen Beeren Isl. — Spitzbergen Norway — Beeren Isl. . . . St. 51 "Michael Sars" ... Davis Strait scapus tentacles actinopharynx 48—67 X 3.5 /< 56—62 X 3-5—4 48—53 X 3—3-5 48—62 X 3.5 48—60 X 3.5 48—65 X 3-5 50—62 X 3—4 53—61 X 3—3-5 24—34 X 2.5 (3) ft 25—29 24 — 29 X 2 24 — 29 X 2 — 2.5 38— 40 X 3 5—4-5." 36—43 X 3 36—43 X 4—5 (29)— 43 X 4—5 34—41 X 4 The endodermal, circular muscles are well-developed. The ectoderm of the capitulum is high and provided with numerous, about 10—12 n long, thick-walled nematocysts. At the base of the ectoderm there is a well-developed layer of nerve-cells and fibrillae which Appellof (1893) was the first to observe and re- produce. The nematocysts of the tentacles are numerous, (concerning their size compare the table!), the spirocysts vary from 12 X i— 1.5 « to 26 X 2.5—3 ft. The longitudinal muscles of the tentacles and the radial muscles of the oral disc are well-developed. The ectoderm of the actinopharynx is high in the ridges, in the furrows lower, its nematocysts numerous. The siphonoglyphe is distinct and pro\'ided with longer cilia than the other part of the actinopharj'nx. The imperfect mesenteries in the most distal part of the body are comparatively well-developed. If only 4 of these are present, they are found in the lateral and ventro-lateral "Edwardsia'-compaTtments (textfig. 9). The longitudinal muscle-pennons (textfigs. 40—42) of the 8 perfect mesenteries are strong, in transverse sections through the reproductive tract rather elongated and provided with some twenty to some 46 ACTINIARIA thirty folds of ordinary height. These folds are rather richly branched, especially in the outer and in the innermost parts. The inner folds are commonly considerablj' shorter than the outer ones, and the outer part of the mesenteries attached close by the outside of the pennons. The parietal muscles (textfig. 43 — 45) are strong; in transverse-sections in the reproductive region and a little higher up more or less trianguloid and rather richly branched. The inner part of the parietal muscles displays short, somewhat thick folds. In the textfigs. Fig. 40. Fig. 41. Fig. 42. Textfigs. 40—45. Edwardsia andresi. Transverse sections of pennons (figs. 40-42) and parietal muscles (figs. 43- 45) in the upper part of the re- productive tract or a little above (fig. 41). Figs. 40, 43 spec, from Bredefiord. Figs. 41 type-speci- men. Fig. 44 spec, from Lyn- gen. Figs. 42, 45 specimen from Iceland (younger than the others). I'ig- 43- Fig- 44- Fig. 45- 43 — 45 I have reproduced the parietal muscles of three specimens from different localities. These figures plainly show the conformity of the three specimens, as do also the figures of the corresponding longitudinal pennons (textfigs. 40 — 42). The expansion of the parietal muscles on the column is rather inconsiderable. The ciliated and the intermediate streaks are well-developed, in the proximal part of the filaments there is a distinct boundary streak. Danielssen states that acontia are present, but that is certainly not so. The species is dioecous. Remarks. The description of the species given by Danielssen differs in several respects from mine. ACTINIARIA .- Among Danielssen's figures of the species only the figures i, 2, 3, 5 and 13 (PI. 20) are usable, but nowise good, the others are very bad. The section reproduced in the figure 7 has in the centre not hit the actinoplia- rynx, but the involved part of the column; the figures 10 and 11 show nothing as to the presence of acontia and testes. As already corrected by Appellof (1893 p. 18) this species has normally developed directive me- senteries. The above description of the species is based not only on a type-specimen but also on several individ- uals from different localities. Edwardsia islandica n. sp. Diagnosis. Physa rather well-developed. Scapus with a very strong cuticle and with rather few, scattered, small nemathybomes. Nematocysts of the nemathybomes 36 — 48 X 2— 2.5y«. Tentacles 16. The nematocysts of the tentacles about 22 — 24 x 1.5//, their spirocysts 12—17 x 2—2.5/1/? The nemato- cysts of the actinopharynx (33) 36 — 43 X 2 ^. lyongitudinal muscle pennons of the mesenteries somewhat strong with a few (to about 12) folds which are of about equal height and rather richly branched. Lamellar outer part of the mesenteries in the upper part of the reproductive region attached to the pennons not far from the outside of these latter. Parietal muscles, especially in comparison with the pennons, very strong, mostly trianguloid and with numerous folds. The expansion of the parietal muscles on the column is considerable. Colour? Dimensions: Breadth of the column 0.4 cm. As to the length I cannot give any exact information, the single specimen, dredged at the same time as E. tuberculata having been sectioned, and the tliickness of the sections not having been stated. Occurrence: South of Iceland 63^15' N. 22°23' W. 326 — 216 m (Thor-Exp.) i sp. Exterior aspect: The physa is rather well-developed. The scapus is provided with a very strong cuticle and with rather few, small, scattered nemathybomes. The capitulum is polygonal. Number of ten- tacles 16. The actinopharynx is strongly folded. I cannot decide whether a siphonoglyphe is present or not, the ectoderm of the actinopharynx not being well preserved. Anatomical description: The ectoderm of the physa was considerably higher than that of the scapus. The scapus-ectoderm is provided with a thick cuticle which in several places may become as thick as the ectoderm. The cuticle very much recalls that of Isoedwardsia ingolfi, though it is not quite as thick. It is strongly folded because of the strong contraction of the scapus. The small nemathybomes only contain a single kind of capsules 36—48 X 2—2.5 /i in size. The ectoderm of the capitulum is higher tlian that of the scapus. The nematocysts and spirocysts of the tentacles and the nematocysts of the actinopharynx I have only been able to measure in sections. The nematocysts of the tentacles are about 22—24 X 1.5 /i, the spiro- cysts about 12 — 17 X 2.5//; the latter measures are, however, very uncertain. Tlie numerous nematocysts of the actinopharynx were (33) 36—43 X 2 ;/. The nematocysts of the tentacles and of the actinopharynx are measured on sections. The 8 " Edwardsia" -m^senten^s are rather strong with some few (to about 12) folds wliich are of about equal height and show a tendency to rich ramification (textfig. 46). The smaU, imperfect mesenteries of the uppermost part of the column are thick. The parietal muscles, especially when compared with the 48 ACTINIARIA longitudinal pennons, are strong, trianguloid and provided with numerous folds, particularly in the upper part of the reproductive tract (textfigs. 47, 48) . The expansion of the parietal muscles on the column is considerable and comprises about the whole breadth of the parietal muscles. The ciliated streaks are well-developed. The specimen was a male. Fig. 46. Fig- 47- Fig. 48. Textfigs. 46 — 48. Edwardia islandica. Transverse section of pennon (fig. 46) and parietal muscles (figs. 47, 48) in the upper part of the reproductive tract. Edwardsia incerta n. sp. Diagnosis: Physa well-developed. Scapus with a thick ectoderm, incrusted with foreign bodies, with scattered, large nemathybomes, containing a few nematocysts 29 — ^J X 5 /i in size. Tentacles not more than 16, probably 12. Nematocysts of the tentacles 22 — 26 x 2 fx, the spirocysts 14 — 22 n in size. Longitudinal muscle pennons of the mesenteries in transverse-sections with some few, about 12 folds, only ramificated in the outer parts. The lamellar outer part of the mesenteries attached close by the outside of the pennons. Parietal muscles comparatively well-deve- loped, in transverse-sections fan-shaped, considerably broader than in E. arctica. The parietal muscles are considerably expanded on the column. Colour in alcohol: Scapus dirty grey. Dimensions in contracted state: length 0.9 cm, breadth o. 15 cm. Occurrence: East-Greenland 72°28' N. 2i°48' W. 180 m mud with some stones (Sw. Greenland-Exp. 1899) i sp. The muscle pennons of the mesenteries of these species recall those of E. arctica ; the nematocysts of the nemathybomes, however, differ in size. On account of the imperfect and badly preserved material I cannot give any minute description of the species. A transverse-section of a nmscle pennon Textfig. 49. Edwardsia incerta. Compare the text! and of a parietal muscle is reproduced in textfig. 49. ACTINIARIA .- 49 Edvvardsia vitrea (Dan.) Carlgr. PI. I, Figs. 5, II. Edwardsioides vitrea n. sp. Danielssen 1890, p. 100, PI. 5, fig. 3, PI. 16, figs. 4—10. Diagnosis: Physa rather weU-developed. Scapus with a very tliin periderm, with scattered nemathy- bomes, the nematocysts of which are (34) 36—42 X 3—3-5 f- Number of tentacles 13—16. Nematocysts of the tentacles 17—29 X 2.5—3.5 /A the spirocysts unto 29 X 2.5—3.5 ,«• Nematocysts of the actinopha- rynx very numerous, partly (31) 36—53 x 2.5—3.5 A, partly 17—24 x 2.5 [i. Longitudinal muscle pennon strong, in the upper part of tlie reproductive region with 20—30 longer and shorter folds, the former with numerous, small secondary folds. The outer lamellar part of the mesenteries attached close by the outside of the pennon. Parietal muscles very strong, in transverse-sections through the reproductive tract often trianguloid, with ver>' numerous, long, clo.sely packed folds. The expansion of the parietal muscles on the column the ordinary one. Colour: Periderm greenish, transparent. The integument inside almost as clear as glass, with a faint play of reddish colour and with pale hght-red longitudinal furrows. In fully expanded state the capi- tulum has a faint, rose-red tinge, and so has the physa. Tentacles beautifully bright-red (Danielssen). Scapus in preserved state dirty-grey or partly ferruginous. Dimensions in extended state: 4 — 5 cm in length and 0.8 cm in breadth (Danielssen). In con- tracted state the length is to about 3 cm and the breadth to about 0.7 cm. Occurrence: East-Greenland Franz Joseph Fiord 73°i6' N. 23°i5' W. 28 — 36 m clay with stones sand and shells (Sw. Greenland-Exp. 1899 No. 44) 2 sp. Spitzbergen Wijde bay 40 fms. (Sw. Spitzberg-Exp. 1861) i sp. Great fiord 78°37' N. 19° E. 5—10 fms. Sand (Malmgren 1864) 3 sp. Great Islet 8o°i5' N. 30° E. 95 m (Romer and Schaudinn St. 37) i sp. 68°2i' N. io°4o' E. 836 m clay and sand. Bottom temp. — 0.7 (Norw. N. Atl.-Exp. St. 164) I sp. Exterior aspect: The physa seems to be smaller than in the former, species described. Accord- ing to Danielssen it is incapable of involution ; this is probably not correct. In the examined type-specimen (fig. 5, PI. i) the scapus is separated from the physa by an annular lacing in. Danielssen also states that the physa is provided with sparse suckers (nemathybomes?). This is certainly not the case, I never observed any such. On the other hand foreign bodies sometimes seem to be attached to the physa ; in the type-spec- imen there were namely fragments of such adhered to the physa, probably by the secretion of the mucus-cells. According to my examination of the species from Great Islet, the physa of which I have sectioned, the physa is perforated by apertures. The scapus is provided with 8 longitudinal furrows, corresponding to the insertions of the mesenteries, and with scattered, rather numerous nemathybomes. Danielssen declares that the suck- ers (nemathybomes) are arranged in somewhat regular transversal rows which, however, does not seem to be case. The periderm of the scapus is ven,' thin. When the animal is very much expanded the periderm is almost inconspicuous (Danielssen). The involved part of the scapus is a little polygonal. The capitulum is short and provided with distinct, longitudinal furrows, corresponding to the insertions of the mesenteries. The logolf-Expeditioo. V. 9. 7 50 ACTINIARIA The statement of Danielssen, that the capituluni has suckers, is not correct. The tentacles were i6 in the specimen from Great fiord, Wijde bay and in the examined type-specimen; the specimens from Greenland had only 13, resp. 15 tentacles. The specimen from Wijde bay (PI. i, fig. 11) showed a neomorphose (Carl- gren 1904 p. 458). The oral disc is small, the actinopharynx as usual short. Siphonoglyphe ? Anatomical decription: The apertures of the physa are surrounded by circular muscles. At the aperture in the mesogloea there is an annular wall of the epitheHum (whether of the ectoderm or of the endoderm I cannot decide, the epithelium not being well preserved). This wall probably forms a movable stop- Textfigs. 50 — 51. Edwardsia vitrea. Section of a central aperture in the physa fig. 50 through the middle part fig. 51 through the rim. cm. circular muscles. Fig- 50- Fig- 51- ping, differently located according to the different state of concentration of the physa. In the Wij de-specimen the waU turned towards the ectoderm, (textfigs. 50, 51), while in E. vegae (compare this species) it turned in- wards. The wall is almost exclusively composed of elongated cells with large nuclei. The nemathybomes of the examined type-specimen are flat and, on account of the bad preservation, containing only a few whole nematocysts, the greater part of which are shrivelled, and as the stinging thread is thrown out there is no distinct limit between the capsule and the thread. The nematocysts in the nemathybomes of the other spec- imens were numerous, excepting the badly preserved Wij de-specimen where I found only a few nematocysts. In the following table I have set up the size of the nematocysts in the different tracts of the animal. It ought to be mentioned that the nematocysts are measured only in sections of the type-specimen. The measures are therefore a little uncertain. Habitat scapus capitulum tentacles actinopharynx Great fiord 68°2i'N (typesp.) East-Greenland . . . Wijde bay 36—38 X 3.5 ,u about 38 37—42 X 3—3-5 34—38 X 3 14 17 X 2 U 14 17 X 2 10 12 24—29 X 2.5—3.5 U 17—29 X 2.5—3.5 19—25 38—51 X 3.5 ^( 36—53 X 3 36—48 X 3-5 31—36 X 3 17- 20- -22 1.1 -24 X 2.5 In the specimen from Wijde bay I found only 2 nematocysts in the maceration preparation of the nemathybomes, and in the specimen from Great Islet none, (as the parietal muscles of the latter are very strong it is, however, probable that we have to do with E. vitrea). The periderm of the scapus is very thin and only a little incrusted. The nematocysts of the capitular ectoderm are rather numerous, in the tentacles very numerous. The spirocysts of the tentacles obtain a size ACTINIARIA 51 of 17—29 X 2.5—3.5 n, I have also observed smaller capsules. The ectoderm of the actinopharynx is high, several times thicker than the mesogloea, and contains nematocysts of two different sizes. The longitudinal muscle pennons of the mesenteries are strong. Unfortunately I cannot describe the pennons of the type specimen in the upper part of the reproductive tract as Danielssen has sectioned this Fig- 52- Fig- 53- Fig- 55- Fig. 56. Fig. 54- Textfigs. 52 — 56. Edwardsia vitrea. Transverse section of pennons in the upper part of the reproductive tract (figs. 53, 54) or in a corresponding part (fig. 52). Fig. 52 joung specimen from Wijde Bay, fig. 53 spe- cimen from Franz Joseph Fiord, fig. 54 spe- cimen from Great fiord. Figs. 55, 56 Trans- verse section of a mesentery of the type- specimen, fig. 55 through the lower part of theactinopharyngial region, fig. 56 through the lowest part of the reproductive tract. part; on the other hand I have been able to examine the pennons of the lowermost part of the actinopharynx region (textf. 55) and of the lowest part of the reproductive tract (textfig. 56). In the latter figure we see that the pennon begins to diminish, showing however numerous branched folds, especially at the outer side. In the former sections we find about 30 high, rather richly ramificated folds, of about equal height. I have reproduced pennons in the upper part of the reproductive region of the specimens from Great fiord (textfig. 54), from Greenland (textfig. 53) and from Wijde bay (textfig. 52); they aU agree well. The folds are about 25 30 in number and provided with numerous, small, secondary folds. The outer lamellar part of the mesen- 7* 52 ACTINIARIA teries is attached close by the' outside of the pennon. The parietal muscles are very strong, in the inner part commonly more branched than in the outer one, where the high folds sometimes have no branches at all. The folds are numerous and, especially towards the outside, closely packed together. According to the state of contraction the parietal muscles of transverse-sections are of a different appearance; they are, however, Fig- 57- Fig- 58- Fig. 59- Fig. 60. Fig. 61. Textfig.s. 57 — 61. Edwardsia vitrea. Transverse section of parietal muscles. Fig. 57: young specimen from Wijde Bay, fig. 58 specimen from Franz Joseph Fiord, fig. 59 specimen from Great Island, fig. 60 specimen from Great Fiord, fig. 61 type-specimen. more or less trianguloid. For comparing purposes I have reproduced the parietal muscles of five specimens. Especially the muscles reproduced in the figs. 58, 60, and sectioned in the upper part of the reproductive region, do very well agree. The distribution of the parietal muscles on the column is the ordinary one. The ciliated tracts are of usual appearance. The type-specimen as well as the other examined specimens were females. I cannot confirm Danielssen's statement that the species is monoecious. Also in other respects Daniels- sen's description is erroneous. ACT INI ARIA 53 Edwardsia vegae n. sp. Diagnosis: Physa weU-developed, perforated by apertures. Scapus with a rather well-developed periderm, polygonal, with scattered, especially in the lower part large nemathybomes. Nematocysts of the physa 14—19 fi, those of the nemathybomes 84—101 x 3 /^ those of the tentacles 19—24 x 2 //, those of the actinopharynx 38—43 X 3 Z'- Tentacles 16. Longitudinal pennons of the mesenteries in the reproductive region with about 25—30 strong folds which are rather high and richly ramificated in the outer part, low and only sUghtly branched in the inner one. Outer lamellar part of the mesenteries attached to the pennon at some distance from its outside. Parietal muscles with somewhat numerous, in the outer part closely packed folds; in transverse-sections through the re- Textfig. 62. Edwardsia vegae. I/jn^ituciinal section of the involved physa and of part of the scapus (sc), en : endoderm, ec : ectoderm, a : annular wall. ^■?SV' small, but numerous and scattered. The sea- • x?^-^^, pus seems to be smooth, because X \^^ ^ the nemathybomes only rise a little or not at all over the sur- face, in contracted as well as in expanded individuals. The proxi- mal part of the scapus is almost round, the distal part polygonal, probably on account of the con- traction. The capitulum is short. The number of the tentacles va- ries considerably. Of 5 examined specimens one had 16, two 22, one 23 and one 26 tentacles, ar- ranged in two or three cycles. The oral disc is small, the actinopha- rynx short. A ventral siphonogly- phe is present. Anatomical descrip- tion: The nematocysts of the physa are 12 — 14 fi in length. The apertures are surrounded by cir- cular muscles. The numerous ne- matocysts of the nemathybomes vary considerably in size, they are commonly 31-44 ,« long, sometimes shorter, down to 26 f., sometimes longer, unto 62 ;.. The ectoderm of the capitulum is rather thick, with sparse nematocysts, 10-12 ^ long. The high ectoderm of the tentacles contains numerous nematocysts (22-26x2.5 -3 i^) andspirocysts (14-17 /. long). The ectodermal longitudinal muscles of the tentacles are rather well- developed. The ectoderm of the actinopharynx is high and provided with several ridges; its nematocysts are numerous, 30-35 X 2.5-3 /. in size. The ectoderm of the siphonoglyphe contains very few nematocysts and glandceUs; its cilia are longer than in the other part of the actinopharynx. The imperfect mesenteries in the uppermost part of the column are rather strong. The longitudinal Fig. 65. Fig- ('T- Textfig. 65—67. Edwardsia finmarchica. Transverse section of pennon (fig. 65) and of parietal muscle (fig. 66) in the reproduction tract. Fig. 67 Transverse section of parietal muscle in the lower part of the actinopharynx. 56 ACTINIARIA muscle pennons (textfig. 65) of the"Edwardsia-mesenteries" are very strong, and in transverse-sections through the upper part of the reproductive tract elongated with about 50 folds. These latter are of ordinary length and rather richly branched, especially in the inner and outer parts (several specimens sectioned) . Between the lai-ger folds there are smaller ones (textfig. 65). The outer lamellar part of the mesenteries is commonly attached close by the outside of the pennon, sometimes a Uttle more inwards. The parietal muscles are, in comparison with the pennon, not particularly strong; in transverse-sections through the reproductive tract often trian- guloid (textfigs. 66, 67) with the longest folds next to the outside. There are not many folds, and they are only a little ramificated; further upwards (textfig. 67) they are more numerous, but never reach the number of folds in E. vitrea. The parietal muscles are not at all, or only very slightly expanded on the column. Typic- ally ciliated tracts are present. The species is dioecious. Remarks: The species is probably nearly allied to E. sipunculoides, but differs from this species in longer nematocysts in the nemathybomes and more richly branched muscle pennons. Genus Isoedwardsia Cmigr. Diagnosis: Edwardsiinae with the column divisible into two regions, capitulum and scapus. Prox- imal part of the body rounded and, as the other part of the scapus, furnished with nemathybomes. Nemato- cysts of these latter long and thin. Nemathybomes scattered or arranged in several hues. Scapus with a more or less well-developed cuticle. Nematocysts in the cuticle-lacking ectoderm of the capitulum small. Ten- tacles 16 or more. Only one feebly developed ventral siphonoglyphe ? This genus, characterized by myself in a few words (1900, p. 26), is distinguished from the nearly related genus Edwardsia by the absence of any trace of a physa, while a physa is always present in Edwardsia, even if it is sometimes rather small. The ectoderm of the rounded, proximal part of Isoedwardsia is there- fore furnished with a cuticle which is wanting in this part of Edwardsia. Both genera are also differentiated from each other in this respect that the physa never contains nemathybomes in Edwardsia , while in Iso- edwardsia the most proximal part of the body has nemathybomes. Possibly the presence of discontinuous, ciliated streaks which are very distinct in /. mediterranca n. sp. also is of systematic importance and char- acteristic of the genus, but till now we know too httle about the occurrence of this structure to be able to use it as a genus character. The type of the genus is /. ingolfi. Besides this species I have in the Mediterranean found another one which I wiU call /. mediterranea. It is possible that the latter has been described before as an Edwardsia, though at present it cannot be identified with any before known species. The cuticle is much thicker in /. ingolfi than in /. mediterranea ; in the former the muscle-pennons show about 30 folds in the reproductive regions, in the latter about 70. In another paper I will describe a third species, dredged at the Easter Island. Isoedwardsia ingolfi n. sp. PI I. Figs. 36, 37. Diagnosis: Cuticle very thick, especially in the proximal part of the body, ectoderm of the scapus thin, also in the proximal part. Nemathybomes numerous, scattered on the scapus. Nematocysts in the ACTINIARIA 57 nemathybomes 50 — 60 X 4 — 5 ^, in the tentacles 31 — 36 X 3 //, in the actinopharynx 41 — 46 X 3—4 fi. Tentacles 16. Longitudinal muscle-pennons of the mesenteries in the reproductive region strong, with about 30, often ramificated folds. Outer parts of the mesenteries issuing not far from the middle of the pennon, Parietal muscles in the reproductive region in transverse-sections oval, with rather richly ramificated folds. Their expansion on the column is inconsiderable. Colour in preserved state: scapus dirtily ochreous-j-ellow shading off into grey. Fig. 70. Textfigs. 68 — 72. Isoedwardsia ingolfi. Fig. 68: Section of a portion of scapus in its proximal part. Fig. 69: Section of a portion of .scapus in the middle of the aboral body-end. Fig. 70: Transverse sec- tion of a pennon in the reproductive region. Fig. 71: Transverse section of a pa- rietal muscle in the reproductive region. Fig. 72: Transverse section of a mesen- tery in the proximal part. Dimensions: Spec, i) Length i.i cm., largest breadth, a little above the proximal part of the animal, 0.5 cm. Length of capitulum 0.5 cm. Sp. 2) Length 2.1 cm, largest breadth 0.6 cm (PI. i, fig. 36). Occurrence: 6o°37' N. 27° 52' W. 799 fms. Temperature of the bottom 4.5° (Ingolf-Exp. St. 78) 2 sp. Exterior aspect: No physa. The most proximal part of the column is rounded, broader than the other part of the body and totally cuticle-clad (Pi. i, fig. 36). Scattered nemathybomes appear also in the most proximal end which is more soUd than the other part of the body. The proximal end imperceptibly fuses into the other part of the scapus, the cuticle of which is also strong. In all places on the scapus there are scattered nemathybomes wliich are especially distinct in the smaller, more extended specimen. The longitu- The Ingolf.Expedition. V. 9. " 58 ACTINIARIA dinal furrows, corresponding to the insertions of the mesenteries, are rather distinct on the scapus. The capitulum is smooth, transparent, without a cuticle and with distinct longitudinal furrows where the mesen- teries insert. The tentacles are badly preserved and stick together, conical, on the larger specimen very extended lengthwise (PI. i, fig. 37) ; 16 in number. The oral disc and the actinopharynx are very macerated. Anatomical description: The distal parts of the animal are very badly preserved, so that I cannot give any exact description of the structure of the actinopharynx, tentacles or mesenteries of these parts. The ectoderm of the scapus is, in comparison with the mesogloea, very thin, especially in the proximal parts; gradually the ectoderm increases in thickness towards the distal end. Outside the ectoderm there is a very characteristic layer which reaches a considerable thickness, especially in the proximal body-end (textfigs. 68, 69 a) . In these places this layer is many times thicker than the ectoderm and sometimes almost as thick as the mesogloea from which it only differs a httle in structure. While in the homogeneous ground-substance of the mesogloea we rather commonly find fibrillae, but only rarely cells — the part of the mesogloea turned to the endoderm is stained more intensely with borax-carmin and haematoxylin than the outer part which remains almost unstained — the layer outside the ectoderm is more homogeneous, though fibrillae and cells also here exceptionally appear, and is only weakly stained with the above-mentioned colouring matter. This layer outside the ectoderm much recalls the so-called sub-cuticle of the Zoantharia, and this Ukeness is still more conspicuous, in as mush as a thin, brownish cuticle, to which extraneous bodies are sticking, occurs outside the homogeneous layer in I soedwardsia as well as in Zoantharia, thus forming the outside of the surface of the body. Towards the distal part of the scapus this "sub-cuticular" layer is thinner and does not in its most distal part attain the thickness of the ectoderm. The nemathybomes are of about the same structure as in Edwardsia (textfigs. 68, 69 ne) ; they con- tain numerous, rounded, somewhat irregular bodies, surrounded, as it seems, by a refractive, tliick mem- brane. The nematocysts (m) which in the scapus appear only in the nemathybomes and attein a size of 50 — 60 X 4 — 5 (1, are sometimes a httle curved, with the basal part to the spiral thread a httle translucent. On the reproduced sections, especially on the textfigure 69, they are obliquely sectioned. The ectoderm of the capitulum is higher than that of the scapus and on one specimen sticking to the tentacles. The ectoderm of the tentacles contains numerous, thick-walled nematocysts (their size 31 — 36 x 3 ^). The spirocysts of the tentacles are of variable length, the longest about as long as the nematocysts in the same part, but about twice as broad. The nematocysts of the actinopharynx are numerous, 41 — 46 n long and 3 — 4 p. broad. The longitudinal muscle-pennons are in the reproductive region, in transverse-sections, elongated with about 30, not densely packed, very often ramificated folds. The larger folds are of ordinary height and almost all of about equal size, the lower folds are sparse (textfig. 70). The parietal muscles are in transverse-sections in the reproductive region oval, with shorter folds in the inner and the outer parts. The folds are often rami- ficated, numerous and spreading apart (textfig. 71). As to the filaments they are not well preserved in the distal part, but in good condition in the reproductive region. It seems as if they are hke those of I. medi- terranea, in which the ciUated streaks are discontinuous. Inside the glandular streaks which contain numerous nematocysts, but rare gland-cells, there is, in this species, a well differentiated part, an intermediate streak with rare nematocysts and numerous gland-cells. The reproductive organs were in the one, particularly examined specimen, testes with well developed spermatozoa. ACTINIARIA 59 Subfam. Milne-Edwardsiinae. Diagnosis: Edwardsiidae without neniathybomes in the scapus. Nematocysts in the ectoderm of the scapus scattered or in heaps. Physa absent, indistinct or feebly developed. Nematocysts of the capi- tulum of almost the same size as those of the scapus. Inner tentacles longer than the outer ones ; commonly hexamerously arranged. This subfamily corresponds to the family Milne-Edwardsiidae, proposed by myself (1893, p. 11), and is easily distinguished from the subfamily Edwardsiinae by the absence of nemathybomes. Also the arrangement of the tentacles is another one, at least in the genus Milne-Edwardsia, but probably also in Paraedwardsia as I have been able to state the same arrangement in P. sarsii as in Milne-Edwardsia. The tentacles are namely commonly hexamerously arranged, and the inner tentacles are larger than the outer ones (textfig. 11), so this is another agroupment than that of the genus Edwardsia. Concerning the num- ber of siphonoglyphes I can ascertain that several species have only one, a ventral one. Whether this is characteristic of the whole subfamily, remains to be confirmed. This subfamily does not seem as rich in species as the subfamily Edwarsiinae. Very likely the num- ber of Milne-Edwardsia-s-pecies will increase, when all Edwardsiidae have been subject to a more detailed examination. There is no doubt that several species, described as Edwardsiella and Edwardsia, belong to this subfamily. Thus, according to my examination, the Edwardsia timida Quatr. is a Milne-Edwardsia, M.dixonii, (verified by myself on material received from Dixon). Besides this, it is not improbable that one part of the forms, described and reproduced by Andres 1883 as varieties of Edwardsia claparedii, are in fact Milne-Edwardsia- or Paraedwardsia-s^eci&s. In the subfamily I included two genera Milne-Edwardsia and Paraedwardsia, of which the latter is furnished with "i7a/cflw/)«-papillae", the former not. Genus Milne-Edwardsia Caiigr. Diagnosis: Milne-Edwardsiinae with the column divisible into a lower, greater part which is invested with a rather well-developed, sometimes very thick cuticle and an upper minute part, capitulum, without cuticle. A weak physa also sometimes present. Scapus without nemathybomes and " Halcampa-papUlsie" . Nematocysts in the ectoderm of the scapus either scattered or arranged in groups, comparatively short, in proportion to the breadth. Nematocysts of the capitular ectoderm commonly large and mainly distributed on the ridges of the capitulum. Capitulum more or less polygonal. Tentacles 12 or in several cycles, hexa- merously arranged, the inner longer than the outer ones (alvays?). Only one, ventral siphonoglyphe (always?). In a certain respect the diagnosis of this genus, pubhshed in this paper, is a httle more exphcit than the original one. The hitherto known species of this genus are: M. loveni Carlgr., M. carnea (Gosse), M. polaris Carlgr., M. nathorstii Carlgr. and M. dixonii Carlgr. (nov. nomen pro "Edwardsia timida Quatr." described by Dixon). It is also possible that Edwardsia lineata Verr. will be included in this genus. The species described below are easily distinguished from each other. 8* 5o ACTINIARIA Milne-Edwardsia loveni Carlgr. PI. I. Figs. 32, 33. Milne-Edwardsia loveni n. sp., Carlgren 1892, p. 456, textfig. 3, 1893, p. 17, textfigs. 3, 4. PI. i, figs. 6 — 8, PI. 2, figs. I — 4, PI. 10, fig. 3. — — — Carlgr. Arndt 1912, p. 123. Diagnosis : Nophysa. Proximal part of the body of variable appearance, on account of the habits of the animal. Scapus more or less polygonal, with a very strong, often rugous, easily deciduous cuticle. Nematocysts of the scapus scattered, mainly arranged on the ridges, in the lower part about 24 ju long, in the upper 38 — 48 X 6 u. Capitulum distinctly polygonal with sharp ridges. Nematocysts mainly on the ridges 22 — 30 X 4 /^. Nematocysts of the tentacles about 22 x 4 //. Number of the tentacles to about 30 — 40. Nematocysts of the actinopharynx partly 17 — 19 /i, partly 24 — 29 X 3 /7. Longitudinal muscle-pen- nons strong, in the upper part of the reproductive organs with about 20 — 30 folds. Colour: Mouth, actinopharynx and reproductive organs brick-red; tentacles and capitulum flesh-coloured. Mesenteries and scapus inside the cuticle of the same colour as the tentacles, but paler, some- times white. Cuticle of the scapus grey, shading off into brownish-yellow. Dimensions : Length of the body to about 3,5 cm, of wliich the capitulum is a fourth part. Largest breadth to about 0,5 cm. Length of the tentacles about 0,35 cm. Actinopharynx one half or two thirds of the length of the capittilum. Occurrence: Sweden. Bohuslan. Vaderoame about 50 fms. in dead Lophohclia (Loven, 01s- son, Carlgren, Auriwillius and others). Kosterfjord. Sneholmen 60 — 120 fms. (Auriwillius) Ramso S. Koster 60 — 120 fms. (Auriwillius). Norway. Drontheim fiord. Skarnsund 100 — 220 m in dead Lophohelia and Para- gorgia (Oestergren, Mortensen 1911), Rodberg 150 — 200 m (Oester- gren and Arwidsson) 100 fms. on "Duva rosea" 200 — 400 m (Arndt). Mosterhavn 150 fms. on Lophohelia, Selsovig 100 fms. (G. O. Sars). Finmark. North Cape on a Brisinga 350 fms. Exterior aspect: The body is extended and more or less irregularly curved, because the animal commonly lives in the dead calyces of Lophohelia. No physa is developed, the proximal end now broad, now pointed. The scapus is invested with a firm, very thick, almost coriaceous, irregularly folded cuticle, not equally wide, but here and there irregularly thickened, sometimes thicker than the capitulum, and in the distal part sometimes with 8 pronounced longitudinal furrows (PI. i, fig. ^^), corresponding to the insertions of the mesenteries. These furrows are prolonged downwards, but becoming less distinct. The cuticle of the scapus is easily deciduous, in the distal part often thinner than in the proximal part. The capitulum shows 8 high ridges, each placed midway between two insertions of the mesenteries. If the capitulum is strongly contracted, the ridges appear like distinctly outlined, folded ribbons (Carlgren 1893, PI. i, fig. 8). The most distal part of the capitulum is thinner than the other part of it. The tentacles are between 30 — 40 in number, in younger specimens fewer, hexamerously arranged, in three or four cycles, short, cyUndrical; the inner tentacles a little longer than the outer ones. The oral disc is small, with radial furrows correspond- ACTINIARIA 6i Textfigs. 73—75- Milne-Edwardsia loveni. Fig. 7,5. Transverse section of pennon in the upper part of the reproductive tract. Kig. 74. Transverse section of a portion of capitulum with a parietal muscle. I''ig. 75. Transverse section of a portion of the capitulum n : neraatocysts. ing to the insertions of the mesenteries. The actinopharynx is short, with 8 longitudinal ridges and as many longitudinal furrows. The siphonoglyphe is ventral, indistinct, about twice the breadth of the other longi- tudinal furrows in the actinopharynx. Anatomical description: The scapus-ectoderm is high, especially in the proximal part and on the ridges, and several times thicker than the mesogloea; also in the distal parts it is higher than the meso- gloea. The nematocysts are few in number between the ridges, on these latter very numerous but scattered and do not seem to form any such groups as in M. carnea. They are most frequently a Uttle curved, with rather indistinct basal part to the spiral thread which follows the whole length of the capsules, and they are 36 — 48 X 6// in size. Further down there are also smaller capsules, about 24 fjL long. The cuticle of the scapus is very thick, the outer part of it is rather easily loosened from the under- lying, thinner substitutive-cu- ticle, and is a little incrustated. The ectoderm of the capitulum is in the ridges high, with numerous nematocysts, 22 — 30 // long and 4// broad; in the furrows lower, with very few nematocysts (textfig. 75). The mesogloea is much thicker on the ridges than in the furrows, where it is rather thin. The endodermal circular muscles are weak and form no sphincter. The ectoderm of the tentacles contains ver>' numerous nematocysts, about 22 X 4 /.( in size, and spirocysts of variable length; the largest are of about the same size as the nematocysts. The ectoderm of the actinopharynx is high on the ridges and many times higher than the mesogloea, with comparatively rare nematocysts, partly smaller, 17 — ig^yz long, partly larger, 24 — 29 X 3 /.i, and numerous gland-cells. The nematocysts are mainly arranged on the ridges; in the furrows they are very few. The siphonoglyphe is only a httle differentiated from the other part af the actinopharynx. The mesogloea is a little thickened on the insertions of the mesenteries and ends in a thin lamella. The weak, imperfect mesenteries are rather thick. The longitudinal pennons of the 8 perfect mesen- teries are in the reproductive region provided with 20 to 30 folds wliich are of about equal height and rather much ramificated (textfig. y^,). The outer lamellar part of the mesenteries issues very close by the outer edge of the pennons. The parietal muscles (textfigs. 74, 75) are well developed, with thin folds of a charac- teristic appearance. They appear fan-shaped on transverse-sections; the lamellar part of the mesenteries issues from the base of the fan. The cihated streaks are present, though not long. The animal is dioecious. Biology : The animals live in dead coral-branches of Lophohelia and Paragorgia, sometimes on Fig- 73 .^ 62 ACTINIARIA other Octo-corals or on Brisinga. In contradistinction to the genus Edwardsia they do not show any reac- tions to light or to shade. Remarks: This species has before been described by me in detail (1893, p. 17); I have here com- pleted the description mainly with regard to the stinging capsules. Concerning further details I refer to tliis work. Milne-Edwardsia carnea (Gosse) Carlgr. Edwardsia carnea n. sp. Gosse 1856, p. 219. PI. 9, figs, i — 4. — — Gosse, Gosse 1858, p. 418, Gosse i860, p. 259, PI. 7, figs. 5 — 6, PI. 12, fig. 3, Hincks 1861, p. 363, Haddon 1889, p. 328, PI. 33, fig. 15, PI. 36, figs. 5—6. Bourne 1916, p. 25, textfig. 2. Edwardsiella — — Andres 1883, p. 99, Pennington 1885, p. 178. Milne-Edwardsia — (Gosse) Carlgren 1892, p. 456, figs. 4 — 6. Diagnosis : Real physa absent. The proximal part of the animal can, however, serve as a sort of physa when the cuticle is loosened. Scapus not polygonal, with a rather well-developed, easily deciduous cuticle. The ectoderm of the scapus with nematocysts mainly arranged in larger and smaller groups, its nemato- cysts 29 — 34 (37) X 7 — 8 11. Capitulum distinctly polygonal, the ridges however not as high as in M. loveni. Nematocysts of the capitular ectoderm 26 — 46 x 7 ^^, those of the tentacles partly 18 — 24 x 5 /i, partly 27 X 7 ,M. Number of tentacles from about 18 to 32. Nematocysts of the actinopharynx partly t3rpical, 17 — 20 X 3 /Jt, partly so, with distinct basal part to the spiral thread 22 — 29 X 5 //. lyongitudinal muscle-pen- nons weaker than in M. loveni; in the reproductive regions commonly with only 12 folds and never more than 20. Colour: Cuticle of the scapus brownish-yellow. "Physa" and scapus rose-red. Capitulum trans- lucent, flesh-coulored. Each capitular ridge has a fine Une of opaque white or hght pale-yellow with a dilute spot of the same colour near the base. Tentacles translucent, flesh-coloured, sometimes with alternate bands of stronger colour, often pale opaque-yellow at the base. This colour forms a spot on each side of the ten- tacles. Oral disc transparent with a cream-coloured star. Mouth as well as actinopharynx scarlet-red (Gosse) — Cuticle of the scapus dirtily yeUowish-brown. Capitulum, scapus and "physa" flesh-coloured, translucent. Capitulum has on the middle or a httle below a more or less opaque white annulus of rectan- gular spots, separated by a small flesh-coloured part from the pale whitish insertions of the mesenteries. These spots are sometimes prolongated as very pale lines on the rather strong capitular ridges, Tentacles flesh-coloured with a little tinge of rose-colour, especially conspicuous when the tentacles are contracted. The outer part of the oral disc is opaque white shading off into yellowish- white ; the colour also expands to the middle part of the tentacles as a narrow tongue-shaped spot with the point facing towards the end of the tentacles, and between the tentacles as narrow lines. The inner part of the oral disc is scarlet-red with opaque white streaks. Actinopharynx scarlet-red. Reproductive organs and filaments orange-coloured (Carlgren). Dimensions: Length of the column 2,5 cm., breadth 0,2 cm (Gosse). A small, expanded spec- ACTINIARIA 63 imen shows the following dimensions: Length of the column 1,5 cm, breadth 0,25 cm, length of the tentacles about 0,25 cm (Carlgren). Occurrence: Sweden, Bohuslan: Gullmarfiord. Flatholmen on the base of .^/cyom'MW-colonies (Carlgren), Smedjebrotten on stones overgrown with Sertularia (Carl- gren), Valbyfiord on the base of Alcyonium-colom&s (Aurivillius). Further distribution. S.W. Coast of England. Petit Tor and Orestone in the vicinity of Tor- quay. South Devon: Tenby South Wales, in the ebb-zone in cavities bored by Saxicava. Plymouth. Exterior aspect: The body is extended, almost cyhndrical and divisible into two regions, sea- pus and capitulum. Gosse states that a well developed physa is also present. I formerly (1892) adopted tliis opinion, mainly on basis of the description by Gosse. This so-called physa is, however, — as I after- wards have found out — to be interpreted otherwise, and the more so as also Gosse mentions that the most proximal part of it is sometimes furnished with a cuticle. If we more closely examine the iigure of Gosse (1856, PI. 9, figs. I, 4) which was to represent the animal with expanded physa, we find that the scapus- cuticle, above the cuticle-lacking most proximal part, forms some distinct, tranversal folds. The presence of these strong folds does not indicate a normal appearance of the proximal body-end, but is rather to be interpreted thus that the "physa" (the most proximal body-end) is not turned out, but the cuticle is in this part loosened and pushed upwards, whereby the above-mentioned folds are formed. The observations of these species, made by me during a long stay at the zoological station of Kristineberg, unmistakably prove this to be the case. The thing is that the animal very easily casts off its scapus-cuticle. This unfastening of the cuticle takes place most easily and frequently in the most proximal part which is mostly in con- tact with foreign bodies. A physa, at least in the proper sense of the word, therefore, to my mind, does not exist. Besides this, the proximal body-end may expand more or less disc-like when the animal has cast off the cuticle. The above-mentioned specimen altered its form during the time of observation in such a way that, instead of forming a prolongated cylinder, it formed a low cone with enlarged base, attached to the glass. The cuticle of the scapus is rugous, of ordinary- thickness and not incrusted. Also the distal part of the scapus-cuticle is loosely connected with the ectoderm of the scapus and forms an almost totally free tube into which the distal part of the animal can be drawn. Consequently the animal is able to contract much more than M. loveni. The capitulum is short, without a cuticle, distinctly polygonal and with 8 rather strong, longitudinal ridges which are, however, not as conspicuous as in M. loveni. The tentacles are 18 — 32 in number, the largest number observed by Gosse was 28, by Bourne 32, I have not found any more than 26 myself. According to Gosse the arrangement should be 8 + 8 + 12, in fact they are arranged hexa- merously as in M. loveni (6 -f- 6 etc.) in three or four cycles of which the fourth is verj- incomplete. The tentacles are short, the inner longer than the outer ones. The oral disc is small, with distinct radii. The mouth is placed on a high cone. The actinopharynx is short, with 8 longitudinal ridges and just as many longitudinal furrows. Whether a small ventral siphonoglyphe is present I cannot determine with certainty as the ex- amined specimens were not in every respect well presen-ed. Probably a siphonoglyphe is present here as in M. loveni. 64 ACTINIARIA Fig. 76. Fig. 77. Anatomical description: The ectoderm of the scapus is high, thicker than the mesogloea and contains nematocysts, 29 — 34 (37) X 7 — 8 /i in size, often somewhat curved, and large, very numerous gland-ceUs. The nematocysts are packed together in greater and smaller groups; there are, however, also a few nematocysts between the groups. The ectoderm of the capitulum is in the longitudinal ridges very high (textfig. 79) , a Uttle thicker than the mesogloea, but in the furrows thinner. In the ectoderm of the ridges there are numerous nematocysts, 26 — 46 ^ long and almost 7 fi broad, often a little curved, while the ecto- derm of the furrows does not contain any such. The mesogloea is thickened in the ridges. The ectoderm of the tentacles is provided with very numerous, smaller nema- tocysts (18 — 24 X 5 /i) and some few, a little larger (27 X 7 /i). The spirocysts are of variable size, the largest about 24 ji long. The ectoderm of the actino- / pharynx is high in the ridges as on the capitulum; in the furrows thinner and provided Pig yg with numerous, granulate M ilne-Edivardsia carnea.Vig. 76 gland-cells. Mainly in the rid- Transverse section through a portion of scapus in the repro- S^s typical nematocysts are ductive tract. Figs. 77—78- found (17— 20 X 3 //) and some Transverse sections of pennons in the reproductive tract. Fig. such with distinct basal part 79. Transverse section of a por- ^^ ^^^ -^^ ^-^^^^^ ^^^^ ^ ^^^1^ tion of the capitulum, n : ne- matocysts, me : mesentery. broader in the basal end (22 — 29x5,^. In the probably differentiated siphonogljrphe the gland-cells and spirocysts are few in numbers. The imperfect mesenteries in the most distal part of the body are considerably weaker than in M. loveni. The perfect, well-developed mesenteries are as usual in the Edwardsiidae 8 in number, in a spec- imen I have, however, found only 7 stronger mesenteries and 7 ridges in the actinopharynx (compare the similar discovery by lyevander in " Edwardsia carnea" = Paraedwardsia sarsii?). The folds of the longi- tudinal pennons are comparatively few in the reproductive region, ordinarily liigh and only a little rami- ficated, commonly 12 in number, sometimes many, but never more than 20. The lamellar outer part of the mesenteries issues not far from the outer edge of the pennons (textfigs. 77, 78). The parietal muscles (text- fig. 76) are in the capitular region very strong, in transverse-sections triangular or rather fan-shaped, they recall those of M. loveni, though they are not as richly folded ; in the reproductive region they are a Uttle weaker. Their expansion on the column is not considerable in the most distal part, in the reproductive organs they are a little more expanded, though only as far as to half their breadth. The ciliated streaks-are well developed, just as well as the intermediate streaks. The animal is dioecious. Biology : According to my observations this species as well as M. loveni are not sensitive to the ACTINIARIA (,^ effect of light. The animal when kept in an aquarium easily throws off its scapus-cuticle, and thereafter wanders about by means of its proximal end which thus becomes flattened, disc-like (compare above). It can besides attach itself by the sides of its body. The suckers which, according to Gosse, should be found in this species are, however, not present, neither are the " Halcampa-papillaQ" , characteristic of Paraedward- sia. The attachment wliich is, however, never firm, is performed exclusively by the secretion of the nume- rous gland-cells. The animal successively forms a new cuticle. On the biology of this animal Gosse (i860) tnoreover gives several informations. Remarks: Haddon (1889) has reproduced some figures of this species. The habitus-figure (PI. 33, fig. 15) represents a rather badly preserved specimen, the cuticle of which is for the greater part peeled off. Of the anatomical figures of the species only one, showing the parietal muscles, is of use to the identification which I can determine by a study of Haddon's sections. Though I have not been able to make more exact measurements of the stinging capsules I have, however, ascertained that the nematocysts of the scapus of Haddon's specimens were of the same appearance as those of the Swedish representative of the species, and arranged in groups. The Swedish form is also identical with the British one; on the other hand, the species which Appellof (1893) has described as E. caniea is a Paraedwardsia (compare P. sarsii). Gosse's figures of the species are rather good, especially the uncoloured ones. I have myself reproduced some figures of ana- tomical details, one of these is here once more reproduced. Milne-Edwardsia polaris n. sp. Diagnosis: The most proximal part of the body without cuticle, physa-like. Scapus with rather feebly developed cuticle, with comparatively few nematocysts (14—22 X 2, 5 — 3.5 11), arranged in groups winch sometimes are placed in shallow sinkings in the mesogloea. Capitulum polygonal. Its ectoderm with nematocysts, 14 — 17 fi long. Tentacles 12. The ectoderm of the tentacles with comparatively few spirocysts, 12 — 19 // long, and nematocysts, 15 — 22 X 2,5 jt in size. Nematocysts in the ectoderm of the actinopharynx numerous, 16 — 24 X 2, 5 — 3 fi. Longitudinal muscle-pennons of the mesenteries in transverse-sections through the upper part of the reproductive region with about 12 — 15 folds, branched in the outer parts of the pennons and sometimes also a little in the inner parts. The outer parts of the mesenteries issue not far from the outer side of the pennons. Parietal muscles somewhat feeble, with a few, sometimes rather thick folds. The parietal muscles are considerably expanded on the column. Colour: in alcohol: Scapus ochreous-yellow or dirtily-yellow. Dimensions in contracted state: length to about 1,5 cm, breadth to about 0,5 cm. Occurrence: East-Greenland. Fame Isl. Scoresby Sound 70°5o' N. 22°33' W. 5—8 m mud (Sw. Greenl.-Exp. 1899, N. 31, 2 sp.). East Spitzbergen King Charies I^and. Jena Isl. at N.E. Cape about half a league from land, in front of a great glacier. Coarse-grained, blue clay with a few, small stones. 36 m (Roemer & Schaudinn 1898, St. 31, i sp.). West-Spitzbergen, Ice-fiord, Temple bay, 43 — 45 m. Compact, greyish-red clay. 9 The Ingolf-Expeditimi. V. 9. 66 ACTINIARIA Fig. 81 Temp, at the bottom 2,5° (Sw. Spitzb.-Exp. 1908, St. 51, 2 sp.) Temple bay, Bio- na's haven, 30 m. Compact greyish-red clay with stones. Temp, at the bottom 3,78° (Sw. Spitzb.-Exp. 1908, St. 56, 2 sp.). Spitzbergen without distinct locality (Sw. Spitzb.-Exp. 1898). Exterior aspect: The physa, if present, is small, in as much as only the most proximal part of the column is devoid of a cuticle. On the scapus there are 8 shallow, longitudinal furrows, corresponding to the insertions of the mesenteries and particularlj^ distinct in the distal part. In contracted state of the animal the inV'Olved part of the scapus is polygonal. The cuticle of the scapus is, in comparison with the other Milne-Edward- sz«-species, feebly developed and some- times here and there lost. In the spec- imen collected by Roemer and Schau- dinn there are fragments of yellowish- \ brown particles and small grains of sand sticking to the undermost part of the sca- pus. I have not been able to observ^e any of the "//fl/c«w/)a-papillae" which exist in the genus Paraedwardsia, and therefore the gland-cells have probably served as organs of attachment. The capitulum is short, in the proximal part polygonal, in the distal part in transverse-sections more round. Pro- bably this difference is due to a various rig. So. Textfig. 80 — 82. Mitne-Edwardsia polaris. Fig. 80: Transverse section of a parietal muscle in the upper part of the glan dular tract. Fig. 81 : Transverse section of a pennon in the same tract. Fig. 82 Section of scapus -with groups of nematocysts (n). state of contraction of the different parts. The tentacles are not more than 12, on one specimen I observed tliat the two tentacles projecting from the ventro-lateral compartmetits are smaller than the others. The oral disc is inconsiderable, the actinopharynx is short and furnished with 8 longitudinal ridges at the in- sertions of the mesenteries; between the ridges there are deep longitudinal furrows. An indication of a ventral siphonoglyphe seems to be found (the specimens were, howe\-er, not so well preserved that I can state this with certainty). Anatomical description: The ectoderm of the scapus is now thin, now more thick, especially in the parts containing nematocysts. The cuticle is weak, especially in comparison with that of M. loveni and carnea. The nematocysts which in the scapus-ectoderm reach a size of (14) 17 — 22 X 2, 5 — 3 (3,5) n are here a little numerous and packed together in groups, scattered between the insertions of the mesen- teries and, on account of the thickening of the ectoderm, sometimes sunk a little down in the mesogloea (textfig. 82). The mesogloea is of about the same thickness as the ectoderm, the endoderm is however thin- ner. The high ectoderm of the capitulum contains nematocysts, 14 — 17 fi long, arranged on the ridges. In the parts of the involved cai)itulum which are the most closely pressed together the mesogloea forms high ridges ACTINIARIA 67 between the insertions of the mesenteries, in the other parts the mesogloea is more equally thick. The nema- tocysts of the tentacles reach a size of 15 — 22 X 2,5 jt, the spirocysts are about 12 — 19 11 long. The high ectoderm in the actinopharynx-ridges contains nematocysts, 16 — 24x2,5 — ^ fi in size. The mesogloea of the actinopharj'nx is thin, still a little thickened in the ridges. The longitudinal pennons of the mesenteries are rather well developed, with about 13 to 15 folds in tlie regions of the ciliated streaks and of the reproductive organs. The folds are in the inner and especi- ally in the outer parts very little ramificated and high, while in the middle of the pennorrs they are short and not branched (textfig. 81). The outer lamellar part of the mesenteries issues from the pennons rather close by the outside. The parietal muscles are not strong, with a few, short, broad folds, supported by thick- enings of the mesogloea; on the other hand they are considerably expanded on the column (textfig. 80). The filaments of the mesenteries were badly preser\'ed, so that I cannot give any information of their appear- ance. The animal is dioecious. Remarks: This species is rather interesting, as in some respects, concerning the arrangement of the nematocysts, it may be regarded as a previous stadium of the genus Edwardsia. If we imagine the nema- tocysts and their mother-cells in the colunm of M. polaris to be wholly enclosed in the mesogloea and the supporting cells reduced, we have a nemathybome. The genus Edwardsia cannot, however, directly descend from Milne-Edwardsia, because the arrangement of the tentacles in Edwardsia, compared with that of Milnc- Edwardsia, shows that both genera are developed, each in its own direction. Milne-Edwardsia nathorstii n. sp. Diagnosis: Proximal end rounded without distinct physa. Scapus with a well developed cuticle. Nematocysts of the scapus-ectoderm concentrated in small groups containing only some few capsules, 29 — 36 X 3,5 — 5 ti in size. Tentacles 12. Their ectoderm with very close spirocysts of variable size, the greatest spirocysts reach a size of 34 — 36 x 5 //. Nematocysts in the ectoderm of the tentacles not numerous, 31 — 36 X 3,5—5 //. Nematocysts of the actinopharynx 34—36 X 5 /i. lyongitudinal muscle-pennons of the mesen- teries in transverse-sections through the upper part of the reproductive region with some few, about 10, low folds, supplied with short, secondary folds. The lamellar outer parts of the mesenteries issue not far from the middle of the pennons. Parietal muscles not strong, with rather few folds, but they are consider- ably expanded on the column, where they have comparatively high folds. Colour in alcohol: Scapus dirtily-yellow. Dimensions in contracted state: Length of the column about i cm, breadth 0,15 cm. Occurrence: East-Greenland. Scoresby Sound, Hurry's Inlet, 7043' N. 22^29' W. 30 m mud (Sw. Greenl. Exp. 1899, N. 455, 456) 9 sp. N. of Spitzbergen 81^20' N. 20°3o' E. 1000 m (Roemer & Schaudinn, 189S, St. 41) I sp. Exterior aspect: As all specimens were contracted, with the distal part involved, and only of small size, I cannot give any complete information of the exterior of the species. The description is made after an examination of the specimens from Greenland. 68 ACTINIARIA Fig. 83. The proximal part is rounded and fusing into the middle without distinct outline. No distinct physa is present. The scapus is provided with a sometimes thin, sometimes thick, but translucent, often irregularly wrinkled cuticle, to the outside of which small grains and a great number of detritus-particles are attached. Under low magnifying powers small papilliform elevations are to be seen, which are, however, not regularly arranged, they are as yet only thickenings of the ectoderm as may easily be ascertained on sections (text- fig. 83). The capitulum is short, not thickened between the insertions of the mesenteries. The tentacles are 12 in number, probably arranged in two cycles; the oral disc is inconsiderable. The actinopharynx is short and furnished with 8 longitudinal ridges. Whether a ventral siphonoglyphe is present or not I cannot decide with certainty. -Anatomical descrip- tion: The scapus-ectoderm is as a nde not high, here and there it is, how- ever, thickened, cushion- like. In these thickenings the nematocysts are accu- mulated (textfig. 83 h). They are, however, not numerous, but the groups still must be regarded as weak batteries of nemato- cysts. The size of the ne- matocysts is 29 — 36 X 3,5 — 5 /I. The scapus is cove- red with a folded cuticle, now thin, now thick. If the cuticle (textfig. 83 c) is thick, it resembles the same layer in Isoedwardsia; it is only a little stained, or not at all so, with borax-carmine which is easily absorbed by the mesogloea. The mesogloea is tlrinner than the ectoderm. In the endoderm of the column I ha\'e observed large nematocysts. Whether these latter are normal com- ponents of the endoderm I cannot with certainty decide. The circular muscles of the column are weak. The ectoderm of the capitulum is tlucker than the mesogloea. The ectoderm of the tentacles is liigh and contains very numerous, closely packed spirocysts of variable size. The largest are of the same kind as those of the column, but more sparse and 34 — 36 x 3,5 — 5 // in size. The ectoderm of the actinopharynx is high in the ridges; the rather numerous nematocysts show a distinct basal part to the spiral thread and reach a size of 34—36 X 3,5— 5/-!- The immber of the mesenteries is 12 of which only 4 are weak off-shoots in the most distal part. The longitudinal muscle-pennons of the 8 "Edwardsia-mesentenes" are not strong in the reproductive region and show in transverse-sections about 10 low folds, all of about equal height or gradually shortened in the Fig- 85- Textfigs. 83 — 85. Milne-Edwaydsia nathorstii. Fig. 83: Transverse Sectiou of a portion of the scapus (compare text!). Fig. 84: Transverse section of a perfect mesentery in the reproductive tract. Fig. 85 : Transverse section of parietal muscle. ACTINIARIA 69 inner parts, and provided with secondary branches. The lamellar part of the mesenteries issues from about the middle of the pennon (textfig. 84). The endoderm of the pennons is high between the actinophar>'nx and the reproductive region, with numerous vacuoles on the side where the folds are ; on the opposite side, however, it has no such vacuoles, but denselj^ packed nuclei. The parietal muscles (textfig. 85) expand rather far on the column in the reproductive region and still farther in the distal end of the column (textfig. 85). The filaments are of usual appearance, the cihated streaks short. The animal is dioecious. One examined species was a male, another a female. The nematocysts in the ectoderm of the scapus of the specimen, taken by Roemer and Schaudinn, were a little smaller (24 — 27 x 3,5 — 4,5 ji) than those of the type-specimens. As far as I can see from the structure of the badly preserved specimen it belongs to M. nathorstii. The lon- gitudinal pennons and the parietal muscles are of the same appearance as those of the type. Genus Paraedwardsia Carlgr. Diagnosis: Milne-Edwardsiinae with no physa or only a weakly developed one. Scapus with a more or less well developed cuticle and with scattered "i/a/ca;w/>fl-papillae". Nematocysts of the scapus- ectoderm scattered, with a tendency to arrange themselves in groups; they are comparatively broad, in pro- portion to their length. Nematocysts of the scapus and of the capitulum of about the same size. Inner ten- tacles longer than the outer ones, now hexamerously, now octomerously(?) arranged. A weak ventral sipho- noglyphe present (always?). This genus which was characterized by myself in a few words in 1905 is distinguished from the nearly related Milne-Edwardsia by having on the scapus "//^a/cam/)a-papillae" which are absent in Milne-Edwardsia. Concerning the structure of these papillae, also occurring in other Actiniaria-genera, I refer to the genus Halcampa. Whether the tentacles always are arranged hexamerously I cannot confirm. In the type P. arc- naria the number of the tentacles appears to be 16, but whether they are arranged 6 + 6 + 4 or 8 + 8 is difficult to decide as the state of preservation of the tentacles was not good. Probably the tentacles of this species are distributed according to the latter type. It also remains to verify the presence of a ventral sipho- noglyphe in tliis species. P. sarsii (Diib. & Koren) belongs to this genus besidt^s the type P. arenaria Carlgr. Paraedwardsia arenaria Carlgr. PI. I. Fig. 15, 16. Paraedwardsia arenaria n. sp. Carlgren in Nordgaard 1905, p. 158. Diagnosis: No distinct physa. The most proximal part of the body, however, probably without "i/fl/cam/)a-papillae. Scapus with a somewhat thick cuticle? (periderm) and with scattered "//fl/cawj^a-papillae" to which grains of sand are attached. Ectoderm of the scapus with scattered nematocysts partly 17 — 22 X 3 /i, partly 26 — 29 X 4 n. Nematocysts in the capitular ectoderm partly 14 X 2 [i, partly about 24 X 2,5 fi. Capitulum and scapus in preser\'ed state with 8 indistinct longitudinal furrows. Tentacles 16, prob- ably in two cycles. Nematocysts of the tentacles about 24 X 2 ji, spirocysts to about 28 — 40 /i long. Nema- tocysts of the actinopharjmx partly 20 — 22 X 2 ,1, partly 31—36 X z t^- Longitudinal muscle-pennons of yQ ACTINIARIA the mesenteries in transverse-sections rather elongated with about 25 — 30, somewhat richly ramificated folds in the inner and especially in the outer parts. Inner folds of about equal height, considerably lower than the outer folds. Lamellar outer parts of the mesenteries attached to the outer part of the pennons. Parietal muscles well developed, recalling two fans, one on each side of the main-lamella of the mesogloea. The expansion of the parietal muscles on the column the ordinary one. Colour in preserved state: the specimens from the Gunhild-Expedition and from Skierstad have an ochreous-yellow scapus with deep black, in the proximal part very numerous grains, which are so densely packed that they almost completely cover the yellow periderm. The scapus of the Bergen-specimen is dirtily- ochreous-yellow ; the capitulum and the tentacles are slate-gray. Dimensions in preserved state: i) One Gunhild-specimen (PI. i, fig. 15). I^ength 3,6 cm, largest breadth 0,5 cm. The other Gunhild-specimen: I^ength 3,3 cm, largest breadth 0,8 cm. Bergen-specimen i: Length almost 3 cm, largest breadth, a little above the proximal end, 0,5 cm. Length of the tentacles in expanded, preserved state 0,3 — 0,35 cm. Bergen-specimen 2: Length almost 2 cm, largest breadth 0,3 cm. Occurrence: Norway. Finmarken. Skierstadfiord 330 m (Nordgaard 1900 2 sp.). Herlofiord 130 fms. (Appellof 2sp.), 9 miles N. of Jaderen 140 fms (G. O. Sars i sp.). Skagerrak 370 fms. clay (Gunhild-Expdition 1879, St. 10, 2 sp.). Exterior aspect: A distinct physa seems to be absent. True enough the proximal end is a little different in appearance from the other part of the scapus, but the presence of fragments of a periderm in the most proximal part (PI. i, fig. 16) of a Gunhild-specimen indicates that we not have to do with such a regular physa as that of the genus Edwardsia. The periderm of the most proximal part of the body seems, however, to be very easily dropped, and the "//a/caw^a-papillae" are probably absent, or at least so sparse that this part appears as having no papillae. A distinct boundary line between the most proximal part and the other part of the scapus is, however, not to be seen. Excepting the most distal part of the scapus, where the papillae are sparse, these latter are found in great numbers on the other part of the scapus (PI. i, fig. 15). To the papillae numerous grains of sand are attached, as in Hakampa. Besides this the scapus is covered with a yellowish, rather thin periderm, possibly formed only by a stiffened product of the secretion of the gland-cells. Whether there is a regular cuticle I cannot with certainty decide, I have therefore used the vaguer term of periderm here. The capitulum is short, smooth, without a cuticle and with translucent in- sertions of the mesenteries. In the contracted state of the animal, longitudinal furrows, corresponding to these insertions, are visible in the capitular region, as well as in the i)roximal part of the body. The number of tentacles is 16, probably arranged 8 + 8. They are rather long and conical. Whether the inner tentacles are longer than the outer ones I cannot with certainty decide, but it is possible that it is so. Tlie difference between the sizes of the tentacles in the two cycles is, at any rate, inconsiderable. The oral disc is small, the actinopharynx short and furnished with longitudinal furrows. Whether a ventral siphonoglyphe is pre- sent is doubtful, the sectioned specimens were not well preserved, as regards the actinopharynx. Anatomical descriptions : The most proximal part of the body is provided with a high ectoderm, containing numerous gland-cells and nematocysts, partly smaller, about 17 — 19 /i, partly larger, about 24 — 26 fi. The ectoderm of the scapus is rather high, with numerous, scattered, typical nematocysts, partly ACTINIARIA 71 smaller, 17—22 X 3 //, partly larger, 26 — 29 X 4/1. In the papillae which show the same structure as those of Halcampa, the ectoderm is low, and the cells of another structure than that of the other parts (compare the family Halcanipidae) . The scapus hardly seems to form a regular cuticle, l)ut by the secretion of the gland- cells particles of mud and foreign bodies are glued together so as to form a thin membrane, covering he scapus (compare above!). The mesogloea is stratified, of ordinary thickness and sometimes tapering into papilliform off -shoots. When the scapus is expanded the "//rt/c(?m/)fl-papillae" are not distinct, and their position is only indicated by their structure which is different from that of the other parts of the scapus. The scapus-endoderm is of about the same thickness as that of the ectoderm. The capitular ectoderm, is high, higher than the mesogloea and contains numerous nematocysts, partly larger 24 X 2,5 fi, partlj- smaller aliout 14 X 2 fi. On maceration-preparations of the capitulum I have also observed spirocysts. As, however, I did not find any spirocysts on sections through the same region, it is probable that the spirocysts belonged to the tentacles, and were stuck to the capitulum which is invaginated with the tentacles. The mesogloea of the capitu- lum is more fully developed in the middle of the compartments than on their sides. The ectoderm of the tentacles contains numerous nematocysts, 24 n long and 2 n broad, and ven,- numerous spirocysts of a length of unto 28 — 40 [i. The high ecto- derm of the actinopharynx is furnished with numerous nematocysts, partly larger, about 31 — 36 X 3 ft, partly smaller, 20 — 22 x 2 n. The 8 imperfect mesenteries are short and thick. The longitudinal muscle-pen- nons on the 8 perfect "Edwardsia mesenteries" appear rather elongated on trans- verse-sections in the reproductive region (textfig. 86) and with about 25 to 30 folds. These latter are rather much ramificated, especially in the outer parts. The more cen- tral folds are of almost equal height and considerably lower than the folds nearer to the outside. In the region of the ciliated streaks and off the actinopharynx the folds are lower and more concentrated. The parietal muscles are well developed (textfig. 86) '^^^ ^^'^^'-rfZlIZ^l^ '■ arenaria. transverse sec- with several folds of fan-shaped appearance on each side of the main-lamella of tion of me.sentery. the mesogloea. The parietal muscles are rather considerably expanded on the column, but they do not reach as far as the parietal muscle-pennons extend. The ciliated streaks, the streaks between these lat- ter, and the middle streak are well developed. In the lower parts of the filaments there are also boundary streaks, furnished with vacuoles along their outside. The animal is dioecious. Two specimens, examined more in detail, were males (Textfig. 86 te: testes). The anatomical description of this species is principally based on the specimens from the Gunhild- Expedition. Paraedwardsia sarsii (Diib. & Koren) Carlgr. PI. I. Figs. 8. 9. PI. 4. Fig. 7. }Lecythia brevicornis n. sp. M. Sars 1829, p. 27, PI. i, fig. 10. ? — — Sars, Sars 1833, p. 226, PI. 10, fig. 5, 1835, p. 3, Khrenberg 1834, p. 72,. Edwardsia sarsii Diib. Diiben and Koren 1847, p. 267. y2 ACTINIARIA Edwardsiella sarsii Sars, Andres 1883, p. loi. }Edwardsia carnea Gosse, Ivcvander 1892, p. 292, fig. Edwardsia carnea Gosse, Appellof 1893, p. 4, PI. i, PI. 2, figs. 6—9, PI. 3, figs. 12—18, 20—23, 1895. p. 7, II. Grieg 1897, p. 4, 9. 12. Milne-Edwardsia carnea Grieg 1913, p. 143. Diagnosis: A small, not vesicular, physa present. Scapus-circumference round, with distinct longitudinal furrows, but with a thin periderm, scattered "/fn'/c«w/)a -papillae" and scattered nematocysts partly 17 — 22 X 3,5- — 4,5 ji, partly 8 — 12 // long. Capitulum polygonal with 8 rather distinct longitudinal ridges and with nematocysts partly smaller, 10 — 14 X 1,5 — 2 ji, partly larger, about 24/^ in size. Tentacles from 20 to more than 30, the inner ones longer than the outer ones and hexamerously arranged, with nema- tocysts 19 — 22 X 2 /i and spirocysts to about ^28 X 5 /i in size, in the ectoderm. Typical nematocysts in the ectoderm of the actinopharynx partly 14 — 22 X 1,5 — 2//, partly 24 — 29 X 2,5 — 3,5 /i, besides nemato- cysts with distinct basal part to the spiral thread 22 — 24 X 3,5 — 5 fi in size. A hardly differentiated ventral siphonoglyphe. Nematocysts in the endoderm of the column, tentacles, and actinopharynx numerous, 34 — 43 X 5 //. Longitudinal pennons of the mesenteries in the reproductive regions on transverse-sections rather elongated with about 15 — 20 somewhat ramificated folds. Inner folds of rather equal height, con- siderably lower than the outer folds. The lamellar part of the mesenteries attached to the outer part of the pennons. Parietal muscles in the reproductive region well developed, rather richly ramificated and on trans- verse-sections of a rounded appearance, in the other parts considerably weaker and arranged more in the shape of a fan. The parietal muscles are considerably expanded on the column. Colour; Physa uncoloured. Scapus brownish-yellow. Capitulum and tentacles translucent, un- coloured. Oral disc and actinopharynx red (Appellof 1893). According to Sars (1829) the colour of his Lecythia brevicornis was: Scapus dirtily-green, opaque. Capitulum and tentacles hyaline, shading off into pale red. Mouth and actinopharynx dark red. Dimensions : Length to 3,5cm, breadth 0,3cm (Appellof). Length of Lecythia about 0,8cm (Sars). Occurrence: Norway. Bergen on Saxicava pholadis [Lecythia M. Sars) Bergen, Manger (M. Sars, Schaudinn). Radofiord N. of Bergen, Alvarstrommen Bergen 30 — 40 fms. sand and mud (Appellof). Hardanger fiord. Straumastein 100 — 200 m, Eikevik 50 — 150 m (teste Grieg). Herlofiord, Dalstobugten 6 — 12 fms. mud (Appellof). Ulvesund Lestholmen, Skarebugten 60 — 100 m shelly sand mixed with clay (teste Grieg). Vaagsfiord Holnaesviken 40 —100 fms. sand (teste Grieg). Vaagsfiord, Southern point of Skavoen to Tomberviken (teste Grieg). Korshavn (G. O. Sars). Exterior aspect: The most proximal part of the animal is modified into a small, not ampulla- ceous, physa which is commonly involved, according to the statement of Appellof. The scapus is on trans- verse-sections rounded, without longitudinal furrows, but with a thin periderm which is sometimes a little wrinkled on preserved specimens, on account of the contraction of the column. If the arumal is wholly ex- panded the insertions of the mesenteries are visible (according to Appellof). This author declares that the ACTINIARIA 73 scapus is quite smooth. The scapus is in fact provided with scattered "//a/ca;«/)a-papillae" to which small grains are sometimes attached in the proximal parts of the scapus (textfig. 87, PI. i, figs. 8, 9). The capitulum is polygonal and has 8 rather elevated longitudinal ridges between the insertions of the mesenteries. The tentacles of Lecytkia are (according to Sars) 20, 25 — 26 in number, those of carnea, according to Appellof, some 20 to some 30. I have observed 24 — 28 tentacles myself. The inner tentacles are longer than the outer ones, all short and of about the length of the capitulum, conical and hexamerously arranged in at least 3 cycles. Appellof says that there are only 2 cycles of tentacles present. The oral disc is inconsiderable. The actino- pharynx is short, with 8 longitudinal furrows and the same number of longitudinal ridges. A feebly developed ventral siphonoglyphe seems to be present. Anatomical description : The pln-sa is devoid of a periderm. The ectoderm contahis numerous nematocysts, 8 — 15 ,« long. The scapus-ectoderm is high and covered with a thin periderm. Its nematocysts are numerous and of two dimensions, partly comparatively broad 17 — 22 X 3,5 — 4//, partly smaller, thin- ner and about 8 — 12 /i long. The mesogloea is of about the thickness of the ectoderm or thinner and almost homogeneous. The endoderm is a Uttle lower than the ectoderm and contains numerous nemato- cysts (text fig. 89, 92 n), 34 — 38 X 5 n in size and often a httle cur- ved; these endodermal nematocysts make a characteristic feature of this species. I have obsers-ed such capsules also in the endoderm of the tentacles and of the actinopharjaix. (Their size is 36 — 43 X 5 /^). The capitular ectoderm is high and provided with nematocysts which are smaller in the proximal parts (10— 14/; long), in the distal part, .„„,,. ... , ^ ^ Iig. 87. Paraedwardsia sarsn. Arrangement on the other hand, unto twice that length. In the furrows they are of the "Ha/cam/>a-papillae" between two ,. , 11 -r .1 mesenteries, pm: parietal muscles, sparse, on the ridges numerous. According to Appellof there are nerv^e-cells and ner\^e-fibrillae in the capitular ectoderm. The capitular ridges arise from the thickenings of the mesogloea. The ectoderm of the tentacles contains rather sparse nematocysts, 19—22 X 2 /^ in size, and numerous spirocysts unto 28 X 5 // in size. The ectoderm of the actinopharynx is high with scattered typical nematocysts partly smaller 14—22 X 1,5—2//, partly larger, 24—29 X 2,5—3,5//. Besides these, there are also nematocysts with distinct basal part to the spiral thread and somewhat broad in the basal end. Their size is 22—24 X 3,5—5 //• The ectoderni of the siphonoglyphe is only a Uttle differentiated from the other ectoderm of the actinopharynx, but it is provided with longer ciha than this part. Appellof has not found any differentiation of the actinophar>'nx. The weak imperfect mesenteries in the most distal part are rather well developed. The longitudinal muscle-pennons of the 8 perfect "Erfi^arrfsw-mesenteries" are in the reproductive region provided with 15 —20 folds (textfig. 88) which are a Httle raraificated, mainly in the outer part. The inner folds of the pen- non are considerably lower than the outer ones, and the pennon itself, on transverse-sections, rather elon- gated in the reproductive region (textfig. 88). The lamellar outer part? of the mesenteries are attached to the pennon in its outer part. In the endoderm of the mesenteries large nematocysts of the same structure 10 Tlie Ingolf-Expedilion. V. 9. 74 ACTINIARIA as those in the endoderm of the cohimn here and there occur. Tlie parietal muscles' are in the reproduc- tive region strong with numerous folds and on transverse-sections of a rounded appearance (textfig. 92), in the capitular tract considerably weaker and arranged more or less in the shape of a fan (textfig. 90, 91). The part of the parietal muscles which expands on the co- lumn is considerable and as broad as the parietal muscle-pennon itself. The mesenterial jSlaments have a typical appearance. The animal is dioecious. Biology : The animal lives unattached, mainly on sand (Appellof) or on sto- nes, or attached to shells? {Lecythia according to Sars). Remarks : Whether Sars's Lecythia brevicornis is identical with Appellof's Edwardsia carnea is very dif- ficult to decide ; on the other hand the species described by Appellof is the same species as Edwardsia Sarsii Diib. & Koren, which I have been able to substantiate on specimens belonging to the Museum of Christiania and labelled "Ed- wardsia sarsii Diib. & Koren, Bergen, Manger, Sars". As to Lecythia it is possible that Sars's description alludes to the species later on described by Gosse as Edwardsia car- nea ; in reality S ars's figure and description of this species and its occurrence on Saxicava more recall Edwardsia carnea Gosse than Paraedwardsia carnea (Diib. & Koren). As it is, however, hardly possible to decide these 1 Appellof (1891, p. 21) states that the parieto-basilar muscles are absent in E. carnea. This is certainly not the ca.se as the part of the parietal muscles ou the opposite side of the pennons corresponds to the parieto-basilar muscle (com- pare Carlgren iyo5, p. 5i7_5i8). Textfig. 88 — 92. Paraedwardsia sarsii. Fig. 88: Transverse section of pennon in the reproductive tract. Fig. 89: Transverse section of a mesentery in the uppermost part of the cnido-glandular tract (in the capitular region). Fig. 90 — 92: Transverse section of parietal muscles in the capitular region (figs. 90, 91) and in the reproductive tract (fig. 92). ACTINIARIA 75 questions without examining Sars's type-specimen, if it exists, it may be more suitable totally to disregard the genus Lecythia, the more so as any diagnosis of the genus never was given by Sars. There, is, however, no doubt that Lecythia is identical with one or other of the genera Milne-Edwardsia and Paraedwardsia, proposed by myself. Of the latter genus I have had an opportunity of examining the specimens determ- ined as Edwardsia sarsii, further the specimens in the Museum of Berhn (Schaudinn's sp.), those from Korshavn and Appellof's specimens. Appellof {1893) has given a description of the outer as well as the inner organisation of the species; on several points his description is completed here, especially as regards the nematocysts — Appellof does not mention any nematocysts in the capitulum or in the ectoderm of the tentacles — and the occurrence of the "//aZc«w/)fl-papillae" which are also overlooked by Appellof; I made the section-series from the specimens from Bergen, Manger, from Appellof's specimens, and from those from Korshavn. The text-figures, reproduced here, refer to the first-mentioned ones. Fam. Linmactiniidae nov. fam. Diagnosis: Athenaria without tentacles or spluncter. Perfect mesenteries 8 — 10 (or more?). Concerning the position of the fanuly and the reduction of the tentacles see my remarks to Limnac- tinia Icavis. Genii.s Limnactinia nov. gen. Diagnosis: Limnactiniidae with the column not divisible into regions. Column smooth, without cuticle or "//fl/c«w/)fl-papillae." Proximal body-end rounded as a physa, perforated by apertures. Ectoderm af the oral disc very thickened, containing numerous spirocysts. Distal part of the column with spirocysts. No siphonoglyphes. Perfect mesenteries 8 to 10 with reproductive organs. Rather few imperfect mesenteries. Of this genus I know two species, Limnactinia laevis, described below, and another one dredged by the Swedish Antarctic-Expedition at South Georgia. Limnactinia laevis nov. sp. PI. I. Figs. 13, 14. nov. sp. Carlgren 1893, p. 23, Note. Diagnosis: Proximal body-end with a central aperture surrounded by a cycle of 8 (-10?) apertures. Nematocysts in the proximal part of the column partly 14—18 fi long, partly 24 X 4 «, in the distal part II— 14// in size. Spirocysts of the column 16— 20 // long. The most distal part of the column with a weak longitudinal muscle-layer. Ectoderm of the oral disc extraordinarily high with very numerous spirocysts, ig—^(,[i long, and very sparse nematocysts, 11— 14/.! long. Ectoderm of the actinophar>'nx with nemato- cysts 24—26 X 4 fi in size. 8 "Edwardsia-mesenteries" or 10 (8 + 2 dorsolateral) mesenteries perfect; the two ventrolateral mesenteries of the first cycle always imperfect. 2 (dorsal) to 4 (dorsal and lateral) mesen- teries of the second cycle present. Longitudinal muscle-pennons of the perfect mesenteries in the repro- ductive region with 9 — 15 high folds, branched mainly in their outer parts. Outer lamellar part of the mesen- teries attached close by the outer edge of the pennons. Parietal muscle with a few, thick folds. The expan- 76 ACTINIARIA siou of the parietal muscles on the column is considerable. Several marginal stomata. Ciliated streaks dis- continuous. Colour: opaque white to yellowish- white with dirtily-yellow reproductive organs and filaments. In the distal part of a contracted specimen I obser\'ed brownish spots, discernible from the surface. Probably they belong to the uppermost part of the colunm or to the oral disc. Dimensions: Two specimens from GuUmar fiord were 2,7 resp. 2 cm in length, and 0,2 in breadth. The length of the specimen from Kal fiord was 1,3 cm, its largest breadth 0,3 cm. Occurrence: Sweden. Bohuslan. Gullmar fiord, Skar, lyindholm, between L,ysekil and Kristine- berg 30 — 70 fms. clay (Carlgren 1893) 5 sp. Norway. Finmark. Kal fiord 80 m. clay (Goes and Malmgren 1861). Exterior aspect: The body (PI. i, figs. 13, 14) is elongated and quite smooth, without a cuticle and provided with shallow, though distinct, longitudinal furrows corresponding to the insertions of the mesenteries. It is not divisible into regions. The proximal part is ampullaceous or pointed, according to the state of contraction. In the centre of this part there is an aperture surrounded by a cycle of apertures arranged as those oi Halcampa (Carlgren 1893, textfig. 7). In one examined specimen the cjxle contains 8 apertures, one in each " Edwardsia-compsLttment." It is possible that the number of apertures is 10, if 10 mesenteries are perfect. As far as I can see there are no tentacles. The animals having been dredged in deep water were not in full vigour in the aquaria. I have, therefore, only once observed a wholly expanded specimen. In this one I was not able to find any tentacles. Two other specimens were examined under strong magnifying power with the same results. I at first supposed that the tentacles were invaginated, as it is often the case in Hal- campoides, or that they had been thrown off as in Bolocera, but soon discovered that there was notliing in the organization to support that supposition. The study of two serial sections, of which one is complete, likewise proved that there are no tentacles. The structure of the oral disc also indicates that the distal end of the animal is transformed. The oral disc is namely very much thickened and forms a high wall, provided with radial furrows, corresponding to the insertions of the mesenteries. The actinopharynx is short, in comparison with the length of the body. It is devoid of siphonoglyphes, gonidial tubercles and aboral prolongations. Anatomical description: For anatomical examination I have sectioned series of two whole specimens. Of two others one has been transversely sectioned in the proximal part, the other one in the distal part. The specimen from Kal fiord I have sectioned longitudinally in the distal part, transversely in the tract of the actinophar>'nx and below the actinopharynx. The wall of apertures in the proximal body-end is in structure similar to that of the Halcampa (Carl- gren 1893 a). The three layers of the column are all of about the same thickness; in the distal part the ecto- derm is, however, thicker than the other layers. In the ectoderm of the column the two common types of stinging capsules are found, in addition to large homogeneous, and smaller granulate gland-cells. The nema- tocysts are in the proximal part rather numerous and about 14 — 18 // long, in the distal part a little more sparse and shorter (11 — 14 n) ; the spirocysts, on the other hand, reaching to a length of about 16 — 20 ii are numerous in the distal part, in the proximal part very sparse, only here and there appearing. In the ecto- derm of the column I have besides found somewhat larger nematocysts (24 x 4 //), sometimes with a distinct ACTINIARIA 77 basal part to the spiral thread. The uppermost part of the column is provided with distinct, though weak longitudinal muscles, forming a continuous layer in the tract where the spirocysts are common, but soon disappearing. A nerve-layer with nerve-cells is present and is the most developed in the uppermost part of the column. The mesogloea of the column is composed of alternate layers of longitudinal and circular fibrillae. The endodermal circular muscles form no special sphincter, but are rather well developed; in the proximal part, close by the proximal end, they are a little stronger than in the other parts. Tlie nmscle-folds are besides of different appearance, according to the state of contraction. The tract, corresponding to the region of the tentacles and the oral disc in other Actiniaria, is provided witli a remarkably Irigh ectoderm, several times higher than that of the column. The outer parts of this ectoderm consists, as a transverse-section through the oral disc shows (textfig. 93), almost exclusively of extraordinarily numerous, \'ery closely packed spirocysts, 19 — 36 /.< long; only exceptionally nematocysts appear, 11 — 14// long. The inner parts of the ectoderm are verj' deeply stained with the carmine of borax. Here we see the mother- ;)^S||^ j>«i*-"i^ cells of the spirocysts, and spirocysts in development. The ner\-e-layer is not ver>' distinct, on account of the immense number of stinging capsules. The radial muscles of the oral disc are weak and its mesogloea thin. The ectoderm of the actinopharynx is several times thicker than the mesogloea, here and there sending out irregularly pla- ced tongues towards the lumen of the actinopharynx. The nematocysts of the actinopharynx ectoderm are broader in the basal end than in the distal one, and the basal part to the spiral thread is perceptible; their size is about 24 — 26x4 [i. Also in the actinophar>'nx there are longitudinal muscles, though weak, but distinct, especially in the aboralpart. The actinopharynx is provided Textfig. 93. Umnachma laevis. Transverse section with several longitudinal ridges and furrows. I have not observ^ed any siphonoglyphe. of oval disc. The mesenteries are partly perfect with longitudinal pennons, reproductive organs and filaments, partly imperfect without such organs. The number of perfect mesenteries variates from 8 to 10. In three examined specimens only the 8 " Edwardsia-m&sentmes" were perfect (textfig. 94 — 95); in two larger spec- imens, provided with well developed reproductive organs, also the fifth couple was perfect (textfig. 96) ; thus the number and the arrangement of the mesenteries were in conformity witli those of Pentactinia (Carl- gren 1900). Four (2 dorsolateral and 2 ventrolateral) or two (ventrolateral) imperfect mesenteries together with the 8 resp. 10 perfect " Edwardsia-m&sent&nes" form the first cycle of six pairs of mesenteries. An im- perfect second cycle of weak mesenteries, not projecting over the surface of the endoderm, is present. In one specimen only two pairs of mesenteries, one in each dorsolateral exocoel, were developed ; in the other specimens there were 4 pairs in the dorsolateral and the lateral exocoels. In the ventrolateral exocoels I have never found any mesenteries. The arrangement of the muscles is the same as in other elongated Athenaria. The longitudinal pennons are strong, the high folds, howe\-er, rather few, in the upper part of the repro- ductive region about 9 — 15; they are mainly branched in their outer parts. The parietal muscles as well as the nmscles of the imperfect mesenteries are provided with short and coarse folds. The expansion of tlie parietal muscles on the colunm is considerable and often extends far sideways from the folds of the parietal muscles. Below the pennons the parietal muscles are as usual more elongated, form no folds and are attached 78 ACTINIARIA Fig. 99. Textfigs. 94 — loi. Limnactinia lacvis. Fig. 94. Transverse section of a specimen with 8 perfect mesenteries in the upper part of the actinopharynx. — Fig. 95. A similar section of the same specimen in the lower part of the actinophar3'nx. — Fig. 96. Transverse section of a specimen with 10 perfect mesenteries. — Figs. 97 — loi. Trans- verse sections of a mesentery in the reproductive tract. If we indicate the first section (fig. 97) withi, the following sections are the foiu-th, the eighth, the sixteenth and the twentv-third. to the mesogloea as an even lamella. The fifth couple \-iz. the ventral mesenteries of the dorsolateral pairs, project as imperfect mesenteries a little over the surface of the endoderm; in this state they carry very undeveloped filaments, but no reproductive organs, figs. 94, 95. The mesenteries of the sixth couple, viz. the ventral mesenteries of the ^'entrolateral pairs, are always very weak and only a little stronger than the mesenteries of the second cj'cle. The ten stronger mesenteries are provided with stomata. As in Scytophorus antardicus there are several stomata distally placed in each perfect mesenterj-, the}' do, however, seem to be less numerous (unto ACTINIARIA 79 4 in each mesentery). Commonly they are found in the middle or in the outer rim of the mesenteries. In the section reproduced in the textfigure 96 the stomata have been liit, and the mesenteries thus disconti- nued. The filaments appear only on the 8 to 10 perfect mesenteries. The ciliated streaks are very long, but discontinuous as in Scytophorus antarcticus and I soedwardsia mediterranea, and thus divisible into several por- tions along the middle streak. The textfigure 97 shows a transverse-section through a mesentery with a testes follicle and a rather well developed middle streak; a little farther down, towards the proximal end, we find rather well developed ciliated streaks (textfig. 98) which are still more distinctly seen on the following transverse-section (textfig. 99). In a transverse-section stiU farther down (textfig. 100) we meet several testes follicles, but only a rather inconsiderable middle streak. In the following sections we again find the middle streak (textfig. loi). The filaments are, as for the rest, of usual structure, and the cnido- glandular tract thicker than the middle streak. Three examined specimens were males, a fourth one a female. The reproductive organs were well developed, especially in the specimens with 10 perfect mesenteries. Biology: The animal lives on clay bottom, and on account of its particular structure it might very weU ha\-e the habits of a worm. Probably it pushes deep down into the clay, for it is worth noticing that I have observed the animal only one summer when we used a deep-going dredge, constructed by Professor Tulll^erg, at the zoological station of Kristineberg, and never during the many others summers I spent at the station. With its proximal end it is able to penetrate into the clay as the Edwardsids and Hal- campids; but also the distal end possibly .ser\^es as a boring organ. As the tentacles are wanting, the animal must take its food in another way than the other Actiniaria, it is therefore possible that it feeds upon detri- tus-particles in the clay, though I have not found any such in its coelenteric cavity. It is besides reasonable to suppose that the .strongly tliickened oral disc with its numerous spirocysts ("Klebkapseln") has under- taken the function of the tentacles as capturing apparatus. The occurrence of a really tentacle-lacking Actiniaria is thus established. True enough, R. Hert- wig (1882, 1888) has believed himself to have discovered forms, among the Actiniaria from the Challenger Expedition, which were tentacle-lacking or with ver>' reduced tentacles, but these observations have appear- ed not to be correct. The tentacle-lacking Actiniaria, described by R. Hertwig, are namely to be referred to forms having thrown off their tentacles (Mc. Murrich 1893, Carlgren 1899), and those with strongly reduced tentacles, provided with large stomidia, to forms, the state of preservation of wliich leaves a great deal to be desired. (Compare Sicyonh crassa). In the cases where the bad preservation of the animals has made it impossible to perform a control-examination we may resort to a similar kind of explanation. In some cases recorded by Hertwig — as far as I remember especially of Polyopis — it is possible that the tentacles were invaginated before they were macerated. In the genus Halcampoides it namely often happens that some tentacles, rarely all, become invaginated on preservation. In the latter case, when aU tentacles are invaginated, it looks as if they are wanting, and only large stomidia remaining. Ver>- smaU tentacles we find in some Discosomids, especially in Discosoma Unguja. Here the tentacles, arranged in radial rows, do not reach the surface of the oral disc, but are indicated by invaginations in the mesogloea of the oral disc. Systematic remarks. I have placed this family among the Athenaria because of the structure of its proximal end and of that of its mesenteries. The presence of ectodermal muscles and of spirocysts in So ACTINIARIA the uppermost part of the column would possibly make tliis species entitled to a position among the Pro- tactininae, but as a similar distribution of the ectodermal muscles and the spirocysts also occurs in the genus Hakamfa, though these organs do not reach as far down in the latter species as in Limnactinid laevis, I think that we may, at least provisionally, place it with the Athenaria. It is, besides, possible that the pre- sence of the ectodermal muscles in the column is a secondary feature arisen in connection with the manner of living of the animal. In the second species of the genus I have not found any ectodermal muscles in the colunm, but only spirocysts. Fam. Halcampoididae. Diagnosis: Athenaria (Abasilaria) generally with elongated body and with proximal body-end physa-shaped or flattened. No sphincter or a very weak endodermal one. Tentacles always present, com- monly with more than 8 perfect mesenteries (in SynhalcampcUa^ only the "Edwardsia-xwesentQries" per- fect). No acontia. Ciliated streaks present, rarely discontinuous. To this family which is identical with the Halcampomoriihidae, proposed by myself, I refer, as above mentioned (p. 21), Halcampoides T> an., A cthelmis lyiitk., Phytocoetes Ann. and Halcampella Andr., the last genus under the supposition that the type, as yet not examined in detail, fl^.^riwwi^ato Andr., has no mesogloeal sphincter^; further Scytophorus R. Hertw., Pentactinia Carlgr., Harenactis Torrey, Siphonactinopsis Carlgr., Mesacmaca Andres (the last genus under the same supposition as Halcampella). Peachia Gosse, Eloaciis Andres, HaloclavaYetTill, and finally also Polyopis R. Hertw. may be placed to this family (compare below). I have above (p. 19-20) more amply discussed the correctness oi -placing Peachia, Eloaciis and Haloclava in one particular family. On account of the arrangement of the tentacles — the shorter are off-shoots of the endo- coels — we might possibly establish a sub-family Peachiinae for these genera, and bring together the others in a sub-family Halcampoidinae with the endocoel-tentacles of the first order longer or as long as the other tentacles. The colunm is smooth in Halcampoides, A cthelmis, Phytocoetes, Harenactis, Siphonactinopsis, Mesacmaea andPeachia; in Halcampella, Scytophorus and Pentactinia furnished with "i7a/caw/)«-papillae"; in Eloaciiswith. low, rounded papilliform tliickenings, mainly composed by the ectoderm, and in Haloclava with longitudinal lines of ampuUaceous papillae in the distal part of the body-wall. The papilliform thickenings of Eloaciis ^ Probably Halcampella endromitata has no sphincter. To judge from the arrangement of the mesenteries, this species seems to agree with Halcampella maxima and with a new species, H.robuita, not as yet described by me. They have no sphincter, and the very weakl)- developed, imperfect mesenteries only occur in the most distal part of the body. A schematic figure, placed at my disposal by Dr. Andres, namely shows that in H. endromitata only 12 mesenteries are developed below the actinopharynx. In contradistinc- tion to this, the imperfect mesenteries are developed along the whole body in the genus Cactosoma, which within the family Halcam- pidae corresponds to Halcampella within the Halcampoididae. Concerning the Halcampella Oustromovi, described by W3'ragewitch (1905), its systematic position is dubious. Its very little size (the animal was 2 — 3 mm long), its inconsiderably developed reproduc- tive organs and its other structural features, indicate that the species has not yet gained its definitive size. W. declares that it has no sphincter; it is, however, possible that it was overlooked by him, because of the littleness of the animal. Below the actinopha- rynx there are unto 32 mesenteries developed, which seem to indicate that we possibly have to do with a Cactosoma. If we do, however, so far see good to accept the statement of W., concerning the sphincter, it is necessary to propose a new genus for H. Oustromovi. The new genus, Synhalcampella , may be characterized as follows: Halcampoididae with the column divisible into three regions, physa, scapus and capitiilum. Physa without apertures. Scapus probably with "//a/f(irapa-papillae." No sphincter. Tentacles more than 12, rather short, dactyliform. Siphonoglyphes probably in- distinct, without a conchula. 2 pairs of directives. Only the ''Echvardsia-masewieries" perfect, with pennons (only the 2 lateral couples of mesenteries fertile and with filaments). The 5th and the 6th couples and the mesenteries of the younger cycles weak, without pennons along the whole or almost the whole length of the column. ACTINIARIA 8l and the papillae of Haloclava are to be regarded as slight stinging batteries (compare these genera!). A ventral siphonoglyphe only occurs in Peachia, Haloclava, Eloactis, Pentactinia, Harenactis, Si- phonadinopsis, Mesacmaca and Scytophorus; in the last genus it is rather slightly differentiated. The other genera have either no siphonoglyphes or 2 not very distinct ones. A biradiate, hexamerous arrangement of the mesenteries we iind in Halcampoides, Acthelmis, Halcampella and Harenactis, though also here traces of the bilateral development often appear, in as much as the 5th and 6th couples of the mesenteries of the first cycle are weaker than the others of the same cycle. Scytophorus is furnished with 7 pairs of mesenteries with apparently one pair of directive mesenteries, the ventral one. In Mesacmaea which has not been ana- tomically examined in details, 7 pairs of stronger mesenteries seem to be found, according to Andres's notes which have been placed at my disposal. The ventral directive mesenteries belong to the stronger mesen- teries, while the dorsal directives are weaker and in size like the mesenteries of the second order. In another work I will give a more minute account of Andres's notes. Pentactinia has 10 pairs of mesenteries; the ven- trolateral pairs of the second cycle are not developed. Peachia, Eloactis and Haloclava also have 10 pairs, but here the dorsolateral mesenteries of the second cycle are absent. Finally Siphonactinopsis is furnished with 20 pairs of mesenteries. Reproductive organs are developed on all mesenteries in Halcampoides, Scy- tophorus, Siphonactinopsis, Mesacmaea (according to Andres's notes), Eloactis and Haloclava. Cihated streaks are present on all examined species. As to Harenactis Torrey (1902) has not given any minute inform- ations concerning its filaments. In Scytophorusthe ciliated streaks are discontinuous and found in several differ- ent portions along the middle streak. According to Torrey cincUdes^ occur in Harenactis and according to Annandale (1915) in Phytocoetes. I have also found cinclides in Eloactis. Spirocysts seem to be absent in the tentacles and oral disc of Eloactis and Haloclava. To this family also the genus Polyopis, proposed by R. Hert wig (1882), may probably belong. Unfor- tunately a controlling of Hert wig's investigations of the already at the date of his investigation ver\- deformed specimen is no more possible, as there is not much left of the specimen now, and what remains has probably once been exsiccated. Therefore I must restrict myself to some general reflections on Hertwig's descrip- tion. Concerning the reduction of the tentacles his statement may be admitted with the greatest reserva- tion. It is possible that the animal has thrown off its tentacles, another eventuality is that the tentacles have been torn off or contracted so strongly that they project only as low walls. It was namely proved by a control examination of Liponema (Mc. Murrich 1893, Carlgren 1899) — a genus devoid of tentacles, according to Hertwig — that the tentacles had been thrown off. R. Hertwig's statement that Sicyonis has ver\' short papilUform tentacles with large stomidia, is also incorrect. True enough, the tentacles of Sicyonis are short, but they are not so reduced as Hertwig thinks, and the large stomidia are notliing Init artificial products due to the bad preservation of the tentacles, as I will afterwards prove. Finally we might presume that the tentacles of Polyopis had been invaginated in the coelenteric cavity before the mace- ration (comp.p.79). I, for my part, do not think that the tentacles of Polyopis have been reduced, at any rate not in such a way as described by Hertwig. Be this as it may, the rounded proximal body-end and the absence I Stephenson (1920, p. 447) also names the apertures in the physa or proximal end cinclides. Though the walls, surround- ing the cinclides and the apertures in the physa or proximal end, are of about the same structure, I think that it is most practical to retain the name of cinclides in its original extent. The Ingolf-E.vpedition. V. 9. ' ^^ / §2 ACTINIARIA of a sphincter indicate that the genus may be placed to the family Halcampoididae. The openings in the acti- nopharynx also seem peculiar to me and may require a control examination. Hertwig declares that the number of mesenteries is 36; if we narrowly examine his figure 11 B, PI. 11, which represents the aboral body- end seen from the gastral side, we find some ridges corresponding to the basal part of the mesenteries. Judg- ing by the ridges I cannot but find that the animal has 20 pairs of mesenteries, 8 stronger and 3 weaker pairs in 4 compartments. I do not see a single reason for the necessity of establishing a distinct family for this so imperfectly known genus. If we are to keep the family Polyopiidae, there is no doubt that its place is with the group Athenaria. Possibly Polyopis is related to Siphonactinopsis, as both are provided with 20 pairs of perfect mesenteries. Genus Halcampoides Dan. Diagnosis: Halcampoididae with elongated body. Column not distinctly di\asible into regions, with 2 cycles of apertures in the rounded, physa-shaped proximal body-end, smooth, without " Halcampa- papUlae" or spirocysts in the ectoderm, without a cuticle. No sphincter. Tentacles 12, rather long, cylindri- cal, not bulbously swollen in the apex. Siphonoglyphes 2 somewhat indistinct, without a conchula, 2 pairs of directive mesenteries. Only 6 pairs of mesenteries, all perfect and fertile. Cihated streaks of typical ap- pearance. Stephenson (1918 a, p. 10) has placed Halcampoides and Halcampella, viz. Hertwig's species Halcampella maxima in a genus Halcampoides. This arrangement does not seem very suitable to me, as Hal- campoides with its smooth column and its indistinct region-division is essentially differentiated from Hal- campella, which shows a distinct division in regions of the column and is furnished with "Halcampa-papillae." If Halcampoides should be connected with another genus, it would be with A cthelmis to which it is indubitably very nearly allied. Stephenson's species, Halcampoides aspera also ought to be named Halcampella aspera, under the supposition that the type H. endromitata has an endodermal sphincter. If the spincter is meso- gloeal in the type-species, Hertwig's Halcampella to which also Halcampoides aspera belongs, should have a new name, for which, in that case, I would propose Epihalcampa (compare p. 80). Halcampoides purpurea (Stud.) Carlgr. PI. I, figs. 34, 35. PI. 2, ligs. II, 12. Halcampoides purpurea n. sp. Studer 1878, p. 545. PI. 5, figs. 2oa,b. — — Stud. Andres 1883, p. 315. Haddon 1889, p. 336. Kwietniewski 1896, p. 586, PI. 25, figs. I — 4. Appellof 1896, p. 13. Halcampoides abyssorum n. sp. Danielssen 1890, p. 93, PI. 5, fig. i, PI. 15, figs. 4 — 11, PI. 16, figs, i — 3. Mc. Murrich 1913, p. 969. Aegir frigidus n. sp. Danielssen 1887, PI. 2, figs, i, 5, 6, 11. 1890, p. 151, PI. 5, fig. 4, PI. 18, figs. 5 — 10, PI. 19, figs. 1—4. Fenja mirabilis n. sp. Danielssen 1887, PI. i, PI. 2, figs. 2—4, 1890, p. 144, PI. 17, figs, i— 14, PI. 18, figs. 1—4. ACTINIARIA 83 Halcampa clavus Quoy a. Gaimard. R. Hertwig 1882, p. 82, PI. 3, figs, i, 4, 10, PI. 12, fig.s. 8, 9, 11. PI. 13, fig.s. 2, 4, 7. Tizard and Murray 1881, p. 674. Haddon i88g, p. 336. Pax 1910, p. 304, 1914, p. 585—586. Halcainpoidcs clavus (Quoy a. Gaimard? Hertwig) Appellof 1896, p. 13, PI. i, 2. Hakamponiorphe clavus (R. Hertwig) Carlgren 1893, p. 38 (1900, p. 1170). Halcampoides elongaius n. sp. Carlgren in Stephens. 1912, p. 58 (8). Halcampa septenlrionalis n. sp. Pax 1912, p. 312, 1914, p. 586. Halcampa kerguelensis n. sp. R. Hertwig 1888, p. 28, PI. 2, fig. 5. Appellof 1896, p. 14. Diagnosis: Nematocysts in the ectoderm of the column partly larger, ig — 36 x 3 — 4 /i, partly smaller, (10) 12 — 24 x 1,5 /j; in that of the tentacles 22 — 38 x 2 — 3 fi; in that of the actinopharynx partly smaller, 12 — 14 X 1,5 /j, partly larger 27 — 46 X 3—4 (5) /i. Nematocysts with discernible basal part to the spiral thread 20 — 24 X 4 — 6 /j. (concerning the nematocysts of forma mediterranea compare below). Spirocysts in the ectoderm of the tentacles of variable size from 14 X i,5/ito40 X 4 — 5 11, some capsules sometimes larger. Column with 12 longitudinal furrows corresponding to the insertions of the mesenteries. Longitudinal muscle-pennons in the upper part of the reproductive region with very numerous, high, often (especially in large specimens) rather richly ramificated folds. Outer lamellar part of the mesenteries attached close to the outer edge of the pennons. Parietal muscles strong, well limited, with in the outer parts low, ill the inner ones high folds which in large specimens are from somewhat to very richly ramificated. Mar- ginal stomata present. Colour: Purple-coloured, tentacles brownish {purpurea teste Studer). — Column pale rose-red. Oral disc and tentacles intense crimson, the disc a little paler than the tentacles {Aegir teste Danielssen). — Column flesh-coloured with lighter longitudinal stripes, anterior part pellucid, oral disc pellucid with rose- coloured rays shading off into violet. Tentacles light red, at their base with a brownish- violet patch extending stripe-like along the adoral side right up to the point [Fenja teste Danielssen).— Column rose-red, poste- rior extremity with a faint violet play of colour, oral disc rose-red. Tentacles dark red, shimmering faintly crimson {Halcampoides teste Danielssen). — Column yellowish-white with a play of rose-colour, distal part greyish to whitish-yellow. Tentacles brown, more or less shading off into green. — Column yellowish- white with a play of reddish-violet, here and there with darker stripes. Distal part and the tentacles as the preceding specimens (two specimens from Greenland teste Arwidsson). — Proximal part of the column reddish-yellow, distal part bluish-violet. Tentacles flesh-coloured (a preserv'ed specimen from the Ingolf- Expedit.) — Column flesh-coloured shading off a httle into brown (a spec, from Bohuslan). — Column ochreous-coloured, the distal part more pale (a preserved specimen from Ireland, clongatus). Dimensions: in expanded state to 4,5 cm (teste Studer). — Length of the body 7 cm, largest breadth 2,4 cm (a very large preserved spec, from the German Tiefsee-Expedition) . — Length of the body 1,5—2 cm, breadth 0,5—1 cm {clavus in prescribed state teste Hertwig). — Length of the body 1,5—2,5 cm, largest breadth 0,7—1 cm {kerguelensis in preserved state, teste Hertwig). — Length of the body 10 cm., largest breadth 1,5 cm. Length of the tentacles i cm (a preserved spec, from Naples). — Length of the body 7 cm, breadth 1,5 resp. 1,2 cm {Fenja and Halcampoides in expanded state, teste Danielssen). — 84 ACTINIARIA Length 5,5 cm, largest breadth o,g cm (a spec, from the Ingolf-Exp. in preserved state). — Length 3,6 cm, largest breadth 2,5 cm (a spec, from Scoresby Sound). — Length 3 cm, breadth in the distal part 0,7 cm. {elongaius from Ireland). Occurrence: West-Greenland. Davis Strait 65°!!' N 53°35' W 48 fms. green clay (Inge- gerd and Gladan-Exp. 1871), Nordre Stromfiord (Nord- mann St. 2) Godthaab 100 fms. Amniondsen. East-Greenland. Scoresby Sound, Hurry Inlet (Greenland-Exp. 1900 Soren Jensen), Cape Dal ton 9 — 11 fms. (Greenland-Exp. 1900, Soren Jensen), Fame Isl. 5 — 8m, mud, 70°5o' N. 22°33' W. Vs 23 — 28 m (Sw. Greenland-Exp. 1899), Cape Stewart 13 — 18 ni, mud, stones, algae (Sw. Greenland-Exp. 1899), Franz Joseph fiord. Outer part of the Myskoxe fiord 220 m (Sw. Polar- Exp.), Mackenzie bay, N. of Franz Joseph fiord I — 35, m, mud and sand (Sw. Polar-Exp. 1900), Greenland without locaUty. . NE. of Iceland. 65°33' N. io°28' W. 492 fms. Temperature at the bottom -^-0,3° (Ingolf-Exp. St. 107). Faroe Channel. 6o°29' N. 8°i9' W. 374 fms. Temp, at the bottom -h 0,5° (Knight Errant-Exp. 1880 septentrionalis) 6i°o8' N. 9°28' W. 820 m (Thor-Exp. 1904 St. 78). W. of Northern Norway 66 "41 N. 6°59' E. 640 m, coarse-grained clay. Temp, at the bottom H-o,9° (Norw. North Atl.-Exp. 1877, St. 124), 68°2i' N. io°4o' E. 836 m. Sand and clay. Temp, at the bottom ^0,7° (Norw. North Atl.-Exp. 1877, St. 164). (Norw. North Atl. Exp. 1877, St. 173—174), 7i°25' N. i5°4i' E. 1134 m, qlay. Temp, at the bottom ^ i" (Norw. North Atl.-Exp. 1877, St. 200). Behring Sound. 2 miles N. of the winter-haven of Vega. 12 fms., stones and sand (Vega-Exp. 1878) NW. of Behring Sound 66°58' N. 171 °35' W. 21 fms. (Vega-Exp.). Sweden. Bohuslan. Outer part of the GuUmar fiord. Bonden (Carlgren 1895, I sp. elongaius). Further distribution: Ireland. 21 miles E. V4 N. of Clare Island light house 21 fms. (Helga-Exp. I sp. elongaius). The Mediterranean. Naples (Lo Bianco, i sp. probably from deep water). Antarctis. Kerguelen 6 — 100 fms. mud (Gazelle-Exp. purpurea), Betsy Cove 49°i6' S. 70°i2' E. 25 fms. Christmas Harbour 120 fms. (Challenger- Exp. claims) London river no fms., Cumberland bay 105, 127 fms. (Challenger- ACTINIARIA 85 Exp. kerguelensis) 48°57'8 S. 70°o6' E., 88 m (German Tiefsee-Exp. 1898). South Georgien 54°22' S. 36°28' W. Kocktopf bay 22 m, clay and algae (Sw. South Polar-Exp. 1902, N. 33), 54°!!' S. 36°i8' W. Cumberland bay 252— 310 m, gray clay with stones. Temperature at the bottom 1,45° (Sw. South Polar-Exp. 1902 N. 34), Graham region about 64=3' S. $f>'T,7' W. 360 m? Clay. (Sw. South Polar-Exp. 1902, St. 6). Exterior aspect: The body is either cyhndrical or oval, according to the state of contraction. Very expanded specimens reach a considerable length, and also in very contracted specimens tlie length is much larger than the breadth. The column, secerning a mucus-membrane, shows no distinct division in re- gions. The proximal part is rounded, physa-shaped and perforated by apertures which are, at least in larger specimens, 24 in number and arranged in two cycles. No central pore is present, which was also stated by Appellof (1896) of the specimens collected by Danielssen. Studer declares that purpurea is furnished with only one aboral pore, an opinion which is adopted by Kwietniewski. This is, however, not the case, as I have been able to prove on the type-specimen. The aboral "pore" is notliing but a lowering, caused by the contraction of the proximal body-end. When the ectoderm is pencilled away here, it is distinctly seen that no central pore is present in the middle of the proximal end, — the presence of such a pore is besides impossible, because of the coalescence of the mesenteries in the centre. On the other hand, I have, in several compartments, found 2 radially placed pores. It admits of no doubt that purpurea resembles abyssorum and clavus, as regards the arrangement of the pores. The column is furnished with mostly distinct longitudinal furrows corresponding to the insertions of the mesenteries, and lacks each trace of papillae; its ectoderm forms no cuticle. The tentacles of the adult specimens, which are short in proportion to the length of the body, are 12 in number, cylindrical, sometimes pointed, according to the state of contraction, and all of the same size. In a small specimen from Cumberland bay, 0,7 mm long and 0,2 mm broad, without reproductive organs, the number of tentacles was only 8. The tentacles all may be invaginated, so that the ectoderm is turned inwards, thus we may find now one or two, now almost all or all the tentacles invaginated. In the latter case the animal seems to be without tentacles, and on the margin of the oral disc only crateriform openings, surrounded by walls, are to be observed. The tentacles sometimes show shallow longitudinal fur- rows, sometimes a deeper furrow appears on the middle of the tentacles — also obser\'ed by Appellof. In H. claims Hertwig has seen a longitudinal furrow both on the inside and the outside. Any greater im- portance in systematic respect I cannot ascribe to these furrows, as they are most probably due to an irre- gular contraction of the tentacles. The oral disc is broad and radially sulcated. The siphonoglyphes are not distinctly differentiated from the outer part of the actinopharynx and lack gonidial-tubercles and aboral prolongations. The actinopharynx is short, of al)out the length of the tentacles and provided with 12 high longitudinal ridges, extending directly into the middle streak of the filaments. On the actinopharj-nx of the preserved specimens numerous transversal folds are also to be observed. Anatomical description: The ectoderm of the column is liigh with numerous gland-cells. The nematocysts are of two different kinds here, in the actinopharynx of three kinds, one of which has a dis- cernible basal part to the spiral thread; in the tentacles there is only one kind of nematocysts. The size of ACTINIARIA Fig. 107. Textfigs. 102 — loS. Halcampoides abyssorum. Transverse sections of pemions. Figs. 102 — 103 from small, not sexually ripe specimens (fig. 102 spec, from Bohuslan, fig. 103 spec, from Ireland), fig. 104 from a large specimen from Scoresby Sound, fig. 105 from the large specimen from Naples. Fig. 106 from the very large spec, from the German Tiefsee Exp., figs. 107 — 108 from two specimens of H. "kerguelensis". The five last sections have been taken in the upper part of the reproductive region. Fig. 108. ACTINIARIA 87 the spirocysts and the nematocysts of several specimens I have given below in /i, a. typical nematocysts, aa. nematocysts with discernible basal part to the spiral thread, b. spirocysts. Column a a a tentacles b a actinopharynx a aa I) 2) 29 — 31 X 4 u 27—36 X 3—4 17 — 20 >c 14—19 X 1.5 ft 1.5 30—38 X 29—35 X 3," 2.5 —38 X 14x1.5—34 X 4^ 4 39—46 X 4(5) /' 19—22 X 1.5 27—34 X 5/* 3) 29—36 X 3—4 17—24 X 1,5 26—31 X 2—2,5 —36 X 4-5 31—37 X 3—4 17 — 22 X 1,5 29—31 X5— 6 4) 5) 19—26(36) X 3—4 26 — 31 X 3 — 4 13—17 X 14—17 X I— 1.5 1,5 26 — 29 X 2,5 —37 X 4-5 27—30 X 2.5—3 12—14 X 1,5 20 — 24 X 5 6) 24—30 X 3—4 14—17 X 1,5 24—31 X 2—2,5 — 26 X 4 31—37 X 3 17—22 X 1,5 22—26 X 5 7) 24—29 X 3 14—17 X i>5— 2 24—31 X 2.5 19 X 1.5—36 X 4 34—41 X 4.5 19—23 X 1,5 29—31 X 5 «) 22 — 25 X 2,5 — 3 12 19 X 1.5—2 26—34 X 2,5 19 X 1,5—36 X 4.5 31-41 X 4 12 — 17 X 1,5 31 X 5 9) 21 — 26 X 3 (lo) 12 X I— 1.5 22 — 25 X 2 17 X 1-1,5—38 X 5 31—38 X 4 22 X 1,5 29 X 5 10) 28 — 32 — 28—32 -36 36 — — ") — 14 — 16 24 — — 22 — 24 26 — 31 X 6 12) — 19 22 X I — 2 19 — 23 X 1.5—2 19 X 1,5—37 X 4 26—34 X 3—4 22 — 24 X 2 34—38 X 6—7 i) sp. from Scoresby Sound, size see above! 2) sp. from Hurry Inlet, length about 4cm, breadth 3 cm. 3) sp. from NW. of Behring Sound, length 3,8 cm, breadth 1,2 cm. 4) sp. from the Ingolf-Exp. size see above! 5) a small specimen from Hurry Inlet, breadth 0,3 cm. 6) sp. from Scoresby Sound, length 1,8 cm, breadth I cm. 7) sp. from the German Tiefsee-Exp., size see above! 8) sp. from the Graham region, length 4,5 cm, larg- est breadth 1,3 cm, length of the tentacles 1,4 cm. 9) kerguelensis. 10) clavus. 11) clongatus, size see above! 12) sp. from Naples. The dimensions of the nematocysts of the specimen 9 are only approximate, as they refer to old measurements from 1897. If we disregard the specimens 11 and 12, in the column of which I have not found any large nema- tocysts, the other specimens do xexy well agree. The nematocysts of the specimen from Naples, however, are a little different in size, wherefore we might possibly consider it as a distinct variety to which also elon- gatus probably belongs (compare below!). The nematocysts of the column are few in the middle part of the body, in the distal part numerous. The mesogloea is of ordinary' thickness. The endodermal circular muscles are not very much developed and form no separate sphincter. The sphincters which are mentioned by Hert- wig in clavus and the distal sphincter, which Appellof stated to be present, are nothing but local phenomena of contraction. The ectoderm of the tentacles is verj' high, the ectodermal muscles a little ramificated, but low, and the mesogloea of ordinary thickness ; the endoderm is the thinnest layer. The ectoderm of tlie actino- pharynx contains numerous, large, typical nematocysts, while the other nematocysts are few or very rare. It is devoid of ectodermal muscles. The siphonoglyphes are but slightly differentiated, as regards their histo- logic structure. There are 6 pairs of mesenteries, of which 2 pairs of directives; they are all perfect and fertile. In younger specimens the 8 " Edwardsia-va.es,&r).ttnQs" are stronger than the other mesenteries, what has been, observed by Hertwig as well as by Appellof, and what also I confirm. The longitudinal muscle-pennons are very strong, with high, and especially in older specimens, very ramificated folds in the reproductive re- gion. In younger specimens the folds are less numerous in the reproductive regions or in the part where such folds are afterwards developed, but they are thicker than in older specimens. Thus the pennons of the "don- og ACTINIARIA ga^Ms"-specimens, reproduced in the textfigures 102 — 103, which were not sexually ripe, show fewer folds than the pennons of ripe kerguelensis-specimens (textfigs. 107 — 108), and the pennons of these latter spec- imens have considerably thicker folds than those of the larger ones from Greenland (Scoresby Sound), the Mediterranean and Kerguelen (Germ. Tiefsee-Exp.) (textfigs. 104 — 106). The conformity between the pen- nons of these latter specimens, and between these and the pennons of purpurea, is very great, and the pen- nons of these three forms (textfigs. 104 — 106) are on their inside furnished with low folds which were also traceable on the other reproduced sections, excepting the first one which has been taken from the j'oungest specimen. The outer lamellar part of the mesenteries is in all specimens attached close to the outer edge of the pennons. The parietal muscles, which are not expanded on the column, are strong and distinctly out- lined in the reproductive region. In the textfigures 109 — 118 I have reproduced these muscles of several specimens from different localities. However varying their appearance may seem to be, it is common to them all that the folds of the muscles are weaker on the outside than on the inside. In the younger, not sexually ripe specimens the parietal muscles are extended and the folds not ramificated or only inconsiderably so. The extended form is distinctly conspicuous in elongatus (textfigs. 109, 113), but also in young specimens from Scoresby Sound, (textfig. iii, length and breadth of the animal about 0,5 cm — textfig. no, length of the animal about 1,5 cm, breadth 0,45 cm). The parietal muscles of the Ingolf-specimen (textfig. 116) and those of the specimen from Naples (textfig. 115), of which the former are devoid of reproductive organs, the latter has such, are more broad than they are long, while the others are rather expanded. The parietal muscles of the largest specimens are the most richly ramificated, figs. 112, 115, 117, 118. Below the repro- ductive region, where the parietal muscles begin to fuse into the longitudinal muscle-pennons they are more expanded, as seen on the section from the Naples-specimen in textfig. 114. We thus find that the appear- ance of the parietal muscles in the reproductive specimens varies considerably in the reproductive region; in younger specimens the folds are less numerous, more thick and a little ramificated, in older ones more numerous, more thin and richly ramificated. In younger specimens the parietal muscles are besides more radially extended while in older ones they are more concentrated, a memento that we are not uncritically to put up new species, only on basis of a different appearance of the parietal muscles. The ciliated streaks are well developed and the intermediate streaks well differentiated. The median streak forms a direct pro- longation of the longitudinal ridges of the actinopharynx. The cnido-glandular tract is very long. In several specimens I have observed a small oral stoma. Also a marginal stoma is present. The species is dioecious. Remarks: As this species has played a certain part in zoogeographical respect I have above given a more than usually detailed description of its anatomy. I also would advise a stricter analysis of its rather intricate synonymy. The Antarctic forms are the first to be discussed. As regards Actinia clavus Quoy and Gaim. which several authors have placed in the genus Halcampa, it is evidently not identical with Halcampa clavus R. Hertwig, which Pax 1912, after having examined some types of Quoy and Gaimard, was willing to place together with the species of these authors. The difference in their anatomy is namely considerable. The presence of a single deep siphonoglyphe in the species of Quoy and Gaimard is enough to prove that we have to do with quite another genus than that of Hertwig. Andres (1883) has a more correct under- standing of its systematic place as he names the former Philomedusa (= Bicidium) clavus, which name also ACTINIARIA Textfigs. 109 — iiS. Halcampoides abyssorum. Transverse sections of parietal muscles (Figs. 112, 115, 117, 118 in the reproductive tract). Figs. log — III, 113, 116 from not se.Kually ripe specimens (fig. log spec, from Bohuslan, fig. no spec, from Scoresby Sound, fig. m spec, from the same locality, fig. 113 spec, from Ireland). Figs. 112, 114, 115, 117, 118 from adult specimens. The section fig. ri2 is the outer part of the mesentery reproduced in fig. 104. Fig. 114 spec, from Naples. The .section has been taken close below the reproductive tract. Fig. 115 spec, from Naples; fig. 116 spec, from the Ingolf exp. Section in the uppermost part of the cnido-glandular tract; fig. 117. The section is the outer part of the mesentery, reproduced in fig. 107 spec, from Challenger 'Bisp. :^ H. kerguelensis Hertw.; fig. 118 the very large spec, from the Cierman Tiefsee Exp. The Ingolf.Expedition. V. 9. 12 QQ ACTINIARIA Mc. Murrich (1913, p. 969) adopts. That the species of Quoy and Oaimard is a larva of Peachia (= Bici- diuni) is very probable; I will, however, make the reser\'ation that this species possibly may be the larva of a Halolava or of an Eloactis. Unfortunately the figure given by Pax', is of so small dimensions that we cannot form a clear conception of the relation between the longitudinal pennons and the parietal muscles (compare below the conditions in Peachia on one side, Haloclava and Eloactis owihe other), nor of the struc- ture of these latter. Judging by the figure the arrangement of the muscles rather seems to indicate that the species belongs to one of the two latter genera. This might be very easily decided by an examination of the apices of the tentacles and their nematocysts. There is no doubt that the type of Quoy and Gaimard l:)e- longs to some one of the above-named three genera. Hertwig's Halcampa claims, on the other hand, certainly is a species of Halcampoides. Concerning this species Haddon (1889, p. 336) has suggested that it is identical with Studer's Halcampa purpiiyca, to which Kwietniewski (1896, p. 588) objects, while Mc. Murrich (1913, p. 969) thinks that it may pos- sibly be a larva of Halianthella {Edwardsia) kerguelensis (Stud.). The latter view is, to my mind, quite unten- able, as there are pores in the physa of Hertwig's species, but no such in H. kerguelensis. Furthermore re- productive organs are developed in H. claims, and therefore it cannot be a larva. Besides tliis, Hertwig has not observed any mesogloeal sphincter in his species, and he could not possibh' have overlooked the well developed sphincter of H. kerguelensis. On the other hand, Haddon is, as far as I can see, quite correct in his opinion that H. purpurea and clavus of R. Hertwig are one and the same species. It is true that Kwi- etniewski emphasizes that H. purpurea is furnished with a single pore in the physa, while clavus has several such, but, as regards purpurea (compare above!), I do not think that this observation by Kwietniewski is exact, as the physa of both forms is perforated by several pores. The difference in size between the 8 "Ed- wardsia-raesentenQs" and the 4 other mesenteries in H. clavus, in contradistinction to the uniform develop- ment of all mesenteries in purpurea, seems to me to be of little importance as also in the Northern forms I have found the 2 youngest couples, at least of younger individuals, to be weaker than the other mesenteries (Compare also Appellof 1896, p. 13). Halcampa clavus of Hertwig and H. purpurea therefore to my mind are identical species. A third Antartic species, Halcampa kerguelensis Hertw. also seems to me to be identical with H. pur- purea. It is true that Hertwig has pointed out some characters which might serve to distinguish clavus from kerguelensis, but on closer critical inspection I come to the conclusion that these characters are insigni- ficant. The slightly different structure of the pennons is probably connected with the different size of the specimens, furthermore the transverse-sections of the pennons of H. kerguelensis, reproduced by Hertwig, is in no wise typical. Such an arboriform shape of the middle part of the pennon I have never observed, al- though I have sectioned a couple of specimens (compare textfigs. 107, 108). The two sphincters which Hert- wig describes in H. clavus do not deser\'e this name; to my mind, tliey are, as I have above suggested, only indifferentiated circular muscles concentrated through the contraction of the column in these parts. Also the different appearance of the actinopharynx in both species is certainly connected with a different state ' Pax (1914, p. 5S5) seems to adopt the opinion that the species of Quoy and Gaimard is a Peachia. He declares that he has proved this .species to be a Peachia, which to my mind does not appear from his account. ACTINIARIA qi of contraction, and the longitudinal furrows of the tentacles of clavus have no doubt arisen by an accidental, irregular contraction (compare above!). The longitudinal pennons of H. kcrgnclcnsis are not so richly rami- ficated as in Halcampa purpurea, and the folds are thicker than in the latter species which I have above proved to be identical with H. clavus, but this diversity is, in my opinion, due to the different age of the specimens (the specimens of kcrgiielensis were considerably smaller than those of purpurea). I therefore think that Her twig's H. clavus and kerguelensis and Studer's H. purpurea, all dredged at Kerguelen, are the same species. If we now turn to the Northern and Arctic Halcampoides-species, Appellof (1896) has shown that Fenja mirabilis and Aegir jrigidus are identical with H. abyssorum, a view wliich is correct, as far as I can see from Appellof 's description. In addition to Danielssen's species we have to recollect H. septcntrio- nalis, a name proposed by Pax for Halcampa clavus, described by Tizard and Murray, from the channel of the Faroe Islands and, according to Haddon (1889, p. 336), identified by R. Hertwig as his H. clavus. As this form has been dredged in the cold area, it is very probable that it is identical with abyssorum (I have never seen this form myself); there is no reason to give a new name to this form, and Mc. Murrich (1913, p. 969) is of the same opinion. Finally we have to mention Halcampoides elongatus, a species which I ha\'e characterized in a few words (inStephensigia.p. 8) as having weaker and more elongated parietal muscles than H. abyssorum. As I have, however, afterwards found (compare above, textfigs. no — in) that the parietal muscles in young, not adult specimens of abyssorum are provided with sparser folds and are more elongated in the part belonging to the reproductive region than in older specimens, I think that the sup- posed differences in the structure of the parietal muscles of elongatus and of abyssorum are connected with a disparity of age — the specimens of elongatus were young, not adult specimens, and I am probably not mis- taken, if I place H. abyssorum, septentrionalis and elongatus together in a single species, H. abyssorum. The question now remains, whether Halcampoides purpurea and H. abyssorum are identical or not. Almost all authors occupying themselves with tliis question, as Haddon, Mc. Murrich and Pax, have re- garded the Antarctic and Arctic species of Halcampoides as distinct species — in fact no author has examined more than a few of the above-named species, but entirely founded his statements on descriptions from Uterature. Appellof (1896) is the only author who has proposed Hertwig's H. clavus and Danielssen's Halcampoides abyssorum to be the same species; still R. Hertwig has identified H. clavus with the species signified as H. septentrionalis. With an interrogation-mark Appellof has also put up H. clavus Quoy and Gaim. as syno- nymous with the former as well as with Halcampa purpurea. On the other hand, he keeps Halcampoides kerguelensis as a distinct species. After the account given abo\-e — I have had an opportunity to examine all species excepting H. septentrionalis — I do not doubt that they are all identical or, on all accounts, so nearly related that no specific character can be pointed out for them. The species therefore ought to be called Halcampoides purpurea (Stud.) Carlgr. Thus we find here a species occurring now in deeper, now in more shallow water, common to the Arctic as well as the Antarctic regions, but, according to earlier accounts, absent in the intermediate waters. The latter account is, however, probably not correct ; I am inchned to tliink that the species is to be regarded as a cosmopolitan, though it has its largest distribution in the cold area. The occurrence of the species in the ACTINIARIA 92 Mediterranean namely indicates its cosmopolitism. It is true that the nematocysts differ a little in size and occurrence from those of the Arctic and Antarctic specimens, but this difference is not so considerable as to make us want to put up a new species ; it is possibly a separate race or variety {mediterranca) to which the not sexually ripe specimens, taken at the coasts of Bohuslan and Ireland, probably belong. Genus Acthelmis Liilken. Diagnosis: Halcampoididae without spliincter. Column expanded, smooth, without papillae, not divisible into regions or indistinctly so. Tentacles more than 12, not swollen in the apices. Siphonoglyphes absent or very feebly developed. 6 pairs of perfect, fertile mesenteries with longitudinal pennons. Sterile, imperfect mesenteries without pennons, in one or several cycles. Liitken has for Actinia intestinalis Fabr. proposed the genus Acthelmis, but never given any diag- nosis of the latter. In the Arctic regions there are two species, the only hitherto known. Probably the genus Charisea, described by Torrey (1902), is synonymous with Acthelmis, though this author places this genus to the family Actiniidae. The body-shape of Charisea namely indicates that the genus has no distinct pedal disc, and the figures given by Torrey of the muscles of the mesenteries and his description of the rest of the genus agree well with the above diagnosis of Acthelmis. It may besides be that the species C. saxicola is identical with anyone of the here described species of Acthelmis. Acthelmis intestinalis (Fabr.) Liitken. PI. I. Figs. 6—7. Actinia intestinalis n. sp. Fabricius 1780, p. 350, figs. 11 A — C. Andres 1883, p. 588. PFleming 1828, p. 498, PSars 1835, p. 3. ? Johnston 1847, p. 219, textfig. 49. PLandsborough 1852, p. 247. P Norman 1868, p. 318. A. [Acthelmis) intestinalis Fabr. I,iitken 1875, p. 186. Actinocereus intestinalis. Blainville 1830, p. 294, 1834, P- 328- Diagnosis: Column in the proximal end rounded or .sometimes flattened. Division into regions indistinct. Nematocysts of the column and tentacles 14 — 17 X 2 — 3 ii. Spirocysts of the tentacles unto 22 X 3/7. Tentacles 18 — 26 with feebly developed longitudinal muscles. Nematocysts with distinct basal part to the spiral thread 17 — 22 X 4 — 5 [i in the ectoderm of the actinopharynx. 2 indistinct siphonoglyphes. Pairs of mesenteries 6 + 6 + 12, the latter cycle more or less perfect. Folds of the longitudinal pennons liigh, but not very numerous (on transverse-sections through the upper part of the reproductive region about 20, through the lower part about half the number) and ramificated mainly in the outer part. The lamellar outer part of the mesenteries issuing from the outmost end of the pennon. Parietal muscles weak, but ex- panded, with few, scattered, short and thin folds. Mesogloea in the parietal muscle-region thin. Expansion of the parietal muscles on the body-wall inconsiderable. Longitudinal muscles of the imperfect mesenteries of about the same structure as the parietal muscles of the perfect mesenteries, but a little stronger. Well developed ciliated streaks. ACTINIARIA q. Colour: transparent yellowish-white, the proximal part with paler longitudinal Unes (Fabricius). Dimensions: Length in preserved state unto 2,8 cm, breadth 0,25 cm. Length of the tentacles about 0,25 cm. , Occurrence: West-Greenland. Godhavn (Olrik), Ritenbenk (Andersen), Egedesminde (Trau- stedt, Olrik). Greenland without distinct locality (Hoi bo 11). On stones or shells at the shore, also on sand (Fabricius). Further distribution: Shetland Islands (Fleming) (PPerhaps not this species). Exterior aspect: In extended state the body is expanded and cyHndrical; in very contracted state often broader in the proximal and distal ends. (PI. i, figs. 6, 7). Distinct pedal disc absent. It is true that the proximal end of some of the examined species is flattened disc-like, but a distinct outline between the most proximal part and the other part of the body is never to be observed. The proximal part is mostly a little involved in the preserved specimens, but never swollen as a physa generally is. The column is smooth, without papillae, di\'isible into two from each other ver>' little differentiated parts, a longer scapus and a shorter capitulum ; sometimes these regions seem to be separated from each other by a fold, recalling a fossa, which is probably due to the contraction of the body. The scapus seems to be able to generate a thin mem- brane which, however, may be a mucus-secretion. According to Fabricius the tentacles are 18 in number; in 6 species, examined by myself, the number varied from 24 to 26. The tentacles, arranged in three cycles, may be perfectly covered by the column; they are short, conical, not thickened in the apices and almost all of about equal length, the outer tentacles are only a httle shorter than the inner ones. The oral disc is inconsiderable, with shallow, radial furrows. The actinopharynx is short, in the preserved specimens folded and supplied with two weak siphonoglyphes devoid of aboral prolongations. Anatomical description: The ectoderm of the "scapus" is very high and provided with nume- rous nmcus-cells and very sparse nematocysts (14 — 17 X 2 — 3 ji in size). The ectoderm of the capitulum differs from that of the scapus only in this respect that the mucus-cells are verj' sparse here. The mesogloea of the column is tliin and fibriUated. The endodermal circular muscles are a httle stronger in the above- named fold, but not forming any distinct sphincter there. The longitudinal muscles of the tentacles are weak, the spirocysts of the tentacles are very numerous and of variable length, to about 22 x 3 // in size. The typi- cal nematocysts are sparse and of the same length as in the column. The ectoderm of the actinopharynx contains very numerous mucus-cells and numerous nematocysts with distinct basal part to the spiral thread. They are widened in the basal end and 17 — 22 X 4 — 5 n in size. The wall of the nematocysts in the ten- tacles and in the actinopharynx is comparatively thin. In the siphonoglyphes the mucus-cells are very sparse and the nematocj'sts absent or ver>' sparse. The mesenteries are hexamerously arranged, in three cycles. Of these cycles the latter is more or less perfect and only present in the distal part of the body. Thus the mesenteries of the third cycle of a specimen were developed in the dorso-lateral and the lateral exocoels, but not in the ventro-lateral exocoels. Besides this, the mesenteries of the third cycle end at a different level, even the mesenteries of one pair. Only the first 6 pairs are perfect and provided with pennons. Judging by the unequal size of the filaments the ventral 94 ACTINIARIA mesenteries of the ventrolateral pairs are the younger, the dorsal mesenteries of the same pairs the older. The muscle-pennons are provided with high, mainly in the outer parts ramificated folds. In the upper part of the reproductive region, at some distance from the actinopharynx, there are, in transverse-section, about 20 folds (textfig. 119); in the lower part of the reproductive region they are less numerous (textfig. 120). The outer lamellar part of the mesogloea of the mesenteries issues from the exterior border of the pennon. The parietal muscles are but slightly developed. On the pennon-side the short and sparse folds of the parie- tal muscles merge into the longitudinal muscles of the pennon, now there are some rather close folds not far Fig. 119 Fitr. 120 Fit;. 121 Textfigs. 119 — 121. Acthelmis intcstinalis. Fig. iig: Transverse section through a perfect niesenter)- in the uppermost part of the reproductive tract. Fig. 120: A similar section farther clown through mesenteries of the first and second order. Fig. 121: A similar section of a mesentery of the second order. from the pennons, now some higher folds are developed in the middle part of the lamellar region of the me- senteries between the column and the pennon (fig. 119). On the side of the mesenteries opposite to the pen- non the parietal muscles form some sparse folds (textfig. 120), further upwards the folds are stUl sparser, until at last they disappear, and a straight muscle-lamella remains. In the region of the ciliated streaks the parietal muscles are of the same appearance (textfig. 119). The mesenteries of the second cycle are weak, and their muscles with the sparse folds recall on transverse-sections the parietal muscles of the mesenteries of the first cycle in the lower part of the reproductive region (textfig. 121). The mesenteries of the third cycle are still more weakly developed. On transverse-sections I have observ^ed one stoma in the vicinity of the actinopharj-nx. The mesenterial filaments are provided with well de-\'eloped ciliated and intermediate streaks. Only the first 6 perfect mesenteries have reproductive organs. Remarks: The Greenlanders call this species "Kettuperangsak" (Fabricius). ACTINIARIA Qc Acthelmis schaudinnii n. sp. Diagnosis: Column thicker and more robust than in A.intestinalis, and, according to the different state of contraction, cyHndrical or oval. Column not divisible into distinct regions. Typical nematocysts of the column 14 X 2 /i, those of the tentacles 22 — 26 x 2 — 4 fi, those of the actinopharynx 20 — 23 X 1,5 — 2 /i. Nematocysts with indistinct basal part to the spiral thread, widened in their basal end, in the ten- tacles 24 — 26 X 1,5 — 2 /<, in the actinopharynx 24 — 29 (36) X 5 — (6) /.<. Number of tentacles about 34. Lon- gitudinal muscles of the tentacles weak. Siphonoplyphes? Pairs of mesenteries 6 + 6 + an imperfect third cycle ; the folds of the pennons high and rather much ramificated, more numerous than the former species, in the reproductive region about 20 — 30. Insertions of the lamellar part of the mesenteries as in A . intesti- nalis. Parietal muscles weak with large, not numerous, low folds. Mesogloea in the region of the parietal muscles thick. Expansion of the parietal muscles as in the former species. Muscles of the mesenteries of the second cycle, although stronger, recalling the parietal muscles of the first cycle. Colour? Dimensions: Species from Great fiord: length 1,3 cm, largest breadth 0,6cm, length of the ten- tacles about 0,3 cm. — A specimen from New-Zembla: length 0,8 cm, breadth 0,5 cm. Occurrence: Spitzbergen. Great fiord Cape Blanck 77°49' N. 20°3' E. 65 m (Romer «& Schau- dinn 1898) i sp. New-Zembla Besimennaja Ba^^ clay, 4 — 5 fms. (Nordenskiold-Exp. 1875) 4 sp. Exterior aspect: All the specimens were more or less contracted, the proximal as well as the distal ends were drawn in. According to the state of contraction the individuals were cylindrical or more fusiform, the diameter in proportion to the length is, however, in tliis species considerably larger than in A. intcsti- nalis. The column does not seem to be divisible into regions, and its surface is smooth. The insertions of the mesenteries were rather distinct and corresponding to weak longitudinal furrows on the column, which are conspicuous on the involved distal part. The number of tentacles in the specimen from Great fiord was 34. The tentacles were hexamerously arranged and short, as in the former species. The oral disc is inconsider- able. The actinopharynx is of about twice the length of the tentacles, and longitudinally and transversely sulcated. I cannot with certainty decide whether siphonogl5^hes are present or not, they are, at all events, weakly developed, if present, and form no aboral prolongations. Anatomical description: The ectoderm of the column is provided with scattered nematocysts, partly typical, always of equal breadth and about 14 X 2 /.( in size, partly widened in the basal end and larger, 24 — 26 X 5 /^ ; the ectoderm also contains very numerous mucus-cells. The ectoderm is thicker than the mesogloea, especially in the specimens from New-Zembla. The endodermal circular muscles of the column are weak and form no sphincter. The longitudinal muscles of the tentacles are weak and endodermal, the nematocysts of the ectoderm are 22—26 X 1,5—4 ," i" size, — the breadth variates considerably, so that it is probable that there are two different sizes of capsules. The spirocysts are unto 30 (36) fi long. The radial muscles of the oral disc are weak. The ectoderm of the actinopharynx is high, with numerous nematocysts. The straight, riblike nematocysts, reaching a size of 22 — 24 X almost 2 /i, are the most numerous, those which are a little widened in the basal end and show a small, discernible basal part to the spiral thread, are 96 ACTINIARIA somewhat sparser, their size is commonly 24—29 X 5 //, rarely unto 36 X 6 y«. Besides these, I have here found sparse, sometimes a little curved, nematocysts of about 29 X 3 ;< in size. The mesenteries are hexamerously arranged in three cycles, 6 + 6+12, the latter cycle is imper- fect. There are two pairs of directive mesenteries. The first six pairs are perfect and provided with well developed filaments with cQiated streaks. The six pairs of the second cycle are imperfect and of full body- length like the mesenteries of the first cycle, at least several of the mesenteries of the second cycle bear distinct, although not long, filaments. The mesenteries of the third cycle are very weak and only rising a little over the endoderm of the column. Only the first six pairs have pennons; the sixth pair — the ventral mesenteries of the ventro-lateral pairs — is the weakest. The longitudinal pennons are much stronger than in A. inte- Fig. 122 Fig. 123 Textfigs. 122 — 124. Acthelmis schauditmii. Fig. 122: Transverse section of pennon in the lower part of the actinopharynx. Fig. 123; \ similar sec- tion in the reproductive tract. Fig. 124: Transverse section of a mesentery of the second cj-cle. stinalis. The folds are liigh and rather richly ramificated. A transverse-section of a pennon in the lower region of the actinopharynx of the specimen from Great fiord is reproduced in the textfig. 122. (The side of the actinopharynx is turned upwards). In the tract of the reproductive organs the folds are very high and partly much ramificated (textfig. 123, transverse-sections of the specimen from Great fiord). The parietal muscles are weak, the folds are thick, few and low, and recall those of the muscles of the mesenteries of the second cycle, though the folds are stronger here. The niesogloea is strongly developed in the parietal muscle-tract as well as in the mesenteries of the second order, wherefore these part in transverse-sections are of a more robust appearance than the corresponding tracts of A. intestinalis. (The textfigure 124 shows a transverse- section through a mesentery of the second order of a specimen from New-Zembla). The parietal muscles seem to be sparsely spread over the column. Stomata are probably present in the distal part of the mesen- teries. Only the first six pairs of mesenteries bear reproductive organs. The specimen is dioecious. Remarks: The state of preservation of the specimens was not good, wherefore the description is ACTINIARIA 97 not as perfect as desirable. It, however, seems to me that the species is distinctly separated from the former species. In its organisation it moreover recalls Haliactis arctica (p. 129), but as I have not obser\'ed any acontia here, it is no more to be referred to this latter genus. Genus Peach ia Gosse. Diagnosis: Halcampoididae with a well-developed, rounded, aboral body-end, physa, perforated by very numerous apertures (in twelve longitudinal rows H add on). Column more or less cylindrical, often of considerable length, smooth, without "H«/c«>M/>fl-papillae", indistinctly divided in regions, without spiro- cysts and sphincter. Tentacles 12, not hemispherically swollen in the apices, the inner (endocoel-tentacles) shorter than the outer (exocoel- tentacles) . A single, very deep and well differentiated siphonoglyphe with well-developed aboral prolongation. Oral end of the siphonoglyphe drawn out in a more or less lobated socalled conchula. Pairs of mesenteries 10 (6+4 lateral and ventro-lateral pairs). Only the mesenteries of the first cycle perfect, fertile with filaments and with strong pennons passing into the parietal muscles with- out distinct outline. Mesenteries of the second cycle with well-developed, almost pennon-like, muscle-bundles in the endocoels. Tins genus is evidently most nearly related to Eloaciis and Haloclava. Synonymous with Peachia is the genus Siphonactinia of Danielssen and Koren, as before pointed out by several authors. In con- formity with Haddon (1887, p. 475) I also think that Peachia and Bicidium are synonymous. This latter genus, hving parasitically on medusae, is only distinguished from Peachia by the mesenteries of the second order not being developed. These mesenteries seem to originate very late in Peachia. I have namely found a specimen of Peachia in the clay, the mesenteries of the second order of wliich were not developed (compare below under Peachia hastata). This case seems to be prevailing in Eloactis. A specimen of E. mazelii from a depth of 40—50 fms., taken in the Hjiilte fiord Norway, shows very weak mesenteries of the second cycle in only a single exocoel (compare E. mazelii textfig. 142). Furthermore it ought to be remembered that reproductive organs are never found in the genus Bicidium, which is probably nothing but a larva- stadium of Peachia. The conchula, not always observed in Bicidium, also seems to appear very late, and probably alters its form wliile developing. Under such circumstances it is only with a certain resen-ation that the form of the conchula may be used as a species-character in Peachia. Mc. Murrich (1893, p. 145) states that Peachia koreni has only 8 tentacles. It is, however, probable that the animal was a lar\'al form with undeveloped reproductive organs, as also supposed by Mc. Murrich. Peachia parasitica (L. Agas.) Verr. Bicidium parasiticum n. sp. Agassiz 1861, p. 24, 1865, p. 15- Verrill 1864, p. 31. PI- i- figs. 14, 15- Mc. Murrich 1913, p. 969. Hargitt 1914, p. 239, fig. 2. Philomedusa parasitica (Agass.) Andres 1883, p. 324. Peachia parasitica Verrill 1866, p. 338, 343. 1874, p. 739- Carlgren 1906, p. 83, figs. 7 a, b (a more com- plete list of the literature is given in the latter work). 13 The Ingolf-Expedition. V. 9. 98 ACTINIARIA Diagnosis: Nematocj'sts in the ectoderm of the column 25—29 (34) X 3,5 fi, in the tentacles 29 39 X 4 — 5 [I, in the actinopharynx 29 — 41 X 4 — 5 fi, Spirocysts of the tentacles about 17 — 26 x 2,5 /i. Longitudinal muscles of the tentacles well developed. Conchula with three lobes, in extended state large, in contracted more or less distinct. Muscle-pennons in the mesenteries of the first cycle strong, expanded over almost the whole breadth of the mesenteries. The folds of the pennons rather high, in transverse-sec- tions pectinate. Parietal muscles weak, not expanded on the column. Oral stomata and small marginal sto- mata present. Colour: light puri)lish brown with bluish iridescence, similar to that of Cyanca arctica (Verrill). The largest specimen was brownish, in alcohol. Dimensions: The largest specimens dissected by myself were 3,5 cm long and 2,5 — 3 cm broad; the length of the tentacles about 0,9 cm. Occurrence: West-Greenland Egedesminde (Levinsen 1877) i sp., Nordre Stromfiord, St. 9 a (Nordmann) i sp., Greenland without distinct locality (Fasting). Further distribution: North America from Cape Cod to Fundy bay. Nahaut Mass. to Eastport Maine (Verrill), Arctic ocean to Cape Cod (Parker) as larva on Cyanea arctica, as adult at Eastport Maine (Verrill). Exterior aspect: The specimens were rather well preserved. The form of the body was more or less egg-shaped, according to a strong contraction of the distal and basal ends. The column is smooth with somewhat distinct longitudinal furrows corresponding to the insertions of the mesenteries; besides these, there are also transversal furrows produced by the contraction of the column. A distinct fossa is present. The tentacles are short, cylindrical, with a porus in the apex, and more or less longitudinally sulcated, ac- cording to the state of contraction. The number of the tentacles is 12. In the largest specimen one tentacle was invaginated. The oral disc is not particularly wide. The lobes of the con- chula were indistinct in two specimens. In the largest specimen a little protube- / ranee of the conchula is seen near the middle-line on one side; on the other side 4 a similar elevation is probably present, though I cannot confirm it with certainty as the conchula was a Uttle damaged here. In the second specimen the conchula was strongly contracted so that no distinct lobes are visible, in the third specimen it was of the same appearance as on the figure given by Verrill (1864) (Fig. 125 a). The actinopharynx is long, in proportion to the length of the body, and pro- vided with a very well developed siphonoglyphe, the aboral prolongation of which almost equals the length of the actinopharynx. The actinopharynx is longitudinal and transversally sulcated, the transversal furrows are certainly a result of the contraction. Textfig. 125. Anatomical description: The ectoderm of the body-wall is high and Peachia parasitica. , . . . , . „. r .-i m. j n Fig, 125a seen from the oral thicker than the mesogloea. The stratum of nerve-fibnllae and nerve-cells are disc. /; conchula, s: siphono- distinct in the distal part of the ectoderm of the column; in the other parts it is glyphe. I"ig. 1256 seen from the side, after Verrill 1864. not SO much developed. I have measured the nematocysts (h) and the spirocysts ACTINIARIA 99 {sp.) in the different regions of two specimens {a. specimen from Nordre Stromfiord, b. specimen taken by Fasting). They differ considerably in size from those of Peachia hastata and bockii. The size of the cap- sules was as follows: Column n. tentacles n. in spec, a 25—29 (34) x 3.5—4 ft 32—36 X 4—5 ^ in spec, b 25—29 x 3,5 29—39 x 4 (5) tentacles sp. 19 — 26 X 2,5 fl 17 — 22 x 2.5 actinopharyns «. 35—41 X 4—5^ 29 — 41 (commonly 36) x 5 In the specimen a. the nematocysts were typical with invisible basal part to the spiral thread ; in the specimen b. the basal part was discernible. Probably tliis difference is due to the preservation of the cap- sules. The nematocysts are numerous in all regions; the spirocysts of the tentacles comparatively few. The endodermal circular muscles of the column are rather strong, but form no spliincter. The ectoder- mal longitudinal muscles of the tentacles are well developed. The ectoderm of the siphonoglyphe is de- void of nematocysts, and its albumen-cells are few in comparison with those of the actinopharjmx, which has no longitudinal muscles. The number of the mesenteries is that typical of Peachia. In one specimen one dorso-lateral pair of mesenteries is weak and a little coalesced with the actinopharynx. It is expanded in aboral direction a short distance below the actinopharynx (compare below the description of a young specimen of Peachia hastatal) The muscles of the mesenteries mainly are of the same appearance as in other Peachia species. The longitudinal muscles, however, form no concentrated pennons in the region of the glandular streak, but are spread over almost the whole breadth of the mesenteries (textfig. 127), wlierefore the pennons look more like a ribbon. The folds are rather high and mainly of about equal height, here and there with certain inter- spaces; there are, however, also lower folds. In transverse-sections the pennon recalls a comb. The pennon merges into the parietal muscles without distinct limit. Below the region of the filaments the pennons are more contracted (textfig. 126). The parietal muscles are weak with few and low folds, on the pennon-side not distinctly differentiated from the pennon, on the opposite side distinctly Umited, but not reaching the distal end. They are not expanded on the column. The mesenterial filaments are of typical appearance and only developed in the mesenteries of the first cycle. Stomata are present on the perfect mesenteries. The oral stomata are large, but the marginal stomata very small and placed in the vicinity of the oral disc. I have not observed any reproductive organs in the specimens I have sectioned. 13* jPQ ACTINIARIA Peachia hastata Gosse. PI. I, figs. 21 29. PI. 2, fig. 13. Peachia hastata n. sp., Gosse 1855, p. 267, PI. 28. — — Gosse, Haddon and Dixon 1885, p. 399 — 405, PI. 16 (in this work synonymy and litera- ture to 1885). Haddon 1889, p. 338 — 340, i textfig. Faurot 1895, p. 94 — no, figs. 7, 8, 10—15, PI. I, figs. 1—3, PI. 2. figs. 3, 5, PI. 3, figs. 3—6, PI. 5, fig. 6, PI. 6, fig. 5, PI. 7, PI. 9, PI. 12, textfig. 12. Carlgren 1904, p. 538, textfigs. 2, 4, 1906, p. 81, fig. 6, a — li (Lite- rature of the larvae). Nafilyan igi2, p. 9. Mc. Murricli 1913, p. 967. Diagnosis: Nematocysts in the ectoderm of the column 12 — 16 x 2 u, in the tentacles 17 — 22 x 2 — 2,5//, in the actinopharynx 19 — 24 x 2 11. Spirocysts in the ectoderm of the tentacles 12 — 19//. Lrongi- tudinal muscles of the tentacles well developed. Conchula large with 6 to 10 lobes. Pennons of the mesen- teries of the first cycle strong, spread over the greater part of the breadth of the mesenteries. Folds high, in the outer part arranged more or less like palisades, in the inner part often ramificated. Parietal muscles weak with only a few folds. Pennons of the mesenteries of the second cycle comparatively strong with high folds. Oral stomata present. Marginal stomata? Colour: The most distal part of the column, "capitulum" and the "physa" in adult specimens trans- lucent, flesh-coloured or almost salmon-coloured, usually richly splashed with reddish-brown in irregular, longitudinal lines. Tentacles translucent, pinkish or v^ery pale purplish-brown, on the inside with 4 — 5 more or less distinct W marks and bands. The back of each tentacle has an opaque white spot about halfway be- tween the base and the tip. Oral disc pinkish-white, inter-radial lines with brown and white spots and marks. Conchula flesh-coloured or pale pink, lobes with a brown or deep-red core, usually with a white apical spot. Actinopharynx with twelve dark-brown bands, alternating with broader orange-buff bands, further down the colour is reddish or purj^le (Haddon & Dixon 1885, p. 401 — 402; in this work a more complete descrip- tion of the colour). Dimensions: Length of the body 2,5 to 10 cm in contracted state, in expanded state unto 20,5 cm. Breadth i — 2 cm (Haddon & Dixon). The length of the tentacles about equal to the diameter of the column. Occurrence: Denmark. Frederikshavn (Schmidt 1S72) 2 large specimens. Sweden. GuUmar fiord (The el and Carlgren 1905. Larvae on hydroid-medusae, and a small specimen on the clay in "Bondhalet"), Vinga 50 — o m. GuU- mar fiord 75 m. Koster fiord 230 — 0 m (Bjorck 1910, Larvae on hydroid- medusae). , Further distribution: North-Sea. Heligoland to British Isles. NW. France. Roscoff, Douar- nenez bay, Lannion, Banyuls-sur-Mer. Exterior aspect: The body is elongated and the column without distinct division in regions. In the expanded state of the animal, physa, capitulum and scapus — according to Haddon and Dixon — are to be distinguished. Any distinct limit, especially between the capitulum and the scapus, hardly existing, it seems to me rather arbitrary to make this distinction. The "physa" is ampullaceous in expanded state ACTINIARIA jQj and perforated by numerous apertures, arranged in 12 longitudinal rows (Haddon 1889, p. 337); it may be perfectly involved. The column is rugose in contracted state, in expanded smooth. According to Haddon and Dixon 1885, p. 401) it is furnished "with numerous minute suckers." I have carefully examined spec- imens received from Haddon; they were in certain parts of the body strongly expanded, partly in trans- verse-sections, partly in preparations in toto in glycerine. As far as I can make out there are no "suckers", nor such low elevations as on the column of Eloactis. It seems to me that the "suckers", which nowise deserve this name, are nothing but cell-accumulations containing some more supporting cells than the other parts of the ectoderm. By an examination of the surface of the column, in preparations in toto, it is namely clearly seen that the main part of the mucus-cells form an irregular net-work, between which are distributed some more compact parts of the ectoderm, mainly consisting of supporting cells, but also of scattered mucus-cells. The tentacles are 12, arranged in two cycles, the inner tentacles are shorter than the outer ones and issue from the endocoels, while the latter are exocoel-tentacles, an arrangement distinctly appearing in the larvae, but also visible in the adult animal. Thus I cannot agree with Haddon and Dixon that the tentacles are monocychc. On the other hand, the description of the arrangement of the tentacles given by Faurot (1895) is exact. (Compare also Carlgren 1904). As to their form they are cyUndrical, a httle atte- nuated towards the apex and of about the same length as the diameter of the body. The oral disc is smooth, flattened and provided with radial furrows corresponding to the insertions of the mesenteries. The mouth is wide, in live animals commonly covered by the conchula. The conchula is strongly developed, consisting of three main lobes, one in the directive plane and two lateral ones. From these smaller lobes tentacle-hke prominences issue, so that the total number of lobes varies from 6 to 10 (Haddon and Dixon), according to the age of the animal. In the larvae and young spec- imens only the main lobes are developed (compare below!). The other part of the siphonoglyphe is very deep, distinctly differentiated from the other part of the actinopharynx, smooth, not wrinkled, and pro- vided with a very long aboral prolongation which is twice as long as the main part of the actinopharynx. This latter is comparatively short, of about the same length as the diameter of the body, longitudinally sulcated, and in contracted state also with transversal folds. On the side of the aboral prolongation of the siphonoglyphe the actinopharynx is continued as narrow lamellae (compare below!). Anatomical description: The anatomy of the adult species is described by Haddon (1889) and Faurot (1890, 1895). The latter (1895, p. 94) gives a more detailed description of the species, with nume- rous figures of sections through different parts of the body. Besides this, Sedgwick 1884, p. 43) has pub- hshed some anatomical details of the species. In some respects the anatomy is, however, imperfectly de- scribed. For anatomical examination I have used partly a specimen from Frederikshavn, partly and mainly specimens from Ireland, dredged by Haddon, partly the sections made by Haddon who has placed them at my disposal. The ectoderm of the column is ordinarily developed, in the contracted state of the animal thick and furnished with numerous mucus-cells, arranged as I have shown above. Its nematocysts are not numerous, and 12 — 16 X about 2 n in size. The mesogloea is longitudinally and transversally stratiform as in Hakampa, and of ordinary thickness. The endodermal circular muscles are rather well developed, but form no spliincter. ACTINIARIA 102 The ectoderm of the tentacles is high and contains numerous, small nematocysts 17 — 22 x 2 (2,5) n in size, and very numerous spirocysts, 12 — 19 // long. The ectodermal muscles of the tentacles are weak. The ectoderm of the actinopharynx is thick, folded and provided with nematocysts 19 — 24 x 2 /i in size, often a little curved, widened in the basal end, and with indistinct basal part to the spiral thread. Besides these, there are, in addition to supporting cells, also mucus-cells here, considerably broader than those of the siphonoglyphe. The ectoderm of the siphonoglyphe is thicker than in the other part of the acti- nopharynx, and composed of supporting cells with long cilia. At the basis of the ectoderm there are rather numerous, long, granulous glandular cells, which are in communication with the surface of the ectoderm through a narrow duct. At the transition between the siphonoglyphe and the actinopharynx the ectoderm is a little differentiated. The supporting cells carry stronger cilia here than in the other parts of the actino- pharynx and the siphonoglyphe, and the nuclei commonly are more elongated, while they are round in the other parts of the actinopharynx and the siphonoglyphe (PI. 2, fig. 13). Some cells of this zone might, how- ever, be ordinary supporting cells, as round nuclei are also visible here and there. These strongly ciliated ribbons are comparatively broad at the oral side, but gradually become narrower and seem to end at some distance from the lower edge of the aboral prolongation. Probably these strongly ciUated parts are of some particular physiological importance, as they form a boundary between the siphonoglyphe and the other part of the actinopharynx. The mesogloea of the siphonoglyphe is considerably thinner than the ectoderm, but thicker than that of the actinopharynx proper. The endoderm of the siphonoglyphe is strongly vacuo- lated and very high in the exocoel-parts, in the actinopharynx proper lower and not so rich in vacuoles. A distinct stratum of nerve-fibrillae with few nerve-cells and a weak longitudinal muscle-layer is present in the ectoderm of the siphonoglyphe and the actinopharynx. The conchula with its hollow prominences is built as the siphonoglyphe. The aboral prolongation of the siphonoglyphe also contains parts of the acti- nopharynx itself. On both sides of the middle part of the prolongation, consisting of the siphonoglyphe, the actinopharynx is namely continued, forming two, in proportion to the plane of the actinopharynx, per- pendicular lamellae, the free edge of which are more or less strongly recurvated (figs. 132, 133). The middle part of the prolongation is built as the siphonoglyphe in its upper part, wliile the ectoderm of the perpen- dicular lamellae is longitudinally folded as in the actinopharynx, and of the same structure as that; the ectoderm of the recurvated part is smooth, but does not seem to differ in structure from that of the folded part. The boundary zone (fig. 132 a) and the folded part gradually become narrower aboraUy, and at last disappear (fig. 133). The stratum of nerve-fibrillae, the ectodermal longitudinal muscles and the structure of the endo- derm and the mesogloea agree with those of the actinopharynx. In the recur\-ated lamellae the endodermal muscles seem to be longitudinal, I cannot, however, decide it with certainty as my material has fallen short. Concerning the relation of the aboral prolongation to the filaments compare below! The number of mesenteries is that typical of Pcachia viz 6 pairs of perfect and 4 pairs of im- perfect mesenteries, the latter in the lateral and ventro-lateral exocoels. Among the perfect mesenteries the ventral directives are the stronger, the dorsal directives the weaker (always?). Below the actinopharynx the inner part of the pennons of the directive pairs is strongly curved towards the endocoels, in the other pairs towards the exocoels. The pennons of the perfect mesenteries are strong, with numerous high folds ACTINIARIA 103 Textfig. 128—133. Peachia hastata. Transverse sections of pennons ot perfect me- senteries in the repro- ductive tract (fig. 128, 130, 131) and in the cnido-glandular tract (fig. 129). In the figure 130 also an imperfect mesentery is reproduced (to the right). The pen- non in fig. 130 is from a ventral directive ; the pennon reproduced in fig. 131 is from the same section as the mesen- tery in fig. 130. Figs. 132, 133. Transversal section of the aboral prolongation of the si- phonoglyphe, fig. 132 in the upper, fig. 133 in the lower part. Both sections drawn under the same magnification a boun- dary zone chn ventral directives. Fig- 131 Fig- 133 Fig. 132 of very variable appearance. In the textfigure 130, a directive mesenterium and a mesenterium of the second cycle are sketched in the reproductive region, the text figure 128 shows a transverse-section of a perfect mesenterium in the vicinity of the sections reproduced above, and the textfigure 129 a perfect mesenterium in the region of the glandular tract (the last section has been taken from another individium having no reproduc- tive organs). Commonly the inner part of the pennons is more ramificated than the outer part. The lon- gitudinal pennons and the parietal muscles fuse together without distinct hmits. The part of the parietal muscles on the opposite side of the pennons is weak, distinctly definite, with the strongest folds on the inside. The mesenteries of the second cycle have produced small pennon-like formations, close to the insertions of the mesenteries. The inner parts of these formations are curved towards the exocoels, the parietal muscles are not particularly differentiated here. The parietal muscles are not spread over the column. 104 ACTINIARIA The mesenterial filaments are only present on the mesenteries of the first order. The ventral direc- tive pairs are, however, devoid of ciUated streaks. Below the aboral prolongation of the siphonoglyphe the filament namely begins as a weakly developed, single cnido-glandular streak of inconsiderable dimension, gradually growing thicker and attaining its largest dimensions in the reproductive region. As in certain Zoantharia (for instance Isozoanthus gigantcus) and in the Ceriantharia the ciliated streaks have probably here fused with the aboral prolongation of the siphonoglyphe and the actinopharynx, though the different parts of the filaments of the prolongation cannot be distinctly traced. Possibly the continuation of the sipho- noglyphe and the recurvated part correspond to the ciliated streaks, the folded parts to the cnido-glandular streak. The imperfect mesenteries are devoid of filaments. The ciliated streaks are of typical appearance. Only the mesenteries of the first cycle are fertile. The spe- cies is dioecious. The ovae are provided with a covering, decked by spines. L,arvae. (Synonymy and literature, compare Carl- gren 1906, p. 81). The larvae of tliis species, living on several hydroid- medusae, have been anatomically described before by my- self and by several other authors, wherefore I do not give any details of its anatomy here. The younger stadia with only 3 couples of mesenteries are disc-like (Carlgren 1906 fig. 6 a). Somewhat older stadia are a little more rounded, still older ones are more elongated and acuminated in the aboral end, only in the adult animal the body is cylindrical. The ex- terior aspect of the larvae in different stadia I have shown 1906 (textfig. 6). On the plate i, figs. 21—29 I have completed the series (all larvae sketched on the samef scale). The arrangement of the tentacles I have described before (1904). The first eight visible tentacles are distinctly seen on fig. 25, PI. i. On fig. 26 b, PI. i two of the younger tentacles are conspicuous. In the older larvae a three-lobed conchula little by little appears, which I have been able to state by feeding larvae during two months in an aquarium. A specimen dredged by myself on the clay (figs. 28, 29, PI. i) also had a three- lobed conchula, but only 10 tentacles. This reduced number of tentacles is associated with an abnormal development of the mesenteries (compare below!). The colour of the column of the older larvae was opaque- white, the shades of colour pretty well agree with those of figure 5, PI. 17 in the work of Had do 11 and Dixon (1885). Therefore I have no doubt at all that the larvae belong to Peachia hastata.With P. boeckii they cannot be identical as the colour of P. boeckii is another, and this species also in other respects is different from P. hastata. That only 3 lobes are developed in the larvae may be referred to the small size of the animals. Evi- dently these three lobes correspond to the three main lobes of the adult P. hastata which later on, as the ani- mal grows in size, develop a few or many secondary loljes. Concerning the appearance of the mesenteries, those of the 5tli and 6th couples seem to originate in the typical places, so that the former form pairs with the dorso-lateral, the latter with the ventro-lateral Textfig. 134. Peachia hastata. Transverse section of a yoniig anormal specimen. ACTINIARIA 105 " Edwardsia-mesentenes." In connection with the appearance of the tentacles these couples arise much nearer to the lateral "Edwardsia-mesentenes" than it is otherwise commonly the case in the Actiniaria. An older larva, sectioned in series, shows no filaments on the 6th couple and weak filaments on the 5th couple ; the filaments of the dorsal directive mesenteries were a little longer than those of the 5tli couple ; the ventro- lateral "Edwardsia-mesentenes" were provided with the longer filaments; the dorso-lateral "Edwardsia- mesentenes" had a little stronger filaments than the dorsal directives. The length of the filaments of the ventral directives was about equal to that of the dorso-lateral " Edwardsia-n:iesentenes" , but the former filaments reach about as far down as those of the ventro-lateral "Edwardsia-mesentenes." The abnormally developed specimen with only 10 tentacles, of which I give a transverse-section through the region of the actinopharynx (textfig. 134), had only 10 mesenteries. On one side of the direc- tive plane the mesenteries were typically developed, on the opposite side one pair was totally missing. The mesenteries marked with x are provided with weaker filaments than the other mesenteries. The strongly ciliated boundary streak between the siphonoglyphe and the actinopharjmx, occurring in adult specimens, is not distinctly diflferentiated here. Peachia boekii (Dan. & Koren.) Hadd. PI. I. Fig. 30. Siphonactinia Boekii n. sp. Danielssen and Koren 1856, p. 88, PI. 12, figs. 4 — 6. — — Dan. & Kor., Milne-Edwards 1857, P- 236. Andres 1883, p. 320, fig. 8. Peachia — (Dan. & Kor.), Haddon 1887, p. 475. Mc. Murrich 1915, p. 969. Diagnosis: The nematocysts in the column 14—17 X (1,5)— 2 //, in the tentacles 19—29 X 2—2,5 fi, in the acrinopharynx 24—26 X 3,5—4 /i. The spirocysts of the tentacles 14 x 1,5— 26 X 2,5 fi. Longitudinal muscles of the tentacles ordinarily developed. Conchula with 3 rectangular, large, flat lobes, more or less pedunculate, according to the state of contraction. I^ongitudinal pennons very strong with very numerous, high and palisade-Hke, sparsely ramificated folds. Parietal muscles on the pennon-side strong with numerous, comparatively high folds, only slightly ramificated or not at all so; on the opposite side weak, consisting of few, rather high folds, not expanded upon the column. Oral and marginal stomata present. Colour: Column yellowish-brown with scattered brown spots. Tentacles brownish-yellow with brownish-red annuli. Conchula shining Uke mother of peari (Danielssen and Koren). Dimensions: Length of the body 2,5 cm, that of the tentacles i cm. Length of the conchula 0,9 cm (Koren & Danielssen). On the prescribed type-specimen the length of the tentacles was only 0,3 cm. Occurrence: Norway, Hardanger fiord 80 — 100 fms. (Koren & Danielssen). According to Grieg the tj'pe-specimen was dredged at Utne, at a depth of 376 fms. Exterior aspect: The column is cyhndrical. The only preserved specimen I have seen is furnished with longitudinal and transversal furrows, of which the latter have certainly arisen by the contraction of the animal. I have not observed any elevations of the ectoderm in form of papillae. The number of tentacles is 12. They are short, conical, sometimes a little longitudinally sulcated, probably in connection with the state of contraction, and, according to Danielssen, arranged in a single cycle. Probably there may, how- 14 The Ingolf-Expcdition. V. 9. io6 ACTINIARIA ever, be two cycles of tentacles as in other Peachia species. The little oral disc is provided with indistinct radial furrows. The actinopharynx is long and has numerous longitudinal furrows (PI. i, fig. 30). I cannot decide its length in proportion to that of the column, as the proximal part of the specimen was torn off. The siphonoglyphe is very broad and smooth with well developed aboral prolongation. The conchula forms three rectangular, flat lobes (PI. i, fig. 30) which are longer than they are broad, and in the apex pressed a little in. On the figures of Danielssen and Koren (Fauna littoralis Norvegiae) it looks as if the conchula, in ex- tended state, would be pedunculate; in the preserved specimen the conchula has no such appearance, but the basal part of each specimen is built as in other threelobed Peachia- species. Anatomical description: Only the distal part of the type-specimen being left, and this piece not being well preserved, I cannot give any complete description of the anatomy of this species. The nematocysts in the ectoderm of the column are numerous and 14 — 17 X (1,5) — 2 n in size, those of the tentacles are still more numerous, 19 — 29 n long and 2 — 2,5 (i broad, so are also the spirocysts, reaching a size of 14 x 1,5 — 26 x 2,5 ji. The nematocysts of the acti- nopharj'nx are 24 — 26 « long and about 3,5 — 4 ^ broad. In all nematocysts the basal part to the spiral thread is visible. The nematocysts of the actinopharynx are broader in the basal end, the others of equal breadth. The siphonoglyphe is devoid of stinging capsules. The longitudinal muscles of the tentacles form rather high folds, arranged like palisades. The sipho- noglyphe is furnished with ectodermal longitudinal muscles which are wanting in the other part of the actinopharynx. The arrangement of the mesenteries is probably like that of other Pe«t7n'rt-species. As I have wished to save the specimen I cannot, however, give any exact informations con- cerning the arrangement of the mesenteries. The pennons recall those of other Pcachia- species; the folds are ver\- high and numerous, arranged like palisades and only a little Textfig. 135. ramificated (textfig. 135, transverse-section of a perfect mesentery in the lower part of the Peachia boekii. Compare the text, actinopharynx). The parietal muscles on the pennon-side were well developed, those on the opposite side of the pennons, on the other hand, not strong, and containing only a few folds, some of which are rather high. A small oral stoma and a large marginal one are present, at least on the stron- ger mesenteries. The mesogloea of the column was very thick, in proportion to that of other P^ac/iia-species ; this fact is possibly connected with the strong contraction of the animal. Genus Haloclava Yerr. Diagnosis: Halcampoididae with a well developed, rounded aboral body-end, physa probably not perforated by apertures. Column cylindrical with 20 longitudinal streaks of ampullaceous papillae in the distal part; indistinctly divided into regions, without spirocysts and sphincter. Tentacles 20, in the apex hemispherically swollen, forming acrospheres. Inner tentacles a little shorter than outer ones. A single ven- tral siphonoglyphe well differentiated and provided with a well developed (always?) aboral prolongation. ACTINIARIA jo„ Oral part of the siphoiioglyphe without a conchula. lo pairs of mesenteries (6 + 4 lateral and ventro-lateral), aU perfect and fertile. Parietal muscles distinctly differentiated from the longitudinal pennons. Spirocysts in the tentacles and the oral disc absent. This genus, proposed by Verrill for species of Eloactis with ampullaceous papillae on the column, while the true Eloactis are devoid of such, is nearly related to Peachia and especially to Eloactis. From the latter it is distinguished only through the above-mentioned character. The column of Eloactis has no ampulla- ceous papillae, but is a little otherwise differentiated (compare Eloactis). Attention is called to the fact that I have not found any spirocysts neither in Haloclava nor in Eloactis. Although this genus is not represented in the Arctic and Northern seas, nor has been dredged during the Ingolf-Expedition, I have nevertheless added it here for the sake of comparison with Eloactis. The type- specimen was found at the Eastern coast of the United States. Haloclava producta (Stimps.) Verr. Actinia producta n. sp. 5timpson, 1856, p. 100. Halcampa producta, Stimps. Verrill, 1862, p. 30, PI. i, figs. 10, 11, 1874, p. 330, 738. Andres, 1883, p. 318. Mc. Murrich, 1891, p. 136, PI. 9, figs. 2, 3. Corynactis albida n. sp. Agassiz, 1859, p. 24. Halcampa albida Agass. Verrill, 1862, p. 29, 1863, p. 57, 1866, p. 338, Andres, 1883, p. 318, Verrill, 1899. P- 41- Eloactis producta (Stimps.). Mc. Murrich, 1893, p. 141 — 143. Parker, 1900, p. 750, fig. 4. Hargitl, 1914, P- 245- Haloclava producta (Stimps.). Verrill, 1899, p. 41, fig. 7. Diagnosis: Typical nematocysts in the column 17 — 22 X 2 — 2,5 [i, in the acrospheres of the ten- tacles 48 — 106 X 2 n, in the other part of the tentacles 13 — 17 X 2 /«, in the actinopharynx 36 — 46 X 3,5 fi, and in the acrospheres nematocysts with discernible basal part to the spiral thread 72 — 98 X 3,5 — 4 /i. Ectodermal longitudinal muscles in the peduncle very strong. I^ongitudinal pennons of the mesenteries in the reproductive region rather strong, in transverse-sections reniform, with few, about 10 very ramificated, high folds, aU of about equal length. Outer lamellar part of the mesenteries attached close by the outmost end of the pennons. Parietal muscles rather strong, with somewhat numerous, low but ramificated folds, extended in radial direction (small but high), not expanded upon the column. Marginal stomata present. Colour: Column transparent, yeUowish-green (Stimpson). Column whitish, shading off into pale sal- mon, the base translucent with a bluish tint. Tentacles with brownish, knob-like tips (Hargitt); var. albida: Column pale brownish-yellow, tentacles paler, the knobs at the tips dark brown (Verrill). Dimensions in expansion: length 8 or 10 inches; in contraction: about 3 inches, diameter 0,75 inch. (Verrill). The largest preserved specimen, dissected by myself, was 2,5 cm long, largest diameter of the body 0,85 cm, smallest diameter 0,45 cm, length of the tentacles 0,3 cm. Occurrence: Eastern coast of the United States from South Carolina to Cape Cod (Verrill), Fort Johnson S. C. Sandy mud, near low-water mark (Stimpson) Woods Hole. — Buzzards bay, Catania bay 14* jQg ACTINARIA and in other places about Martha's Vineyard (Hargitt) var. albida. Long Island Sound, shores of Nan- tucket, Martha's Vineyard, Cape Cod. — The specimens examined by myself are from Woods Hole (Mc. Murrich) and from Newport (U. S. F. C.) Exterior aspect: The proximal part is smooth, and according to the state of contraction, rounded physa-shaped or more flat. Whether it is perforated or not, I cannot with certainty decide as the physa was rather contracted. In sections through a part of the physa I have not found any apertures. The column is cylindrical, elongated and provided with 20 distinct longitudinal furrows, corresponding to the insertions of the mesenteries. The distal part of the column has 20 longitudinal rows of ampuUaceous papillae, each row placed exactly between two insertions of the mesenteries. The rows are not all of the same length. On the parts of the column, adjacent to the 4 lateral endocoels of the first order and the ventral directive endo- coel they are longer than the rows, issuing from the dorsal directive compartment, the endocoels of the second order and the 2 exocoels being next to the dorsal directive endocoel. The remaining exocoel-rows are the shorter and composed of the lesser number of papillae. This arrangement is not always distinct, at any rate the rows belonging to the exocoel-parts of the column seem to be shorter than the other rows. The papillae are larger in the distal part than in the more proximal part; in other words, the papillae originate at the distal part, continuing towards the proximal part. The tentacles are 20, short, cylindrical, in the apex hemispherical, in certain states of contraction the distal end is knob-shaped. The 10 inner tentacles are a little shorter than the outer ones, and jaroceed from the endocoels (compare Carlgren, 1904, p. 542). The oral disc is of comparatively small diameter. The entrance to the siphonoglyphe is very distinct, though by far not so deep as in Peachia; its aboral pro- longation is rather long. The actinopharynx is short with numerous longitudinal folds and furrows. Anatomical description: Mc. Murrich (1892) has described some anatomical details of this species, but an anatomical examination of all organs has not yet been undertaken. The three layers of the column are all of about the same thickness and of ordinary height. The ecto- derm contains numerous typical nematocysts, 17 — 22x2 — 2,5 ji in size, and numerous mucus- and albumen- cells. In the ampuUaceous papillae, which are only evaginations from the body-waU, the ectoderm is a little differentiated from the other parts of the column (textfig. 136, longitudinal section through a piece of the column with a papilla). The mucus-cells namely decrease in number towards the apex of the papillae, while the nematocysts increase a little. The main-part of the ectoderm in the apex of the papillae consists of supporting cells. The some- what more numerous nematocysts in the apex indicate tliat we have to do with weak batteries of nemato- cysts. The mesogloea of the column is of a fibrillary structure and contains numerous cell-nuclei. The cavity of the papillae is rather large and in connection with the coelenteron through a narrower canal. In the papil- lae and in the communicating canal the circular muscles are very weak and form no folds, in the other parts of the column the circular muscles have high folds, which are, however, but slightly ramificated. No differ- entiated sphincter present. The acrospheres in the apex of the tentacles (fig. 137 uppermost part) differ considerably in struc- ture from the other part of the tentacles, the stalk or peduncle, in as much as the ectoderm is of quite another ACTINIARIA 109 character, the muscle-layers almost all waning, and the mesogloea and the endoderm attenuated. The ecto- derm of the acrospheres is very liigh, in comparison with the thin mesogloea and the endoderm. It contains large nematocysts, most densely packed, arranged like paHsades, of equal width and of variable size, from 48 to 106 -X 2!i, occupying almost the whole height of the ectoderm. Besides these, there are a little broader nematocysts with visible basal part to the spiral thread, 72—98 x 3,5—4 fi in size. The ectodermal and the endodermal muscles are absent or represented by very few muscle-fibrillae. The stalk of the tentacles is of another structure (fig. 137 lower part). The ectoderm is thinner than in the acrospheres and of about the Fig- 137 Textfigs. 136 — 139. Haloclava producia. Fig. 136: Longitudinal section through part of thi- cohiniu with papilla. Fig. 137: Longitudinal section of the distal part of tentacles with acrosphere. Fig. 138: Transverse section through part of a tentacle. Fig. 139: Transverse section of a mesentery in the reproductive region. Fig. 138 '"' •' longitudinal muscles; cm: circular muscles. same thickness as the mesogloea, the folds of the mesogloea included. It contains gland-cells and numerous, but small nematocysts, 13 — 17 X 2 /^ in size. The ectodermal longitudinal muscle-la3'er is very strong with densely packed, high folds (textfig. 137 Zm; textfig. 138, transverse-section through a piece of the basis of a tentacle), which are sometimes not ramificated, sometimes near the basis bifid or trifid. The main lamella of the mesogloea is thin, fibrillary with rather few cells. The endoderm is of about the same thickness as the ectoderm, the endodermal circular muscles somewhat strong, through the folds are rather large. The ectoderm of the oral disc and of the tentacles is devoid of spirocysts, the nematocysts are somewhat sparse and of the same size as in the stalk of the tentacles. In maceration-preparations I also found nematocysts resembling those of the actinopharynx. As the specimens were very much contracted in the region of the oral disc, it is, however, possible that these nematocysts in reality belong to the actinopharynx. The radial muscles were considerably weaker than the longitudinal muscles of the tentacles. The ectoderm of the actinopharynx is much higher than the endoderm, and several times thicker than the mesogloea. It ACTINIARIA contains numerous mucus- and gland-cells, and nematocysts, 34 — 46 X 3,6 ft in size. The longitudinal muscles are very weak and here and there absent? The ectoderm and especially the endoderm of the siphonoglyphe are thickened, the gland-cells and the nematocysts of the ectoderm very sparse, the longitudinal muscles very weak. The nerve-layer of the actinopharynx is rather distinct. The mesenteries are 20 ^ in number, namely 6 pairs of the first order and 4 pairs of the second, the latter placed in the lateral and ventrolateral primary exocoels as in Pcachia and Eloactis. The four couples of the first order arising after the " Edwardsia-stage" , viz. the fifth and sixth couples, are weaker than the outer couples of the first cycle. All mesenteries are perfect, those of the first cycle coalesced with the actino- pharynx in its whole length, the mesenteries of the second cycle are inserted upon one half of the actino- pharynx. The ventral directive mesenteries are the stronger, the mesenteries of the second order the weaker. The longitudinal muscle-pennons are kidney-shaped in transverse-sections through the reproductive region and well Hmited from the parietal muscle, in contradistinction to what occurs in Peachia. The folds of the muscles are high but few, about 10, richly ramificated even from the basis (textfig. 139 transverse-section through a mesentery in the reproductive region) and all of about equal height. The figures of the mesente- ries reproduced by Mc. Murrich (1892, figs. 2, 3) are of a young specimen. The lamellar part of the mesen- teries issues near the outside of the pennons. The parietal muscles are well developed with low, but nume- rous and ramificated folds spread over a comparatively large area of the mesenteries, whereby the folds become narrow and high. The parietal muscles are not expanded upon the body-wall. The mesenterial fila- ments are of the usual appearance; the ciliated streaks are narrow, the intermediate streaks provided with extraordinarily numerous gland-cells. The mesogloea of the filaments contains sparse cells. Oral stomata are probably absent, but marginal stomata present. They are large and irregular, and arranged with one in each mesentery in about the middle line of the mesenteries, a little below the tentacles. The animal is dioe- cious. The more closely examined specimen was provided with ovaria on all mesenteries. The egg-cells show a fine-grained ectoplasma and a coarse-grained endoplasma. As in Pcachia and certain other Actiniaria the eggs are provided with a spinous covering. A "nutrition"-apparatus is developed by distinct invaginations of the endoderm extending towards the egg-cells. Genus Eloactis Andr. Diagnosis: Halcampoididae with a well developed, rounded aboral body-end, physa, perforated by numerous apertures in 20 longitudinal rows. Column cylindrical; with numerous low, not anipullaceous but sohd papillae, scattered over the whole surface; not distinctly divided into regions; without spirocysts and sphincter. CincHdes in the uppermost part of the column. Tentacles as in Haloclava. Actinopharynx as in Haloclava with longer or shorter aboral prolongation. No conchula. Pairs of mesenteries as well as their muscles as in Haloclava. Tentacles and oral disc without spirocysts. ^ Hargitt (1914) points out that the mesenteries are hexamerous in j-oiing specimens, decamerous in older ones, and from this he concludes that the arrangement of the mesenteries "can hardly be of great significance as a toxonomic feature". As the ani- mal during its development passes through a hexamerous stage with 6 pairs of mesenteries of the first cycle, it is evident that this „variation" in the arrangement of the mesenteries is of no importance to the diagnosis. The adult specimens are namely decamerous. ACTINIARIA jjj Eloactis mazelii (Jourd.) Andr. PI. I. Fig. I. Ilyanthiis mazelii, ii. sp. Jourdan, 1880, p. 41, PI. 2, fig. 5. Anemonactis magnifica, 11. sp., Andres, 1880, p. 329. Eloactis mazelii Jourd., Andres, 1883, p. 465, PI. 8, figs. 4—7, fig. 39. Faurot, 1893, p. no, PI. i, fig. 4, PI- 5. figs. I, 2. Garstang, 1892, p. 380. Walton and Rees, 1913, p. 68. Rees, 1913, p. 70, textfigs. I — 4. Diagnosis: Nematocysts in the ectoderm of the column 26— 29x2,5 ^, in the acrospheres 120 — 202 X about 4 //, in the peduncle of the tentacles 20 — 24 X 2,5 fi, in the actinopharj^nx 53 — 65 X $ [i. Longi- tudinal muscles of the peduncle of the tentacles strong. Pennons of the mesenteries in the reproductive region ver>' strong with numerous (about 30) folds, high, rather nmch ramificated and almost all of about equal length. Outer lamellar part of the mesenteries attached to the pennon near the outside. Parietal muscles strong, provided in the outer parts with low, in the inner parts with comparatively high and a little branched folds; not expanded upon the column. Colour: reddish-orange, physa paler, tentacles white with brown tips, oral disc orange with darker radial streaks (Jourdan) (yar. rubra compare Andres, 1883, p. 465). Flesh-coloured tint, tentacles marked with brown near the apex, oral disc orange-pink with somewhat paler rays (Walton and Rees). Body- wall orange, tentacles blotched with brown at the apex, several tentacles had purphsh, double stripes on the inside, others appear to have only one coloured stripe (Orton). Column white, shading off into yellow. Tentacles white, shading off into flesh-colour or yellow, provided with numerous, irregular, reddish-brown spots increasing in number in the uppermost part of the peduncle, and with small opaque white spots. Oral disc of the same colour as the tentacles with 20 opaque, white tongues turning towards the mouth (spec- imens from Naples, Carlgren). Column shading off into brown, tentacles uncoloured (Appellof). Dimensions: Height of the body unto 8 cm, breadth 5 cm, length of the inner tentacles 3,5 cm, length of the outer ones 6 cm (Andres). Occurrence: Norway. Hjalte fiord 40 — 50 fms (Appellof) i small specimen. Further distribution: The Mediterranean. Gulf of Marseilles 60 — 80 m (Jourdan). Naples (Andres). England. Devonshire coast (Garstang). South Devon Coast, Eddy- stone (Walton and Rees). Exterior aspect: The proximal body-end is rounded, forming a physa which is, however, not di- stinctly limited from the other part of the column. The physa is perforated by numerous, radially arranged apertures as in Peachia. The rows correspond in number to the mesenteries. In a large specimen from Naples I have observed more than 10 apertures in each row. The shape of the body is cj-lindrical or more ovoid, according to the state of contraction, and provided with 20 distinct longitudinal furrows, corresponding to the insertions of the mesenteries. On the surface there are numerous, close, flat elevations in scattered groups and of variable size, very distinct in extended specimens, but difficult to discoA'cr in contracted ones, as the column of such specimens is very wrinkled. In the uppermost part of the column there are some few 112 ACTINIARIA cinclides. I have obsen'-ed cinclides on sections (compare below) as well as on living specimens in Naples. They are, however, irregularly placed; in some chambers I have found one or several apertures, in other cham- bers none. By an injection with methylen-blue the colour was squeezed through the cinclides. The tentacles are 20 in number in typical specimens, and in extended state rather long. The inner tentacles, belonging to the endocoels, are shorter than the outer ones, the exocoel-tentacles, (compare Faurot, 1895 and Carl- Textfigs. 140 — 143. Eloaciis ma:elii. Fig. 140: Longitudinal .section through part of the cohimn with .solid papilla. Fig. 141: Transverse section through a cinclid in the most distal part of the column. Fig. 142: Transverse section of a yonng specimen in the actinopharynx tract. Fig. 143: Transverse section of a mesentery in the reproductive region. cm: circular muscles. Fig. 142 gren, 1904, p. 542). They are cylindrical with hemispherical, smooth apices, while the main part of the ten- tacles, the peduncle, is provided with flat elevations like those found on the column. The oral disc is not wide, but smooth and provided with distinct radial furrows, corresponding to the insertions of the mesen- teries. A well developed ventral siphonoglyphe is present. There is no conchula or tongue-shaped formation at the entrance of the siphonoglyphe. Its aboral prolongation is inconsiderable in comparison with that of Peachia. The other part of the actinopharynx is provided with numerous longitudinal furrows and com- prises about one third of the length of the body. Anatomical description: Rees (1913) has described the anatomy of this species; but his exa- ACTINIARIA 113 mination is in several points incomplete. The ectoderm of the column is high and contains numerous mucus- and sparse albumen-cells. In the central part of the elevations the mucus-cells are still sparser, while the main part of the cells is formed by supporting cells and numerous nematocysts which latter are rather sparse in the other part of the column. The nematocysts are 26 — 29 X 2,5 fx in size. The elevations thus may be regarded as weak batteries of nematocysts as in Haloclava, though they are not ampullaceous as in this genus, but compact and supported by an off-shoot of the mesogloea (textfig. 140) . The cinclides and the apertures of the physa are of the same structure. The ectoderm as well as the endoderm are invaginated, and the aper- tures are surrounded by rather strong circular muscles belonging to the endodemi (textfig. 141). The meso- gloea of the column is thicker or thinner than the ectoderm, according to the different state of contraction. It is fibrillary and contains rather numerous cells with a scanty amount of protoplasm. The endodermal circular muscles are very strong and form palisade-shaped folds, not concentrated so as to form a sphincter. Strong parts of these muscles, as usual, break through the mesenteries. The uppermost part of the tentacles, the acrospheres, are, as in Haloclava, of another structure than the other part of the tentacles, the peduncle. The ectoderm is very high and provided with very numerous nematocysts with slightly visible basal part to the spiral thread. They reach a size of 120—202 X about 4 11, and are rib-like. The tentacles, as well as all other parts of the animal, are devoid of spirocysts. The nerve-layer is distinct, the ectodermal muscles very weak. The mesogloea contains rather numerous cells, poor in protoplasm, and it is about half or one third as thick as the ectoderm. In the mesogloea I have observed fibres, now straight, now folded, now run- ning along the tentacles, now in transverse direction and terminating partly in the endoderm, partly in the ectoderm, apart from the nerve-layer. I cannot with certainty decide the nature of these fibres, but it is not very probable that they are nerve-fibrils, as they are much tliicker than such fibrils ; I am more incUned to think that they are nematocyst-threads having been thrown into the tissues of the animal by the ejec- tion of the nematocysts, on account of an abnormal position of certain nematocysts. The endoderm is of about the same thickness as that of the mesogloea. The main part of the tentacles, the peduncle, is provided with a rather liigh ectoderm, containing numerous mucus-cells and sparse albumen-cells. The nematocysts display an indistinct basal part to the spiral thread and reach a size of 20—24 X 2,5 [i. The nerve-layer is well developed, so are also the longitudinal muscles, the folds of which in transverse-sections are dichoto- mously branched and of about the thickness of the ectoderm. The mesogloea is of the same structure as in the apex and attenuated towards the base. The ectoderm of the oral disc is of ordinary height and contains sparse nematocysts with indistinct basal part to the spiral thread, 17—19 X 2 ^ in size. Their ectodermal muscles recall those of the peduncle of the tentacles. The mesogloea and the endoderm are thin. The ecto- derm of the actinopharynx is very high and provided with numerous, rib-Uke nematocysts, 53—^5 X 5 n in size, and long, close albumen-cells. Their mucus-cells are sparse. The ectoderm is much higher in the ridges than in the furrows. The ectoderm of the siphonoglyphe is also very high, provided with smaller albumen- cells, but devoid of nematocysts. There is no such strongly ciliated boundary streak to be found here as in Peachia (compare p. 102). The nerve-layer is rather distinct in the actinopharynx. There are also ver>' weak ectodermal longitudinal muscles. The mesogloea and the endoderm arc thin in the actinopharynx, in the siphonoglyphe however tliick. The iDgolf-Expedition. V. 9. -^ ACTINIARIA 114 There are 10 pairs of mesenteries, two of which are directives; the ventral pair is connected with the siphonoglyphe ; all mesenteries are perfect and fertile. The longitudinal pennons (fig. 143) are very strong and in the reproductive region provided with about 30 high, dichotomously branched folds, most of which are of about equal height; the inner and the outer parts of the pennons are almost equally developed. The parietal muscles (fig. 143) are well differentiated, in their inner part either transversally expanded or in the lower part of the reproductive region more thin but longer. The outer part of the parietal muscles is weak and not expanded upon the body-wall. The part of the parietal muscles corresponding to the parieto-basilar muscles is sharply indicated, and a deep fold separates it from the mesogloeal main lamella of the mesen- teries. Sometimes the mesogloea of both sides of this fold is coalesced, so as to form meshes in transverse- sections, a structure recalling that of the parieto-basilar muscles of for instance Stomphia. The ciliated streaks are also found on the ventral directives what is not the case in Peachia. The median streak of the filaments are provided with numerous, small, rib-like nematocysts, about 14 — 17 X 2 11 in size; large nematocysts are very sparse. In the cnido-glandular tract, on the other hand, large nematocysts are more common; they are partly 58 — 67 X 6 fi, partly 68 — 79 X 4 // in size. Besides these, there are small nematocysts as in the median streak. The intermediate streak is well differentiated and provided with numerous gland-cells. The mesogloea of the filaments contains sparse ceUs. There is a very large marginal stoma in each mesentery. The oral stoma is rather large. The specimen is dioecious. Description of a young specimen: The specimen, dredged in Hjiilte fiord, was not sexually ripe and differs in some points from the adult specimens. Its length was 1,5 cm, the largest breadth 0,25 cm, and the length of the tentacles about 0,2 cm. The exterior of this specimen is shown on the figure i, PI. i. The physa was ampuUaceous, the elevations of the column distinct, especially in the distal part. The visible tentacles were 11; as there are 12 mesenteries it is probable that one more tentacle is present, though involved; I cannot, however, decide it as I have not sectioned the distal part. The aboral prolongation of the siphono- glyphe was rather well developed. In order to make an anatomical examination of tliis specimen I have cut out a piece about 0,6 cm long, encluding the lower part of the region of the actinopharynx and a part below this region. The text- figure 142 shows a transverse-section through the lower part of the region of the actinopharynx. The sipho- noglyphe is, seemingly, well developed, the albumen-cells are rather numerous, the endoderm of the sipho- noglyphe is high, and, in contradistinction to the other endoderm of the actinopharynx, it is of a bladdery structure. The elevations of the column were not as distinctly differentiated as in the sexually mature spec- imens. The perfect mesenteries were 12 in number, namely 6 pairs. In a lateral exocoel one pair of weak imperfect mesenteries rose slightly over the surface of the column ectoderm. The lateral mesenteries of the second order thus arise earlier than the ventro-lateral mesenteries, in other words, the development of the mesenteries of the second order proceeds in a dorso-ventral direction, though the dorso-lateral mesenteries are suppressed. The fifth and the sixth couples of mesenteries arise as in Halcampa, the ventro-lateral couple thus being the weaker. None of these couples reach the undermost part of the actinopharynx. The longi- tudinal pennons are weaker than in the sexually ripe specimens. The folds are only slightly branched, in the lower part of the actinopharynx they are about 10 in number, below the actinopharynx a little more ACTINIARIA J J numerous, unto 15. The pennons vaty in appearance, but their inner and outer parts look almost alike. The parietal muscles are weaker than in the adult specimens and more elongated. The ciUated streaks are not developed on the directives, but they are present on the 4 other pairs of the first order. Genus Siphonactinopsis n. gen. Diagnosis: Halcampoididae with the basal end rounded. Column cylindrical, of considerable length, smooth, without " Halcampa-papillae" , not divisible into regions, without spirocysts and sphincter. Ten- tacles short, conical, 40 in number, not bulbously swollen in the apex, the inner tentacles longer than the outer ones. OiJy one, a ventral, siphonoglyphe, not elongated below the actinopharynx. Conchula absent. Pairs of mesenteries 20 (10 + 10) all perfect and fertile. 2 pairs of directive mesenteries. Parietal muscles a little differentiated. Siphonactinopsis laevis n. sp. PI. 2. Fig. 9. Diagnosis: Ectodenn of the column with nematocysts, about 17 — 20 [i long, densely packed just below the tentacles. Ectoderm of the tentacles with numerous spirocysts about 36 — 38 X 5 // in size and with numerous nematocysts (22—29 X 2/i). Longitudinal muscles of the tentacles well developed, with palisade-shaped folds. Nematocysts of the actinopharynx partly typical, 28 x 3—4 // in size, partly broader in the basal end and with distinct basal part to the spiral thread (length 24, breadth 5 //). Pennons of the mesenteries strong, in transverse-sections of considerable length with rather high, branched folds; as these folds are of equal height they make the pennons look like combs. Outer part of the mesenteries issues from the pennon in its most external parts. Parietal muscles not strong, consisting of low, though closely packed, a Uttle branched folds, not expanded upon the column. Marginal stomata large. Well developed ciliated streaks. Colour? Dimensions: in contracted state, length 5,5 cm, breadth unto 2,5 cm, inner tentacles i cm long, outer tentacles about 0,5 cm. Occurrence: Greenland? without distinct locality. (Habitat questionable!) i sp. Exterior aspect: The state of preservation was rather good, wherefore I can give a fairly suffi- cient description of the organisation. The greater part of the ectoderm of the column was, however, lost. The proximal part of the animal is rounded and involved. The elongated column shows no sign of being divided in regions and is devoid of papillae and other off-shoots. In consequence of the strong con- traction the column is deeply transversely furrowed, while the insertions of the mesenteries on the outside are indistinctly marked. The distal end of the column is in certain places crenelated. Whether these crene- lations are a normal feature or only due to the contraction I cannot decide, as this part of the animal was not well preserved. No distinct fossa is present. The tentacles are 40 in number, probably arranged in three cycles. As some of the tentacles are invaginated, it is, however, difficult with certainty to ascertain this ar- rangement. They are short and conical, the inner tentacles almost twice as long as the outer ones. The oral disc is rather small. There is no distinctly marked entrance to the siphonoglyphe. The actinophar>'nx is 15* ii6 ACTINIARIA Textfigs. 144—145. Siphonaclinopsis laevis. Fig. 144: Transverse section of mesentery in the reproductive tract. Fig. 145: Transverse section of the outer part of a mesentery. well developed, almost as long as half the length of the column or, at any rate, more than one third of it, and provided with numerous liigh folds. Only one siphonoglyphe is present at the ventral directives, it is distinguished from the other furrows in the actinopharynx by its larger breadth and shows no aboral pro- longation. Anatomical description: The proximal part of the column is — as far as I can see — of usual structure. In the very few fragments left of the ectoderm of the column I have found very sparse nema- tocysts, about 14 — 17 /z in length. Just below the tentacles and above the crene- lations on the column fragments of the ectoderm were left. In these fragments I observed closely packed nematocysts and very sparse spirocysts, the latter possibly belonging to the ectoderm of the tentacles. These nematocysts were a little larger (17 — 20 [i long) than those of the other part of the column. Pos- sibly we here have to do with pseudo- acrorhagi, the occurrence of which can- not, however, be added to the diagno- sis, until it has been stated on better preserved material than mine. The cir- cular muscles of the column are weak and form no sphincter. The ectoderm of the tentacles contains numerous spi- rocysts, 36 — 38 X 5 //, and nematocysts, 22 — 29 X 2 ;u in size. The longitudinal ectodermal muscles are well developed, with palisade-shaped folds. The oral disc is of the same structure as the ten- tacles, the nematocysts are, however, sparser. The ectoderm of the actinopharynx is of ordinary thickness and much tliinner than the mesogloea. The granular gland-cells are very numerous, the typical nemato- cysts less so and about 28 X 3 — 4 fi in size. Besides these, there are here nematocysts with disceniible basal part to the spiral thread. They are about 24 fi long and 5 fi broad in their broadest end. I have here and there found a spirocyst of the same size as that of the tentacles. The nematocysts and the gland-cells are much sparser in the siphonoglyphe than in the actinopharynx. The mesogloea of the column and of the other parts of the body is rather thick. The mesenteries are arranged in 20 pairs (10 + 10), of which 2 are directive mesenteries. All mesen- teries are perfect, fertile and coalesced with the actinopharynx in its whole length. It is difficult to decide ACTINIARIA jj- whether a pair of mesenteries belongs to an older or a younger cycle, because all pairs of mesenteries and often also both mesenteries of one pair are differently developed, as regards the muscle-pennons. The lon- gitudinal muscles of the pennons are strong, in transverse-sections elongated with numerous (about loo) close folds, almost all of about equal height, whereby the pennons in transverse-sections get a comb-like appearance. The main lamella of the mesogloea is tliickened in the outer part of the pennons, in the inner part thin. The outer, more lamellar part of the mesenteries is attached to the outside of the pennons. The inner part of the pennons is on the directive mesenteries curving towards the endocoels, on the other mesen- teries towards the exocoels (textfigure 144. Transverse-section through a mesentery in the reproductive region). The parietal muscles are comparatively weak, with rather low folds, smooth or a little ramificated, especially on the side of the pennons. On the opposite side they are, however, more high and a little more richly branched (Fig. 145. Transverse-section of the outer part of a mesentery). The}- are not expanded on the column. No basilar muscles present. As far as I can see the oral stomata are also lacking. A large stoma, probably a marginal stoma, is visible on the mesenteries, aside from the pennons, rather near the upper end. The mesenterial filaments are very long and extended almost to the proximal end of the animal. The ciliated streaks are well developed. The mesogloea of the filaments is thick and contains few cells, poor in protoplasm. Inside the parietal muscles the mesogloea is very much thickened. Family Halcainpidac. Diagnosis: Athenaria with commonly elongated, cylindrical body, with a simple or double meso- gloeal sphincter, without acontia. Column divided or not divided in regions. Perfect mesenteries 8 to 12 (or more?). Ciliated streaks present, sometimes discontinuous. Concerning the arrangement of this family, its designation and the genera, which, according to nie, belong to it, compare p. 19, 21, 22. The type of the genus Halcampa, after which the family is named, has, as I suggested (1893, p. 37), and as I have shown (1900 b, p. 11 71), a mesogloeal sphincter, which Stephenson (1918, p. 9) has at length confirmed. Genus Halcampa Gosse. Diagnosis: Halcampidae with the column divisible into three regions, physa, scapus and capi- tulum. Physa ampullaceous with pores in one or two cycles. Scapus with papillae ("Ha/cam^a-papillae") to which grains of sand often adhere. Ectoderm of the capitulum with numerous spirocysts, with a well developed layer of nerve-cells and nerve-fibrillae, in the uppermost part with longitudinal muscles forming a prolongation of the muscles of the tentacles and of the oral disc, and probably belonging to these muscles. Sphincter comparatively weak, often close to the ectoderm and expanding a httle into the base of the ten- tacles. Tentacles 8 to 12, short, of equal width, with rounded apices. 2 rather sUght siphonoglyphes and 2 pairs of directive mesenteries. 8—12 perfect and 6—12 fertile mesenteries forming strong pennons, besides a more or less perfect second cycle of very weak, sterile mesenteries, never producing pennons, but expanded over almost the whole length of the column. & jjg ACTINIA RIA The structure of the papillae, named by me " Halcanipa--pain]lae" has never been subject to a closer anatomical examination. In English and American literature they are simply called suckers, a name also used for several heterogeneous differentiations of the column. On closer examination the papillae of Hal- canifa duodecimcirrata are found to be completely differing in structure from the verrucae of Urticina and other Cribrinidae. To the scapus of Halcampa, Paraedwardsia and other forms provided with "Halcampa- papillae", greater or smaller numbers of grains of sand most often adhere. After having loosened the grains of sand we find on closer inspection that the ectoderm of the papillae is differentiated from the other parts of the scapus ectoderm. The figure 8, PI. 4 shows a transverse-section through a piece of the outer part of the sca- pus of Halcampa duodecimcirrata with a papilla (only the ectoderm (cc) and part of the mesogloea [me) are reproduced, the section is stained with iron-hematoxyline) . The ectoderm is rather high between the papillae, but considerably attenuated towards the papillae. The outer parts of the ectoderm cells contain numerous grains. In the papillae the ectoderm is wholly transformed. Between the mesogloea and the thick cuticle we see on the section bundles of fibres [ch), rather strongly stained, radially arranged and separated from each other by, as it seems, fairly large intervals. The fibres connect the mesogloea, forming off-shoots with the outer, darker part, the cuticle (c) ; they are not always distinctly limited from the mesogloea. The inter- vals are probabh^ only seemingly cavities, I have sometimes found several inter\^als to be more or less filled up by granular cells [gl.). I have also observed that these cells easily get loose and are torn off from their original position by sectionizing. As to the cuticle it is of a rather loose consistency, on account of its being stratified. The main part of the cuticle is strongly stained on the reproduced section, in the outer, more faintly stained part, we, however, observe that the cuticle forms several irregular lamellae, which stand out more distinctly when the cuticle is unstained. These layers are incrusted with foreign bodies [in). For the sake of comparison I here reproduce two sections through the scapus of Paraedwardsia sarsii and Scytophorus antarcticus. In both species the scapus is provided with a distinct cuticle which is tliicker in the papillae than in the other parts. The figure 7, PI. 4 shows a papilla of P. sarsii with adjoining parts of the skin. The section much recalls that of Halcampa. The cavities of the ectoderm are, however, smaller, the bundles of fibres thicker. The cuticle is incrusted with foreign bodies forming a ver>' thick layer in the papillae. The figure 6, PI. 4 representing a transverse-section of one part of Scytophorus antarticus looks a little different. The cavities are. large and contain cells, among others large mucus-cells (gl.), the bundles of fibres are shorter, and the mesogloea reaches further on towards the cuticle than in the other forms. In spite of this, there is no doubt that also here we have to do with " Halcampa--pa])i\lae" . How are we to explain these papillae? As far as I can see, these organs are secretory papillae, for which suggestion the circumstance also speaks that the grains of sand are not strongly attached to these papillae, while they are only with difficulty loosened from the verrucae (sucking warts) of for inst. Urticina. The secretion by which the grains are attached is, everything considered, formed by the granular cells en- closed in the intervals, while the fibrous bundles may be chitinized supporting cells, partly fused with the mesogloea. Among the specimens of Halcampa arctica I found a specimen without incrustations. I at first sugge- sted that this specimen did not belong to this species, but a closer examination of some sections proves that ACTINEARIA 119 there are traces of papillae. Fig. 5, PI. 4 represents a section through a part of the scapus, stained with car- min of borax. The ectoderm is high in the papillae and unaltered, or possibly only a little transformed. From the mesogloea off-shoots project, staining more intensely than the mesogloea itself (in the figure dark). On some folds of the ectoderm these off-shoots are transversely sectioned, in wliich case they show a circular arrangement. Though these paiDillae differ in structure from the typical papillae, I think that we also here have to do with " Halcampa-psipillae" . Unfortunately I have only a few sections which are even more than 20 3'ears old, and it has been impossible to make new preparations as only very little of the ectoderm of the scapus remains. For these reasons I cannot with certainty judge of the structure. It is possible that the sec- tion has Jiit the edge of the papillae obliquely, so that the ectoderm above the papillae does not belong to these latter; tliis is, however, not likely. Perhaps the structure of the papillae may be interpreted thus, that the primitive papillae have been lost, so that of the cliitinized ectoderm-cells, only the off-shoots, which are dark in the figure, have laeen left and the ectoderm has then regenerated to its full height. Halcampa duodecimcirrata M. Sars. PI. 4. Fig. 8. Edwardsia duodecimcirrata n. sp. Sars, 1S51, p. 142. — — Sars, Danielssen and Koren, 1856, p. 87. Danielssen, 1861, p. 45, I^iitken, 1861, p. 196. Meyer and Mobius, 1863, p. 70, PI. 3, figs. A-D. Andresi88o P- 137- Edwardsia Chrysanthellmn Peach., Mobius, 1S73, p. 100 (pro parte). Halcampa — — Schulze, 1875, p. 121, 140. Haddon, 1886, p. 5, 1887, p. 478, 1889, P- 335 (pro parte). Edwardsia liitkeni n. n. Andres, 1883, p. 308. Halcampa farinacca Verr., Andres, 1883, p. 314 (pro parte). — duodecimcirrata Sars, Carlgren, 1893, p. 38, PI. 5, figs. 1—5, PI. 6, figs. 1—2, textfigs. 6, 7. Diagnosis: Physa ampullaceous, capable of almost complete involution, with small elevations, perforated by 9 ( — 13?) apertures, one central and the others arranged in a circle around the central one. Nematocysts of the scapus 10—12 X almost i ji, those of the capitulum 11— 17 X 1—1,5 H. those of the tentacles about 12 X i /i. Spirocysts of the capitulum 14—19 X 1,5—2 /i, those of the tentacles 14—19 X almost I— I II. Tentacles 8—12. Nematocysts of the actinopharynx 27—34 X 3.5—4 1^. "f^en narrower in the distal end and with discernible basal part to the spiral thread. Perfect mesenteries 8—12. A more or less perfect cycle of the second order present. Longitudinal pennons of the mesenteries with comparatively few folds, 8—16 or a little more, only sUghtly branched. Parietal muscles and the nmscles of the imperfect me- senteries weak, of about the same appearance. Expansion of the parietal mucsles on the colunm consider- able. 8 to 10 (12?) perfect mesenteries fertile. Colour: Physa uncoloured, with small white spots. Scapus and capitulum pale flesh-coloured, the latter often pale brownish-red, especially in the distal part, and often provided with 8—12 white longitu- j^Q ACTINIARIA dinal stripes, terminating in a white spot below the tentacles, or with rows of spots instead of stripes. Ten- tacles more or less transparent, white or yellowish with 3 to 5 (6) transversal reddish-brown bands, the first band next to the oral disc M-shaped, the second V-shaped. Directive tentacles sometimes opaque white. Oral disc commonly yellowish with radial brownish-red stripes at the insertions of the mesenteries, around the mouth a brownish-red annulus, between the stripes i — 3 triangular spots. Sometimes the oral disc is opaque white without spots (Carlgren, 1893). Dimensions: In contracted state unto 4 cm long. Occurrence: The Baltic Sea. 6' S. to W. off Karlskrona (Kolmodin, 1882), E. oft' Simbrishamn 45 fms. (Gunhild-Exp., 1878), 25° E.N.E. off Hammeren (Hammerodde) 40 fms. clay (Kolmodin, 1882), N.N.E. off Gudhjem 38—40 fms. (Kolmodin, 1882), 7' E. to S. off Svaneke 38 fms. (Kolmodin, 1882), oft' Svaneke 47 fms. (Mortensen, 1895), 7' W.N.W. off Ronne 25 fms. (Kolmodin, 1882), 55°9' N. i3°49' E. 25 fms., 55°/ N. I3°3i' E. 25 fms., 54°57' N. I3°42' E. 25 fms. (Oberg, 1871), Kiel 7—10, 5 fms. (Meyer, Mobius, Schulze, Michaelsen). Hoh-wachterbucht 8,5 fms., W. off ^ro (Winther). The Sound (Moller, Ltitken, Hering, "Sven Nilsson" St. 27, 29, 30, 38, 41, 42, 46) KuUen (I^oven), Hellebaek (lyiitken, Mortensen). The Great Belt (Winther) W. off Refsnses 48 m (Mortensen, 1912), Konigshaff Alsen (Ahlborn), The Dittle Belt 7—24 fms. (Schiodte). Samso Belt (Winther). Cattegat (Petersen and others), Hirtsholm (Mortensen, 1897), S. off Morup reef (Gunhild-Exp., 1878), Marstrand fiord 15 fms. (1864), GuUmar fiord, Strommarne, Skatholmen (Carlgren, 1895), between Grasholmen and Gullholmen, N. Gaso fiord (Wiren, Carlgren), Bohuslan (I,oven), Vaderoarne (Arwidsson, 1895). Skagerrak, 4'/,, leagues S.W. '/i W. off Skagen lightship 60 fms. (Danish biological station 1904). Norway. Bergen (teste Sars), Drontheim fiord, Rodberg 5 — 10 fms. I-,ofoten Ure 20 fms. (teste Sars), 'Vadso 20 — 30 fms. (teste Danielssen). As I have before (1893) described the exterior appearance and the anatomy of this species I have not much to add now. The structure of the "i/fl/cam/)fl-papillae" has been discussed above. Concerning the relation of this species to Halcampa ardica compare the remarks to the latter species. Halcampa arctica Carlgr. PI. I. Figs. 3,4. — PI. 2. Figs. 14, 15. — PI. 4. Fig. 5. Halcampa arctica n. sp., Carlgren, 1893, p. 45, PI. i, figs. 1,2. PI. 5, figs. 6 — 12. Diagnosis: Physa ampullaceous, retractile, provided with a central aperture surrounded by two cycles of apertures. Nematocysts of the scapus 12 — 14 x 1,5 fi, those of the capitulum 12 — 16 x i — 1,5 /<; those of the tentacles 12—17 X 1,5 ^. Spirocysts of the capitulum 19—32 X 2—2,5 fi, those of the tentacles (13)19 X I — 36 (41) X 2,5- — 3/i. Tentacles 12. Nematocysts of the actinopharj^nx 24 — 41 x 3,5 — 5 ft of the ACTINIARIA J2I same appearance as in H. duodecimcirrata. Perfect mesenteries 12, imperfect 12. Longitudinal pennons of the perfect mesenteries very strong, with about 20—30 larger folds in the upper part of the reproductive region. The large folds have numerous secondary folds. Parietal muscles and the imperfect mesenteries of about equal appearance, mostly comparatively strong, in transverse-sections elongated with low, but rather numerous folds. Expansion of the parietal muscles on the column considerable. All perfect mesenteries fertile. Colour? Dimensions: Length unto 6 cm in contracted state, breadth unto 1,2 cm. Length of the tentacles unto 0,5 cm. Occurrence: West-Greenland, Godhavn (Andersen). Holstensborg 20 fms. (Holm 1884). Nordre Stromfiord (Nordmann). Jacobshavn 120 fms. (1870). Greenland without distinct locality. E. of Iceland, 64=25' N. I2°9' W. 211 fms. Temp, at the bottom 0,8° (Ingolf-Exp., St. 58). West Spitzbergen, Treurenberg bay 3 — 66 fms., Wijde bay 40 fms. (Sw. Spitzber- gen-Exp. 1861), Mosel bay 3 fms. (Sw. Spitzbergen-Exp. 1862), Bel Sound 5 fms. (Sw. Spitzbergen-Exp. 1861, Malmgren, 1864), Ice fiord Safe Harbour 30 fms. (Malmgren 1864), be- tween Coles bay and Green bay 4 m (Sw. Spitzbergen-Exp. 1908), Kobbe bay 3 fms. (1861). East Spitzbergen, Great Island 8o°i5' N. 30° E. 95 m. King Charles Land. Eastside of Jena Isl. 75 m (Romer and Schaudinn 1898, St. 37, St. 30). Norway. Finmark (Loven). Outer part of the Kvaenang fiord 20 — 30 fms. (C. Au- rivillius 1881). 72°io' N. 20°37' E. (1868), Besimennaja bay 4 — 5 fms. (New Zembla-Exp. 1875), New Zembla S. of Cape Goose 3 — 6 fms.. Cape Grebeni 8 — 10 fms. (New Zembla-Exp. 1875). Kara Sea. Jugor Sound. Chabarova 5 — 8 fms (Vega-Exp. 1878). It is not necessary to describe this species in detail as I have before (1893) given a summarj- of its anatomy. To tliis description I will, however, add some observations of the nematocysts, the spirocysts, and the filaments. The size of the nematocysts and spirocysts in the different parts of the body is shown on the following table, n nematocysts, sp spirocysts. Concerning the structure of the filaments the appearance of the intermediate streaks, and probably also that of the ciliated streaks, somewhat recalls the Zoanthids. The ciUated streaks are, as we know, trans- versely sulcated in the Actiniaria, as well as in the Zoanthids. The ridges between the furrows are not sup- ported by mesogloeal oft'-shoots, but by thickenings of the epithelium. In the Zoantliids the furrows and the ridges of the ciUated tract pass into similar furrows and ridges on the intermediate streaks, so that also these latter become transversely sulcated. The ridges of the intermediate streaks are supported by mesogloeal off-shoots, and a narrow band of the ciliated streaks covers the bottom of the furrows of the intermediate The Ingolf-ExpeditioD. V. 9. **^ 122 ACTINIARIA Habitat physa n scapus n Capitiilum ); sp tentacles n sp actinopharynx Godhavn — — about 14 X I ti 19x1 — 36x2,(1 ! 26—36 X 3.5—4 ," Holstensborg . . . — — — — 14—17x1,5 19—34x2 26—34 X 4—5 Greenland (juv.) . — — — — — —34x2,5 29—35 X 4 — — — — 14x1,5 13x1—30x2 (2,5) (26) 31x4 Bel Sound 13 X 1,5 u 13x1.5," 12 — 14 X I u 19 — 29x2 — 2,5 /.I 12 — 17 X 1,5 17x1—36x2,5 26—34 X 4 E. off Iceland . . . — — — — about 14 17x1 — 36x2 — 2,5 29—41x5 Nordrc Stromfiord — — — — 14 22 41 X2,5 24—34 X 4—5 Trenrenberg Baj- . 12—14 12 — 14 12 — 16 X I 28 — 32 12 — 16 — about 28 36—40 Besimennaja Bay. — — — 14x1,5 13 X I — 30 X 2 — 2,5 26 — 31x4 streaks. In the Actiniaria such a structure has not been observed before. Though a more extensive examination of the filaments of Halcampa arctica is desirable, I am, however, able to state that the filaments of this species at least indicate a structure like that of the filaments of the Zoanthids. The furrows and the ridges of the ciliated streaks also here pass into similar furrows and ridges on the intermediate streaks which are also here sup- ported by mesogloeal off-shoots. The nuclei in the lower part of the intermediate streaks look a little differ- ent from those of the ridges. I therefore think that also here bands of the ciliated streaks are prolonged into the furrows of the intermediate streaks. Still a control examination of this feature on better material is desirable. The furrowed part of the intermediate streaks is, however, not as broad in H. arctica as in the Zoantliids. It almost only includes the cun^ed part of the intermediate streaks, while at least half the inter- mediate streaks, adjoining the median streak, are unfolded. The figure 14, PI. 2 shows a longitudinal section of the intermediate streaks {is, is^ and of the ciliated streak {cs). The section has hit the filament a little obliquely. On one side (downwa^rds in the figure) the unfolded intermediate streak {is) has been sectioned, on the other side the sulcated part of the intermediate streak (/sj) is seen. The figure 15, PL 2 also shows a similar section, a little more magnified, almost cutting through the apex of the wings of the filaments. Remarks: The Halcampa-species, until now described, especially H.duodecimcirrata, arctica, chrys- anthellum, arenaria and farinacea, are so very nearly related to each other that it is difficult to find any good species-characters. Probably there are small differences between them, but in order to judge of the constancy of these differences a closer examination is required. The nematocysts and spirocysts are of about the same size as those of the mentioned species. If H addon's statement that only 6 mesenteries are fertile in H. chrysanthellum, is correct, — a renewed examination of this point is desirable — this species is well characterized. As my material of H. arenaria and farinacea is too poor — both species certainly belong to the genus Halcampa as the sphincter is mesogloeal — I will not now discuss these species any further. Con- cerning H. arctica and duodecimccrrata it is possible that we have to do with only one species having its habi- tation proper in the Arctic Sea, where it reaches its largest size, but also distributed at the shores of Nor- way and Sweden and the Eastern sides of Denmark right into the Baltic Sea, simultaneously becoming smal- ler and smaller in size — the numerous specimens from the vicinity of Bomholm and Scania all were very small. For the present it may be the best to retain these forms as different species. To which species Sars's short description alludes, is difficult to decide with certainty. It is possible that his duodecimcirrata is iden- tical with my arctica as a specimen from Ure dredged by Sars and examined by myself had rather richly ACTINIARIA 123 branched pennons. If this specimen is the type, not those from Bergen, I am ahuost inchned to regard arctica and Sars's duodecimcirrata as one and the same species (a closer examination of some other specimens from Lofoten is, however, to be undertaken before deciding it with certainty) If this should be found to be the case, the Halcampa-sj)ecies from South Norway, from Sweden and from the Baltic Sea may be named H. variabilis. Sars has besides, at another time, evidently confounded an Edwardsia proper with a H. duode- cimcirrata. In the museum of Christiania there are several now exsiccated specimens, labelled 0gsfiord, Finmark Sars, and determined probably by himself as Edwardsia duodecimcirrata; in reahty these spec- imens are Edwardsia proper, probably E. andresi, hke H. duodecimcirrata mostly provided with 12 tentacles. Halcampa ? vegae n. sp. PI. I. Fig. 2. Diagnosis: Apertures of the retractile physa? Scapus with a thin, easily deciduous periderm. Nema- tocysts of the scapus, capitulum and tentacles about 13 X 1,5 //. Spirocysts of the capitulum and the ten- tacles unto about 11 /z long. Tentacles probably 12. Perfect mesenteries 12, imperfect 12. lyongitudinal pen- nons of the mesenteries very strong, their ramification almost like that of the pennons of H. arctica. Parietal muscles strong, in transverse-sections not elongated, divided into very fine and numerous branches. Imper- fect mesenteries very finely folded, elongated. Occurrence: Behring Sea 64°52' N. i72°3' W. 18 fms (Vega-Exp. N. 1056) i sp. Exterior aspect: The exterior of the very contracted and partly not well preserved animal (PI. i, fig. 2) recalls that of other Halcampa-sptcies. On account of the strong contraction and involution of the physa I have not been able to examine it more closely. The scapus is provided with a thin, easily deciduous periderm. Round the papillae foreign bodies are fastened. The tentacles were not well preserv^ed, liut are probably 12 in numbers. Anatomical description: The anatomy of this species much recalls that of H.artica. I have indeed not been able to find the sphincter, because of the very bad preservation of the uppermost part of the capitulum and of the tentacles. I do. Fig- 147 Textfigs. 146 — 148. Halcampa? vegae. Transverse section through parts of perfect mesenteries in the repro- ductive region. — Fig. 146: through the pennon. — Fig. 147: through the parietal muscle. — Fig, 148: Transverse section of a mesentery 46 of the second order. Fig ACTINIARIA -I however, think that the species is a Halcampa as it agrees well with other characters of this genus. The pen- nons of the perfect mesenteries are very much branched, as the textfigure 146 shows. The parietal muscles (textfig. 147) are more ramificated than in H. arctica, so are also the muscles of the imperfect mesenteries (textfig. 148). The parietal muscles are not elongated as in H. arctica, but more transversely spread, possibly on account of a different contraction of the muscles. Whether this form is in reality a species different from H. arctica I cannot at present decide Genus Cactosoma Dan. Diagnosis: Halcanipidae with the column divisible into three regions, physa, scapus and capi- tulum. Physa small, often flattened, not ampullaceous, probably without pores. Scapus with a cuticle and " Halcampa-papiHae" . Capitulum with comparatively sparse spirocysts. Sphincter simple, weak, expanding a Uttle into the base of the tentacles. Tentacles short, more than 12. Actinopharynx short, without distinctly differentiated siphonoglyphes. Mesenteries arranged in two or several cycles. Only the mesenteries of the first cycle perfect, fertile and furnished with longitudinal muscle-pennons. Mesenteries of the second (and other) cycles sterile, without pennons and filaments, extended over the whole length of the column. This genus is synonymous with Phelliomorpha, proposed by myself 1902 (compare below under Cac- tosoma abyssorum). As the above diagnosis clearly shows, this genus is nearly allied with Halcampa, and con- sequently it is not a transition form to the Zoanthidae, as declared by Danielssen (1900, p. 85). In addi- tion to the type, Cactosoma abyssorum Dan. (= PhelUacrassa Dan.), I refer to this genus a hitherto undescribed species from the coast of California {Cactosoma arenaria) and Halianthtis chilensis Mc. Murr. Mc. Murrich (1904, p. 224) namely says about this species "The sphincter seems to have been imbedded in the mesogloea, for just below the line of insertion of the outer tentacles there was in the column-wall a narrow band of what seemed to be muscle tissue, enclosed within the mesogloea and separated by narrow bands of it from both the ectoderm and the endoderm". Cactosoma abyssorum Dan. '/^f\ Cactosoma abyssorum, n. sp. Danielssen 1890, p. 82, PI. 6, fig. 5, PI. 23, figs. 5 — 8. ^"^ \ Phellia crassa n. sp. Danielssen 1890, p. 60, PI. 4, fig. 9, PI. 13, figs. 5, 6, PI. 14, figs, i — 5. Isophellia crassa (Dan.) Carlgfen 1900, p. 52. Phelliomorpha crassa (Dan.) Carlgren 1902, p. 44, textfigs. 7 — 11. Diagnosis: Body elongated. Typical nematocysts in the ectoderm of the scapus 10 — 16 x 2 (2,5) fi, in the capitulum 20 — 26 x 2,^11, in the tentacles 14 — 22 X 2 — 2,5 (3,5) fi and in the actinopharynx about 14 — 29 ji in length. In the ectoderm of the latter, nematocysts with discernible basal part to the spiral thread 22 — 33 X 4,5 — 5 n in size. Spirocysts in the ectoderm of the capitulum sparse, in the tentacles very com- mon 24 X almost 2 — 36 X 2,5 (i spirocyst 43 X 4 ju). Tentacles 24 (6 + 6 + 12), the inner about one third longer than the outer. lyongitudinal muscles of the tentacles and radial muscles of the oral disc ectodermal, strong, with palisade-shaped folds. Actinopharynx longitudinally plicated. Two cycles of mesenteries. Lon- gitudinal pennons on the perfect mesenteries strong, in the reproductive region with about 20 — 30 high, rather richly ramificated folds. The outer parts of the mesenteries issue not far from the outer side of the ACTINIARIA 125 pennons. Parietal muscles elongated with close, though not high folds, they are not expanded on the body- wall, or only sHghtly so. Mesogloea in the region of the parietal muscles thick. Muscles in the mesenteries of the second cycle of about the same appearance as the parietal muscles of the first cj-cle. Well developed ciliated streaks. Colour: Scapus bro.wn, with dark, almost black spots. Longitudinal Unes of the capitulum pale red. The rest of the capitulum pale rose-coloured. Tentacles bright salmon-red. Oral disc almost wliite, round the mouth a red annulus, from which 12 fine rose-coloured stripes run towards the margin of the disc (Cac- tosoma abyssorum, Danielssen). Scapus greyish-brown, capitulum almost white, outer tentacles purple, more intensely coloured at the base, inner tentacles rose-coloured. Oral disc purple, with radial violet stripes. The folded oral labiae more intensely purjjle (Phellia crassa, Danielssen). Tentacles light brown (Appel- lof). The whole animal is in alcohol light brown (i sp. from the Michael Sars-Exp.). Dimensions: in extended state: Length of the column 4 cm, breadth i cm in the distal part, 0,5 cm in the proximal part; length of the tentacles 0,2 cm (Danielssen, Cactosoma abyssorum) — length of the column 4 — 5 cm, breadth in the proximal end i — 2 cm or more (T) anie\s5en, Phellia crassa). In preserved state length of the column 1,3 cm, breadth 0,9 cm, inner tentacles 0,2 cm long; outer tentacles 0,1 cm (Phellia crassa) — length of the column 2,2 cm, breadth 0,8 cm (preserved specimen from Greenland). Length 1,8 cm. Largest breadth i cm. Length of the tentacles about 0,5 cm (Spec, from Michael Sars-Exp.). Occurrence: Greenland without distinct locality (Ryder) i sp. Between Spitzbergen and Finmark 74°55' N. i6°i9' E. 400 m (Olga-Exp. St. 53. I sp.), 72°27' N. 20°5i' E. 349 m. Temperature at the bottom 3,5° Sand and clay (Norw. N.-Atl.-Exp. St. 290 — Phellia crassa.) Off Lofoten 68°2i' N. io°4o' E. 836 Temp, at the bottom — 0,7° (Norw. N. Atl.-Exp. St. 164, Cactosoma abyssorum). 62°29' N. 4°i2' E. 518 m. Temp, at the bottom 1° (Michael Sars-Exp. 1902, St. 66), I sp. Exterior aspect: The column is divided in three regions, physa, scapus and capitulum. The most proximal part, the physa, is flattened in the specimens from the Olga- and the North-Atlantic-Expeditions, in the specimens from Greenland rounded and more physa-hke. There is, howe\er, no regular pedal disc as the basilar muscles are absent, but as in many other Actiniaria the most proximal part of the body can be flattened and attached Hke a regular pedal disc, wherefore I supposed in my description of Phelliomorpha crassa (1902) that in fact a pedal disc and also basilar muscles were present. The physa is devoid of a cuticle; in the t\T)e-specimen of Phellia crassa it looks, however, as if it had a cuticle in some parts. The middle part of the column, the scapus, occupies the largest part of this region and is provided with a cuticle and "Hal- campa-papmae" , to which grains of sand are attached. The capitulum is short, without a cuticle and with distinct or indistinct longitudinal furrows corresponding to the insertions of the mesenteries. The tentacles are 24, in three cycles, short, the inner tentacles about one third longer than the outer ones and, according to the state of contraction, cylindrical or conical with a poms in the apex. The oral disc is flattened and small. It is true that Danielssen declares that the oral disc of Cactosoma abyssorum is well developed, but it seems to me that Danielssen has come to this conclusion by regarding an evaginated part of the actino- 126 ACTINIARIA pharj^nx as part of the oral disc. The actinopharynx is short and longitudinally sulcated. The two narrow siphonoglyphes are only little differentiated, symmetrically placed and devoid of aboral prolongations. Anatomical description: For the anatomical examination I have used the type-specimen of Phellia crassa and a piece of the distal part of Cadosoma abyssorum (Danielssen has sectioned the lower part), I have, besides, more closely examined certain parts of the specimens from the other stations. The ectoderm of the physa is rather high and contains nematocysts of the same size as those of the scapus. The ectoderm of the scapus is a little lower and provided with a cuticle and conspicuous "i/a/caw^a-papiUae". It contains typical nematocysts lo— 16 x 2—2,5 ji in size. The ectoderm of the capitulum is devoid of a cuticle and is higher than the ectoderm of the scapus. Its nematocysts are very numerous and nmch larger Fig. 150 l'"ig- 151 Fig. 152 Fig. 149 Textfigs. 149 — 152. Cactosoma abyssorum. Transverse section through the sphincter (fig. 149), through a pennon (fig. 150) through a parietal muscle (fig. 151) and through an imperfect mesen- tery (fig. 152). The sections of the mesenteries are taken from about the middle of the column. Im : longitudinal muscles, ec : ectoderm, en: endoderm. (20 — 26 X 2,5 fi) than those of the scapus. They are sometimes a little curved and tapering in the distal end. Between the nematocysts there are scattered spirocysts of the same size as those of the tentacles, they are, however, much sparser than in the capitulum-ectoderm of Hakampa. The mesogloea of the scapus is much thicker than that of the capitulum and of the physa, but also in these latter regions the mesogloea may be thickened, according to the state of contraction of these parts. The sphincter is mesogloeal, but weak and of about the same appearance as the sphincter of Hakampa. In position it Ukewise agrees with the sphincter of this genus. Also here the sphincter is drawn into the basal region of the tentacles, and the ectodermal muscles of the tentacles and of the oral disc expand over the upper part of the spliincter (compare Hakampa!). I have in another work (1902, p. 45) given two figures of the sphincter of a specimen of Phellia crassa from the Olga-Expedition, here I reproduce a transverse section (textfig. 149) of the sphincter of the type-spec- imen of Cactosoma abyssorum. These figures seemingly correspond well with each another. The strong thick- ening of the mesogloea on figure 8 (1902) is due to a strong contraction of the capitulum, and is of no im- ACTINIARIA J27 portance. Danielssen states that the circular muscles of the column of Cadosoma are mesogloeal, this is, however, wrong; these muscles are, as usual, ectodermal, only the sphincter is mesogloeal, and this part has not been examined by Danielssen — the distal part of the type-specimen not having been sectionized by him. The ectoderm of the tentacles is very high and contains very numerous spirocysts of variable size, from about 24 X almost 2 to 36 x 2,5 pt and sparser nematocysts 14—22 X 2—2,5 (3-5) /^ in size. The ecto- dermal longitudinal muscles of the tentacles are well developed, forming high folds, palisade-shaped and a little ramificated. The mesogloea and the endoderm of the tentacles are thinner than the ectoderm. The radial muscles of the oral disc are rather strong, and appear in transverse-sections as closely packed lamellae. The ectoderm of the actinophar>-nx is rather high and provided with numerous granular gland-cells and rather common, typical nematocysts (about 14 — 20 [i long) ; besides these, there are also nematocysts here with visible basal part to the spiral thread (22 — 33 x 4,5 — 5 \i in size). I have not examined the siphonoglj^phe more closely, but it looks as if it is weakly developed. I have examined the stinging capsules in Phellia crassa as well as in Cadosoma and in the specimen from the Michael Sars-Expedition. They agree well in size; in Plicllia crassa I have not observed any nematocysts with visible basal part to the spiral thread. The mesenteries are arranged in two cycles and are also 24 in number, 6 pairs of perfect and fertile and 6 pairs of imperfect and sterile mesenteries. The former have pennons, the latter not. The folds of the muscle-pennons are ver>' strong and high, especially in the tract of the actinopharynx (fig. 9, 1902) ; in the reproductive region they are from 20 to 30 in number, commonly of equal height and somewhat riclily rami- ficated, particularly in the outer and the inner parts. The outer lamellar part of the mesenteries is attached to the pennon close by its outer edge (fig. 150) . The parietal muscles are strong, in transverse-sections elon- gated, that is, much expanded radially (textfig. 151 from the type-specimen of Cadosoma). The mesogloea is rather strongly thickened in the tract of the parietal muscles ; from the main lamella issue numerous, but not high folds which are more or less ramificated. The folds are of rather equal height, the highest folds stiU being situated in the innermost jDart of the parietal muscles. More strongly contracted parietal muscles appear more flattened. They are only a little or not at all prolonged on the column, so are also the muscles of the imperfect mesenteries, the appearance of which ver^- much recalls the parietal muscles of the perfect mesenteries (textfig. 152 from the type specimen of Cadosoma). In my report (1902, p. 45) I have supposed that Phelliomorpha crassa has weak basilar muscles. A closer examination proves that these muscles are nothing but tlie exterior part of the parietal muscles which, where the physa-region begins, are more strongly curved than the inner parts of these muscles and therefore, in transverse sections through the mesenteries in the region of the physa have been hit trans- versely or obliquely, while the inner part of the parietal muscles are hit more longitudinally. If transverse- sections of the Actiniaria seem to have very weak, not well marked basilar muscles, a control-examination of these muscles ought to be made on surface preparations of the mesenteries, the ectoderm having been pencilled off. On such preparations the arrangement of the muscles is namely more distinct than on single sections. The perfect mesenteries have mesenterial filaments, the imperfect mesenteries none. The ciHated streaks are of typical appearance, their mesogloea contains few cells. Danielssen declares that there are acontia in Phellia crassa, I have not obser\-ed anj' such. Only the perfect mesenteries are fertile. The species is dioecious. 128 ACTINIARIA Remarks: After having examined Danielssen's Cactosoma abyssorum I think that this species is identical with liis Phellia crassa. In the above-named pubhcation (1902) I placed Phelliomorpha [Phellia) crassa among the Paractiidae as I suggested that a regular pedal disc and basilar muscles were developed here. After having stated the incorrectness of this suggestion (compare above) the position of the genus must be among the Halcampidae. Its structure, especially that of the capitular region and of the sphincter, also agrees well with that of Halcampa. It might, however, not be correct to place both genera together in a single genus. The genus Halcampa, although furnished with 2 cycles of mesenteries, has never more than 12 tentacles, while in the genus Cactosoma the development of the tentacles and that of the mesenteries cor- respond in this way that if two cycles of mesenteries appear, the number of tentacles is also more than 12. Fam. Halcampactiidce. Diagnosis: Athenaria without a spliincter or with a diffuse endodermal one. Acontia present. To this family I refer the below described Haliactis and the genus Halcampactis, summarily char- terized by Farquhar (1898), with its two species mirabilis Farq. and duhia Stuck. Farquhar namely states that the aboral end of Halcampactis is rounded and forms a physa and that there are "no sharply defined circular muscles". Stuckey (1908, p. 387), not having had an occasion to see the type, is inclined to take the genus to be a Sagartiid If Farquhar's informations are correct, the family keeps its present name Halcampactiidae ; if, on the other hand, the sphincter afterwards should turn out to be mesogloeal, the genus must be placed among the Andwakiidae, provided that the basilar muscles are absent, which is likely, as Farquhar declares that the type-species has a rounded phj'sa. If Halcampactis has to be removed from the family, it will be necessary to give it a new name, Haliactiidae. It is besides questionable if the genera Ilyactis and Octophellia proposed by Andres, do not belong to this family. If their sphincters are endodermal or no sphincter is present they probably do belong to it, if their sphincters are mesogloeal they are most likely Andwakiids. Halcampactis is no doubt a species provided with brood-rooms. Farquhar namely says about this species "I have found full-grown individuals with numerous young ones grouped around them, evidently as they had attached themselves round the parent, when bom". Genus Haliactis nov. gen. Diagnosis: Halcampactiidae with rounded proximal body-end. Column not divisible into regions, smooth, without papillae and spirocysts. No sphincter. Tentacles rather numerous, short, not swollen in the apex, the inner longer than the outer. Two weak siphonoglyphes and two pairs of directive mesenteries. Only 6 pairs of mesenteries perfect, imperfect mesenteries in several cycles. More than 6 perfect pairs fertile. Distribution of the acontia on the mesenteries? Haliactis arctica n. .sp. PI. I. Fig. 31. Diagnosis: Column elongated. Nematocysts in the column partly 13 — 17 X 1,5 y, partly 17—31 X 3.5—5 n, in the tentacles 20—31 x 2 /^ in the actinopharynx partly 14—17 X 1,5 //, partly 26—36 X ACTINIARIA J2Q 2,5 — 3 [i, partly 19 — 38x3,5 — 5 ^. Spirocysts in the tentacles very numerous 13 X 1,5 n to 29 X 3 /i. L,on- gitudinal muscles of the tentacles and radial muscles of the oral disc rather well developed. Pairs of mesen- teries 6 + 6 + 12; in addition to these pairs a fourth cycle in large specimens. Only the 6 first pairs with pennons, which are strong, furnished with high folds and rather riclily ramificated, especially in the inner and outer parts. Parietal muscles weak, with somewhat low and sparse folds, expanded over all the outer lamellar part of the mesenteries, not sharply outlined from the other longitudinal muscles, not expanded upon the column. Muscles of the mesenteries of the second and third cycles recalling the parietal muscles of the first cycle, but with more numerous folds. Marginal stomata present. Filaments only on the mesen- teries of the first order and on the distal part of the mesenteries of the second one. Ciliated streaks of usual type. Rather numerous acontia with large nematocysts. Reproductive organs on the first pairs and on the distal part of the second pairs. Colour? Dimensions: Largest specimen from Greenland in contracted state: Length 1,6 cm, breadth about 0,9 cm. Another specimen was 1,1 cm long and i cm broad, the inner ten- tacles 0,3, the outer 0,2 cm. Specimen from Siberia: I,engtli 2 cm, breadth i cm. Occurrence: Greenland without distinct locality, 3 sp., West-Greenland Nordre Stromfiord 375 — 380 m. (Nordmann, St. 2). Bear Island (1886), i sp. Spitzbergen. King Charles land 78°5o' N. 29°39' E. 60 — 70 m. Clay (Sw. Spitzbergen- Exp. 189S), I sp. Arctic Ocean of Siberia. 2 miles north of the winter station of the Vega (Vega- Exped.), I sp. Exterior aspect: The column is much more high than it is broad and, according to the state of contraction, now more broad in the distal part, now in the middle. The proximal end is now flattened, now physa-shaped, expanded or involved. In consequence of the strong longitudinal contraction of the body the column shows numerous circular furrows. The column is smooth, without cuticle, papillae and acrorhagi, but with a broad fossa. The distal margin is distinct. The insertions of the mesenteries are clearly visible where the ectoderm is lost ; probably there are longitudinal furrows, corresponding to the insertions of the mesenteries. The tentacles are most likely hexamerously arranged, in four or five cycles. The maximal num- ber is about 96, in the reproduced large specimen (PI. i, fig. 31) I namely counted between 80 und 90 ten- tacles. Probably some tentacles may have been torn off as the preservation of the tentacles was very bad. The tentacles are conical, short, not longitudinally sulcated, and not swollen in the apex, the inner tentacles are about one third longer than the outer ones. The oral disc is probably not wide, it was not well preserved. The actinopharynx is of ordinary length and folded. The two siphonoglyphes are not very distinct and their aboral prolongations short. Anatomical description: The ectoderm of the column, of the tentacles and of the actinophar>-nx is liigh and much thicker than the mesogloea. No cuticle is found. In the different regions of four specimens the nematocysts and the spirocysts show the following size. 'Jhe Ingolf-Expedition. V. g. ■'7 130 ACTINIARIA Habitat column tia nb tentacles M sp actinopharynx na nh «(■ I. Bearlsl 19-25x3.5-5," 15-17x1,5/' 22-26 X almost 2 i( 17x1,5-29x3 fi 29-36 X 5 f^i 29-36x3^ 14-17 X 1,5 u 2. Largest spec. fromOreenland 19-25x3.5-5 ? 20-24 X — 14X1,5-29x2,5-3 29-34 X 5 26-34x2,5 ? 3. Winter-station of the Vega . . 17-23X3.5-5 13-14X1,5 22-26 X — 13 X 1,5-26 X 3 19-26x4-5 26-34x2,5 17x1,5 4. Greenland (Nordmann) 24-31X5? 14-17x1,5 24-31 X — 17x1,5-29x2,5-3 22x3,5-38x5 29-34 X 2,5 ? The a-nematocysts of the column were generally more thin in the distal end, in the specimens i and 3 sometimes a little curved and with indistinctly visible basal part to the spiral thread. In the specimen 2, the maceration preparations of which are a little unreliable in consequence of the bad state of preservation, the basal part of the spiral thread was visible, most of the capsules were destroyed here and only the rib-like basal part left. The b-capsules of the column were of equal breadth. In the a-capsules of the actinopharynx the basal part of the spiral thread was more or less visible, the a-capsules were broader in the basal end, the b- and c-capsules were in all places equally broad. The main part of the capsules in the tolumn and the actinopharynx consists of a-capsules, the b- and c-capsules were very sparse. The nematocysts of the ten- tacles were rather sparse, the spirocysts numerous. The a-capsules of the actinopharynx vary a little in size, I must, however, mention that the size of the capsules in the actinopharynx is unreliable, according to the strong compression of this part ; it is possible that one part of the capsules belongs to the filaments. The size of the nematocysts and the spirocysts besides agrees well in the four specimens. The mesogloea of the column is not thick but very fibrillated, the endoderm is thin. The endo- dermal circular muscles are not strong, in the re- gion of the fossa a little stronger, but form no dif- ferentiated sphincter (four specimens examined in this respect). The longitudinal muscles of the tentacles and the radial muscles of the oral disc are well developed. The pairs of mesenteries are arranged in three cycles 6 -f- 6 + 12 = 24. In addition to these pairs a fourth cycle is probably present in the largest specimen reproduced in fig. 31, PI. i. This spec- imen was namely provided with a greater number Textfigs. 153 — 154. Haliaclis arctica. Fig. 153: Transverse section of a perfect mesentery in the repro- of tentacles than the other specimens (compare ductive tract (spec, from Greenland, .iiyanihus.). Fig. 154: Trans- above) . Only the mesenteries of the first CNxle are verse section of mesenteries of the second and third order and of Fig 154- an acontium (ac) (spec, from Bear Isl.^ perfect and strongly developed, the other mesen- ACTINIARIA 121 teries (fig. 154) have no pennons and their muscles recall the parietal muscles of the first cycle. The longitudinal muscle-pennons of the first 6 pairs are in the reproductive region provided with numerous high folds, ramificated in the outer and inner parts (textfig. 153). The lamellar outer part of the mesenteries is attached to the outer edge of the pennon. The parietal muscles arfe in transverse-sections very elongated, with rather low folds, sparse and only a little branched or not at aU so, on the longitudinal muscle-side passing into the pennon, but not expanded upon the column. The parietal muscles of the specimen from Bear Island and still more of that from the Vega-Expedition are of a more robust appearance than the reproduced section of the specimen from Greenland (in the Vega-specimen the main lamella of the mesogloea is considerably more thick) , prob- ably at least partly because of a different state of contraction. Thej' moreover greatly recall the parietal muscles of Acthelmis intestinalis. The mesenterial filaments are only present on the mesenteries of the first order and on the distal part of the second one. The ciliated streaks are of usual appearance. The acontia observed in sectioned specimens from all habitats are rather numerous, in transverse-sections broad and provided with very numerous nematocysts (textfig. 154 ac). In the specimen from Bear Island there are, as far as I can see, in the perfect mesenteries large marginal stomata near the oral disc. Concerning the reproductive organs I observed ovaria in two more closely examined specimens. They appeared only on the mesenteries of the first order and in the distal part of the second one. Remarks: The specimens dredged off Greenland (without distinct locality) and belonging to the museum of Copenhagen were labelled Ilyanthus{?) arc^j'cMS. Liitk. They are evidently one of the two Ilymithns- species which lyiitken (1875) mentions from Greenland, though never describing them. They were rather badly preserved wliile the other specimens were in better condition. For the anatomical description I have used specimens from all habitats. Fam. Andwakiidae. Diagnosis: Athenaria with elongated, cyhndrical or low, conical column. Proximal body-end forming either an ampullaceous physa or a wide flattened base, recalling a pedal disc. Sometimes with cin- clides? Sphincter mesogloeal, well developed. Acontia present. The preliminary diagnosis of this sub-family, proposed by myself 1893 (p. 38) — I then regarded it as a sub-family — differed considerably from the first diagnosis of the family, given by Danielssen (1890). In fact Danielssen's diagnosis was so extensive that it would include almost all the then described Acti- ninae being devoid of a pedal disc. Danielssen in his diagnosis neither mentions the presence of acontia nor the occurrence of a mesogloeal sphincter, two characters of great importance to the limitation of the family. Perhaps Danielssen comes nearer to the mark when speaking of the systematic placing of the family. According to the Norwegian author the family namely forms a transition stage between the Edwardsids and the Sagartids (the Phellidae). Among the Athenaria the family is, according to me, most nearly related to the family Halcampidae with which it has several characters in common, such as the exterior habitus of the body, the occurrence of ".H^a/cawf^a-papiUae" and few perfect mesenteries, the absence of basilar muscles and the presence of a mesogloeal sphincter. With the PheUidae, on the other hand, it agrees for instance in this that acontia occur. Probably we may regard such forms as the Andwakiidae as transition IT* ACTINIARIA 132 stages to at least certain species described as Phellia, very likely not a homogeneal genus. Besides it does not seem improbable that the Sagartids including at present all Actiniaria with basilar muscles and sphincter are of polyphyletic origin, a suggestion which, however, requires closer examination in order to be confirmed 1. To tliis family I think that also the genus Octineon Mosel, belongs. In fact this Actinia is not as re- markable as Fowler supposes and as I can confirm from my own examination of type-specimens. The basal disc and the column, both incrusted with grains of sand, have no doubt an ectoderm, though the strong incrustation makes it difficult to ascertain its true nature. It is besides difficult to get a good figure of the ectoderm because the cuticle of the scapus, viz. the incrusted part of the column, is very strongly folded. On the sections it seems as if the scapus is provided with "i/afc«m/)fl-papillae". On the other hand, Fowler supposes that a secretion of mesogloea by wandering cells from the endoderm takes place for the adhesion of the sand — he declares, however, that he has not observed any such cells. The capitulum is short, without a cuticle and probably without spirocysts. The sphincter is very elongated, mesogloeal, with, especially in certain places, scattered meshes. The tentacles are 12, of which 6 are primary-endocoel and 6 exocoel tentacles. They are capable of invaginating like the tentacles of Halcampoides. Their ectodermal muscles are ^•ery weak. Like Fowler I have not observed any distinct siphonoglyphes. The number of mesenteries is in the proximal part very great, this is closely correlated with the large diameter of the basal disc. In one specimen I counted 157 mesenteries in this part, thus a much greater number than stated by Fowler. Two cycles of mesenteries in the examined specimen reach the capitular region. Of the mesenteries of the first cycle only the 8 "Edwardsia-m&s&nt&ri&s" are perfect, as far as I can see. Fowler declares that some of the weaker mesenteries are attached to the actinopharynx, and also the four couples which, together with the 8 "ft^- t£iflri?sia-mesenteries", form the 6 pairs of mesenteries of the first order. Still on Fowler's reproduction (fig. 12, PI. 30, 1888), only the six first pairs are connected with the actinopharynx. According to Fowler the section liits the actinophar>'nx. It is, however, questionable whether it really is so, I am more inclined to think that the section is more distal — a mistake which may easily have occurred to Fowler as he de- clares that "in the histological conditions no differences are apparent between the stomadaeum and the oral disc", and the strong contraction of this part has rendered it more difficult to examine the insertions of the mesenteries. In fact the actinopharynx is easily distinguished from the oral disc, because the former is devoid of ectodermal muscles, while the latter has such. In the best preserved specimen, sectioned by myself, only the 8 " Edwardsia-xa&SQnt&nQs" certainly were perfect, and besides, no mesenteries but these reach the inner part of the oral disc. As to two other sectionized specimens I cannot determine the number of the perfect mesenteries, on account of the bad preservation and the animals being torn asunder in the region of tlie actinopharynx. Nevertheless it is not impossible that, in certain cases, some more mesenteries may be attached to the actinopharynx, it is namely to be observed that no reproductive organs were developed in the above-named specimen. As, however, this was one of the largest specimens and furnished with very nume- rous mesenteries I think that there is little reason to suppose that possibility. The 8 Edwardsia-m.^e.ntenes have very strong, in transverse-section perfectly circumscript, muscle-pennons, filaments and reproductive organs, the ventral mesenteries of the dorso-lateral pairs (the 5th couple), according to Fowler, has only ' compare p. 19. ACTINIARIA 133 weak pennons and is devoid of filaments and reproductive organs. The 6th couple, the ventral mesenteries of the ventro-lateral pair, is only a little stronger than the subsequent mesenteries, which are all sterile and devoid of pennons and filaments. No distinct parietal muscles are present. The parieto-basilar muscles — one half of the parietal muscles — hardly show any folds, not even on the perfect mesenteries. Basilar muscles are absent. There are ciliated streaks. I cannot, however, describe their appearance as they have been hit longitudinally. Typical acontia with close, large nematocysts are present, but I cannot decide which mesen- teries have acontia. They have not been observed by Fowler. I tliink that the genus Octineon may be cha- racterized as follows: Andwakiidae with very wide basal disc and low conical body, much smaller in the distal part than in the proximal one. Column divisible into two regions, a proximal part, scapus, the lower part of which forms the flattened basal disc, and a short distal part, capitulum. The ectoderm of the scapus with a cuticle and "^flfcaw/>fl-papillae" (to which grains of sand are attached). Capitulum without a cuticle and spiro- cysts. Sphincter mesogloeal, very elongated. Tentacles 12. No distinct siphonoglyphes. The 8 " Edwardsia- mesenteries" (or some more mesenteries?) perfect, fertile, with filaments and strong, perfectly circumscript, pinnate muscle-pennons. The 5th couple with weak pennons, but without filaments and reproductive organs. The 6th couple and the subsequent mesenteries like the 5th couple, but weaker and without pennons. Nu- merous mesenteries in the proximal part of the body. Parietal muscles not distinctly differentiated, weak parieto-basilar muscles. Ciliated streaks and acontia present. Octineon is particularly interesting because of the transformation of its proximal body-end. Instead of forming a physa this part is flattened like a regular pedal disc (compare Milne-edwardsia carnea (p. 16,63) which, under certain circumstances, can flatten its proximal part) and, in comparison with the distal part, considerably increased in size and provided with " Halcampa-papUlsie" , to which grains of sand are attached. Thus the proximal body-end serves as a good anchor to the animal which is incapable of attaching in the usual way. T S fc. ^ -f Genus Andwakia Dan. Diagnosis: Elongated Andwakiidae with the column divisible into physa, scapus and capitulum, the first of wliich being onlyaHttle differentiated from the second. Scapus with " //a/ca w/)fl-papillae". Capi- tulum without spirocysts. Sphincter elongated, strongly mesogloeal in the distal part reaching the basal region of the tentacles as in Halcampa. Tentacles more than 12. Two rather feebly developed siphonoglyphes. 6 pairs of perfect and fertile mesenteries with strong muscle-pennons. One or several cycles of sterile(?) im- perfect mesenteries with weak muscles without pennons. Acontia present, Ijut few in number. Column with cinclides(?). The above diagnosis of the genus only shghtly agrees with that given by Danielssen 1890. Also my description of the species differs considerably from that of this author. As it would be too elaborate to point out all the differences between my conception of the organisation of Andwakia mirabilis and that of Danielssen, I here give a mainly new description of the species which nowise deserv'es the name of mira- bilis. On the contrary its organisation scarcely de\'iates from that of a typical Actinia, as far as I can see. ACTINIARIA 134 Andwakia mirabilis Dan. Andwakia mirabilis n. sp. Danielssen, 1890, p. 86, PI. 4, figs. 10 — 11, PI. 11. Appellof 1893, p. 12. Diagnosis: Physa ampullaceous, probably without papillae, as for the rest like the scapus. Scapus with a cuticle and very distinct "i/«/ca»;i/'«-papillae". Capitulum in contracted state with high ridges be- tween the insertions of the mesenteries. Sphincter elongated, about twice as long as the capitulum, not stra- tified, not forming an offset. Tentacles about 24 in three cycles. Nematocysts in the scapus 13 — 17 X 2 //, in the capitulum 17 — 18 X 2,5 ;i, in the tentacles 19 — 24 u and in the actinopharynx 19 — 22 X 2 (i. Spiro- cysts of the tentacles 17 X 2 — 29 X 3,5 /i. 12 pairs of mesenteries. Muscle-pennons in transverse-sections through the upper part of the reproductive region with about 20 high folds which are richly ramificated and slightly recalling a circumscribed sphincter. Parietal muscles comparatively weak with few folds, not expanded upon the column. Muscles of the mesenteries of the second order recalling the parietal muscles of the mesenteries of the first cycle. Colour according to Danielssen: The scapus brownish-black, dotted with partly white, partly green and reddish points. The capitulum faintly salmon-red, occasionally purely white with a fine rose- coloured tinge. The oral disc cinnabar-red with fine, darker lines. The tentacles of the same colour but some- what darker at the base, lighter at the apex. Dimensions in extended state: Length of the body 6 — 7 cm, breadth in the distal end 1,5 cm, in the proximal end 0,4 — 0,5 cm. Length of the capitulum 0,8 cm, breadth of the oral disc 1,2 — 1,4 cm (Danielssen). — In preserved state to about 2,5 cm long. Occurrence: Norway. Sognefiord. Huson 100 — 150 fnis. Sand (Norw. North- Atl. -Exp., Grieg, 1889), Hjelte fiord (Appellof). Exterior aspect: The proximal part of the body, the physa, is ampullaceous or flattened and, as it seems, but little differentiated from the scapus. As on the scapus the ectoderm is here furnished with a cuticle? (compare below) to which detritus-particles are fastened; it seems, however, that this cuticle is more easily thrown off than that of the scapus. Probably there are no " Halcampa-papiUae" here. The scajjus is elongated, narrow in the proximal part, more broad in the distal part, and set with numerous " Hakanipa- papillae" to which grains of sand are attached. The capitulum is short, without a cuticle and in contracted state provided with high ridges and deep furrows, the latter corresponding to the insertions of the mesen- teries. The body is in extended state cornucopia-shaped (Danielssen), in contracted state cylindrical. The tentacles are 24, arranged in three cycles, short, conical or cylindrical, according to the state of contraction. The inner tentacles are a little thicker than the outer ones. The oral disc is not broad, the actinopharynx rather short, in preserved state with irregular longitudinal and transversal folds. Two, not very distinct siphonoglyphes are present. Anatomical description: The ectoderm of the physa is rather high and contains somewhat numerous nematocysts of the same appearance and size as in the ectoderm of the capitulum. At the outside it is surrounded by a thin covering, imbued with detritus-particles, this is possibly a cuticle but more prob- ably a mucus-membrane secerned by the mucus-cells. The mesogloea of the physa is much thinner than its ectoderm. The ectoderm of the scapus is thinner than that of the physa and contains nematocysts, 13 — ACTINIARIA 135 17 u long. The periderm is thicker than the covering of the physa and imbued with detritus, especially on the numerous papillae which seem to be .of the same nature as the " Halcampa-papiWae" , though they are here supported by strong prominences of the mesogloea. The smooth ectoderm of the capitulum is high and provided with rather numerous nematocysts, 17—18 x 2,5 u in size, sometimes a little curved, hut without Fig- 155 Tcxtfigs. 155 — 15S. Andivakia mirabilis. F'g- 155: Longitudinal section of the upper part of the column and of the basis of a tentacle showing the me- sogloeal sphincter (; tentacle, ca: capitulum, t; cuticle. Fig. 1 50: Transverse section of a pennon in the lower part of the actinopharynx. Fig. 157: Transverse section of a perfect mesenterj' in the reproductive tract. Fig. 158 : Transverse section of a mesentery of the second order. spirocysts. Its mesogloea is thick, especially at the ridges. The endoderm of the column is somewhat thick, in the physa thinner than the ectoderm. The endodermal circular muscles are rather well developed and form short, paHsade-shaped folds. The sphincter (textfig. 155) is mesogloeal and strong, elongated, about twice as long as the capitulum, not forming an offset, not stratified. The most distal part of the sphincter much recalls the sphincter of Halcampa. It is namely here divided in somewhat fine meshes and is so much elongated that the longitudinal muscles of the tentacles cover the uppermost part of the sphincter. It is besides, as in Halcampa, rather close to the ectoderm. In the other, larger part of the sphincter, where the 136 ACTINIARIA mesogloea commonly is more thick, the meshes are more scattered, and larger and smaller meshes are in- termingled. The ectoderm of the tentacles is high and contains rather numerous nematocysts, 19 — 24 /j. long, and very numerous spirocysts of variable size, from 17 x 2 // to 29 x 3,5 /i. The longitudinal muscles are ectodermal and well developed in the proximal part, here forming palisade-shaped folds, in the distal part, however, weaker. At the base the longitudinal muscles are a little stronger on the inner side than on the outer one. The endoderm is liigh and extended in numerous off-shoots. The ectoderm of the oral disc contains nematocysts similar to those of the tentacles, their number is, however, considerably smaller. The radial muscles are strong and almost exclusively ectodermal, still there are sparse meshes enclosed in the mesogloea. The folds are numerous and higher than the un- folded part of the mesogloea. The ectoderm and the mesogloea are much thinner at the insertions of the mesenteries than in the intermediate parts. The actinopharynx is folded. The ectoderm contains verj* numerous typical nematocysts, 19 — 22 X 2 [I in size, besides these also sparse nematocysts with visible basal part to the spiral thread. The latter are broader in the basal than in the distal end and 22 — 26 X 3,5 it in size. The gland-cells are numerous; lon- gitudinal muscles absent. The mesogloea is thicker than the ectoderm at the ridges, weaker in the furrows. The siphonoglyphes are narrow, their ectoderm contains less numerous nematocysts and gland-cells than the other part of the actinopharynx. The pairs of mesenteries are 12 of which two pairs of directives. 6 pairs are perfect and 6 imperfect. The pairs of the first cycle are provided with large, longitudinal muscle-pennons which are, however, rather short and mostly developed in the distal part. The larger part of these mesenteries is devoid of pennons and the proximal part of the mesenteries therefore looks like thin lamellae. On the top of the lower part of the actinopharynx the pennon is the most developed on the outside, the folds are high and rather richly rami- ficated here (textfig. 156). In the reproductive region the pennon is, however, almost as much developed on the inside as on the outside. As the outer lamellar part of the mesenteries issues from the middle part of the pennon, wliich is thickened in the region of the actinopharynx as well as in the reproductive tract, the pennon looks rather circumscribed in transverse-sections through the reproductive region (textfig. 157). The folds amount to about 20 in number. The parietal muscles are not strong, the folds are few, low and not transversely expanded, but radially elongated (textfig. 157). They are not expanded upon the column. The muscles of the mesenteries of the second order (textfig. 158) have no pennons and are in transverse- sections of about the same appearance as the parietal muscles of the first cycle. The filaments are well deve- loped on the mesenteries of the first cycle. Whether such filaments appear also on the mesenteries of the second cycle I cannot with certainty decide as my material was not in every respect well preserved, it seems, however, in certain cases as if also these mesenteries might be provided with very weak filaments. The cili- ated streaks are of typical appearance, their mesogloea contains few cells. Acontia are present, but I cannot decide where they are attached. I have observed them in transverse-sections, they are typical and provided with large nematocysts. The reproductive organs are developed in the proximal part of the pennons of the mesenteries of the first cycle. In two examined specimens they were ovaria. I have not found any reproductive ACTINIARIA 137 organs on the mesenteries of the second cycle, and look upon the occurrence of such organs on the mesente- ries as very improbable. There are small oral stomata. Whether the large marginal stomata, observed by myself in certain mesenteries, are normal formations or not, I cannot with certainty decide. It is possible that they are artificial and due to ruptures as the specimens were strongly contracted. Remarks: The specimens examined by myself were dredged by Grieg in their primary habitat and no doubt identical with the species of Danielssen. Thenaria s. Basilaria. Fam. Actiniidae. Diagnosis: Basilaria with pedal disc commonly well-developed. Column smooth or provided with verrucae (sucking warts) but never with ampullaceous offshoots. Pseudoacrorhagi and acrorhagi (bourses marginales) present or absent. Sphincter absent or weak, endodermal-diffuse or diffuse-circumscribed, rarely aggregated. Tentacles cylindrical or conical, without a sphincter at their base. Mesenteries arranged in several cycles, of which generally more than one is perfect. I,ongitudinal muscles very rarely strongly circumscribed, mostly diffuse. Acontia absent. Genus Actinia Brown. Diagnosis: Body rather low. Column smooth without verrucae, its upper part capable of involu- tion. Fossa distinct, deep. Acrorhagi, well-developed offshoots from the inner part of the fossa-wall in variable number (rarely absent.). Sphincter broad, diffuse endodermal (or meso-endodermal in .4. bermu- densis teste Mc. Murrich). Tentacles short conical. Siphonoglyphes well-developed. Mesenteries numerous, mostly perfect. Reproductive organs in the mesenteries of the first and the following orders, except as a rule in the directive and the youngest mesenteries. Whether A. bermudensis really is provided with a meso-endodermal sphincter needs confirmation. Possibly the section has hit the sphincter in the vicinity of the mesenteries, where all sphincters show a tendency to be more or less mesogloeal. Actinia equina L. Priapus equinus n. sp. Ivinne, 1758 p. 656. Actinia equina I.. I^inne 1766—68, p. 1088. Miiller 1776, p. 230. Andres 1883, p. 393. Jourdan 1880, p. 65, PI. 4, figs. 19—27, PI. 5, figs. 28 — 40. Brunchorst 1890, p. 30. Simon 1892, p. 42. Appellof 1900, p. 4, 1905, p. 59. Grieg, 1887, p. 12, 1898, p. 6. Pax, 1907, p. 53 (p. p.), 1908, p. 467, 1920, textfig. I, 2. Actinia ntesembryanthemum n. sp. Ellis & Solander 1786, p. 4. — — EU. & Sol. Rapp 1829, p. 52. PI. 2, fig. I. Sars 1851, p. 144, 1853, p. 12, 1857, p. 32. Danielssen & Koren 1856, p. 87. Danielssen 1861, p. 45, Mobius 1873, p. 149. Schulze 1875, p. 139. Priapus rubey n. sp. Forskal 1775, p. loi, p. 27, fig. a. 18 The Ingolf-Expeditioo. V. 9. Q ACTINIARIA 138 AcUnia rubra, Forsk., Sars 1835, p. 3, 1853, p. 12. PActinia cari delle Chiaje, Arndt 1912, p. 123. A more complete list of synonyms and literature is given by Andres 1883 and Pax 1908, p. 467. 1 think however that A. rufa of M tiller is not this species but rather a young Metridium dianthus. A. cari is probably a distinct species. Diagnosis: Nematocysts of the column 14 — 19 x 1,5 fi, those of the acrorhagi 41 — 58 (65) X 2,5 — 4 (I, those of the tentacles 19 — 24 x 1,5 « and those of the actinopharynx 18 — 29 X 1,5 (2) 11. Spirocysts of the tentacles 14 X i — 29 X 2 11. Acrorhagi spherical with an aperture, in variable number (commonly 24 teste Andres). Sphincter with low folds especially in its proximal and distal parts, the folds however rather much ramiiicated. Outer parts of the oral disc with tentacles in number to about 192. Inner tentacles a Uttle longer than the outer ones. Pairs of mesenteries to about 96. lyongitudinal muscles in the outer parts of the mesenteries very weak, in the inner forming rather weak diffuse pennons. Parieto-basilar muscles distinctly definite, broad, expanding over almost the whole length of the column. Basilar muscles strong. Development of the embryos in the coelenteric cavity. Colour very variable. Pax (1907, 1920) distinguished two main formsi) forma rubra: Red or scarlet- red. Acrorhagi blue. Sometimes blue annulus at the base of the column (the Bergen-specimens lack this an- nulus teste Appellof), 2) forma viridis: Column olive grey to grass-green, acrorhagi bluish-green, annulus blue. Sars states that liver-coloured specimens (forma hepatica Gosse?) are common in Ogsfiord and at Ham- merfest. Gosse and Andres described several varieties of colour in this species. Dimensions: in expanded state: breadth to about 7 cm, height to 5 cm, length of the tentacles to 1,5 cm (Andres). Occurrence. Norway: The West coast at least from Stavanger (teste Brinkman) to Hammer- fest. Bergen (teste Sars, Appellof), S0lsvig (teste Schulze and Sars), Vaagsfiord, Ulvesund, outer Nordfiord (teste Grieg), Molde (teste Arndt, A.cari'>). Nordland — Finmark toVadso (teste Danielssen), Ogsfiord, Ham- merfest (teste Sars). Kola peninsula. Pala Guba (teste Pax). Shetland Isl. Balta sound (Hammarsten, i sp.) (teste Norman). PDenmark. Great Belt, Romso (teste Mobius, probably not this species). Further Distribution: North Sea, coast of Germany (Helgoland and other localities). Great Britain and Ireland. W. coast of Europe, W. coast of Africa to Cape Verd Isl., Madeira, Canary Isl., Medi- terranean, Black Sea, Sea of Asov. — on exposed rocks from half-tide to low-water mark (Gosse). The exterior aspect of this species has been described by several authors, hkewise the anatomy especially by Jordan (1880), Simon (1892) and Pax (1920). I will here only add some notes. I have exa- mined two species, one from the Shetland Islands (height 0,7 cm, breadth 1,5 cm) another from Naples (height 2 cm, breadth 5 cm), as regards the stinging capsules. Though the specimens were very different in size the stinging capsules were of about the same size in them both. The nematocysts of the column were very sparse, 14 — 19 X 1,5 !x resp. 14—16 X 1,5 /^, those of the tentacles not numerous 19—22 X i,5/i resp. 19 — 24 X ACTINIARIA joQ 1,5 ft, those of the actinopharynx were numerous 18—24 X 1,5 fi resp. 22 — 29 X 1,5 (2) fi. The nematocysts of the acrorhagi were of about equal length in both specimens 41 — 55 (i nematocyst 65) /i resp. 43 — 58 /i, in breadth however different 2,5 jj. resp. 3 — 4 fx. There were moreover in the first specimen broader nemato- cysts, to about 4 n, but they were more irregular and probably nematocysts in development. Also sparse spirocysts are present in the ectoderm of the acrorhagi. The acrorhagi are perforated by an aperture as already shown by Dal yell. In sectionized arorhagum of a specimen from the North Sea the aperture was aborally situated. At the aperture in the mesogloea there was an annular wall, probably formed by the endoderm. The wall, wliich probably forms a movable stopping, is turned outwards. Whether other apertures, cinchdes, are present in the upper part of the column I cannot decide (compare Andres 1883, Simon 1892 and Pax 1908). A priori it may very well be so as the cinchdes are not correlated with the acontia. Several Actiniaria namely have acontia but no cinclides, and others, as Eloactis and Harenactis, have cinclides but no acontia. Fam. Boloceridae. Diagnosis: Basilaria with a well-developed basal disc. Column without sucking warts, acrorhagi and pseudoacrorhagi. Sphincter from rather well-developed to strong, endodermal diffuse or circumscribed. Tentacles at the base constricted and furnished with an endodermal sphincter, by the contraction of which the tentacles are thrown off. This family is proposed by Mc. Murricli (1893) for the germs Bolocera. At the same time he suggested that the Liponema of R. Hertwig was synonymous with this genus. Haddon (1898, p. 429) was of the same opinion and this was further confirmed by myself (1899, p. 40), as I found some tentacles in the type-spec- imen. Haddon moreover thinks that Polystomidium is very closely allied to Bolocera, and I myself gave as my opinion 1899 that both genera are identical and that the presence of acrorhagi and the occurrence of openings in the actinopharynx are the only characters through which Polystomidium is distinguished from Bolocera. The presence of acrorhagi was doubted by Haddon (1898), and their absence was stated by mj^self 1899, when I had examined the type-specimen. To my mind the openings are of little importance, because they probably are artificial products. As for me, I think that Bolocera and Polystomidium are synonymous. Later (1899) I proposed for Bolocera mc. murrichi Kwietn. a new genus Boloceroides which was re- moved to the family Gonactiniidae, though I pointed out (1900) that the genus does not at all agree with the typical Gonactiniidae. With the placing of Boloceroides among the Gonactiniidae Pax (1914, p. 608 and Poche (1914, p. 97) agree, and Stephenson (1918a, p. 20) declares that it may be doubted, if the genus belongs to the Boloceridae, though he thinks that its "position needs reconsideration." In a paper which I am going to publish I will show that the family Ahciidae is heterogeneous — an opinion which I expressed already 1898 and 1900 — I put Boloceroides together with Bunodeopsis, Alicia and Thaumactis in the family Aliciidae, while Phymactis, Rivetia (= PPhymactis), Cystiactis, Phlyctenactis (= Cystiactis) and Eucladactis (probably = Phymactis) are removed to a new family Cystiactiidae and Phyllodiscus to the Lebruniidae (Dendromehdae) . A new Bolocerid genus, Boloceropsis, was estabUshed 1904 by Mc. Murrich. Concerning this genus 1 8* 140 ACTINIARIA ^ I have before given utterance to my doubt of its place among the Boloceridae. True enough, the tentacles are constricted at the base and the mesogloea of the tentacles thicker than that of the oral disc, whereby a narrowing is formed at the base of the tentacles, but there is no tentacular sphincter. On account of this it is very improbable that the tentacles are able to loosen themselves. For the present I hold it suitable to place the genus among the Actiniidae. Pax (1914, p. 610) and Poche (1914) share my opinion, while Stephenson (1918, a, b) comes to the same conclusion as Mc. Murrich. Stephenson (1918a, p. 20) supposes, that also Polyopis is a Bolocerid. In consequence of the reasons I have before given (p. 81, 82) I must place this genus to the Athenaria. At last Stephenson (1918 b, p. 112) proposes a new genus, Leipsiceras, for such Bolocera forms which have "an extremely long and pecuHar circumscribed sphincter." In this I fully agree with him. I have found a new species of this genus from Gote Islands having a still stronger sphincter than that of the type, L. pollens. To tliis family thus only Bolocera and Leipsiceras to my mind belong. From the species, enumerated by Stephensop (1918 b, p. 112), the following must be removed. i) Bolocera brevicornis Mc. Murr. which, according to Mc. Murrich (1904, p. 255), is a Boloce- roides. 2) Bolocera africana Pax which is a Sagartiid (Carlgren, 1911, p. 21). 3) Bolocera norwegica Pax. Nothing in the imperfect description indicates that the species is a Bolocera (Carlgren 1911, p. 21). Genus Bolocera. Diagnosis: Column smooth, sometimes (always?) with scattered irregular gland-spots, not or only a little capable of involution, with a distinct fossa. Sphincter endodermal diffuse. Tentacles in contracted state longitudinally sulcated, generally very numerous, short or of considerable length, hexamerously ar- ranged. Ivongitudinal muscles of the tentacles and radial muscles of the oral disc ectodermal. Two well- developed siphonoglyphes with distinct gonidial tubercles and aboral prolongations. Muscle pennons of the mesenteries rather well-developed, parieto-basilar muscles rather weak, basilar muscles distinct. More than 6 pairs of perfect mesenteries. Distribution of the reproductive organs on the mesenteries variable. Bolocera tuediae (Johnst.) Gosse. Actinia tuediae n. sp., Johnston 1832, p. 163, fig. 52. Anthea — (Johnst.), Johnston 1847, p. 242, fig. 53. Sars 1846, p. 29. Diiben & Koren 1847, P- 267. Danielssen & Koren 1856, p. 87. ), Milne-Edwards 1857 — 60, p. 235. ), Gosse i860, p. 186, PI. 5, fig. I. Verrill 1873, p. 5, 1883, p. 59. Schulze 1875, p. 140. Andres 1883, p. 421. Levinsen 1893, p. 396. Appellof 1894 — 95, p. 11, 1905, p. 67, 71. Grieg 1897, p. 6, 7, 9, ir, 13, 1913, p. 144. Parker 1900, p. 753. Carlgren in Nordgaard 1905, p. 159. Walton 1908, p. 215. Pax 1909, p. 342, 343. Stephenson, 1918 b, PI. 14, fig. 2, PI. 20, figs, i, 3 — 6. Anetnonia — ( Bolocera — ( ACTINIARIA 141 Bolocera longicornis n. sp., Carlgren 1891, p. 241, 1893, p. 50, PI. i, fig. 18, PI. 6, figs. 3 — 6, PI. 7. Walton 1908, p. 216. Stephenson 1918 b, PI. 20, fig. 7. Diagnosis: Body cylindrical, in expanded state considerably longer than it is broad. Spliincter diffuse, of about the same appearance as in Bolocera muUicornis. Circular muscles in the endoderm of the column rather strong. Tentacles conical, in expanded state very long (in regenerating specimens short?), but strongly contractile, with deep longitudinal furrows, covering about half the oral disc, numerous, ar- ranged in 5 or 6 cycles, the outer tentacles about half as long as the inner ones. Longitudinal muscles of the tentacles and radial muscles of the oral disc well-developed with close, rather high folds. Aboral prolonga- tions of the siphonoglyphes long. All or almost all mesenteries perfect in 4 or 5 cycles. Oral and marginal stomata present. Longitudinal and basilar muscles about as in B. muUicornis, parieto-basUar muscles half as long as the column, weak but distinct. Reproductive organs on most mesenteries except the directives and some others of the first (second) cycle ? Nematocysts in the ectoderm of the column variable, partly 14 — 19 X 1,5 «, partly 26 — 48 X about 2.5 — 3,5 //, those in the apex of the tentacles in smaller specimens 60 — 82 X 2,5 — 3 fjL, in larger 70 — 127 X 3 — 3,5 /i, those in the proximal part of the tentacles in smaller spec- imens 36 — 60 X 2,5 — 3 n, in larger 53 — 72 (86) X 2,5 — 3 n, those of the actinopharynx (38) 43 — 62 X 3— 4 fi. Spirocysts in the ectoderm of the tentacles 22 X i — 2 ji to about yy X 4 — 5 //. Colour: Column varying from pale flesh-coloured and pink to dark red. Tentacles and oral disc generally correspond in colour with the column but are of a deeper tint, on the inside often reddish brown, in which case also the oral disc is of the same colour but of a fainter shade. Gonidial tubercles and mesen- teries sometimes carmine. Dimensions: Length in expanded state unto 20 cm, in preserved state about half as long. In con- tracted state the diameter of the disc is almost like the length of the column. Inner tentacles about the length of the column in expanded state. Occurrence: The Sound, Oretvisten about 40 m ("Sven Nilsson") i sp. Sweden. Gullmarfiord 40 — 80 fms. (Carlgren and others), Vaderoame (Goes). Skagerrak, 370 fms, 320 — 380 fms (Gunhild-Exp., St. 10, 5, 6). 120 fms (Petersen 1887), 244—338 m (Thor-Exp. 1904, St. 312), (Thor-Exp. 1906, St. 11), (Thor-Exp. 1911, St. 6), i5'/o miles NV2W. of Skagen's Ughtship 140 m (Thor-Exp. 1904), 16V2 miles SW. to W. of Skagen's Ughtship 106 fms (Petersen), NW. to W. of Hanstholm (Pommerania-Exp. , teste Schulze). Norway, Christianiafiord Konglungen about 10 m (Christiania mus.), Drobak (Carl- gren, Christiania mus.), Hardangerfiord, Jonanes, Saetveitnes, Thorsnes, Ljonestangen, Straumastein 100 — 400 m (teste Grieg), Herlofiord 150 fms (teste Appellof), Korsnes 337 fms (teste Schulze), Vaagsfiord 120 fms (teste Grieg), Sulenfiord 430 m. Temp, at 400 m 7°22 (M. Sars exp. 1902, St. 32), Drontheimfiord (Biol, stat.), Malangen fiord 380 m. Bottom temp. 4°i, Stonesbottn 40 — 80 m (Nordgaard), Lyngo (Kier). ACTINIARIA North Atlantic: 6o°57' N. 3°42' E. 350 m. Bottom temp. 6°i6 (M. Sars-Exp. 1902 St. 47), 6i°3' N. 2°i3' E., 130 m. Temp, at 125 m 6°7S (M. Sars- Exp. 1902, St. 49), 6i°4' N. 3°ii' E. 400 m Bottom temp. 6°34 (M. Sars-Exp. 1902, St. 51), 59°35' N. 7°8' W. 585 fms (Ingegerd & Gla- dan-Exp.), s'/siniles S.S.E.of Bispen.Faroe Isl.,5ofms(Mortensen). S. of Iceland 49=38' N. ii°35' W. 923 m (M. Sars-Exp. 1910, St. 4). West Greenland: Bredefiord 490 m (Rink-Exp. 1912, St. 49). Davis Strait 64°54' N. 55°io' W. 393 fms Bottom temp. 3°8 (Ingolf- Exp. St. 27). Davis Strait 65°i4' N. 55°42' W. 420 fms Bottom temp. 3°5 (Ingolf- Exp., St. 28). Further distribution: North Sea. Coast of Great Britain and Ireland (teste Gosse, Stephenson and others), Shetland Isl. (teste Norman), Atlantic coast of North-America, Nova Scotia 50 — 100 fms. Gulf of Maine 50 — 150 fms, Casco bay 40 — 90 fms, Massachusetts bay 40 — 52 fms. Cape Cod 37 — 90 fms, George's bank 306 fms, Martha's Vineyard 160 — 640 fms. Southern New England, Cape Fear 464 fms (teste Verrill). In mj' paper (1893) I have left the question open, if Bolocera tuediae and B. longicornis are ident- ical or not. It seems to me from the above list of synonyms that we have to do with a single species, though the figures reproduced by Johnston and Gosse of B. tuediae, apparently the species with very strongly contracted tentacles, do not agree with the common appearance of B. longicornis in contracted state (com- pare Carlgren 1893). The tentacles of B. longicornis namely are capable of varying extraordinarily in length, owing to their strong longitudinal muscles. In recently dredged, sound specimens the extended tentacles are very long — the tentacles of the specimens living in the aqvarium of the biological station of Drontheim are of the same appearance — while half dead specimens have very short tentacles but often strongly swollen at the base (about as the figure reproduced by Gosse). Thus I think that the difference in length of the ten- tacles in B. tuediae and longicornis is due to a different state of contraction. Another difference in the exterior of both species consists in the presence of columnar warts in B. tue- diae, which are not observed in B. longicornis. Gosse not having seen the species alive namely says (i860, p. 186) that B. tuediae "is studded, somewhat sparsely, with minute rounded warts, which are scarcely apparent, when the animal is extended, but, on contraction, "resemble the heads of small pins in a pin- cusliion "(W. P. Cocks)." The figure PI. 5 in the work of Gosse representing S.^Merfme, also shows scattered warts on the column. That they are not real sucking warts is evident (compare also Stephenson, 1918b, p. 113), it stiU remains to be explained of which kind the warts drawn by Cocks are. For that reason I have examined the extended column of the specimen of B. longicornis from Ireland on stained surface prepara- tions, as well as on sections. It then became clear that the ectoderm of the column is not homogeneous. Over the surface there are namely scattered irregular spots containing numerous gland-cells and nematocysts, which are very sparse in the intermediate parts of the ectoderm. Probably it is these spots (possibly the intermediate parts) which Cocks has observed and which ought to appear more distinct when the column ACTINIARIA 143 has such a colour as on Cocks' figure, but wliich disappear when the column is pale flesh-coloured. I therefore think that there is no difference in the structure of the column of B. tuediae and longicornis. As also the nema- tocysts of the two species show a good conformity it seems to me that we have every reason to conjoin the two species. Another view is expressed by Walton (compare Stephenson igi8b, p. 113), who has seen both species aUve and who declares that they are quite "distinct." Also Stephenson (1918 b) beheved himself to have found some little difference between the two forms — perhaps partly owing to his having compared "Bolocera longicornis" from the Falkland Islands with B. tuediae. He thus pointed out that B. tuediae has a tendency to produce "humps of mesogloea at different points in its course." I have also observed such in a specimen of longicornis from Bohuslan. I cannot find any real differences between the two species, though I have examined the structure of the tentacles and the sphincter and the size of the stinging capsules in specimens from very different localities, also from North-America. The following table shows the size of the nematocysts and spirocysts in different parts of the body. The nematocysts in the apex of the tentacles are considerably longer than in the proximal part of the ten- tacles, the smaller specimens have shorter tentacular nematocysts than the larger specimens. columa tentacles : apex- tentacles : proximal part tt s/'. actinophaiyox DimensioDS of the column in cm Ingolf iSt. 27 - • 28 Lyngo (Kicr) Slcagerrak Bredefiord (-Rink-) »M. Sarsa igo2 St. 51. . . Bergeo Skagerrak Maine U. S. A OffBispen (Morten sen) Bergen (Grieg) Off Martha's Vineyard . , — (U. St. F. com.) North-America Verr Bohuslan 14 — 17 X 1,5 /i 14— rS X 1,5 17 — 19 X 1,5 15-17X r,5 17— I S.o. Iceland •M.Sars«St.24 -19 X i.S 18 — 24 X 1,5 ISX r,5 29 — 36 X 2,5-3/i 26 — 31 X 2,5 37-41 X 3—3.5 28—37x2,5—3 29 — 46 X 2,5 — 3 34— 4r X2,5 38—48 X 3 (60)65- 60- 60- 60- 72- 60- (72)82- 72- 87- 70- 77- 79- 84- 96- 72- 98- 96- 77 X3 j« 79 X 2,5—3 73 X»,5— 3 74 X 2-5,3 82 X2,s 77 X 3-3,5 113 X 2,5-3 96 X 3 112X3—3,5 109X2,5-3,5 106X3,5 103 X2,5-3,5 -106X2,5-3,5 ■127 X 3,5 127X3,5 ■118X3,5 -106 X 3,5 22 X 1,5—58x3,5 II 24 X 1,5-58X3—3,5 24 X I —62 X 3.5 22 X r,S — 67X2,5 29X2 — 77X3-(3,5) 24 X 1,5—74X3 26 X 2—65 X 2,5 43— 60X 3 n 36—50x2,5-3 43-55 X 2,5—3 58-73x2,5 53-62x2,5 65—72x3-3,5 53-74(96) X 3—3,5 62—77x3—3,5 58-72(82) X 2.5—3 58—72X2,5—3 70-86X3-3,5 (53)60-72X3 26X1,5-53X5/* 24 X 1,5—50X5 24 X 1—62X4,5 24 X 1,5—67X4,5 29X2— 77 X 5 29X2-77X5 29X2—77X4—5 46- -boXi.su 38- -50X3-3,5 46- 48- 46- 48- 50- 43- 46- -58X3-3,5 -58X3,5 -58X3.5 -{84 .') -62X2.5-3 -58X3,5-4 -60X3,5-4 53- -62X3-3.5 53- -60X3,5-4 (only 1: 1: : 1; 1,5 b: 2,5 small tentacles) 2,2 b: 1,5 2 b: 1,5 2 b: 2,5 3.3 3.5 4 4 3 3.2 3.3 5 6,5 7 : 8 b: 9,5 large spec. : 10 b: 8,5 The anatomy of this species was described by myself (1891, 1893) as to B. longicornis, and by Steph- enson 1918 b as to B. tuediae. I have not placed B. longicornis from the Falkland Islands (Stephenson 1918 a, p. 20) in the list of hterature, as I am not fully convinced that this species is identical with B. tuediae {longicornis), though it may possiblj^ be so. Bolocera multicornis Verr. Bolocera multicornis n. sp. Verrill 1879, p. 198. Andres 1883, p. 453. — — Verr., Mc Murrich 1893, p. 155. Haddon 1898, p. 430. Parker 1900, p. 351. Carlgren 1902, PI. 3, figs, i, 2, textfig. i, 2. Sagartia {Phellia) abyssicola, Koren and Dan. (p. p.). Danielssen 1890, p. 30, PI. 10, fig. 4. Diagnosis: Column low with distal part considerably broader than proximal part. Sphincter diffuse 144 ACTINIARIA without tendency to become somewhat circumscript, with close, high folds. Circular endodermal muscles of the column comparatively strong. Tentacles extraordinarily numerous, closely packed together, covering the greater part of the oral disc, short, longitudinally sulcated, conical to cylindrical and in the latter case rounded in the apex, all of about equal length. Well-developed aboral prolongations of the siphonoglyphes. Mesenteries of large specimens extraordinarily numerous. Perfect mesenteries, in comparison to the number of mesenteries, probably few. Oral stomata present; marginal stomata? Pennons of the mesenteries broad with palisade-shaped folds. Basilar muscles well-developed, fan-like expanded. Nematocysts in the ectoderm of the column, tentacles, and actinopharynx very numerous, those of the column 19 — 24 (28) X 1,5 — 2 /i, those of the tentacles 30 — 60 X (2) 2,5 fi in the apex and (19) 22 — 36 X 2 — 3 // in the proximal part, and those of the actinopharynx 31 — 47 (52) X 2,5^ — 3,5 //. Spirocysts in the extoderm of the tentacles numerous, from 22 X 1,5 // to 55 (60) X about 5 /i. Colour of the column and tentacles neafly uniform, bright redlead-coloured or orange-scarlet, niouthfolds a deeper shade of the same colour (Verrill). The tentacles of the Ingolf-specimens are dark reddish-brown in the distal parts. Dimensions in preserved state: Oral disc unto 16 cm, length of the column unto 6 cm, breadth of the basal disc unto 9 cm, length of the tentacles to about 4,5 cm. Occurrence: Davis Strait: 65°34' N. 54°3i' W. 68 fms. Bottom temp. 0,2 (Ingolf-Exp., St. 29), 66°35' N. 56''38' W. 318 fms. Bottom temp. 3,9° (Ingolf-Exp., St. 32), 68°2o' N. 54°03' W. 228—280 fms. (Tjalfe-Exp. 1908). In the neighbourhood of Bear Island 74°25' N. i7°36' E. 180 m (Olga-Exp., St. 49). Between Bear Island and Spitzbergen 75°4o'N. i7°io' E. 190 — 200 m (Olga- Exp., St. 55), 75°3i' N. i7°5o' E. 225 m. Bottom temp. i°6 (Norw. North. -Atl.- Exp., St. 326). 6i°i5' N. 9°35' W. 872 m (Thor-Exp., 1904, St. 99). Behring Island, 75 fms. (Vega-Exp.). Further distribution: North-America. Cape Cod 45 fms. (U.S. Fish Com.) 47°4o' N. 47°35'3o" W. 206 fms. (U. S. Fish Com.) (teste Verrill). A description of this species was given by myself 1902. The following table shows the size in // of the nematocysts and the spirocysts in some specimens. Habitat column tentacles : apex. sp. tentacles: proximal sp. actinopharynx Behring Isl Davis Str. (Ingolf) . . — (Tjalfe) . Olga Exp 19 — 24x1,5 — 2 19 — 24x1,5 38 — 60x2,5 34—50x2,5 30—53 X 2—2,5 52-60 29x1,5—55x4(5) 22x1,5—45x2,5 24— 31(39) X 2,5(3) 19 36 X 2-2,5 24—31 X 2-2,5 26x2 X 43x5(6) 24x1,5-43x5 37—47x3 —3.5 31—41x2.5—3,5 24—28 The size of the stinging capsules in the specimen from the Olga-Expedition is oiJy approximate 40—52 In addition to these species tentacles of a Bolocera species were taken during the Ingolf-Fxpedition at the stations 37 and 38 (6o°i7' N. 54°05' W. 1715 fms. Bottom temp. i°4, 59°i2'N. 5i°05' W. 1870 fms. Bottom temp. i°4). The nematocysts were considerably longer here than in very large specimens of B.tuediae. ACTINIARIA 145 In the apex of the tentacles the nematocysts show a size of 96 — 192 X 3,5 — 4,5 /i, in the proximal part 68 — 120x3,5 — 4 A*- Probably we have to do with a new species which provisionally may be named B. maxima. Fam. Cribrinidae s. Bunodaciiidae. Diagnosis. Basilaria with well developed pedal disc. Column sometimes smooth, sometimes with sucking warts or ampullaceous papiUae. Acrorhagi (bourses marginales) or pseudo-acrorhagi sometimes present. Sphincter strong, endodermal circumscribed. Tentacles short or of ordinary length, rarely with transversal swellings on their oral surface [Ixalactis). Mesenteries arranged after the number of 6, 8 or 10. Perfect mesenteries usually numerous. Acontia always absent. The genera belonging to this family must undergo a renewed revision. It is true that Mc. Murrich (1901) has made an attempt to give a more distinct definition of the genera of this family, but his attempt seems too provisional to me. Besides, the genera cannot be definitely limited until the family has been examined more particularly as to its anatomy. In liis pubhcation (1901) Mc. Murrich comprises 12 genera, 3 of which with an interrogation mark. Of these latter Tealiopsis must be completely excluded as, according to my examination, it is synonymous with Stomphia and therefore not belonging to this family. On the systematic place of TJielaciis^ and Physactis we cannot as yet set forth any opinion, as they have not been anatomically examined. The genus Gyractis^ is not identical with Cribrina, as Mc. Murrich thinks possible, but very likely with Anihopleura, and the genus Leiotealia must perhaps be dropped, based as it is on the presence of a smooth column, a character which it has in common with the older Epiactis of Verrill, as well as with Isotealia and partly with Urticina. It is, however, possible that it can be retained, but in that case the diagnosis of the genus must be altered and perhaps partly be founded on the appearance of the longitudinal muscles of the mesenteries which seem to differ from those in Epiactis. So far the genus must be regarded as dubious. The genus Isotealia is certainly a distinct genus and not synonymous with Leio- tealia, as Hertwig does not mention the presence of any perforated pseudo-acrorhagi in the latter genus (among others). Pseudophellia is not identical with Tealiopsis which latter does not belong to this family (compare above!), but, as far as I understand, with Epiactis. True enough, the column of Pseudophellia arctica, "the type of the genus, is covered by an adherent cuticle" (Verrill) , as, however, the column of the type of Epiactis, E. prolijera, which I have had the occasion to examine, is Umited towards the outside by a cuticle, though a very tliin one, and as it seems easily deciduous, there exists between the cuticle of Pseudo- 1 Thelaciis is probably a Bunodeopsis and not belonging to the family. 2 Unfortunately a control examination of the specimens, determined by Boveri as Gyractis, does not seem to be possible. I have not been able to distinguish with certainty in the Munich Museum the specimens examined by Boveri. In the collection of Dr. Ondaatje there are, however, a number of specimens externally exactly resembling Boveri's Gyractis — part of these specimens had been sectioned, probably by Boveri. These latter as well as the whole collection were badly preserved and the ectoderm almost in all places lost. On several specimens I could, however, find a great number of closely packed, large nematocysts in glycerine prepar- ations of the region of the acrorhagi. This indicates that there are true acrorhagi. As besides the sphincter was circumscribed the specimens must belong to the genus Aiithopleura. As also Boveri mentions acrorhagi ("Randblaschen") in Gyractis, there is no doubt that Gyractis is synonymous with Anthoplenra. The absence of directive mesenteries and siphonoglyphes in Gyractis possibly might serve to justify the establishment of a special genus; I do, however, think that it is unnecessary, above all because I am not fully con- vinced that Boveri's observations concerning the mesenteries are correct. Some of the above named Gyracits-shaped specimens, examined by myself, were furnished with 2 pairs of directive mesenteries. As Boveri's examination of the mesenteries seems to be somewhat superficial, it will be advisable to accept with caution his statement of the absence of directive mesenteries and siphono- glyphes in the genus Gyractis. The IngoIf-ExpeditioD. V. 9. " c ACTINIARIA 146 ■phellia and that of Epiactis only a difference in degree, in as much as the cuticle is stronger in the former species, weaker in the latter. As Epiactis and Pseudophellia agree in other characters too, Pseudophellia, which is synonymous with the older Epiactis, may be dropped, and the type of Pseudophellia be called Epiactis arctica. Cribrina, Urticina and Ixalactis are, to my mind, rather well defined genera. Whether Epigonactis is synonymous with Urticina or not is, however, very dubious and cannot be decided until the genus has been subject to a careful anatomical examination — I have before (1901 p. 483) placed this genus together with Epiactis, and Stephenson (1918 a p. 27) was of my opinion. Finally I do not think that Anthopleura and Bunodosoma, which Mc. Murrich has placed together to a single genus, are identical. As far as I can see from Mc. Murrich's description of the verrucae of Anthopleura xantogramma and A. (Au- lactinia) stelloides they are in structure like those of Cribrina and Urticina and are real suckers to which foreign bodies are attached, while the ampullaceous off-shoots in Bunodosoma are constructed in a different way, and, according to my examination, more in accordance with the prominence of the column of Phymactis and Cystiactis. Thus the ampullaceous off-shoots of the column of Bunodosoma are not suckers, but rather to be considered as weak batteries of nematocysts to which no foreign bodies are attached. Mc. Murrich (1889 p. 24) himself has emphasized this difference, but later on (1901) not made use of it for systematic purposes, in which he was mistaken, as far as I can understand. The characters which distinguish the genera of this family from each other are first of all based on the presence of acrorhagi, further, on the occurrence or non-occurrence of real suckers and ampullaceous batteries of nematocysts on the column, on the exterior of the tentacles and the arrangement of their long- itudinal muscles and of the radial muscles of the oral disc, on the distribution of the reproductive organs in the mesenteries and on the arrangement of the latter. The importance of these characters to the classification however wants further discussion. The absence or presence of acrorhagi is no doubt a good character, as no variation occurs within the genera in this respect, but these characters are either present or absent in the respective genera. On the other hand, the systematic importance of other differentiations of the column is partly totally different. It is true that the ampullaceous papillae are characteristic of Bunodosoma and always present here (as in Anthopleura this genus is characterised through the presence of acrorhagi), but the appearance of suckers is evidently subject to variation, in as much as the same genus and the same species now have suckers, now are devoid of such. This is the case with Urticina. It is also possible that the below described, new genus Cribrinopsis, which is typically furnished with suckers, sometimes is devoid of them. The absence of discernible suckers in strongly contracted and badly preserved specimens should not, however, absolutely be interpreted as if suckers were in reality lacking, the suckers of such specimens not being easily discernible to the naked eye, not even under high magnifying powers. Thus it is only with great caution that we may use the presence or absence of sucking warts as a systematic character, as mentioned before by Mc. Murrich. In the other genera, Cribrina and Anthopleura, the occurrence of verrucae seems to be constant, wlrile the genus Epiactis is always devoid of verrucae. The longitudinal muscles of the tentacles and the radial muscles of the oral disc are now mesogloeal, now ectodermal and commonly constant in the respective genera, though also here a certain variation some- ACTINIARIA 147 times takes place. Concerning the former they seem to be almost exclusively' mesogloeal in Cribrinopsis; in Urticina they variate, as I wiU show below, from ectodermal to meso-ectodermal or ecto-mesogloeal, and this even in the same species. In the other genera these muscles are ectodermal or meso-ectodermal as in Cribrina elegantissima and spetsbergensis. It is exactly the same with the radial muscles, though they are never as much enclosed in tlie mesogloea as the longitudinal muscles of the tentacles. Commonly they are ectodermal, in the genera Cribrina and Urticina ectodermal or meso-ectodermal, in the latter case they agree with those of Cribrinopsis. In Urticina they variate from ectodermal to meso-ectodermal in the same species. Concerning the distribution of the reproductive organs in the older mesenteries, the genera Isotealia and Urticina differ from the other genera. In Urticina, according to its age, only the 6 first pairs of mesen- teries, or the 10 or 20 oldest mesenteries are sterile (compare below), while in Isotealia the reproductive organs first appear on the mesenteries of the third cycle. The other genera have reproductive organs, as far as we know, even in the mesenteries of the first order which remain fertile. The arrangement of the mesenteries as a genus character is of more secondary significance, as it varies considerably especially in certain genera, even in species such as Cribrina and Cribrinopsis. On the other hand the mesenteries are in the other genera more typically, hexamerously arranged, while the genus Urticina shows decamerism. Especially concerning the latter genus the question has been raised, whether the decamerism may be used as a genus-character. Mc. Murrich (1901 p. 21) namely declares; "to establish a genus on its decamerism seems to me .... to place it on an exceedingly insecure foundation." He founds his statement, for one, on an information by Verrill that "many Urticina crassicornis are hexamerous, many others decamerous, some octamerous and a few irregularly or unequally developed on opposite sides." If that really is so, the decamerism is here certainly worthless as a genus-character. At present I, however, much doubt that Ver rill's identifications of the genus have always been correct. As we wiU see from the following it is very difficult, without the most careful investigation, to distinguish the genus Urticina from another genus, Cribrinopsis, and young specimens of Urticina likewise from Cribrina. I for my part have almost always found Urticina decamerous (only a single time octamerous), though irregularities occur, so that not all mesenteries of tlie same cycle may be developed. There is, besides, nothing astonishing in this that the arrangement of the mesenteries in an early period of its hfe displays a variation, as Urticina during its development passes through a hexamerous stage. To my mind the decamerism may be used as a genus- character to Urticina, though with a certain restriction. Decamerism, octomerism and hexamerism princip- ally may be used as genus-characters. Certain genera (and species) namely have a more constant mesenterial arrangement than other genera, wherefore the arrangement is usable here as a systematic character, while other genera show so great a variation in the grouping of their mesenteries that the mesenterial arrangement is useless for systematic purposes. Of course we must leave out of consideration accidental defects of the mesenteries causing any kind of disorder to the typical arrangement. There can, for instance, be no doubt that the arrangement of the 8 " Edwardsia-iaesenteries" is of great systematic importance, though in the Milne-Edwardsinae only 7 mesenteries exceptionally occur (p. 64 compare a similar suppression of mesenteries in a young Peachia p. 105). Finally it must be proved in each special case if the decamerism, the octomerism etc. is due to regeneration, in which case it is of no systematic importance, as I have before pointed out (1914 p. 63). 19* g ACTINIARIA The identification of the Arctic and North-American Cribrinidae has till now been rather difficult. True enough, it is easy to distinguish Crihrina stella from other forms, though alcoholic specimens of this species have possibly been confounded in the literature with the below described C. spetsbergensis, but some of the other forms, especially specimens without reproductive organs, agree so weU with each other that in certain cases it is almost impossible to distinguish them, if we do not make use of the dissimilarity of the nematocysts as a means of identification. Through a systematic examination of the size of the nematocysts in a great number of specimens I have, however, been able to distinguish several Cribrinids which have certainly been more or less confounded with each other by several authors, myself not excepted. After having laid a sure foundation through a study of the size of the nematocysts I have, little by httle, found other char- acters usable as distinctive marks to the different genera and species. The importance of a closer study of the nematocysts in order to classify the Actinians — which I have several times emphasized — stands out here in the most striking manner. » Whether any of the species, mentioned below by myself, have been described before can hardly be decided as the North-American Cribrinids are more or less imperfectly known, especially as regards their nematocysts. No satisfactory answer can be given to this question, until the nematocysts of the North- American forms have been subject to closer examination. Genus Cribrina Ehr. s. Bunodactis Verr. Diagnosis: Cribrinidae with a well developed pedal disc. Column with suckers (verrucae), arranged in more or less distinct lines, without true acrorhagi, sometimes with pseudo-acrorhagi. Sphincter strong. Tentacles from short to of ordinary length, simple, like the mesenteries hexamerously arranged, in certain species after another number or irregularly arranged. Longitudinal muscles of the tentacles and radial muscles of the oral disc ectodermal, sometimes with a tendency to be a little mesogloeal. Most often 2 distinct siphono- glyphes. Numerous perfect mesenteries. Reproductive organs on the first cycle (sometimes not developed on the directive mesenteries) and on the other stronger mesenteries. In my paper 1899 I have put forms furnished with real acrorhagi together with Cribrina. That is however not right, but such species as Bunodes hermafroditica might be referred to Anthopleura. Whether such species, having pseudo-acrorhagi, belong to Cn'finwa ox to Anthopleura , is difficult to decide. Mc.Mur rich refers them to Cribrina, and for the present I do the same, though it would perhaps be more correct to arrange them with Anthopleura, as the pseudo-acrorhagi may be regarded as beginning acrorhagi. Cribrina stella (Verr.) Mc. Murr. PActinia coriacea Stimpson 1853 p. 7. Bunodes stella n. sp. Verrill 1864 p. 16. PI. i figs, i — 8, 1868 p. 258. Andres 1883 p. 447. Parker 1900 P- 752. Bunodactis stella (Verr.) Verrill 1899 p. 43. Cribrina stella (Verr.) Mc. Murrich 1910 p. 76 PI. 3 figs. 6 — 7. Bunodactis spectabilis Verrill 1879 a p. 15, 1879 b p. 152. ACTINIARIA 149 Diagnosis: Body generally cylindrical or columnar, its height often double its diameter. Column with well-developed verrucae in the upper part. Tentacles 40 — 48. Sphincter of the palmate or mixed type. 2 siphonoglyphes. Mesenteries hexamerously arranged in 4 or 5 cycles, more numerous than the tentacles, the first two cycles perfect. Ivongitudinal muscles of the mesenteries well-developed, forming distinct, diffuse pennons. Parietobasilar and basilar muscles rather well developed. Nematocysts of the tentacles (17) 22 — 31 X 1.5 — 2.5 jx, those of the actinopharynx 24 — 38 X 3 — 4.5 fi. In the latter also nematocysts with distinct basal part to the spiral thread 24 — 31 X 3.5 — 5 fi in size. Nematocysts of the column 17 — 19 x 1.5 fi. Spiro- cysts of the tentacles from 13 x i /i to 31X 2/1. Colour olive-green or brown, sometimes flesh-coloured. Tentacles translucent greyish or brownish with an opaque white spot at the base and a faint whitish chevron mark about half-way between the tips and the base. The disc brownish, in young individuals opaque white bands radiating towards the bases of the primary tentacles. Actinopharynx white, inside of the mouth light orange (Verrill, Mc. Murrich). Colour green (Dons). Dimensions unto 5 cm in length in extended state (Verrill). Occurrence: North America: New Foundland's bank 46°5' N. 5i°44' W. 56fms. , sand, shells (Ingegerd-Gladan-Exp. 1871 J. I,indahl). North Greenland: 25 fms. (Torell). West Greenland: Upemivik 34 fms. (Ingegerd & Gladan-Exp. 1871), Disco fiord (The Danish Arctic station 1898), Disco bay 3 — 25 fms. (Holm 1886), Godhavn (Ammondsen 1872), Claushavn (Oberg 1870), Godthaab littoral (Ryder 1883), Frederikshaab (Lundbeck 1889), Nordre Stromfiord littoral (Nordmann 1911), Holstens- borg (Traustedt 1892), Store Hellefiskebanke 18 fms. (Holm 1886). East Greenland: 72°2o' N. 2i°2o' W. 70 m. (Sw. Greenland-Exp. 1899), Tunok Angmagsalik 65°53' N. (Kruuse 1902), Tasiusak 25 — 30 fms. (East Greenland-Exp. 1899). Iceland: Berufiord 3 fms. Uttoral, Skerja fiord, littoral (A.C. Johansen 1900), Styk- kisholm httoral (A. C. Johansen. 1900), Djupivogur littoral (A. C. J oh. 1900). Iceland without distinct locality. West Spitzbergen: Smeerenberg bay 4 — 10 fms. (1868), Treurenberg bay 6 — 30 fms. (1881), Icefiord, Klas Billen bay 32 — 40 m (Sw. Spitzbergeu-Exp. 1908), Axel Isle, Bel sound (1910). East Spitzbergen: I,omme bay 10 fms. (Sw. Spitzbergen-Exp. 1861), Great fiord. Cap Blanck 65 m. (Romer & Schaudinn 1898 St. 5), Whales point 20 — 30 fms., clay (Malmgren 1864). Norway. Finmark: Vadso littoral (Sandeberg 1877), Porsanger fiord, Uttoral (Michael Sars-Exp. 1900), Nordkap (Verkriisen 1875), Kjosen 150 ACTINIARIA in Ulfsfiord, littoral (1861), Grotsund littoral (1861), Tromso littoral (Kier 1902, Dons 1910, 3 m, Dons 1912), Gibostad 3 m (Dons 1912), Sorvaer (Ohlin 1890). Kola peninsula: The Russian biological Station, Kolafiord (Derjugin 1906), I,adi- gano, Cliewanna 30 fms. (Sandeberg 1877), Vaideguba littoral (Sandeberg 1877), Semiostrowa 50 — 55 fms. (Sandeberg 1877), lyitsa (Sandeberg 1876), Scharetskaja (lyilljeborg 1848). Kara Sea: Jugor Shorr off Chabarova 5 — 8 fms. (Vega-Exp.). Arctic Sea of Sibiria : 20' off Cape Jakan 12 fms. (Vega-Exp.), 2 miles north of the winterharbourof the Vega 67°4'4g"N. I73°23'2" W. (Vega-Exp.), Behring sound 67°4' N. I73°24'6" W. 7 — 9 fms. (Vega-Exp.). Further distribution. North America. Arctic ocean to Cape Cod (teste Parker). Cape Elisa- beth Me., Eastport Me., Grand Menan N. B.in crevices of rocks near low-water mark, Cumberland Bay (teste Verrill), Passamaqvoddy Bay St. Andrews on rocks (teste Mc. Murrich). From Maine to Greenland (teste Verrill). The anatomy of this species has been described before by Mc. Murrich (1910), wherefore I find a recapitulation unnecessary, but will add some supplementary remarks to his description. The longitudinal muscles of the tentacles are ectodermal and resemble those of C. spetsbergensis, described below, the muscle folds however show no tendency here to be mesogloeal. The radial muscles of the oral disc are a little weaker and ectodermal (verified on several specimens). In 8 specimens collected from different locahties, among others from Eastport, I have more closely examined the sphincter. In all specimens it was of a palmate type. In no case the secondary lamellae issue from any distinct main lamella — in a specimen from Frederikshaab there is, however, an indication of a main lamella. Now the sphincter was more broad with distinct palmate extension of the lamellae, now it was more narrow and composed of several very thin main lamellae. Mc. Murrich' s figure (1910 PI. 3 fig. 7) of the sphincter probably is not typical as it shows a pinnate appearance with a thick main lamella. In the textfigure 159 I have reproduced the sphincter of a specimen from Wales point. The verrucae were commonly distinct, in some specimens (from Discofiord, Porsangerfiord and North Cape) indistinct, owing to a bad state of preservation or to a strong contraction of the column. The number of mesenteries variates from 24 to 48 pairs, that of the tentacles in the specimens examined by myself from 40 — 48. The mesente- ries thus are more numerous than the tentacles. The mesenteries of the last cycle are developed in the proximal part of the body and grow from here in oral direction, but do not reach the distal end of the column. ^ "If . ^' ^^f' In order to show the constancy of the size of the nematocysts, I Cnbnna stella. Transverse section of sphincter. give here the following table. ACTINIARIA 151 Habitat uematocysts spirocysts of the tentacles typical nem actinopharynx nem. with visible thread. number of tentacles number of 'mesenterial I pairs 73 Eastport — (small spec.) . Discofiord Frederikshaab Nordre Stromfiord . . . Angmasalik Berufiord Bell Sound Porsangerfiord Nordkap TromsB Gibostad Coast of Murman .... Kola. Chewanna Winter harbour of Vega 24 — 29 X 2 u 20 — 26 X 2 20 — 26 X 2 20 — 26 X 2 17 — 24X2 22 — 29 X 2 — 2,5 24—31x2—2,5 22 29 X 2 24—31X2(2,5) 22 25 X2 22 26X2(2,5) 22 26 X (1,5) 2 22 29 X 2 22 — 29 X (1,5)2 (19)22 — 26 X (1,5)2 22 26 X 2 24 — 29x2 2,5 23 29 X 2 — 2,5 22 — 26X2 22 — 29 X 2 2,5 18x1- 13X1- 15X1- 17X1- 17 X I- 17X I- 17X1- -31X2^ -31X2 -19? X2 -29 X 2 2,5 -31X2 -31x2 -24X2 -24X2 -26x2 -29x2 -26x2 31— 36x3— 3,5 u (24 X 2)29—34 x 2,5—3,5 29 — 36X2—3,5 29—36X3—3,5 24—30 X 3—3.5 29 — 36 X 4 30—36x3,5—4,5 29 — 36 X 3 30—38 x 3—3,5 29—36(38) X 3,5 26—31 X 3—3.5 29—37 X 3 29 — 36 X 3 29—34(36) X 3(3.5) 31—36 X 3 29—35 X 3—3.5 30—37x3—3,5 29—37 X 3—3.5 31—36x3 24—31 X 3.5—5 22—24 X 3.5—5 46 40 48 46 23 + 21 12 + 12 24 + 24 the half 22 As we see, the size of the nematocysts and the spirocysts agrees well in the different specimens. The neniatocysts of the column are shorter than those of the tentacles, in five more closely examined specimens 12—14 X 1,5 //, 12—14 X I /z; 18—23 X 1,5— 2 //; 17—19 X 1,5 n, 20—23 X 2 //. Mc. Murrich has found embryos in the coelenteric cavity in May, I myself in June, July, August and October. Cribrina spetsbergensis (n. sp.). PI. 2. Fig. 2. Rhodactinia crassicornis (O. F. M.) var. spcisbergensis Carlgren 1902 p. 39, textfig. 3. PLeiotealia spetsbergensis n. sp. Kwietniewski 1898 p. 134 (pro parte). Diagnosis: Column with commonly rather small verrucae, at least in the upper part. Sphincter palmate or pinnate. Tentacles in variable number unto 96, tliick, cylindrical, in contraction smooth or more seldom longitudinally sulcated, at most as numerous as the mesenteries, aU of about equal length. Longitud- inal muscles of the tentacles well-developed with in general high folds, principally ectodermal, but at the base of the folds and sometimes at their apex in small parts enclosed in the mesogloea. Radial muscles of the oral disc like the longitudinal nmscles of the tentacles but more enclosed in the mesogloea. Mesenteries of variable number unto 49 pairs, commonly hexamerously but often irregularly arranged, so that not all me- senteries of the last cycle are developed. Muscles of the mesenteries strong, especially the longitudinal and the parietobasilar muscles. Reproductive organs on all the stronger mesenteries, sometimes also on the directives. Nematocysts of the tentacles (24) 26—42 X 2—3 /i, those of the actinopharynx (34) 36—53x3,5—5 ft, spiro- cysts of the tentacles (18)22 X i— 1,5 to 53 X 2,$ ;jt. Colour? ACTINIARIA Dimensions: Specimen from Behring Sound (PI. 2 fig. 2) in contracted state: Height 3 cm, largest breadth about 6 cm. Length of the tentacles 0,8 cm. — Specimen from New Foundland: largest breadth 7 cm, height about 3,5 cm. Occurrence: New Foundland (Verkriizen 1876). Greenland without distinct locality. Between Iceland and Faroe islands 64°07' N. ii°i2' W. 237 fms. Temp, at the bottom 2°,5 (Ingolf-Exp. St. 4). 76°23'N. I5y E. 145 m (Olga-Exp. St. 41). 74°55' N. i7°3o' E. 180—135 m (Olga- Exp. St. 52). 64°53' N. io°o' E. 630 m. Temp, at the bottom — 0,69° (Michael Sars-Exp. 1900 St. 10). 62°35' N. 4°4' W. 620 — 640 m. Temp, at 620 m. — o°,03 (Michael Sars-Exp. 1902 St. 67). - Norway. Finmark (Kolthoff). Behring Sound 67° N. 173° W. 9 — 15 fms. (Vega-Exp.). Exterior aspect. The exterior of the body much recalls that of Urticina. The pedal disc is wide and the length of the column in contracted state shorter than the diameter. On the column there are long- itudinal lines of verrucae, which are probably always present in the upper part. Whether the verrucae are developed also in the most proximal part of the column I cannot decide , as the specimens were strongly contracted in this region and partly not well preserved. On most specimens the verrucae were distinct. In some specimens (from the Michael Sars-Expedition and in one specimen from New Foundland the verrucae were very indistinct or inconspicuous, and it is questionable if the species sometimes is devoid of verrucae, a question, which is very difficult to answer, as it regards strongly contracted and badly preserved material. The verrucae are commonly not as large as those of Urticina felina coriacea. A distinct fossa is present. The tentacles are short, cyUndrical, all of about the same length, smooth or sometimes with shallow to rather deep longitudinal furrows, and a little flattened in the apex. The arrangement of the tentacles probably varies considerably in the outer cycles, as the number of the tentacles (like that of the mesenteries) is very indistinct, in the inner cycles the number of 6 may be prevalent. The smallest number of tentacles was 34, possibly 36, the greatest 96. The number of tentacles corresponds to that of the mesenteries or is a httle smaller. The oral disc is wide. The two siphonoglyphes are broad and furnished with well-developed aboral prolongations. The actinopharynx is long and has longitudinal folds in great numbers. Anatomical description: The ectoderm of the column is high and contains numerous mucus- cells. The nematocysts of the column are smaller than those of the tentacles, in the specimen from Finmark the size was 17 — 22 x 1,5 — 2 //, in the other examined specimens from four localities the size varied from 22 to 31 X 2 — 2,5 11. The verrucae are of the same appearance and structure as in Urticina felina coriacea (compare below!). The mesogloea is thick and fibrillary with numerous, scattered, protoplasma-poor cells. The endodermal circular muscles are well developed. The structure of the sphincter is rather variable. In the most closely examined specimens it was of a palmate type, in two specimens of a pinnate one. In the ACTINIARIA 153 textfig. 164 I have reproduced the pahnate sphincter of the specimen from the Olga-Expedition St. 41. A similar sphincter is developed in the specimen from Finmark. In the specimens from the station 4 (Ingolf- Exp.), and from Greenland, in one specimen from the station 67 (Michael Sars-Exp.) and in one individuum of Leiotealia spetsbergensis the sphincters are of decidedly palmate tj^je without a distinct main lamella. A pinnate sphincter with a thin main lamella is present in the reproduced specimen from Behring's Sound textfig. 16 j) and in a specimen from the station 25 (Michael Sars-Exp.). As transition stages between the Fig. 160 Fig. 161 Fig. 162 Textfigs. 160 — 164. Cribrina spelsbergensis. Transverse sections of tentacles (figs. i6o, 161), of oral disc (fig. 162) and of sphinc- ters (figs. 163 — 164). (Fig. i6o spec, from St. 52 Olga-Exp. ; figs. 161, 163 spec, from Vega-FIxp. ; fig. 162 spec, from St. 67 M. Sars-Exp.; fig. 164 spec, from St. 41 Olga- Expedition). Fig. 163 pinnate and palmate type we may consider the sphincters of a specimen from the station 52 (Olga-Exp.) and of an individuum from New Foundland. In the former there is a very thick main lamella, but not so long that we may regard the sphincter as palmate, in the latter the main lamella is thin at the base, but much expanded inwards and forming a thick irregular triangle. In the sphincter, reproduced on the textfig. 163, streaks of muscle meshes are seen in some places. Such mesogloeal streaks in the spliincters indicate that parts of the mesenteries have been sectioned. All endodermal spliincters as well as the endodermal muscles in common become mesogloeal at the moment when they break through the mesenteries. The ectoderm of the tentacles is high and contains numerous nematocysts and very numerous spiro- cysts. The size of the nematocysts in the tentacles and in the actinopharjmx and of the spirocysts in the tentacles is seen from the following table, in which also the number of tentacles and pairs of mesenteries and the distribution of the reproductive organs on the directives are stated. The Ingolf-Expedition. V. g. 154 ACTINIARIA Distribution of Habitat Tentacles uematocysts spirocysts Actinopharynx nematocysts Number of tentacles Number of mesenterial pairs the tive the reproduc- organs on directives New Foundland 31—38x2,5/1 19X1,5 — 48x2/* 36—43x4.5—5," 82 22 + 23 cJd + — — 31—36x2 29—34 X 2 26 — 36 X 2 24 X 1,5 — 53 X 2 2,5 —48x2 41—50x3.5 41-48x3.5 41—48x3.5 77 96 19 + 21 24 + 27 23 + 24 1 (J ■A 0 Ingolf-Exp. St. 4 Pinmark 29 — 36 X 2 24— 31(34) X 2 26 — 36x2 — 2,5 24 29 X 2 —43x2 22X1,5 43X2 36—43 X 3.5—4.5 36—46 X 4—5 38—43x4,5—5 34—41X3—3.5 88 34 (possibly 36) 36 22 + 23 9 + 9 9 + 9 cJd+ Greenland (small sp.) . "Michael Sars" St. 67 . 34—41 X 2,5—3 24X2 53X2,5 43—53 X 4—5 80 20 + 20 - easily confounded. They are distinguished from one another by the distribution of the reproductive organs on the mesenteries, and by the different relation of the nemato- cysts in the tentacles to those of the actinopharynx. If it were to be found out in future that Urticina in its first adultness has reproductive organs also in the mesenteries of the first cycle, which I hold improbable (compare Urticina felina p. 167, 168, 174), and that these reproductive organs are later on reduced, the only important difference between the two genera lies in the above named different size of the nematocysts. Under such circumstances it is possible that we must drop the above genus and place it together with Ur- ticina. So far, we have every reason for preserving it. Gribrinopsis similis n. sp. (PI. 3- Fig- 7)- Rhodactinia crassicornis (O. F. Miill.) pro parte Carlgren 1902 p. 39 textfig. 6. PUriicina crassicornis (O. F. Miill.) and Rhodactinia Davisii Agas. pro parte. Auctorum. Actinostola abyssorum Carlgr. Pax 1915. Diagnosis: Pedal disc wide. Column at least in the upper part with verrucae (sometimes incon- spicuous or not present?) Sphincter pinnate to palmate. Tentacles in larger specimens from 64 to 90, com- monly almost as numerous as the mesenteries, the inner longer than the outer; thick, cylindrical or a little conical, more robust than those of Urticina, in contracted state irregularly wrinkled or longitudinally sul- cated with numerous transversal folds. lyongitudinal muscles of the tentacles very strong, mesogloeal meshes fine, radially extended. Radial muscles of the oral disc strong between the radial furrows, in the furrows feeble, mesogloeal muscles fusing into the ectodermal muscles. Mesenteries commonly decamerously, more seldom hexamerously, sometimes a little irregularly arranged. Nematocysts in the ectoderm of the tentacles 34 — 70 x 2 — 2,5(3) A*, i" fiat of the actinopharynx 36 — 67(70) X 3,5 — 5 fi. Spirocysts of the tentacles of variable size from 19 x 1,5 to 67 x 3 ^. Colour? Dimensions: The size of some of the largest, strongly contracted specimens was the following: i) Spec, from Ikamiut: largest breadth 9 cm, height about 3 cm, length of the inner tentacles about 1,7 cm. 2) Spec, from Behring's Sea: largest breadth 8,5 cm, height 7 cm, length of the inner tentacles 3,5 cm, that of the outer 2 — 2,5 cm. (The tentacles were not strongly contracted). Occurrence: New Foundland ? (The bottle, containing also several Urticina was labelled Green- land and New Foundland). West Greenland. Ritenbenk 15- — 20 fms. (Oberg 1870) (Traustedt 1892), Godhavn 70 fms. (Torell). Claushavn 10 — 15 fms. ; 20 fms. (Oberg 1870). Christianshaab 15 — 30 fms. (Oberg 1870), Ikamiut (L,ohmann 1905). Egedesminde (Traustedt; BergendaliSgo). NordreStrom- fiord 14—38 m. (Nordmann St. 3 b). Sukkertoppen 15 — 26 fms. (Oberg 1870, Holm and others), Fiskenses 63° N. 5i°io' W. 150 fms. (Ammondsen). Bredefiord 170 — 180 fms. (Rink- ACTINIARIA 157 Exp. 1912), Ikertokfiord 5 — 20 fms. (Holm 1886). St. Hellefiske- banke 18 fms. (Holm 1886). 69°46' N. 5i°22' W. 250 fms. (Tjalfe- Exp. 1908 "/, St. 155). Greenland without distinct locality. West Spitzbergen: Treurenberg bay 6 — 30 fms. (Sw. Spitzbergen-Exp. 1861). Bell Sound Duyn Point 36 fms. (Sw. Spitzbergen-Exp. 1872 —7i). 30—40 fms. (Torell). East Spitzbergen: Foster Isl. 40 fms. (Sw. Spitzbergen-Exp. 1861). W. Thymen strait 38 m, King Charles land between Jena and Abel islands 40 m, Bismark strait 35 m, Ryk-ys islands 60 — 80 m (Romer & Schaudinn 1898 St. 47, 32, 45, 49). North Atlantic: 62°35' N. 4°4' W. 620 m. Temp, at the bottom — o°,03 (Michael Sars-Exp. 1902 St. 67). 62°27' N. I3°27' W. 150 m. Temp, at the bottom probably 4°5 (Michael Sars-Exp. 1902 St. 91 (only tentacles). Faroe islands (Miiller 1900). Norway. Finmark. (Kolthoff). Murman coast: 75 — 120 fms. ("Alexander Kowalewsky" St. 191, 218 1909, teste Pax = Actinostola abyssoruml). Kolafiord, without distinct locality teste Pax = A. abyssoruml). Kolafiord (The Russian biological station Derjugin), Chewanna 30 fms. (Sandeberg-Exp. 1877), Orafiord. Behring Island 75 fms. (Vega-Exp. 1879). Corea strait 65 fms. ("Store nordiske" 1890). Exterior aspect: The pedal disc is wide. The body is, according to the state of contraction, cylindrical, conical or flattened, in contracted specimens the height of the column is commonly shorter than the diameter of the base. The column is furnished with lines of verrucae which appear more or less distinctly, according to the state of contraction. In a part of the specimens I have not been able to verify with certainty the presence of verrucae, it may be possible that such ones are sometimes lacking, which is very difficult to determine in contracted and badly preserved material, above all as the verrucae are rather small. I have, however, obser\-ed that the verrucae become inconspicuous by a strong contraction of the column. As an instance I can adduce that a specimen with very distinct, though small verrucae on a great part of its circum- ference shows no trace of verrucae in the remaining, strongly contracted part. If the specimen had been strong- ly contracted in all places, it would have been considered to be devoid of verrucae. On most specimens there were however distinct verrucae. How far they expand on the column I cannot with certainty decide. On some specimens I have observed them only in the distal part, on others the distribution of them was considerably more extensive, the most proximal part is, however, probably always devoid of such. There is a well marked fossa. Acrorhagi and pseudo-acrorhagi are wanting. The tentacles variate a little in number in the examined specimens. Excepting a small, not adult specimen with only 45 tentacles, the others had from 64 to 90 tentacles 158 ACTINIARIA (compare the table). To judge from the grouping of the mesenteries the tentacles are commonly decamerously arranged, though a hexamerous arrangement also seems to occur. They are cylindrical or in more extended state a little conical, more robust than in Urticina, and in contracted state irregularly folded or longitudinally sulcated with numerous transversal folds and with a distinct opening in the apex (PI. 3 fig. 7). The outer ten- tacles are considerably smaller than the inner (about half as long). At the entrance to the siphonoglyphes there are conspicuous gonidial tubercles, the siphonoglyphes are well marked and furnished with well developed aboral prolongations. The actinopharynx is long and has longitudinal folds in great numbers. Anatomical description: The ectoderm of the column is high and contains nematocysts 17 — 25 X 2 /^ in size, in the specimen from Finmark the nematocysts were a little longer (23 — 30 X 2,5 (i). The verrucae seem to be of the same structure as those of Urticina. The mesogloea is thick and contains rather numerous, protoplasma-poor cells. The endodermal circular muscles is rather well developed. The sphincter is strong, pinnate or palmate. Two examined species were furnished with such a sphincter, as the textfig. 165 (specimen from Finmark) shows, viz. with a strong main lamella, tliickening inwards; in a specimen (from the Corea strait) the sphincter was distinctly palmate without a main lamella. A specimen from Kola, Chewanna had a sphincter with a short and thick main lamella (textfig. 166). The ectoderm of the tentacles is high and contains numerous nematocysts, which in the apex reach a size of 34 — 70 X 2 — 2,5 (3) //. They are of the same length as those of the actinopharynx, but the latter is considerably broader (about double as broad). The size of the nematocysts and spirocysts from part of the material is given in the following table, in which also a survey of the variation of some other organs has been included (p. 160). The longitudinal muscles of the tentacles are very strong, almost entirely enclosed in the meso- gloea, and separated from the ectoderm by a commonly thick mesogloeal lamella. Towards the ectoderm the mesogloea projects into fine, sometimes ramificating off-shoots, between these there are sometimes (al- ways?) solitary muscle-fibrils, never forming any coherent layer. These muscles are considerably thinner than those enclosed in the mesogloea and are probably in a state of reduction. The muscle meshes are in contracted tentacles radially extended, they are sometimes rather large (textfig. 167 specimen from Finmark) but commonly densely packed together (textfig. 168). Still denser meshes may occur. The radial muscles of the oral disc are not so much enclosed in the mesogloea as the longitudinal muscles of the tentacles, but the muscles here may commonly be designated as ecto-rnesogloeal. Between the insertions of the mesenteries they have commonly the appearance as the textfigure 169 shows, sometimes the meshes are smaller. At the insertions of the mesenteries the muscles are weaker and commonly not so enclosed in the mesogloea as it is in the middle part between the insertions, and here it is sometimes chiefly ectodermal. The ectoderm of the actinopharynx contains numerous nematocysts of about the same length as those of the tentacles, but in breadth they are considerably larger. The size variates between 36 — 67 (70) x 3,5 — 5 //. The number as well as the arrangement of the mesenteries variate. The most closely examined spec- imens had 40 or about 40 pairs of mesenteries decamerously arranged (10 + 10 + 20; 10 + 10 + 20 + i). In the two largest specimens the mesenteries were hexamerously arranged, in the specimen from Behring's Sea the number of mesenteries was 46 (6 + 6 + 12 -|- 22), on one side all the mesenteries of the 4th cycle ACTINIARIA 159 v/ere developed, on the other side two mesen- teries of the 4th order were lacking. In the specimen from Ikamiut the number was 55 (6 + 6 + 12 + 24 + 7 — compare the table) . The arrangement of the mesenteries thus seems commonly to be deca- merous, though it may happen to be hexame- Fig. 165 rous. All mesenteries were perfect in the lar- ger specimens, in the smaller specimens the last cycle was not connected with the actinopharynx . The number of mesenteries seems sometimes to he a little smaller than that of the tentac- les, which indicates that also here the mesen- teries grow from the basis upwards, a rule, which perhaps holds good for all Cribrinids. The longitudinal muscles of the mesenteries recall those of Urticina, and the pennons appear as bands, a little but deeply folded. The parie- tobasilar muscles are well developed, though not as strong as in Urticina. The uppermost part is Fig. 168 Fig. 169 Fig. 167 Textfigs. 165 — 169. Cribrinopsis siniilis. Transverse sections of sphincters (figs. 165, 166), of tentacles (figs. 167 — 168 and oral disc (fig. 169). (Figs. 165, 167, spec, from Finmark; fig. 166 spec, from Kola, Chewanna; fig. 169 spec, from Corea strait). rather narrow, and the muscles end before reaching the region of the sphincter. The basilar muscles are well developed and discoverable to the naked eye. Oral stomata are present, sometimes also marginal stomata, the latter, however, occur anytliing but regularly. All mesenteries are fertile, only on the directive mesen- teries they are often lacking (compare the table p. i6o). The species is dioecious. Remarks. In this specimen I have never found any embryos in the coelenteric cavity. The most closely examined specimens were however male. A specimen was a double animal, each specimen had two pairs of directive mesenteries symmetrically arranged, perpendictdarly to the div-iding plane. The small fragments of the oral disc with tentacles, which Pax 1915 has determined as Actinostola abyssorum, certainly do not belong to this species but to Cribrinopsis similis. I have namely examined such tentacles taken in the Kola fiord (The Russian biological station) and labelled Zoanthus sp., and they were tentacles of Cribrinopsis (PI. 3 fig. 7). The exterior aspect and the arrangement of the muscles are about the same in both species, but the size and the structure of the nematocysts are very different. I have often found such tom-off tentacles in Cribrinopsis from different locahties. i6o ACTINIARIA Habitat tentacles nematocysts spirocysts actinopharynx nematocysts numb mesenterial pairs er of ten- tacles verru- cae 20 + 20 64 5 40 80 + 41 82 + 20 + 20? about 80 ? 22 + 24 79 ? 20 + 21 — + — 78 — 20+21 71 + — — + — — + probably — + decamerous 26 + 29 90 + ? 20 + 2I 79 ? 79 — 72 + 7^ + ? 80 + — — + 20 + 20 — + — — + ~ ~ + 20+? 80 — 20 + 20 about 78 + ? |distribution of the reproduc- tive organ on the directives Sukkertoppen . . Claushavn Foster's islands . Corea strait . . . . Behriug's sea . . . Ritenbenk Bell Sound Egedesminde Treurenberg bay 25ofms.Torell (Locality ?) Duyn Point Fiskenses Ikamiut Greenland (without dis tinct locality) Bredefiord Greenland (without dis- tinct locality) St.47l(Romer & f St. 32I Schaudinn)^ GreetJand locality ? Faroe islands * Sukkertoppen Murman coast (only tentacles) Ora fiord (small spec.) Finmark Egedesminde 42— 60x2,5(3) u 43—60x2,5 41—55x2,5 41—53x2,5 46 — 62 X 2,5 55—67 X 2—2,5 46 65 X 2—2,5 38—50X2—2,5 ' 50—70 X 2 50 — 68 X 2 — 2,5 46 — 63X2 — 2,5 48 62 X 2 2,5 43—60X2.5—3 43—55 X 2.5 49 — 60x2 — 2,5 43—58 X 2 36—54 X 2—3 43—58x2,5 46—55 X 2 (2,5) 48 61 X2 2,5 48—55 X 2—2,5 38—52 X 2,5 46 60 X 2 2,5 55—67X2 31—43X2,5 39—55 X 2—2,5 43—62x2,5 22 x I — 1,5 — 53 X 2 — 2,5 fi 22 x 1,5 — 50x2 — 2,5 19x1,5 — 50x2,5 24 X 2 — 67 X 3 22 X 1,5 — 50 X 2 — 2,5 72 X 1,5 — 50x2 24 X 1,5—48x2,5 22X1,5— 43? X 2.5 19 X 1,5 — 46 X 2 — 2,5 22x1,5—53x2—2,5 42—53 X 3.5—4.5 ," 55—62 X 3,5 55—66X4—4,5 41—50X4—4,5 46—62 X 3,5 — 5 48—60 X 3,5 — 4,5 48—58 X 4—4,5 42—53 X 4—4,5 50—67x3,5 46—58x3,5—4.5 58—67 x 4,5—5 48 — 60 x 4.5 — 5 48—55x4,5 43—55x4—4,5 53—58x5 43—58 x 4—5 46 — 60 X 4 — 5 48—55 X 4,5 48—55 X 5 49—58 X 4,5 46—60 X 4,5—5 46—58 X 4,5 46—55x4—4,5 48—62x3.5—4.5 ?d:o $d:o (?d:o $d:o 'nx is retained, as the following tables clearly show. Urticina felina coriacea & tuberculata. Priaptis felinus, Linne 1761 p. 510. Actinia felina L., Linne 1766 — 68 p. 1088. Tealia felina I,., Fischer 1875 p. 1207/7). Urticina felina {!,■), Haddon i88g p. 298. Actinia coriacea Cuv., Rapp 1829 p. 51 PI. i figs. 3, 4, Sars 1835 p. 3 Danielsen & Koren 1856 p. 87. Cribrina coriacea Cuv., Ehrenberg 1834 p. 40. Cereus coriaceus Milne-Edwards 1857 p. 264. Tealia coriacea (Cuv.), Carlgren 1902 p. 43, Walton 1908 p. 219. Actinia {Isacmaea) papulosa. Urticina papulosa Ehrenberg 1834 P- 33- Cereus papillosus Milne-Edwards 1857 p. 264. Actinia tuberculata n. sp.. Cocks 1851. Tealia tuberculata Cocks, Gosse i860 p. 217, Cunningham 1890 p. 205 PI. 19. Actinia crassicornis Miill., Gosse 1853 p. 74, {Cribrina v. Tealia) Liitken 1861 p. 191. Mobius 1873 p 100. lycnz 1882 p. 171. Bunodes crassicornis (Miill.), Gosse 1855 p. 294, Meyer & Mobius 1862 p. 231, 1863 p. 174. Tealia crassicornis (Miill.), Gosse 1858 p. 417, i860 p. 209 PI. 4 fig. i. O. & R. Hertwig 1879 PI. 2 figs. 2, 6, 7, 9, 12, Andres 1883 p. 415 fig. 24, Mobius 1883 p. 12, G. Y. & A. F. Dixon 1889 p. 320 PI. 5 fig. 5, Leviusen 1893 p. 395, Mortensen 1897 p. 316, Grieg 1898 p. 6, Blegvad in Petersen 1914 p. 43. Urticina crassicornis Ehr.! Verrill 1869 p. 469 (p. p.), (Miill.) Carlgren 1S93 PI. i fig. 20 textfigs. 9 — 13 (p. p.), Appellof 1905 p. 83, 86, (Ehr.) Pax 1920 p. 7 figs. 3 — 6. ?(Miill.) Ehr. Mc. Murrich 1901 p. 28 fig. 2 PI. i fig. 6. PRhodactinia davisii Agas. Verrill 1864 p. 18 (p.p.). Tealia grenii n. sp. Wright-Perceval 1859 p. 122. Actinia holsatica n. sp. Mtiller 1806 p. 23 PI. 139. Compare further Andres 1883 and Carlgren 1893. Diagnosis: Compare above. Colour of coriacea verj^ variable. Column now crimson, now with green streaks and crimson flakes, now ochreous-coloured or olive-brown, now grayish. Warts gray or bluish-gray. The main colour of the tentacles is white or gray, shading off into bluish-gray or pale crimson. An opaque white band across the base of the tentacles and a broad crimson-coloured band in the middle, below and sometimes above outlined by a narrower band of opaque white colour. Sometimes these bands are indistinct. Oral disc grayish or 164 ACTINIARIA glaucous-olive, around the inner tentacles with radial bands, now white or yellowish-white, now ochreous- coloured; between the bands the oral disc is crimson-coloured. Mouth generally with crimson or red-brown tinges. Gonidial tubercles crimson-coloured. (Gosse, Carlgren). Dimensions: tubercidata in contracted state: breadth unto 9 cm, height unto about 6 cm, coriacea is smaller. Occurrence: Norway. Lofoten Saltstrommen 90 fms. (/) (Norw. N. Atl.-Exp.), Dronthjem fiord Skamsund 60 — 200 m (/) (Ostergren, Pettersson), Beian (Huitfeld- Kaas), Floro (c) (Sars), Vaagsfiord (teste Grieg), Bergen, Godosund (/) (Nordgaard), Bergen (/) (Appellof), Bergen Solsvig (Sars), Jaderen 100 fms. (Olsson), Flekkefiord 150 — 200 fms. (Fjorsvaag), Farsund. North Sea. Great Fisher Bank N. W. of Bergen 60 — 200 fms. (Swedish fishermen), W. N. W. of Bergen 80 — 170 fms. (Lambert), S. W. of Haugesund ' at Bergen 15 — 24 miles from land 100 — 170 fms. (Swedish fishermen), N.W. of Egersund 100 fms. (Swedish fishermen), Jydske Rev 50 — 200 fms. (Uddstrom, Nilsson and other fishermen). Faroe Isl. (c) (Miiller), Thorshavn (c). 64°27' N. I3°27' W. 150 m. Bottom temp. 4,5 (probably /) (M. Sars-Exp. 1902 St. 91). Skagerrak 140 m (Thor-Exp. 1903), Kosterfiord N. Hellso (c) (Aurivillius). Cattegat. Bohuslan Strommame, Gasoranna and other localities at a few fms. (c) (Carlgren and others), Bohuslan without distinct locality (B. Fries, Stuxberg), Zool. Station i sp. from deep water (/) (Carlgren), Laholm bay Kattvik 8 m (c) (Lonnberg); S.E. of Muldbjergene 12 m (teste Bleg- vad), E. of Munkegrund 40 m (teste Blegvad), V2 V4 nvles E.N.E. of Lillegrund (teste Blegvad). The Sound. HeUebak (c) (Jungersen), off Helsingborg 20 fms. (Gunhild-Exp. 1878), Landskrona (c) (Orsted), N. of Hven 25 m (teste Blegvad). Denmark. Livo Bredning (teste Blegvad), Thisted Bredning 11 — 12 m. (teste Blegvad), Limfiord (teste Mortensen), Samso (Liitken teste Levin- sen), -Isefiord Frederiksund (Feddersen teste Levins en), Adelvig (c) (Lundbeck), Odensefiord Hofmansgade (c) (S teens tr up, Liit ken), Little Belt, Strib & Faeno (c) (Liitken), Svendborg Sound (Steenstrup, Lutken teste Levinsen). Baltic Sea. Kieler Bucht, Biilk (teste Meyer & Mobius) Cadetrinne 15,5 fms. (teste Mobius), Travemiinde Bucht, Niendorf Haffkrug 2 — 9 fms. (teste Lenz), S. of Bomholm 8 — 9 fms. (/) (Mortensen 1891). Further distribution: British Islands, English Channel, Atlantic coast of France, Vendee, Charente-Inferieure; ? Atlantic coast of N. America to Cape Cod. ? West Coast of N. America. Puget Sound Port Townsend. (The North American Urticina requires closer examination. Whether the real Urticina ACTINIARIA 165 felina coriacea with large warts occurs there, seems a little doubtful to me. Besides crassicornis, we probably have to do with tuhcrcidata or lofotensis). Exterior aspect: The exterior of this form has before been described by various authors, also by myself (1893). It is not necessary to recapitulate the description here. Anatomical description. Several authors, also I myself (1893) have described the anatomy of this form. As however several facts can be added, concerning the structure of various organs, it may be practical to make these organs subject to a reexamination. Concerning the structure of the verrucae I have, after an examination of the maceration preparations, been able to determine the nature of "the pyriform cells", which Mc. Murrich (1889 p. 53) supposed to be "nerve ganghon cells", and on which he later (1911 p. 76) pronounced the opinion that they "may possibly be muscular in character." Alreadj^ 1899 p. ii^ I have, however, pointed out that the pyriform cells are granulous gland cells, "die in dem proximalen TheU des Ektoderms langgestreckt birnformig sind nach aussen dagegen einen sehr feinen Ausfiihrungsgang haben." A comparison between the ectoderm in the middle part of the verrucae, viz. the part, which in contraction is a little concave, and the ectoderm in the side-parts, with which the other ectoderm of the column agrees, shows, that the middle part is constructed in another way than the other parts of the column. The figures i, 2, PI. 4 show the cells occurring in the middle part after a treatment with the maceration hquid of Hertwig (osmium & acetic acid. Hertwig 1879). In the figure I PI. 4 the maceration is imperfect, in as much as the cells are still joined in the distal part, while their basal parts are separated. Already here we can see that the ectoderm cells consist of elongated support- ing cells and granulous gland cells, which is still more conspicuous as the cells are perfectly isolated (Fig. 2, PI. 4). The granulous gland cells are thus the pyriform cells. They are namely swollen near the basal part of the ectoderm, while the main part forms a long efferent duct, and recall in their appearance the gland cells of the pedal disc, though the latter are more irregular (Fig. 3, PI. 4) than the former. There is thus no doubt that the pyriform cells are gland cells. Macerative preparations of the ectoderm outside of the pecuhar verrucae, viz. on the rim of the concave part and between the verrucae, show the presence of supporting cells, of nematocysts, of mucus-ceUs (Fig. 4 a, PI. 4), and of granulous gland cells. These last cells, however, are of quite another structure than the gland cells of the verrucae. As we see from the figure 4 b (PI. 4) , they are shorter and broader in the distal part than in the filiform proximal part, which is devoid of granules, and a little coloured. The secretion of the pyriform cells probably is of small importance to the adhesion of foreign bodies, neither do the gland cells of the pedal disc play anj' essential part by the adhesion of the pedal disc. ^ Wassilief f (1908 p. gg) has proclaimed that in my papers of 1893 and of 1S99 I have made myself guilty of an inconsequence, concerning my statements of the structure of the verrucae. Concerning the nematocysts he seems to be right. In the main there are no nematocysts in the ectoderm of the verrucae, but where they are adjacent to the other ectoderm of the column, which contains nematocysts, glandcells etc., solitary nematocysts and also common gland cells may pass into the outermost part of the peculiar verruca, while the main part of the verruca contains no nematocysts. Hence ray different statement: sparse nematocysts and no such. Con- cerning the gland cells in the verrucae I have in my paper 1S93 not been able to decide the nature of the pyriform cells, wherefore I also 1893 declared that there were no gland cells in the verrucae. The statement of Wassilieff , that the verrucae of Cribrina japo- nica have the same structure as the other ectoderm of the column, is certaini)' due to the sections not having hit the middle part of the verrucae. On the other hand, he describes the verrucae of Anthopleura mc. murrichi in the same manner as I (1899 p. 11) have described them in Vrlicina and Condylactis cruenluta. The classification of the verrucae in "Saugwarzen" and "Klebwarzen" (Pax 1914 p. 360) does not hold good. Pax has evidently not observed my statement of iSgg. i66 ACTINIARIA Fig. 172 The structure of the sphincter varies from palmate to pinnate, and affords no good character neither of the species nor of the genus. The longitudinal muscles of the tentacles are mesogloeal, as already observed by O. and R. Hertwig 1879. They, however, show a certain variation, in as much as they are now ecto-mesogloeal now meso-ecto- dermal. It was therefore formerly supposed that the mesogloeal tentacle nmscles were characteristic of Urticina felina coriacea. In fact the variation is still greater, as I have in small, but sexually ripe specimens found a perfectly ectodermal longitudinal muscularity of the tentacles. I haveinthetextfigure 171 reproduced a transverse section of part of the tentacular muscles and the mesogloea of one of the below named specimens from Hellebsek, which certainly is a real U. felina coriacea. The specimen has namely well-developed verrucae, its sphincter is palmate, the mesenteries show the arrangement, characteristic of Urticina, and the nemato- cysts in the actinopha- rynx and tentacles agree with those of this species. For comparison I have in the textfigures 173, 174 reproduced transversal sections of two pieces of tentacles of an Urticina from Heligoland. On one piece we find a compara- tively thin mesogloeal la- mella outside of the ra- ther fine muscle meshes, the part of the mesogloea facing the ectoderm here and there displays distinct muscles. On the other piece the comparatively few meshes are found wholly within the mesogloea ; whether there are muscles to be found also on the ectodermal side, I will leave un- decided, as, upon all accounts, if present they are ver^^ weak. The two latter figures have been reproduced from the same section, which shows that the variation is very great at the same level of a tentacle. The longitudinal muscles of the tentacles of Urticina thus vary from ectodermal to ecto-mesogloeal, possibly to wholly mesogloeal. The radial muscles of the oral disc agree with the longitudinal muscles of the tentacles. I have before (1893) shown that they are ecto-mesogloeal or perhaps more correctly meso-ectodermal. In the textfigure 172 part of a transverse section through the oral disc of the above named specimens from Hellebaek has been reproduced. As we see, the radial muscles are ectodermal. Thus longitudinal muscles of the tentacles and the radial muscles of the oral disc vary from ecto- dermal, in smaller but sexually ripe specimens, to more or less mesogloeal, in middle-sized and large specimens. In other words, the folding of the ectodermal muscle lamella into the mesogloea, or tlie fusion of the peripheric Textfigs. 171 — 174. Urticina felina coriacea. Figs. 171, 173, 174 Transverse sections of a part of some tentacles. Fig. 172 Transverse section of a part of the oral disc. Figs. 171, 172 spec, from Hellebaek, figs. 173, 174 spec, from Helgoland. ACTINIARIA 167 mesogloeal off-shoots here evidently takes place rather late. Probably we here namely have to do with two different modes of development of the mesogloeal muscles. On the section, reproduced in the textfigure 174, the rather large, at last mesogloeal meshes may gradually have passed into the mesogloea, while on the section, reproduced in the textfigure 173, the peripheric end of the mesogloeal offshoots have fused with each other, the mesogloeal lamella, separating the meshes from the ectoderm, is namely often very thin (compare the figure of U. felina = crassicornis O. F. Mxill. Mc. Murrich 1911 PI. 2, fig. 4). Also the distribution of the reproductive organs varies. I have stated 1893 that the 10 first pairs of mesenteries of Urticina crassicornis (= U. felina coriacea) are sterile. I,ater on I have examined other specimens and found this statement confirmed, or that also the 10 pairs of the second order are completely or partly sterile. Mc. Murrich (1901 p. 34) declares that in U. crassicornis (a verrucous species from Puget Sound) the two first cycles of mesenteries are devoid of reproductive organs. In two more closely examined specimens fromHeUebsek (compare above), the size of which in contracted state was 0,7 cm in height and i cm in breadth, but still provided with well-developed reproductive organs (testes with spermatozoa), it appeared on sections that of the older mesenteries only 6 pairs were sterile. One specimen was provided with 40 pairs of mesenteries and thus, as to the number of the mesenteries, in the stage, reproduced by Faurot (1895 p. 139). In the proximal part of the actinopharynx there were, however, 6 pairs perfect; whether in the distal part some more mesenteries are perfect, I have not examined. Faurot has shown that the decamerism of Urticina is due to the fact that the development of the mesenteries in the ventro-lateral compartments is retarded. Thus in the dorso-lateral and the lateral compartments there is one cycle more than in the ventro- lateral compartment. The 10 first pairs consist of 6 pairs of the first cycle and of 4 of the second (in the dorso-lateral and lateral exocoels). The 10 following pairs, alternating with the former, are formed by 2 pairs of the second order (in the ventro-lateral exocoels) and 8 pairs of the third order (in the other exocoels). The 20 following pairs have arisen as 4 pairs of the third order (ventro-laterally) and 16 pairs of the fourth order. The arrangement of the reproductive organs of the specimens was as follows. The figures indicate the different cycles, if we issue from a species with the mesenteries originally arranged after the number of 6. The decam- erism of Urticina is namely, as above named, derived from a species with originally 6 pairs of mesenteries. The spaced out figures indicate the fertile mesenteries, dm : directive pairs. dm dm 14 3 424341434243413 2 313 2 31434243414342434 The arrangement of the mesenteries in the second specimen, having 43 pair, was the following. dm d"" 1 434524 3 41434243413234 132 3 41434243414342434 In this specimen two pairs of the fourth cycle (in the ventrolateral compartments) and one pair of the fifth (in a dorso-lateral compartment) are added. Here we find, that also the mesenteries of the third cycle in the ventro-lateral compartments, and 3 pairs of the fourth cycle in a primary lateral compartment, are provided with reproductive organs. If we compare those results with the former observations, we may conclude that the position of the reproductive organs varies with the age of the animal; in the youngest specimen (an examined specimen still i68 ACTINIARIA smaller than those mentioned above had no reproductive organs developed) the six first pairs are sterile, in older ones the lo first pairs (the first decade) are devoid of reproductive organs, and in large specimens the steriUty sets in with the 20 oldest pairs; in other words the generating region moves during the life- time of the animal to more and more younger mesenteries, simultaneously with the increase in the number of mesenteries. A similar, though less positive case I have observed in Allantactis parasitica, in which the mesenteries of the second cycle sometimes are sterile. Commonly the distribution of the repro- ductive organs in the Actiniaria is constant or almost so, especially the forms in which the first order of mesenteries is fertile; though it is possible that sometimes such a moving of the reproductive organs takes place. I especially think of such forms as Bolocera, in which the distribution of the reproductive organs varies. The size of the nematocysts is shown on the following table. Habitat length and breadth of the spec. Nematocysts of the tentacles the actinopharynx varieties Skagerrak (Thor) J ydske Rev Faroe Isl S. W. of Bergen . GuUmarfiord . . . . Helleba?k GuUmarfiord . . . . 6,5 cm 1 9,5 cm 5 6 4 6,5 4 4.5 i 2 2 0.7 I 0-4 0,4 24— 34x2— 2.5 ^(. 24 — 26 X 2 25 — 29 X 2 24 — 26 X 2 (21)24 — 29x2 (2,5) 17 — 22X1,5 almost 2 19 — 23x1,5 almost 2 16—23x1,5 74—85x5—6^4 72—82 X 5,5—6 (7) 67—79 X 5 60 — 79 X 5 70—74 X 5,5 45—60 X 5 43—55 X 4.5—5.5 49—56x4,5—5,5 probably tubcrculata probabh- tuberculata The specimens i and 6 were rather well expanded, the others much contracted. The size of the spiro- cysts was in the spec, i, 24 X 1,5 — 50 X 2,5 ;«, in the spec. 3, 22 X i — 46 X 2 //, in the spec. 7, 14 X i — 24 X2 fi. The nematocysts of the column were in the column of the specimen i, 19 — 26 x(i,5) — 2 fi, in that of the specimen 6, 12 — 19 x 1,5 — 2 /i. In the column I have also found scattered spirocysts. Smaller nematocysts than the above named I have obser\'ed in the column and in the tentacles, but they are very rare (compare lofotensis and crassicornis) . Urticina felina lofotensis. Madoniactis lofotensis n. sp. Danielssen 1890 p. 47 PI. i fig. 5 (p. p ). Urticina crassicornis i.laevis Carlgren -in Appellof 1900 p. 4. Tealia lofotensis (Dan.) Carlgren 1902 p. 42. Rhodactinia crassicornis (Miill.) Walton 1908 p. 218, Arndt 1912 p. 124. PRhodactinia davisii Agas. Verrill 1864 p. 18 (p. p.). PBolocera eques n. sp. Gosse i860 p. 351 PI. 9 fig. 6. P — — Gos. Norman 1868 p. 318, Stephenson 1918 b p. 112. Diagnosis: Compare p. 162. Colour: Column and pedal disc yellowish-red with dark-red partly stripes and partly patches. Tentacles transparent, pale yellowish-red with i to 2 broad, red annuli besides the one at the base. Oral disc rose-coloured with fine, red folds, issuing from a red annulus round the mouth and extending towards the ACTINIARIA 169 tentacles, where they form a bright-red annulus {Madoniactis Danielssen). Column dirty -yellow, brownish or brown-red, sometimes with red or reddish, longitudinal spots. Tentacles sometimes uncoloured, sometimes dirty-yellow, brownish or brown-red, frequently with more or less distinct, paler or darker transverse bands, sometimes th^ tentacles are crimson-coloured [U. crassicornis f. laevis Appellof). Compare also Walton 1908 p. 218 — 219. Dimensions in contracted state unto about 5,5 cm broad and 2,3 cm high. Occurrence, compare U. felina coriacea. Exterior aspect. The type-specimen, dredged by Danielssen, was much contracted in oral- aboral direction. Therefore I cannot decide, whether the column is furnished with small verrucae or not, but Danielssen declares that there are such. Besides, the description of the spe- cies, givenby Danielssen, has beencom- pilated also frona Metridium senile {dian- thus) (compare C a rig r en 1902 p. 42). Appellof 's specimens (Appellof 1900 p. 4) as also those collected by Nord- gaard.are provided with small verrucae. In the not sexually ripe specimen, dred- ged by Mortensen S. of Bornholm, I cannot see any verrucae by aid of a magnifier, but on the sections there are scattered excavations in the column, in- dicating the presence of small verrucae. y Therefore I think that this specimen is forma lofotensis and not crassicornis. Anatomical description: Con- cerning the anatomy of tins form I have not much to say. Small specimens agree with such of U. felina coriacea, in as much as the longitudinal muscles of the tentacles a;nd the radial muscles of the oral disc are ectodermal (textfig. 176, 177). The sphincter of the Bomholm-specimen (fig. 175) differs somewhat from the typical appearance of the sphincter of Urticina. The size of the nematocysts {n) and spirocysts [sf) of some specimens I have given below. Fig- 175 Fig. 177 Textfigs. 175 — 177. Urticina felina lofotensis from Bornholm. Transverse sections of the sphincter (fig. 175) of a part of the oral disc (fig. 176) and of a part of a tentacle (fig. 177). Habitat length and breadth of the specimens column n tentacles n sp actinopharynx « Saltstrommen (type) .... Bergen (Appellof) .... Bornholm Drontheim fiord 1.5 cm -.5 0.3 ^,5 5 cm 5 2,2x1,5 5.5 20 — 23 X almost 2 u 22 — 26 X about 2 17 — 22 X almost 2 19 — 24 X almost 2 24 — 29 X 2 — 2,5 {.l 26 31 X 2 — 2,5 22 — 26 X almost 2 24 29 X 2 17x1 — 48X2,5H 5 — 26 X 2 62 — 77 X 5 — 6 H 60—80 X 5 — 5,5 43—55 X 5 70—82x6(7) The Ingolf-Expedi[ioD. V. 9. ,_^ ACTINIARIA 170 . In the column of all species I have found also smaller nematocysts, 7 — 12 X 1,5 //• The nematocysts of the column are sparse, especially the smaller ones. Scattered spirocysts are also obser\^ed in the column. In the tentacles I have sometimes observed smaller nematocysts of about the same size as those of U. felina crassicornis. Urticina felina crassicornis. Actinia crassicornis n. sp. Miiller 1776 p. 231, Fabricius 1780 p. 348, 1797 p. 52, Liitken 1875 p. 186. Urticina crassicornis Ehr. ! Verrill 1868 p. 469, 1885 p. 534 (p. p.), Miill. Carlgren 1893 p. 58 (p. p.), 1901 p. 470 fig. 2 a, b. Rhodactinia crassicornis Miill. , Carlgren 1902 p. 40 figs. 4, 5 (p. p.). — davisii n. sp. Agassiz 1847 p. 677. — — Agas. Verrill 1863 p. 57, 1864 p. 18 PI. i fig. 9 (p. p.), Agassiz 1865, 1871 p. 13 fig. 10, Packard 1865 p. 263, ?Pax 1915. Urticina {Rhodactinia, Tealia) davisii Agas. Carlgreni9i6p.i. Tealia davisii Agas. Breitfuss 1904 p. 6, Carlgren 1905 p. 511 fig. i. — crassicornis (Miill.) Parker 1900 p. 752 (p. p.). Tealia sp.? Carlgren 1893 b p. 213. Leiotealia spetsbergensis n. sp. Kwietniewski 1896 p. 134 (p. p.). Actinia obtruncata n. sp. Stimpson 1853 p. 7. Actinia {l)felina I,. Milne-Edwards 1857 p. 242. Urticina felina ly. Marenzeller 1877 p. 23, Stuxberg 1886 p. 163, 186, Mc. Murrich 1911 p. 65 PI. r, 2, 3 fig. I. Bolocera tuediae Johns. Aurivillius 1886 p. 52. Diagnosis: Compare p. 162. Colour: Column uniformly red or else with a ground colour of pale red or yellowish, upon which were closely set, irregular blotches and streaks of carmine, so that the general effect was that of a brilliant carmine. Tentacles of a beautiful translucent pink, sometimes uniform throughout, in other cases deepening somewhat in tone at the tips and also at about the middle, where an indistinct band occurred. At the base each tentacle was surrounded by a pair of deeper pink streaks, which were prolonged some distance upon the disc. Oral disc pink in colour, peristome dotted and streaked with crimson, gonidial angles flesh-coloured (Mc. Murrich). Column red, oral disc pale, tentacles chestnut-brown with pale apex. Column orange-red (spec, from Recherche bay). Pale red or reddish yellow (Romer & Schaudinn St. 46). Dimensions: The largest examined specimens (from the Kara Sea) was about 3,5 cm high and 8 cm broad at the base. Occurrence: North America. New Foundland 46°5' N. 5i°44' W., 45°3' N. 5i°49' W. 56 fms. 45°53' N. 5i°56' W., 46%' N. 52°3' W. 46—50 fms. (Ingegerd & Gladan-Exp.). George's Bank42°23'N.6o°23'W. 141 fms. (Albatross- Exp. 1883). Eastport, Maine. ACTINIARIA J71 West-Greenland. Upernivik (Kraul 1909); Sakrak Vaigattet (Traustedt 1892). Discofiord Middlefiord 100 — 200 fms. (Ingegerd & Gladan-Exp.). 69°29'N. 55°26' W. 116 fms. (Tjalfe-Exp. St. 179 1908). Jacobs- havn (Ryder 1892). Claushavn 20 fms. Fortune bay 12 — 25 fms. (Oberg 1870). Nordre Stremfiord 325 — 330 m. Bottom temp. — 0,1, Salinity ■}y°7 (temp. +3) (Nordmann 1911 St. 3 a). Store Hellefiskebanke (Holm 1887). Holstensborg (Ingegerd & Gladan-Exp. 1871, Holm). Godthaab 100 fms. (Ammondsen). Bredefiord 24 — 100 m (Rink-Exp. 1912). Kvanefiord 290 — 400 m, 34 — 40 m (Rink-Exp. 1912 St. 12, 13). 69°46' N. 5i°22' W. 250 fms. (Tjalfe-Exp. 1908 2'/,). East-Greenland. The sound between Maatten and Renskaer 25 — 30 fms. (Danmark- Exp. 1898). Angmasalik (Soren Nielsen 1901), lyocality? (Ryder 1892 l«/3). Jan Mayen. 70 — 90 fms. (Michael Sars-Exp. igoo) ; 100 m. Bottom temperature — 0,4 (Michael Sars-Exp. 1900 St. 25); 55 fms. (Soren Jensen). Iceland. Berufiord 63°i7',5 N. I7°39' W. 87 fms. (Beskytteren, Johansen 1905). Vestmanno (Ssemundsson). 64^27' N. I3°27' W. West-Spitzbergen. I,ow Isl. 16 fms. (Sw. Spitzberg-Exp. 1861) ; So° N. i7°5' E. 40 fms. (Sw. Spitzberg-Exp. 1861). Treurenberg bay 6 — 30 fms. (Sw. Spitzberg-Exp. 1861). Danish Gat 20 — 30 m (Wulff 1899). King's bay 200 fms. (Sw. Spitzberg-Exp. 1861), Bell Sound 30 — 40 fms. (Torell) 3 — 35 fms. (Sw. Spitzberg-Exp. 1873). Icefiord: Save harbour 20 — 40 fms. (Malmgren 1864). Entrance to Dick- son bay 14 — 44 m (Sw. Spitzberg-Exp. 1908). Recherche bay 20 — 30 fms. (Klinckowstrom), o — 20 m (Sw. Spitzberg-Exp. 1898), off Fox's glacier 75 — 90 m (Sw. Spitzberg-Exp. 1898), 77°3o'N. I4°36'E. 30— 40 m (Sw. Spitzberg-Exp. 1898). East-Spitzbergen. Foster Isl. 40 fms. (Sw. Spitzberg-Exp. 1861). Waygat Isl. (Sw. Spitzberg-Exp. 1861). Bismarck strait 78°58'5 N. 20°35' E. 35 m. Unicorn bay 78°4o' N. 2i°3i' E. 60 m (Romer & Schaudinn St. 45, 46). Whales point 20 — 30 fms. (Malmgren 1864). Devee Bay 12 — 15 fms. (Kiikenthal & Walter). Entrance to Devee bay 77''23'N. 2i°2o' E. 28 m (Romer & Schaudinn St. 8). Wolter Thymen strait 30 — 40 fms. (Malmgren 1864), 78°i4' N. 2i°45' E. (Romer & Schaudinn St. 47). Ryk-Yse Isl. 77^49' N. 25°I2' E. 60 — 80 m (Romer & Schaudinn St. 49). King Charles Land between Jena and Abel Islands 40 m (Romer & Schau- dinn St. 32). 22* ^„^ ACTINIARIA 172 North Atlantic. ' 64°53' N. 10° E. 600 m. Bottom temp. — 0,69° (Michael Sars-Exp. 1910 St. 10). Norway. Finmark. Kvaenangen (Aurivillius). Ogsliord 100 m. Bottom temp. 2,1° (Nordgaard). Kvalsund 20 fms. (Sw. Spitzberg-Exp. 1861). Grot- sund 70 fms, (Goes & Malmgren). Grotsund Finkroken low- water stand (Sw. Spitzberg-Exp. 1861). Ulfsfiord. Kjosen low-water stand (Sw. Spitz- berg-Exp. 1861). Vardo. Kola peninsula. lyadigino. 66°36'5 N. 4i°23' E. 65 m. Kildin Sound 69°2i' N. 34°5' E. 86 m (Romer & Schaudinn St. 56, 59). W. of Kolgujew 69°i4' N. 46°39'30 E. 62 m (Andrei Perwoswanny-Exp.). Chewanna 30 fms. (Sandeberg 1877). Kara Sea. 49 fms. (Dijmphna-Exp.). Arctic Sea of Siberia. 69°32' N. 177° 41' E. (Vega-Exp.). 67^7' N. i73°24' W. 9—15 fms. (Vega-Exp.). 2 miles N. of the winter-harbour of the Vega 12 fms. N. N. W. of the winter-harbour of the Vega 12 fms. (Vega-Exp.). Behring's Sea. Behring Isl. 65—75 fms. (Vega-Exp.) ; 65°i4' N. i68°35' W. 29 fms. (Vega-Exp.); 62=39' N. I77°5' W. 55 fms. (Vega-Exp.) Further distribution: Arctic America to Cape Cod (teste Verrill. This statement needs con- firmation). George's and Brown's Banks (teste Verrill). Passammoqvoddy Bay (teste Mc. Murrich). Grand Menan (teste Stimpson). Labrador (teste Packard). Murman Sea 79°5' N. 6i°23' E. 203 m (teste Maren- zeller)? Olenja Guba. ?Pala Guba (teste Pax). This form, "the true Urticina crassicoynis of the north" (Verrill 1868 p. 470) has undoubtedly been described by Mc. Murrich 1911. I have not much to add to the description given by Mc. Murrich. The column of all specimens was smooth without verrucae. Only in one specimen (from Recherche Bay) the column was provided with spots, recalling contracted ^•errucae. A nearer examination of these formations, however, showed that they were not verrucae but probably only pigment spots. L,ike Mc. Murrich I have found that the longitudinal muscles of the tentacles are sometimes ectodermal. In a small specimen, exam- ined by myself, the longitudinal muscles of the tentacles, as well as the radial muscles of the oral disc, were ectodermal. The greatest number of the tentacles was about 160, that of the pairs of mesenteries 83 (in a specimen from the Tjalfe-Expedition). The number of mesenteries was sometimes different in both sides of the directive plane (compare the table). Concerning the distribution of the reproductive organs I cannot decide whether the same mesenteries as in U. felina coriacea are fertile. In a specimen from Greenland there are probably 10 primary pairs of mesenteries sterile. Commonly the 20 first pairs are sterile, in the specimen with 83 pairs of mesenteries the reproductive organs were probably present only on the mesenteries of the fourth cycle (compare Mc. Murrich 1911 p. y^)- Thus it is probable that the generating region moves during the lifetime of the animal as in U. felina coriacea. In many specimens there were numerous embryos in the coelenteric cavity. ACTINIARIA 173 The following table shows the size of the spirocysts and nematocysts in a series of specimens, and also some other statements. Habitat Tentacles neinatocj-sts spirocysts Actinopharynx nematocysts Pairs of mesen- teries Niunber of tentacles Distribution of the reproductive organs Embr>'os in the coelen- teric cavity Eastport 24—29X2 H 24—31X2-2,5 24—28X2 26—31X2(2,5) 26 — 29X2 26— 29(34) X 2 24—26x2,5 26 — 31X2 22—29x2-2,5 22 26X2,5 17— 22X1.5 22-29(3l)X2-2,5 24—29X2 26—29X2-2,5 22—26X2,5 27—31X2 24—31X2-2,5 22—24X2 27—34X2 24—29X2 27—31X2 24—29X2 29—31X2,5 27—33X2,5 26— 34X(2)2,5 22—29x2 —36X2,5 24—29x2-2,5 24—31x2.5 19— 25x1.5-2 24—26x2 12— I7X1 H 12—14x1 I4XI I7XI.5 12— I4X1 14 — I7XI.5 to 55X2.5 fi 22X1—48X2 19X1.5— 53X2.5 —55X2.5 22X1,5—43X2.5 22X1—53X2.5 —43X2,5 22X1—48X2,5 —46X2 24X1.5—60X2-2,5 24X1,5—58X2-2,5 —65X2,5 —41X2,5 1 65—74X5 t^ 58-84X5 60—77 72—84X6-7 66—82X5 62—72X5-5,5 50—65X5 60 — 72X5 53—65X5 53—67X5-5,5 53—77X5 43—48X4-4.5 60 — 72X5 65—79X5 67—79X5 62—70X5-5.5 55—67X5-5.5 65—73X5 62—77X5-6 60—70X4.5-5 79—86X6 55—70X4,5-5.5 65—82X4.5-5.5 60—70X5-6 65—84X5-5.5 67—84X4.5-5 67—82X4.5-5 58—72X5 60—72X5 77—91X5.6 58—70X5 65—74X4.5-5.5 50—60X4.5-5 60—72X5 67—77X5-6 20XZ2 20? 40X43 36X? 20X18 20XZI 40X? 42X? 40X? 40X40 38 no /§io? primary \ sterUe f DO reprod. org. ^_ (small spec.) ("probably only on 'nx 58 — 67 X 5 /i. The spirocysts of the tentacles variated from 22 X i — 1,5 // to 48 X 2,5 fi. The longitudinal muscles of the tentacles and the radial muscles of the oral disc were of the same appearance as in Urticina. The sphincter was palmate (without a distinct main lamella). The pairs of me- senteries were 10 + 10 + 16 = 36. Among the pairs of the last cycle two on each side of the directive plane were not developed. On one side the pairs i and 9 were wanting, on the other the pairs 8 and 9. In the lower part of the actinopharynx 10 pairs were perfect, more distally 20 pairs ; the mesenteries of the last cycle almost reached the actinopharynx. In the coelenteric cavity there were numerous embryos. The mesenteries contained numerous small eggs and such were present also on the mesenteries of the first and second cycles, which I have verified also on sections. The distribution of the reproductive organs thus agrees with that in Cribrinopsis and Cribrina, but not with that in Urticina. In this last genus the first 10, or in very large specimens the 20 oldest pairs namely commonly are sterile; in small specimens of U. felina coriacca I have found only the six first pairs to be without reproductive organs (compare Urticina felina coriacca). As the specimen was comparatively large, I think that it is difficult to consider it as a pure Urticina. An Urticina of the same size as our specimen has namely at least the 10 first pairs of mesenteries sterile. It is true that in certain genera, as in Urticina, a displacement in the appearance of the reproductive organs takes place, so that with the increasing age of the animal a cycle of mesenteries, which was fertile in young individuals, becomes sterile in older ones, in other words, the reproductive organs appear in older individuals in a later cycle than in younger ones, but I have never observed that a species beginning by developing the reproductive organs on the mesenteries of the first cycle afterwards loses this capacity, so that in a later reproductive period the fertility appears first on the mesenteries of the second cycle. I also think that a hybridisation between Urticina and Cribrina or Cribinopsis may be admitted, as the species occur together (compare p. 156). Genus Epiactis Verr. Diagnosis: Cribrinidae with smooth column, without warts, acrorhagi and pseudoacrorhagi. Column with (or without?) a cuticle. Tentacles simple, cylindrical or conical, short. Longitudinal muscles of the ten- tacles and radial muscles of the oral disc ectodermal. Mesenteries hexamerously arranged (always?). Repro- ductive organs found on the mesenteries of the first cycle and on the other stronger mesenteries. The diagnosis given by Stephenson (i9i8ap.24) of the genus is too comprehensive, as, according to that formation, the genus Isotealia, as well as Urticina felina crassicornis, and possibly certain specimens of Cribrinopsis similis, may be arranged into the genus. Therefore I have set up a new, somewhat more distinct diagnosis, by which also the genus Pseudophellia Verr. may be included (compare p. 145 — 146). Concerning ACTINIARIA 175 the species placed by Stephenson with Epiactis, the systematic position of some of them is questionable, and E. fecunda, dubia, badia and nymphaea are only provisionally to be referred to Epiactis. According to me, E. (Leiotealia) spetsbergensis must be dropped, as this species includes at least two, possibly a few more, species, belonging to different genera. I have before put forth, that L. spetsbergensis perhaps for the greater part is an Urticina felina crassicornis. Sections through the tentacles of some specimens and a closer examin- ation of part of a specimen clearly show that we have to do with this species. The longitudinal muscles of the tentacles were namely principally mesogloeal, the distal end of the primary folds are fused together, so that a thin band of mesogloea is formed next to the ectoderm (the sections recall the figure 4 PI. 2, given by Mc. Murrich 1911). The nematocysts also agree with those of Urticina. The description, given by Kwiet- niewski, of a specimen — or maybe compiled from several specimens — indicates that the species is hetero- geneous, which I am able to confirm after having examined another specimen. This specimen possibly may be a Cribrina spetsbergensis, though the sucking warts seem to be absent (compare this species p. 155). I have before (1901 p. 43) suggested, that Leiotealia might be identical with Epiactis{?) fecunda — an opinion, which I based principally on the presence of a broodroom in a specimen of Kwietniewski's species, and on the absence of sucking warts. This suggestion however, requires, confirmation. On aU accounts, Kwiet- niewski's species contains at least two species, belonging to two different genera. Under such circumstances I prefer to abolish Leiotealia spetsbergensis. Among the Arctic Cribrinids I have found 4 species: Epiactis marsupialis Carlgr., E. arctica (Verr.), E. nordmanni n. sp. and E. incerta n. sj^. Epiactis marsupialis Carlgr. Epiactis marsupialis n. sp. Carlgren 1901 p. 482. Diagnosis: Column in contracted state generally conical, the height often twice the diameter of the body. Column with a shghtly developed cuticle; with distinct fossa. Sphincter generally of palmate type, strong. Ten- tacles conical, not or slightly longitudinally furrowed, in number to about 48 (6+6 + 12 + 24). Gonidial tubercles distinct. Actinopharynx long with about 24 longitudinal furrows and two well developed siphonoglyphes with rather well developed aboral prolongations. Mesenteries in three cycles (6 + 6 + 12 pairs), often more numerous than the tentacles, most of them perfect. Longitudinal muscles of the mesenteries well developed, broad. Parieto-basilar muscles very strong, reaching at most to the spliincter. Basilar muscles rather strong. Oral and sometimes marginal stomata present. Dioecious. 6 symmetrically placed pairs of the last cycle smaller than the others of the same cycle, without reproductive organs and mostly without filaments. The embryos develop in excavated pits on the outside of the aboral part of the column. Nematocysts in the ecto- derm of the column 22—32x2,5—3 fi, in the tentacles 18—26 X about 2 (1,5—2,5) n, in the actinopharynx 24 — 34(35) X 3 — 4,5 //. Spirocysts of the tentacles from (14) 17 X i — 31 X 2,5 /i. Colour in alcohol: Tentacles pale rose-red (i spec). The ectoderm of the column was brownish. Dimensions: The strongly contracted, in 1901 reproduced specimen, furnished with brood-pits, hada length of 1,8 cm, its largest breadth was 2,2 cm. Two other specimens were 3 cm resp. 1,4 long and 1,7 cm resp. 0,7 cm broad. 176 ACTINIARIA Occurrence: Arctic sea of Sibiria. 20° E. off Cape Jakan 12 fms. Sand and clay with stones (Vega-Exp.), 67°7' N. I73°24' W. 9 — 15 fms. mud and stones (Vega-Exp.), 2 miles N. of the winter station of the Vega 12 fms. sand (Vega-Exp.). Exterior aspect. The column was in contracted state generally conical, its length was often twice its breadth; the single specimen with extended tentacles was elongated, cylindrical. The pedal disc was as a rule a little involved and radially sulcated. The column was quite smooth in some expanded specimens, in others furnished with longitudinal and transversal ridges, and devoid of sucking warts, acrorhagi and pseudoacrorhagi. Its ectoderm is furnished with a weak cuticle, sometimes a little incrusted, and which seems easily deciduous (compare below). In three specimens (from Cape Jakan) there are brood-rooms devel- oped in the lower part of the column (compare Carlgren 1901), in the other specimens, among which there were some females, no brood-rooms appear. The fossa is distinct. The tentacles were short, strongly contracted and conical, about as long as broad, in one specimen more elongated, the outer tentacles a little shorter than the inner ones. Their surface was in preserved state smooth or weakly sulcated. They were hexamer- ously arranged, and the number in the examined species variates between 35 and 47 (35, 36, 41, 41, 43, 43, 44, 45, 47). The number of the tentacles was, as a rule, smaller than that of the mesenteries, in other words, the mesenteries grow forth from below upwards. The actinopharynx was long and furnished with about 24 longitudinal furrows and ridges. The 2 symmetrically placed siphonoglyphes were broad, in the upper part with 2 distinct gonidial tubercles, aborally a little prolongated. Anatomical description. The ectoderm of the column is high and contains numerous nemato- cysts like that of the tentacles and the actinopharynx. The nematocysts of the column are longer and a little broader than those of the tentacles, as the following table shows. column nematocysts tentacles nematocysts spirocysts actinopharynx nematocysts Sp. I - 2 - 3 - 4 - 5 - 6 - 7 - 8, - 9 - lo, from Cape Jakan 67°2' N. the winter station of Veea . 24— 31x2.5— 3 n 26—31x2,5—3 24—31x2,5 26 — 32 X 2,5 22 — 29 X2,5 ig — 22 X 2(2,5) !■' 22 — 26 X 2 18 24 X (1,5) 2 19—24X2—2,5 20 — 23 X 2 19 23 X2 19 — 24 X 1,5 — 2 19 — 25x1,5—2 19 22 X 1,5 {17)19 22 X 1,5 2 14 X I 26 X 2 H 17 X I — 29x2 17 X I — 27x2 19 X I 31 X2 — 26 X2 I7X1 29x2,5 I7X1 28X2,5 26—34 X .3—3.5 ^' 26—34 X 3—3.5 26—34 X 3—3.5 24—31x3,5—4,5 26—34 X 3—3.5 24— 34 x (2, 5)— 3,5 25—32 X 3—3.5 26—35 X 3—3.5 The homogeneous gland-cells of the column are very numerous, the granulous gland-cells fewer. The ectoderm of the column is furnished with a weak, easily deciduous cuticle. In some specimens it is lost, in the type-specimens there were fragment of a cuticle incrusted with foreign bodies; the cuticle appears most distinctly in the brood-rooms, from where it was not easily rubbed off. The mesogloea is rather thick and contains small protoplasma-poor cells. The endodermal circular muscles were very well-developed and the folds of the muscle layer ramificated. The sphincter was strong, of palmate type; in one examined ACTINIARIA 177 Textfig. 178. Epiactis marsupialis. Transverse section of sphincter. specimen the sphincter was proximally furnished with a main lamella which, however, soon became branched (textfig. 178, transverse section of the sphincter), in another specimen there was no main lamella in the sphinc- ter. The longitudinal muscles of the tentacles and the radial muscles of the oral disc are ectodermal, but the folds are rather low and only take up a small part of the height of the ectoderm. The folds are arranged like palisades, and at the insertions of the mesenteries on the oral disc con- siderably weaker and not as closely packed as in the middle parts. The ectoderm of the actinopharynx is very high in the ridges, in the furrows considerably lower. The mesenteries were in 5 examined specimens 48 (6 + 6 + 12 pairs). The pairs of the third cycle were un- equally developed. 6 pairs were strong, perfect and had well- developed reproductive organs and filaments, the other 6 pairs were weak, imperfect, in certain cases not reaching to the tentacular region, were devoid of reproductive organs and generally also of filaments. The six weaker pairs were in all specimens likewise arranged. If we use numbers to designate the different cycles of mesen- teries and begin with the one directive pair {dm) , the weaker pairs (designated by spaced out figures) were grouped in the following manner: dm dm 132313231323132313231323 In the largest specimen (with 47 tentacles) the weaker pairs of the third cycle were in the distal part furnished witli small filaments. Therefore it is possible that these mesenteries in still older specimens obtain longer filaments and perhaps also reproductive organs. All the stronger mesenteries were perfect. The me- senteries of the first cycle were coalesced with the actinopharynx to a larger extent than the mesenteries of the second order, the mesenteries of the third cycle were the least expanded on the actinopharynx. The longitudinal muscles form rather strong pennons with folds of about equal height. The parieto-basilar muscles were very broad in the proximal part and almost reach the sphincter. Oral stomata and sometimes marginal stomata were present, probably the latter are not permanent. The species is dioecious. All the stronger mesenteries are fertile. The ova are very large and rich in yolk. Of 9 examined specimens 3 were males and 6 females, 3 of the latter were furnished with brood-rooms. Epiactis arctica (Verr.). PI. 3, Figs. 8 — 10. PI. 4, Fig. 9. Phellia arctica n. sp. Verrill 1868 p. 328. 1868 p. 490. Andres 1883 p. 342. Pseudophellia arctica Verr. Verrill 1899 p. 376 textfig. 34. Diagnosis: Column elongated, covered with a well-developed but easily deciduous cuticle, and sprinkled with spots of special structure. Fossa distinct. Sphincter of palmate or palmate-pinnate type. Tentacles con- ical, not or slightly longitudinally furrowed, in numbers from 31 — 38 (6+6 + 12+ an imperfect 4th cycle). Gonidial tubercles distinct. Actinopharynx long with at least 24 longitudinal ridges and two well-developed The Ingolf-Expedilion. V. 9. 23 g ACTINIARIA siphonoglyphes with no aboral prolongations or with short ones. Mesenteries in those cycles (6 + 6 + 12 pairs) more numerous than the tentacles. Longitudinal muscle-pennons rather strong, broad. Parieto- basilar muscles very strong almost reaching the sphincter. Oral stomata but no marginal stomata. Dioecious. 6 symmetrically placed pairs of the mesenteries of the last cycle without filaments and reproductive organs. The embryos develop in excavated pits on the outside of the aboral part of the column. Nematocysts in the ectoderm of the column 29 — 37 X 2,5 — 3 fi, in the tentacles 24 — 30x2 — 2,5 //, in the actinopharynx (26)29 — 36 X 3 — 3,5 fx. Spirocysts of the tentacles 19 X i /i to 34 x 2,5 [i. Colour in alcohol: In a specimen the ectoderm of the column was dark brown especially in the distal part, and sprinkled with small white spots, Another specimen was more light brown, and a third in the distal part dark brown (in the proximal part the ectoderm was lost). The ectoderm of the column in the other specimens was uncoloured, here and there fragments of darker parts (cuticle?) were however present. Dimensions: A specimen, the column of which was much expanded, measured in height and breadth 3 cm. The largest specimen with involved tentacles and of a cylindrical-conical appearance was 3,4 cm long and 2 cm broad. The smallest specimen with visible tentacles was 2,1 cm long and 0,9 cm broad. Occurrence: 64°53' N. io°o' W. 630 m. Temp, at 600 m — 0,69 (Michael Sars-Exp. 1900). Arctic ocean north of Behring's strait 30 fms. (North Pac. expl.-Exp. — teste Verrill). Exterior aspect. Of the 10 specimens three were comparatively slightly contracted. Their column was cylindrical and their tentacles unfolded. P'our specimens were strongly expanded, their breadth and height about equal, the form of the others was Hke a drawn-out cone. The pedal disc was well-developed. The column was in the contracted specimen often a little longitudinally wrinkled. In a specimen, the colour of which was the best preserved, there were small, light, irregularly scattered spots, the largest spots appeared in the distal part, though also there they were almost inconspicuous to the naked eye; the smallest spots, scattered between the larger, and especially very numerous in the lower part of the column, were only conspicuous under strong magnifying powers. Traces of such spots were present also in another specimen. Some of the others show fragments of a thick cuticle (compare below) . Near the base of an expanded specimen there were several large circular spots reaching those I have observed in a specimen of E. marsupialis. In this species the spots were certainly marks of embryos, having evidently passed some time upon the parent after emigrating from their brood-rooms. From this I conclude that also this specimen of E. arctica has been fur- nished with brood-rooms. The fossa \yas distinct. The tentacles were conically drawn out, between 31 and 38 in number, hexamerously arranged, the last cycle was imperfect. Commonly they were smooth, sometimes a little longitudinally sulcated. The number of the tentacles was smaller than that of the mesenteries. The actinopharynx was long and furnished with at least 24 longitudinal ridges, sometimes more. The two sym- metrically placed siphonoglyphes show distinct gonidial tubercles, I am not able to find any perspicuous aboral prolongations. Anatomical description: The ectoderm of the column is high and contains very numerous nematocysts, which are longer than those of the actinopharynx. Their size variates between29 — 37 X 2,5-3 ,"• I" a specimen I found a capsule, 43 x 4,5 « in size. The above named small spots on the column of the best preserved specimen display another structure than the other parts of the body-wall. They are built up mainly of support- ACTINIARIA 179 ing cells (PI. 4 fig. 9), here and there a granulous gland cell was observed; on the other hand, there were no nematocysts, excepting in the rim of the spots, where they are, however, very rare. In the other part of the columnar ectoderm, the nematocysts, as well as the gland cells, were numerous. Of the gland cells some, the fewer, were more homogeneous, the others, the more numerous, contained a multitude of small brownish granulae. Whether the latter, which often reach a considerable size, are gland-cells of the same kind as the former, but in a differ- ent state of secretion, I cannot with certainty decide. Possibly the circumstance that I have not observed any such in the unpigmented specimens, speaks in favour of this suggestion, though I hardly believe tliis to be the case. In the unpigmented specimens the homogeneous gland-ceUs were, however, numerous, but the ectoderm of these specimens was not as well preserved as in the specimens with spots. As above mentioned, there were in some specimens frag- ments of a cuticle which is evidently easily deciduous. The cuticle seems to be very thick but incompact and cracked, and not of typical appearance. The me- sogloea of the column is thick and contains rather sparse protoplasma-poor cells. The endodermal circular muscles are ver>' well developed and form high, delicate, ramificated folds; in the region of the sphincter the muscle layer is weaker. The sphincter is strong and of a somewhat variable type. In a specimen it was on transverse sections round and distinctly palmate without a main lamella, and with a tendency (on some sections) to form meshes, in two other specimens it was compressed and of variable structure in different sections of the same spec- imen, now there was no distinct main lamella but rather several longitudinal la- mellae in the middle of the sphincter, now these latter were fusing in the middle part, or finally the sphincter was almost palmate. If a main lamella was pres- ent, it was always more weakly developed at the base than in the middle part (textfig. 179 from the specimen with spots). The ectoderm of the tentacles was very high with numerous nematocysts 24 — 30 X 2 (2,5) n and numerous spiro- Cysts, 19 X I /i to 34 X 2,5 n in size. The longitudinal muscles of the tentacles Transverse section of sphincter ■' ^ ' '^^ ' ^ (fig. 179) and of part of a ten- (textfig. 180 transverse section of a part of tentacle from Michael Sars- tacle (fig. 180). Exp. St. 10) were ectodermal with rather high folds, in transverse sections often of a palisade-shaped appear- ance. In the apex the folds were often a little branched. The structure of the radial muscles in the oral disc is the same as that of the longitudinal muscles of the tentacles ; the folds were, however, lower here, and so was the ectoderm. The ectoderm of the actinopharynx was, in the ridges, very high and contained very closely packed nematocysts, (26)29 — 36x3 — 3,5 /t in size, in the furrows considerably lower and with sparser nema- tocysts. The size of the nematocysts and spirocysts in four specimens was as follows (p. 181). The pairs of mesenteries were in 5 examined specimens 24 (6 + 6 -f- 12). The mesenteries of the third cycle showed the same differentiation as in E. marsufialis, in as much as half the pairs had reproductive 2»* Fig. 180 Textfigs. 179 — 180. Epiactis arctica. i8o ACTINIARIA Size of the body Nematocysts of the column Tentacles nematocysts spirocysts Nematocysts of the actinopharynx Number of tentacles Sp. I. length 2,7 cm, breadthi,? cm - 2. — 3 - — 3 - - 3. — 2,1 - — 0,9 - - 4- — 3.1 - — 1.7 - 31—37 X 2,5—3 fl| 29—36x2,5—3 31—37x2,5—3 30—36x2,5—3 25—30x2 — 2,5 n 26 30 X 2 24 27 X 2 24 30 X 2 19 X I — 32X2,5 (X 19X1 — 31x2,5 19x1—34x2,5 19x1—34x2,5 29—36 X 3,5 ^l (26)29—35x3—3,5 31—36x3—3,5 29—34x3—3.5 36 31 38 organs and filaments, the other half none. The latter occupied the same place as in E. marsupialis. The mesenteries with filaments commonly were perfect, the mesenteries of the third cycle, however, did not always reach the actinopharynx, which may be concluded from the number of tentacles. The longitudinal pennons commonly were broad with palisade-shaped, rather high folds. The parietobasilar and the basilar muscles were like those of E. marsupialis. Oral stomata were present; I have not observed any marginal stomata. Three examined specimens were females, two males. The above description is based on the material from the expedition of "Michael Sars". Systematic remarks. I have, though with some hesitation, identified this species with Verrill's Pseudophellia arctica, especially on account of Verrill's description of the cuticle ("thick and soft") and the presence of brood-rooms in the proximal part of the body. Verrill, however, declares that his species has a greater number of mesenteries ("24 perfect pairs with a few imperfect ones"). Still Verrill's description is rather imperfect. A control examination of the mesenteries, as well as a study of the nematocysts, are necessary, to decide whether Verrill's species is identical with the species, described here. The species is very nearly allied to E. marsupialis, and I was at first inchned to place them together. On account of the different appearance of the cuticle in both species, in marsupialis it is thin and soUd, in arctica thick and soft, and of the greater length of the nematocysts in the column in arctica, I think that they are not identical. The above named nematocysts of E. arctica are namely also in small specimens shorter than those of E. marsupialis. Also in some other characters the species seem to disagree. The species described below is also nearly related to both these species, from which it differs by a regular development of the mesen- teries of the third cycle. Epiactis nordmanni n. sp. Diagnosis: Column in contracted state conical, in height surpassing the diameter of the body. Column without a cuticle(?). Fossa distinct. Sphincter palmate. Tentacles conical, rather small, not or slightly longi- tudinally sulcated, 48 in number, hexamerously arranged. Actinopharynx long, with about 24 longitudinal ridges and two well developed siphonoglyphes with distinct gonidial tubercles, but without aboral prolong- ations. Pairs of mesenteries 24, all perfect in three cycles. lyongitudinal muscle pennons of the mesenteries rather strong, broad, the muscle folds of uniform breadth. Parietobasilar muscles strong, almost reaching the sphincter. Oral stomata present but no marginal stomata. Dioecious. All mesenteries with reproduct- ive organs and filaments. Nematocysts in the ectoderm of the column 26 — 31 X 2,5 ji, in the tentacles 22 — 26 X 2 //, in the actinopharynx 31 — 36 X 3 — 3,5 //. Spirocysts of the tentacles 19 X i — 24 X 1,5 /z. Colour in alcohol: Column olive-brown, tentacles pale salmon-coloured. ACTINIARIA jgj Dimensions: I,ength of the column 2,2 cm, largest breadth 1,2 cm. Length of the tentacles about 0,4 cm. Occurrence: Greenland. Nordre Stromfjord, 325 — 330 ni. Temperature at the bottom — 0,1° (Nordniann 191 1 St. 3 a) i sp. Exterior aspect: The form of the body is the same as in the former species. The single spec- imen was a little contracted, one part of the tentacles was however conspicuous. The column was a little longitudinally wrinkled, the fossa was deep. The tentacles were 48, hexamerously arranged, as many as the mesenteries, and all of about equal length, the inner, however, thicker, conical. Their surface was smooth or indistinctly longitudinally sulcated. The oral disc was inconsiderable, the actinopharynx long with distinct siphonoglyphes, having well developed gonidial tubercles, but no aboral prolongations. Anatomical description. The ectoderm of the column is rather high and contains numerous nematocysts, finely -grained gland-cells and sparser mucus-cells. Concerning the size of the nematocysts and spirocysts, compare above. I have not observed any cuticle, nor any of the spots on the column, which are present in E. arctica. The mesogloea is tliicker than the ectoderm, the endodermal circular muscles strong, and recall those of the fonner species. The spliincter is palmate and much recalls the reproduced sphincter of E. arctica but is devoid of a main lamella and, on account of the contraction, a little compressed. The longitudinal muscles of the tentacles and the radial muscles of the oral disc agree with those of the former species. The pairs of mesenteries are 48 in number (6 + 6 + 12). All the mesenteries of the third cycle were of about the same size and had well-developed filaments and reproductive organs. All mesenteries are perfect. The longitudinal pennons were somewhat broad, with rather high folds, all of about the same length. The parieto basilar and basilar muscles are not different from those of E. arctica. The specimen was a male, with well developed reproductive organs. Systematic remarks. The species is distinguished from E. niarsupialis and arctica by the consist- ency of the column, and by all the mesenteries of the third cycle being equally developed. The tentacles are also a httle more numerous, and the size of the nematocysts of the column differing from that of E. arctica. As the specimen was considerably smaller than the larger specimens of E. arctica and marsupialis, but nevertheless had all the mesenteries of the third cycle equally developed and furnished with filaments and reproductive organs, I think that it may be a particular species. It is most nearly aUied to E. marsupialis. Epiactis incerta n. sp. Diagnosis: Column not elongated , without a cuticle and particularly differentiated spots. Fossa distinct. Sphincter strong, palmate. Tentacles from conical to cylindrical, rather broad, smooth, 28 in number. Actino- dm dm pharynx sulcated with two siphonoglyphes. Pairs of mesenteries 14 (6+4+4; 13213211123123). Long- itudinal muscle pennons ver>- strong with high and concentrated folds. Parieto-basilar muscles very strong, almost reaching the sphincter. Oral stomata and marginal stomata present. Dioecious. Nematocysts in the ectoderm of the column 24 — 31 X 2 — 2,5 [i, in the tentacles 22 — 26 X 2 /i (also smaller 15 — 17 x i,5//), in the actinopharynx 36 — 46 X 3,5 — 4,5 fi. Spirocysts of the tentacles ig X 1,5 — 36 x 2 «. l82 ACTINIARIA Colour? Dimensions in contracted state: length and breadth about 2,2 cm. Occurrence: 20' E. off Cape Jakan 12 fms. Sand and clay with stones (Vega-Exp.) i sp. Together with E. marsupialis. Exterior aspect. The pedal disc is well developed and the column smooth, without spots. The fossa is deep, the tentacles from conical to cyUndrical, smooth and rather thick, in number probably as many as the mesenteries. Only about 20 tentacles were, however, perspicuous, but as I have observed some involved tentacles in the weakest compartments, I think that the number of tentacles and mesenteries is the same. Concerning the appearance of the actinopharynx I cannot give any perfect informations, as it was very contracted and badly preserved, and partly in a mess with the reproductive organs. It is, however, distinctly longitudinally sulcated. Anatomical description: The ectoderm of the column is high and contains numerous mucus- cells and nematocysts (size compare the diag- nosis). The mesogloea is thick, and the en- dodermal circular muscles much weaker than those of the former species. The sphincter is of a decidedly palmate type (textfig. 182), on transverse sections round and well-developed. The ectoderm of the tentacles is high, the nematocysts and the spirocysts (compare the diagnosis) numerous. Their longitudinal nmsc- les (textfig. 181) are strong, and recall those of Cribrina spetsbergensis, but are ectodermal; there is but rarely a mesogloeal mesh at the base of the muscle folds. The radial muscles of the oral disc are weaker, especially at the insertions of the mesenteries. Here the muscles seem to show a tendency to become mesogloeal, whereas they are ectodermal between the mesenteries. The nematocysts of the actinopharynx are numerous (size compare above) . The ectoderm and also the endoderm of the siphonoglyphes are very high, an ectodermal longitudinal muscle layer is present. The mesenteries are hexamerously arranged, though even at the origin of the second cycle the devel- opment of certain pairs of mesenteries is checked. If we mark with figures the different cycles of mesenteries and begin with the one directive pair (dm), the arrangement is the following. Fig. i8i Fig. 182 Textfigs. 181, 182. Epiactis incerta. Transverse sections of part of a tentacle (fig. iSi) and of the sphincter (fig. 182). dm dm 13 213211123123 14 pairs (6 + 4 + 4). The pairs thus were equally checked on both sides of the directive plane. In two primary exocoels, one on each side of the one directive pair, there are no mesenteries of the second and third cycles, and in the other primary exocoels the mesenteries of the third cycle are present only in the exocoels of the second ACTINIARIA 183 order next to the other directive pair. Supposing that the mesenteries are developed according to the same rule as in Urticina, the ventro-lateral mesenteries of the second cycle are absent, and among the mesenteries of the third cycle only the dorsal pairs in the primary dorso-lateral and lateral compartments are developed. All mesenteries seem to be perfect ; possibly one or other pair of the third cycle may be imperfect, but I cannot decide this, because of the bad preserv^ation of the specimen. The longitudinal muscle pennons are strong, the folds are very liigh and palisade-shaped, the main folds often have small secondary folds, issuing from both sides. The parietobasilar muscles are strong and recall those of the former species. Oral and marginal stomata are present, though not large. The single specimen was a female with numerous, very large ova. The mesenteries of the first and second order incl. the directives were fertile, on the microscopically examined mesenteries of the third cycle I have not observ^ed any reproductive organs. All mesenteries are furnished with filaments, most weakly developed on the mesenteries of the third cycle. Systematic remarks. This species is most nearly related to E. marsupialis and arctica, because of the arrangement of the mesenteries. I think that it is a distinct species, as also the nematocysts of the actino- pharynx differ from those of the former species. Fam. Paractiidae. Diagnosis: BasUaria with a commonly smooth, rarely tuberculated column, which is devoid of sucking warts (present in "Tealidium" cinctum ?) and acrorhagi. Sphincter weak or strong, always mesogloeal. Tentacles commonly short, on the outside of the base often bulbous, sometimes (in Anthosactis and Tealidium) with a stinging battery in the same place. Mesenteries now typically arranged, but sometimes after another cardinal number than 6, with both mesenteries in the same pair of the younger cycles either equivalent or differently developed, now arisen bilaterally onh' in 12 exocoels, when the 24-mesenteries stadium has been reached. Always without acontia. The following genera have been placed in this family by various authors: Actinernus Verr. Actinostola Verr. Alloactis Verr. Ammophilactis Verr. Antholoba R. Hertw. Anthosactis Dan. Antiparactis Verr. Archactis Verr. Raphactis Verr. Sicyonis R. Hertw. Aulorchis R. Hertw. Cymbactis Mc. Murr. Hormosoma Steph. Kadosactis Dan. Kyathactis Dan. Lilliella Steph. Marsupifer Carlgr. Ophiodiscus R. Hertw. Stompkia Gosse. Synanthus Verr. The new genera I have proposed are: Epiparactis Carlg. Parasicyon is Carlgr. Paractinia Andr. Paractis M. Edw. Paranthus Andr. Parantheoides Carlgr. Phclliomorpha Carlgr. Phelliopsis Verr. Pycnanthus Mc. Murr. Polysiphonia R. Hertw. Tealidium R. Hertw. Synsicyonis Carlgr. Some of the old genera are imperfectly known, some others do not belong to the family, and still others are to be regarded as synonyms. It is, therefore, necessary to discuss the genera more closely. g ACTINIARIA AcHnernus: I have (1918) shown that the type A. nobilis Verr. belongs to the Halcuriidae = Endo- coelactiidae. For A. saginattis (Verr.), plebeius (Mc. Murr.) and aurelia (Steph.), which are really Paractids, we must establish a new genus ^. Actinostola (type A. callosa Verr.) is a good genus, characterized by various authors and treated also in this paper. Alloactis (type A. excavata (R. Hertw.)) is a synonym for Anthosactis and must be dropped (compare Anihosactis p. 191). Ammophilactis (type A.rapiformis I^es.). The diagnosis, given by Verrill (1S99 p. 213), shows that the genus is different from Paranthus. "The reduced and feeble base" possibly indicates that the genus does not belong to this family but to the Halcampidae. A closer examination is desirable. Aiitholoba (type A. reticulata Couthony = achates (Drayton)) is a good genus and characterized by Hertwig (1882), Carlgren (1898) and Mc. Murrich (1904). Anthosactis (t3^e A. jan mayeni Dan.) is a distinct genus and easily identified (compare this paper). Antiparactis (type A. lineolata (Dana? Mc. Murr.) = dubia n. noni. Verrill (1899 p. 212)). Con- cerning this genus compare the genus Pycnanthus in this work, where a diagnosis of the genus is given. Archactis Verr. (t37pe A. perdix (Verr.)) Verrill has (1899 p. 209) proposed this genus for Urticina perdix. I have had the occasion to examine a specimen of this species, which the "Riksmuseum" in Stock- holm has received from the United States National Museum, wherefore I can supply the statements of Verrill concerning its organisation. In fact, it agrees very well with Antholoba.The sphincter is reticular and very long in both genera, the longitudinal muscles of the tentacles are weak and ectodermal in Archactis as well as in Antholoba, in the latter genus with a httle tendency to be ecto-mesogloeal in their basal parts. The radial muscles of the disc are of a similar appearance in both genera and are ecto-mesogloeal (I wrote 1898 p. 29 that these muscles are mesogloeal in Antholoba, it is more correct to designate them as ecto-mesogloeal). The whole organisation of both species is the same; the appearance of the column, the undulated disc, the numerous small tentacles and mesenteries, of which a great deal are perfect, the muscles of the mesenteries, all agree. I have stated 1898 that the mesenteries of the first to the third orders are sterile in Antholoba. As far as I can see, the fertile mesenteries only begin, also in Archactis, on the mesenteries of the fourth order (on the other hand Verrill declares that all mesenteries in A. perdix, belonging to the first five cycles except the directives, are fertile). Thus I think that A. perdix is an Antholoba. The nematocysts of the column of this species were 19 — 26 x about 2 ^, those of the tentacles partly 14 — 19 X 1 n, partly 24 — 29 x 1,5 /i, partly 29 — 34 X 2,5 ;u, those of the actinopharynx partly 14 — 17 X I (i'5) fi, partly 24 — 30 x 2,5 /i. The spirocysts of the tentacles were 19 x 1,5 /< to 38 x 2,5 //. Aulorchis (type A. paradoxa R. Hertw.) belonging, according to Hertwig, to his family Liponemidae. The exterior of this genus, the number and structure of the tentacles (the suppositional weak development of these latter is certainly connected with their being more strongly contracted and more badly preserv^ed than in Sicyonis crassa), the structure of the oral disc and the appearance of the siphonoglyphes agree with the corresponding facts in Sicyonis. H e r t w i g has not been able to determine how the mesenteries are grouped, ' Stepheiisen (1920 b p. 540) called thi.s new genus Aciinoscyphia. ACTINIARIA 185 but he adds that he is convinced that they are hexamerously arranged. The peculiarity of this genus should be that "the generative organs are modified into a single tube perforating the oral Up". Hertwig's descrip- tion of this tube is, however, founded on an examination of bad material and makes the impression that an abnormal formation was present. Though it is difficult to decide its nature on basis of the observations of Hertwig, I will, however, give as my opinion that the genital tube has arisen by regeneration and probably represents an additional actinopharynx, developed in a reproductive region (compare Carlgren 1904 p. II — 12). The whole formation is, however, so peculiar that a closer examination of it is necessary, before Hertwig's statement can be accepted. Disregarding this formation, I think that it is possible to place Aulorckis in the vicinity of Parasicyonis or Sicyonis. Cynibactis (type C. faecidenta Mc. Murr.). The description of the t5^e (Mc. Murrich 1893 p. 174) is in some respects incomplete. Still I think that we have to do with a distinct genus, characterized as follows : Paractiidae with well developed basal disc and thick crateriform body, with smooth, in contracted state rugose, column which is devoid of tubercles and acrorhagi. Sphincter muscle relatively weak, placed close to the endoderm. Margin tentaculate, not lobed. Tentacles short, acuminate and slender, not bulbous at the base, numerous. lyongitudinal muscles of the tentacles and radial muscles of the oral disc mesogloeal. 2 siphonoglyphes. Mesenteries hexamerously arranged, at least the first 2 cycles perfect. I/ongitudinal muscles of the mesenteries form no special pennons. Distribution of the reproductive organs? Mesenteries more numerous in the upper part of the column than in the proximal part. — This genus is separated from Pycnanthus by a richer development of mesenteries in the distal than in the proximal part, while in Pycnan- thus it is the opposite. From Mc. Murrich's description of Cynibactis we namely may conclude that it is so. Mc. Murrich speaks of the presence of 48 mesenteries (twenty-four pairs) but of 96 tentacles. As in Actininae we are not able to suppose a richer development of tentacles than of mesenteries, Mc. Murrich must have overlooked weak mesenteries in the most distal part of the body. Perhaps also the reproductive organs are differently arranged in the two genera. Of the other known Cynibactis I have placed C. actinosto- loides Wassil. and maxima Wasill. to Parasicyonis, and C. gossei Stepli. to Sicyonis (compare these genera). Hormosoma (type H. scotti Steph.). This seems to be a distinct genus (compare Stephenson 1918 a p. 29). It is easy to give a more complete diagnosis on basis of Stephenson's description. Kadosactis (type K. rosea Dan.). I have examined the single type-specimen. Owing to the bad pre- servation, especially of the filaments, wliich were totally macerated, I cannot definitively confirm the real position of this genus. The animal has a very strong sphincter and very strong longitudinal muscle pennons. I am inclined to consider this form as a Phellia. I will come back to this genus in the second part of this work.' Kyathactis (type K. hyalina) is an Actinostola (compare Actinostola spetsbergensis). Lilliella (type L. lacunifera Steph.). The position of this genus, proposed by Stephenson (1918 a p. 33) is dubious. The only specimen was namely badly preserved in the inner parts. The whole exterior of the species and the presence of only six perfect mesenteries indicate that the species belongs to the Chon- dractiniinae, viz. to a family with acontia. Marsupifer (type M. valdiviae Carlgr.) is synonymous with Haliatithella Kwietn. belonging to the family Halcampidae, and the species probably is the same as H. kerguelensis (Stud.). A closer examination of the The Ingolf-Expedilion. V. 9. 24 jjjg ACTINIARIA species has namely proved that the weak basilar muscles, which I supposed to be present, are not such muscles but the undermost part of the parietal muscles. The conclusion in my preliminary report of this genus that it was provided with basilar muscles, was somewhat hastily drawn, as the one species was flattened in the basal end and tlie other one, the contracted column of which was very low, was with a very broad base attached to a shell. This species thus has the power to considerably alter its basal end from rounded physa-like to a flattened wide basal plate , as it is also the case with Cactosoma and Milne-Edwardsia carnea (compare these forms). Thus the only criterion, if a genus is provided with a real pedal disc, is the presence of real basilar muscles. Ophiodiscus (type 0. annulatus R. Hertw.). This genus agrees with Sicyonis in the presence of con- siderably fewer tentacles than mesenteries, in the structure of the tentacles and of the oral disc, and in the differentiation of the mesenteries into sterile, filament-bearing and fertile, filament-loose mesenteries. Hertwig, however, (1882) does not mention a different development of both mesenteries of the same pair, which is possibly due to his having overlooked it, as the specimen was badly preserved. This is rather im- portant, as Hertwig probably has also overlooked the same case in Sicyonis crassa. The only obstacle put in the way of a conjunction of Ophiodiscus and Sicyonis, would be, that the tentacles of Ophiodiscus are arranged in a cycle and that they are very long. It ought, however, to be obser^^ed that the tentacles were for the greater part torn off and that only bad fragments of them remained. Hertwig 's figure of the exterior of Ophiodiscus is also very reconstructed. For my part I tliink that no conclusion, as to the real length of the tentacles, can be drawn on basis of the presence of the long tentacle-thread, as I have observed how very much prolonged perfectly slack tentacles of several Actinians can be. Finally, as to the supposed pre- sence of pseudo-tentacles in Ophiodiscus annulatus, it has not been proved that the single pseudo-tentacle observed belongs to the animal^. Neither has Hertwig dared to add it to the genus nor to the species char- acters (compare also Simon 1892 p. 9). The presence of pseudo-tentacles in a deep-sea form is also very unlikely. On basis of the named cases I think that Ophiodiscus is identical with Sicyonis or at least nearly alHed to it. Several authors as Mc. Murrich have referred Ophiodiscus to the family Lebruniidae. In reality this genus has nothing to do with Lebrunia, the structure of which is quite another. Paractinia (type P. striata (Riss.). During a visit in Turin 1899 Professor Rosa presented me with 2 specimens which he had seen living, and determined as this species. The exterior of both specimens agrees well with the description by Andres, and there were no acrorhagi. An examination of the sphincter showed that it was well developed diffuse, but endodermal and different from that of Actinia. As no reproductive organs were developed its definite position is somewhat uncertain, but I think that Paractinia is the same genus as Gyrostoma. Paractis type? It is questionable, which species of Paraclis, enumerated by Milne-Edwards, may be regarded as the type. Only when this has been determined, we may proceed to characterize the genus. Paranthus (type P. chromatoderus) (Schm.) and Parantheoides (type P. crassa Carlgr.). I have shortly characterized these genera (1898 p. 27). Concerning Paranthus I have shown, on basis of an examination of the type and of a species from N. America, that at least 12 pairs of mesenteries are perfect and that the re- productive organs arise already on the mesenteries of the first cycle. In opposition to this, Maguire (1898 ^ Stephenson (1920 p. 560- -561) is of the same opinion. ACTINIARIA 187 p. 723) has stated that only six mesenteries were perfect in the type and that the mesenteries of the first order were fertile in one examined specimen, sterile in another. I have controlled my earlier obser\^ations and examined in all three specimens of P. chroniatoderus. All three specimens were provided with 12 perfect pairs of mesenteries; the mesenteries of the second order do not reach as far down on the actinopharynx as the six first pairs. The two first cycles of mesenteries were fertile (2 specimens examined). Maguire has probably not sectionized the whole animals but drawn his conclusions from solitary sections. In the second Paranthus-species there were 3 cj'cles of mesenteries perfect, some of the mesenteries of the tliird cycle were perfect only in the uppermost part of the actinopharynx. Concerning the genus Parantheoidcs I think that we may place it together with Paranthus as synonym- ous with this genus. The only difference between the two genera is that Parantheoides is shorter than Paran- thus, but as the only dredged specimen was rather strongly contracted, it is possible that the difi'erence is not so considerable as might be supposed from the exterior. Phelliomorpha {type P. crassa (Dan.)) is synonymous with Cactosoma, belonging to the family Halcam- pidae (compare p. 124). Phelliopsis (type P. panamensis (Verr.)). If this genus, proposed by Verrill 1899 p. 214), really is devoid of acontia but has basilar muscles, wliich will have to be verified first, it may belong to the family Paractiidae and form a distinct genus. Perhaps it is related to "Paractis" ferax (Stuckej' 1909 P- 387)- Pycnanthus (type P. maliformis (Mc. Murr.)). This genus, characterized by Mc. Murrich (1893 p. 172) is a good genus. I have here given a more complete diagnosis of the genus and described two new species (compare further this genus). Polysiphonia (type P. tuberosa R. Hertwig (1882 p. 56)). This peculiar genus has been explicitly described by myself (Carlgren 1918 p. 36). Raphactis (type R. nitida Verr.) probably does not belong to tliis family. Possibly the genus is related to Korenia, Amphianthus etc. (compare Synanthus). Sicyonis (type S. crassa R. Hertw.) placed by Hertwig 1882 into a special family Sicyonidae, is, as I have before suggested (1899 p. 40), a Paractiidae (compare this genus). Stomphia [type S. coccinea (O. F. Miill.) = S. Churchiae Gos.) is, as I have before shown (1893), a distinct genus among the Paractiidae (compare this genus). Synanthus (type S. mirabilis Verr.). On the basis of Verrill's short and imperfect original descrip- tion (1879) of this genus, Andres (1883 p. 584) has suggested that it is a Zoanthid. It is probable that this suggestion is correct, which, however, cannot be decided until the type-specimen has been examined. On the other hand, I can verify that the species, which Verrill later (1883 p. 48 PI. 5 fig.9) describes as P. mira- bilis, belongs to the Zoantharia (s. str.). The verA- description indicates that we have to do with such an animal and a control examination of a specimen, received by The United States National Museum, proves the specimen to be anisozoanthus. I here give a short diagnosis of this species, still making the obser\'ation that the description of its exterior is imperfect, on account of the scarceness of the material: Polyps solitar>' or connected with each other by inconsiderable, thin coenenchyme. Basal plate wide. Column cyUndrical or conical. Tentacles well developed. Ectoderm of the column very high, continuous, 24* jgg ACTINIARIA very little incrusted (by spicula of sponges), provided with numerous oval nematocysts with very twisted threads, 19 — 25 X 7 — 8 fi in size. Mesogloea of the column thin, homogeneous, with sparse, scattered cells and cell-islets. Sphincter rather strong, endodermal, with few but rough folds. Nematocysts of the tentacles partly of the same kind as in the column and 17 x 7 — 22 X 8 (26 x 6) /« in size, partly narrower and broader in the basal end 22 — 24 X 3,5 — 4(5) fi, the spirocysts of the tentacles 17 X 1,5 — 2 to 26 X 3,5 /i. Ectoderm of the actinopharynx high, provided with nematocysts recaUing those of the tentacles, the former 19 — 22 X 8 — 7 ji, the latter 23 — 26 x 3,5 ii. A well developed siphonoglyphe. Mesogloea of the whole actinopharynx thin. Mesenteries 28, symmetrically arranged according to the macro-type, thickened in the distal part. Microcnemes well developed. Longitudinal muscles relatively strong in the macrocnemes as well as in the microcnemes. The species, described by Verrill (1899 p. 211) as Synanthus mirahilis, is, on the other hand, no Zoanthid. Though I have not seen this species, I am inclined to think that we have to do with a species of the genus Stephanaciis R. Hertw. (Stephanauge Verr.) = ? Amphianthus R. Hertw. = Korenia Dan., which are all provided with acontia, though, according to my examination, in small numbers. The family Amphian- tliidae, proposed by R.Hertwig (1882), cannot be maintained. The directive plane namely is not constant in relation to the longitudinal axis of the pedal disc or to the axis of the Gorgonian skeleton. Besides, I have found that the mesenteries of the first order, except the directives, are fertile in these genera. I will come back to these genera in the second part of this work. Tealidium (type T. cingulatum R. Hertw.) is a well marked genus. T. cincium Stuck, does not belong to the genus (compare below). According to this discussion, I think that the number of genera belonging to the family Paractiidae^ nmst be considerably reduced. I have before (1893, 1898) divided the Paractiidae into two subfamilies, Paractiinae^ and Actinostolinae. The Actinostolinae is also 1893 (Nachschrift) proposed as a special family). To these subfamilies I have (1918) added that of Polysiphoniinae, all based on the different development of the mesenteries. Of these subfamihes Polysiphoniinae is well limited. It is more difficult to have the two former distinctly separated. It is true, that it is easy to separate the typical Actinostolinae, Actinostola and Stomphia, perhaps also Sicyonis from the typical Paractiinae, but as we find traces of the Actinostolid-development in such ' Since this was written, Stephenson (1920 p. 504) sketches the line of evolution for the old Paractiidae and the old Sagar- tiidae, and derives both these families from an hypothetical ancestor, Eosagartia , at the same time dividing the Paractiidae into three, the Sagartiidae into five, partly new families. I will not enter on a closer critical discussion of Stephenson's h>-pothesis now, but keep it for the second part of this work. Meanwhile, I think that Stephenson's conclusions will have to be considerably modified. Accord- ing to my statements above, the division of the old Paractiidae into three families cannot be accepted. The representatives of the Marsupiferidae are Halcampids, and also the family Actinoscyphiidae must be dropped, based as it is on the presence of only 6 pairs of perfect mesenteries, while the new Paractiidae should have more than 6. The genus Antkosactis namely has 6, 8 or 12 perfect pairs of mesenteries. The genus, Tealidium, nearly related to Antkosactis, has at least 6 or 12 perfect pairs of mesenteries. Accepting Maguire's examinations of Paranthus as correct, this genus and even one and the same species should have now 6, now 12 pairs or in the Tybec- species 24 pairs of perfect mesenteries (compare above) . It is evident that under such circumstances the relations between the Sagartiidae and the Paractiidae will have to be seen from another point of view than that of Stephenson. Concerning the family Sagartiidae and Diadumenidae compare p. ig and p. 21. " I need not here further discuss Hertwig's formation of aspecial tribus Paractiniae for the genera Sicyonis and Polyopis, as this tribus was abolished long ago, nor the affinity supposed by Hertwig between the Sicvonidae and the Tetracorallia. It is inconceivable that such a well differentiated genus as Sicyonis should be nearly related to the primitive Tetracorallia. If a relationship between the Tetracorallia and the Actiniaria really is a fact, it must be between such primitive Actinians as the Halcuriidae and the Tetracor- allia (compare Carlgren 1918). ACTINIARIA 189 forms as Pycnanthus and possibly also in Parasicyonis (compare below) it is questionable, if the subfamily Actinostolinae may be maintained. The exterior of the Paractiidae is rather uniform, especially that of the column which is smooth or in a few forms tuberculated. Also the tentacles in the genera seem to agree well. They are commonly short, smooth, or in contracted state wrinkled, or sometimes longitudinally sulcated. In several forms they are more or less bulbous on the outside of the base as in Actinoscyphia, Pycnanthus lacvis, but not in P.densus and maliformis, Sicyonis crassa, tuherculata and ingolfi (but not in S. variabilis), Ophiodiscus and some Acli- nostola-species. As they sometimes appear only in certain species of a genus, their occurrence is rather in- significant as a genus-character, even in certain cases as a species character; I have namely in Actinostola callosa found all transitory stages between tentacles with bulbous thickenings [A. atrostoma) and tentacles without such (compare A . callosa) . This variation of a species does, however, not prevent that the bulbous thickenings may be more constant in other species or in certain genera. In the genera Anthosactis and Tea- lidium we meet with a special differentiation of the tentacles. At the sometimes thickened base of the outside of the outer tentacles there is a well developed stinging batterj^, containing large, closely placed nematocysts of a special appearance (compare these genera). Similar capsules, though considerably smaller, appear in Actinostola and Stomphia, but are here arranged mainly in the apex of the tentacles. The tentacles are commonly hexamerously grouped, in Anthosactis fan mayeni octomerously. In Stomphia the tentacles of the second cycle are twice the usual number or almost so, and the arrangement 6 + 12 + 18 etc. or 6 + 10 + 16 etc. Also in Sicyonis the tentacles are probably arranged in a similar manner. In Actinoscyphia they are found close by the margin of the oral disc in only two cycles. Possibly that is the case also in Epiparactis. In Polysiphonia the tentacles are placed in 12 triangular, continuous groups with the largest tentacles, corresponding to the first and second cycles of endocoels, in the innermost parts of the groups. The longitudinal muscles of the tentacles are wholly ectodermal in Actinoscyphia, Archactis (Antho- loba?) pcrdix, Anthosactis ingolfi, Antiparactis, Epiparactis, "Paractis" ignota and ferax and Paranthus, ecto- dermal to meso-ectodermal in Antholoba and Anthosactis fan mayeni, meso-ectodermal to ecto-mesogloeal ? in Anthosactis (Alloactis) excavata, and mesogloeal in Actinostola, Aulorchis, Cymbactis, Hormosoma, Ophio- discus, "Paractis" papaver and polaris, Parasicyonis, Pycnanthus, Polysiphonia, Sicyonis, Stomphia and Synsicyonis. The genera and species, with the longitudinal muscles of the tentacles either ectodermal or mesogloeal, have the radial muscles of the oral disc arranged in a similar way. In Antholoba and Archactis perdix they are more enclosed in the mesogloea and thus ecto-mesogloeal, in Anthosactis fan mayeni meso-ectodermal and in A. excavata ecto-mesogloeal. The siphonoglyphes are always present and well-developed. The mesenteries in most genera show a regular development and are commonly hexamerous, in Anthosactis fan mayeni octamerous. Both mesenteries of the same pair are for the greater part equivalent; in Actinostola, Stomphia, Sicyonis and perhaps also in some other genera they show a different development of the younger cycles. In the latter case they follow the Actinostola-vnXe. Traces of such an arrangement ■^^ ACTINIARIA 190 we find also in other genera (compare above). In Polysiphonia there are, when 12 pairs of mesenteries have regularly arisen, 12 development zones, in which the origin of new mesenteries takes place bilaterally from both sides of the exocoels towards the centre of these latter. Some genera show a richer development of mesenteries in the distal than in the proximal part. This is the case with Cymbactis, Synsicyonis and probably also with Antholoha (Archactis), in other genera the re- versed takes place as in Stomphia, Pycnanthus, Parasicyonis, Sicyonis and probably also in Ophiodiscus} Only six pairs of perfect mesenteries are present in Actinoscyphia, Epiparactis, Paranthus} (sometimes), Anti- paraciis and "Paractis" ferax. In the genus Anthosactis we meet in ingolfi 6 pairs of perfect mesenteries, in jan mayeni 8 and in excavata 12. In the other genera there are 12, or commonly more, perfect mesenteries. Also the distribution of the reproductive organs varies in the different genera. In the following genera (and species) the reproductive organs begin to develop on the mesenteries of the first cycle. Ammophilactis , Anthosactis, Hormosoma, "Paractis" .ferax, ignota, polaris, papaver , Paranthus, Phelliopsis and Tealidium. The producing of reproductive organs begins on the second cycle in Actinoscyphia and Antiparactis, on the third in Pycnanthus, Actinostola, Polysiphonia and Stomphia (partly), and on the fourth in Antholoha. In the following genera, Ophiodiscus, Parasicyonis, Sicyonis and Synsicyonis, as a rule only the mesenteries of the last order are fertile. In Parasicyonis these mesenteries are provided with filaments, in the other three genera not. The longitudinal muscles of the mesenteries are, in comparison to the size of the animal, rather weak and commonly form weak pennons or none. More developed they are for inst. in Hormosoma and Stomphia. The best developed pennons we find in elongated forms, such as in Paranthus and "Paractis" ferax. The parieto-basilar muscles are commonly well-developed, and so are also the basilar muscles. Genus Anthosactis Dan. Diagnosis: Paractiidae (Paractininae) with well developed basal disc, with smooth, rather low body-wall, which is devoid of tubercles, acrorhagi and spirocysts, but more or less distinctly longitudinally sulcated (in contracted state). Sphincter strong to very strong, not stratified, on transverse sections partite in small meshes. Tentacles short, not particularly numerous, broad at the base, thinner at the apex, often longitudinally sulcated, the inner longer than the outer ones or all of almost equal length. Outer cycles of tentacles on the exterior side at the base with a well-developed stinging battery containing very large, parti- cular nematocysts. Longitudinal muscles of the tentacles and radial muscles of the oral disc ectodermal to meso-ectodermal, those on the inner side at the base considerably stronger than those on the outer side. Oral disc very wide, in contracted state of the body strongly excavated. Actinopharynx short, with few ' It is true that Hertwig speaks of the presence of only 48 pairs of mesenteries and of almost 100 tentacles in Ophiodiscus annulatus, but a closer examination of the figure 3 PI. 10, encluding about one fourth of the oral disc, shows, that Hertwig has over- estimated the number of tentacles so as to double the number. Probably this mistake is due to the bad preservation of the tentacles or rather to an error in writing. If we namely consider the following suggestion by Hertwig, concerning the muscle-mesenteries (not the with these latter alternating fertile mesenteries) in Q.sulcalus (1882 p. 55) : "Da im Ganzen 48 Tentakein vorhanden sind, so wird sich die Zahl der Muskelsepten gleichfalls auf 48 oder auf 24 Paare belaufen", we find, that the number of mesenteries in this species is probably twice that of the tentacles. ACTINIARIA 191 longitudinal furrows and 2 siphonoglyphes. Few (6, 8 to 12) perfect pairs of mesenteries. L,ongitudinal muscles of the mesenteries comparatively weak. Reproductive organs present, at least on all stronger mesen- teries. Danielssen (1900) declares that the genus is provided with cinclides, and refers it to the family Sagartiidae. According to my examination of the tj^pe-specimen, no such cinclides are present (compare below!). The genus is besides a typical Paractiidae and easily recognizable on the structure of the tentacles, for one thing. Their longitudinal muscles are namely at the base much weaker on the outside than on the inside, and ectodermal to meso-ectodermal, perhaps sometimes ecto-mesogloeal (in A. excavata (R. Hertw.)). Furthermore, outer tentacles are at the base on the outside provided with a strong battery of very long and broad nematocysts of a characteristic type, an arrangement, observed by myself only in the genera Anthosactis and Tealidium. Probably this battery has the same function as the acrorhagi. To this genus I have before (1912 p. 43) placed Paractis excavata, described by R. Hertwig (1882), for which species Verrill (1899 p. 144) has proposed the name Alloactis excavata. The whole habitus and the anatomical structure of this species indicate that we have to do with a species of Anthosactis. It remains, however, to be ascertained, if the outer tentacles are provided with the above named particular nematocyst batteries. Anthosactis jan mayeni Dan. PI. 2. Figs. 6 — 7. Anthosactis jan mayeni n. sp. Danielssen 1890 p. 24, PI. 2 fig. i, PI. 10 fig. r. — — — Dan. Carlgren 1912 p. 21, 1916 p. i. Diagnosis: Pedal disc with a cuticle. Column with more or less distinct longitudinal furrows. Tentacles conical, longitudinally sulcated in contracted state, not hamiform, in 4 or 5 octamerously arranged cycles, of which the first and the second are very close. Inner tentacles thicker and longer than outer ones. Outer tentacles a little swollen at the base. lyongitudinal muscles on the outside almost exclusively ectodermal and not as strong as on the inside, where they are even meso-ectodermal. Oral disc with weak radial ridges and weak, partly mesogloeal muscles. Actinopharynx with few, longitudinal ridges. Pairs of mesenteries arranged octamerously (8 + 8 -f- 16 -f an imperfect fourth cycle in large specimens). Only 8 pairs perfect. Small oral stomata, no marginal stomata. Parietobasilar muscles broad but only a little folded, about two thirds as long as the mesenteries. Ectoderm of the column with nematocysts 22 — 24 X about 4 // (seldom 29 X 6 ;u) in size. Ectoderm of the tentacles with extraordinarily numerous spirocysts of variable size, unto 53x4 — (3 fi, and with very sparse nematocysts (26 — 29 X 4(5) fi). Stinging capsules in the battery of the outer tentacles very numerous 74 — 93 X 12 — 13 ^. Typical nematocysts in the ectoderm of the actinopha- rynx few 22 X3,5 (I, its nematocysts with distinct basal part to the spiral thread very numerous, 26 — 34 X about 5 fi. Colour of the column pale reddish- white, but on account of the red oesophagus it acquires a reddish tinge, while the uppermost margin is white. Tentacles rose-red, shading off a little into yellow. Oral disc darker yellowish-red with paler yellowish-white rays, radiating from the mouth towards the middle of the ACTINIARIA 192 disc. The gonidial grooves yellowish-wliite. When the animal is placed in alcohol the fluid becomes bright brownish- violet, and also the animal itself acquires a deep violet colour (Daniels sen). Dimensions in preserved state unto 3,4 cm broad at the base; length of the column 2,5 cm, length of the inner tentacles 0,8 cm, that of the outer ones 0,6 cm. Danielssen states the breadth to 4 cm. Occurrence: West Greenland. Baffin bay 75°26' N. bfzy' W. 250 fms. (Sofia-Exp.). Umanak 250 fms. (i860). East Greenland. 76°6' N. ifzb' W. 100—125 fms. (Danmark-Exp.) ; 72°25' N. i7°56' W. 300 m (Sw. Polar-Exp. 1900). Greenland without distinct locaUty. Jan Mayen (Norw. N. Atlantic- Exp. 1877). Kara Sea. 72°i9' N. 55°54' E. 90 m (Due d'Orleans-Exp. 1907). 73°34' N. 57°56' E. 60 fms. (Nova-Zembla-Exp. 1875). 73°38' N. 63°45'E. (Nordenskiold's- Exp. 1876). Exterior aspect: This species has been described by Danielssen before (1890), but in several respects erroneously. The pedal disc is provided with a well developed cuticle and is enlarged, but it is sur- passed in breadth by the oral disc, when the latter is expanded. The column is smooth, in contraction more or less wrinkled, without distinctly marked longitudinal furrows, corresponding to the mesenteries. As the animal is wholly extended the folds between the furrows disappear, wherefore the surface becomes smooth (Danielssen). A specimen, reproduced in the figure 6 PI. 2, is provided with some irregular apertures in the column. As far as I can see, these apertures are no cinclides, as Danielssen has supposed, but artificial pro- ducts, and probably apertures, remaining after the specimen's having been damaged and regenerated. In the other specimens I have not found any apertures, which speaks for the opinion that they are not normal formations. Besides, the column is rather thin (according to Danielssen, in extended state almost membraneous and transparent) ; in the distal part it, however, reaches a considerable thickness, owing to the strong development of the sphincter. No fossa is present. The tentacles are, as a rule, octomerously arranged in four cycles (8+8 + 16 + 32). The two inner cycles are, however, so close by one another that we can say that there are only three cycles, as Danielssen states. In the type-specimen and in a specimen, taken during the "Danmark"- Expedition, the number of tentacles was 64, in a third specimen there were 68 tentacles ; among these, four tentacles were of a fifth cycle, developed close by the one pair of directives, in a fourth there were 80 ten- tacles. In the last case there were i6'tentacles of a fifth cycle, in two octants, one of each side of the one pair of directives. The inner tentacles were only a little longer than the outer, but much broader. The form of the tentacles as usual conical, the outer tentacles were a little swollen on the outside at the base. All tentacles were in contracted state provided with distinct longitudinal furrows and with a distinct aperture in the apex. The oral disc was strongly excavated in the contracted state of the animal (fig. 6 PI. 2) and provided with distinct radial furrows, corresponding to the insertions of the mesenteries. As the oral disc is wholly extended, its diameter may be twice that of the pedal disc. The actinopharynx is short and provided with few (5 — 8) furrows and ridges on each side (PI. 2 fig. 7). The two, symmetrically situated, siphonoglyphes are broader in the oral part than in the proximal ACTINIARIA 193 Fig. 183 and, as Danielssen states, of an almost triangular form. In their uppermost part they are provided with distinct gonidial tubercles. Anatomical description. The pedal disc has a rather thick cuticle. The ectoderm of the column is somewhat low and contains rather numerous nematocysts 22 — 24 X about 4 // in size, and numerous mucus-cells. The meso- gloea is in the proximal part thin or of ordinary' thickness, corresponding to the different state of contraction, but swells out in the region of the sphincter and there forms a thick layer; it contains small protoplasma-poor cells. The endodermal circular muscles are weak, the mesogloeal sphincter, on the other hand, is very strong and juts out, during certain states of contraction, as a strong thickening towards the ectoderm, about as the sphincter of Tealidiutn cingulatum (Her twig 1882 PI. 6 fig. 2). In the upper part and in the greater part of its length it occupies almost the whole breadth of the mesogloea, proximally it decreases rapidly and takes up only the inner part of the mesogloea. The mus- cle meshes are very small, in certain parts very close, in other parts se- parated by larger lamellae of the mesogloea. Any distinct stratifica- tion of the sphincter is, however, not to be seen (textfig. 183). The ectoderm of the ten- tacles is very high and contains very numerous spirocysts of very vari- able size, unto 53 X 4 — 6 /i ; on the other hand, the typical nematocysts are very sparse and 26 — 29 X 4 — (5)/^ in size. In the swollen basal part, on the outside of the outermost tentacles, there is a specific stinging organ developed (textfig. 184) , which I have also observed in Tealidium jungerseni. This battery contains very numerous, closely packed nemato cysts (fig. 184 w) of considerable size (74^ — 93x12 — 13/!/), which are, however, smaller than those of Tea The Ingolf-Expedition. V. 9. J Fig. 185 Fig. 186 Textfigs. 183 — 186. Anihosactis jan mayeni. Fig. 183: Transverse section of sphincter. F"ig. 184: Transverse section of an outer- most tentacle, at the basis showing the battery of nematocysts (h). Figs. 185 — 186: Transverse section of an inner tentacle fig. 185 at the abaxiale, and fig. 186 at the adaxiale side. ^„, • ACtlKlAklA lidiiim but larger than those of Anthosactis ingolfi. The thread of the nematocysts is very twisted but is often scarcely visible in the maceration preparations; for the greater part it is only the very close points of recurvation of the thread which are seen through the wall of the capsule. The inner tentacles are devoid of such a stinging battery. The longitudinal muscles are, on the abaxial side at the base, weaker than on the adaxial, though also on the former side rather strong; further upwards the muscles of both sides are of about equal strength. On the abaxial side the muscles are mostly ectodermal, though also here and there muscles, enclosed in the mesogloea, appear (textfig. 185) ; towards the adaxial side the mesogloeal muscle-meshes are more numerous, so that the muscles may be called meso-ectodermal here (textfig. 186). The radial muscles of the oral disc recall those on the adaxial side of the tentacles and are meso-ectodermal and more strongly developed in the outer parts than in the inner, where they are rather weak. The ectoderm of the actinopharynx is somewhat low, especially in comparison to the mesogloea, and contains few nematocysts of typical appearance, about 22 X 3,5 (x long; on the other hand, the nematocysts with discernible basal part to the spiral thread are rather numerous. They are broader in the basal end and 26 — 34 X about 5 // in size. The mesenteries are octomerously arranged, which I have ascertained by the examination of several specimens and also of the type-specimen. Danielssen, however, declares that the mesenteries are hexam- erously arranged, but that is not the case and does not correspond with the arrangement of the tentacles, the agroupmentof which Danielssen has correctly stated. In the specimens with 64 tentacles the pairs of mesenteries were 32 (8 + 8 + 16), in those with 80 tentacles there were in one half, counted from the one directive pair, 20 pairs (4 + 4 + 8 + 4) developed. The four pairs of the last cycle are arranged in an octant next to the one directive pair. The arrangement of the tentacles on the other half indicates that also this part has the mesenteries grouped in the same manner. The eight first pairs of mesenteries are perfect. The longitudinal muscles of the mesenteries are not very strong and form no distinct pennons. The folds are however, numerous but low, with the exception of the innermost part, where they show a little tendency to form weak pennons; in the other parts of the stronger mesenteries they are uniformly developed. The parietobasilar muscles are distinctly marked, but the muscle lamella is not folded, it is extended over two thirds of the length of the column. The transversal muscles are rather well-developed in the distal part. The basilar muscles are well-developed and folded. A small oral stoma is present on the perfect mesenteries, on the other hand, there are no marginal stomata; I have, however, found a rather large aperture about in the middle of one 'mesentery. The'ciliated tract of the filaments is strong, its mesogloea thick and containing numerous cells. The species is dioecious; all mesenteries, at least in the specimens with 32 mesenteries, are fertile. The statement of Danielssen, that the 6(!) first pairs of mesenteries are sterile, is wrong. The acontia are absent. Anthosactis ingolfi n. sp. Diagnosis: Pedal disc without a cuticle. Column in contracted state with longitudinal furrows in the upper part. Tentacles conical, not longitudinally sulcated, in numbers 48 (6 + 6 + 12 + 24), of which the first and the second cycle are very close. Inner tentacles thicker and longer than outer ones. Longitudinal muscles of the tentacles ectodermal, on the inner side at the base very strong. Oral disc with ACTINIARIA 195 weak ectodermal, radial muscles. Actinopharynx with few (about 10) longitudinal ridges. Pairs of mesen- teries arranged liexamerously (6 + 6 + 12) ; only 6 pairs perfect. Parietobasilar muscles like those of A . jan mayeni. Typical nematocysts in the ectoderm of the column?, in the tentacles absent (? or if present very sparse). Particular stinging capsules of the stinging battery very numerous 53 — 75 X 11 — 13 /i. Spirocysts of the tentacles very numerous, from 22 X 2 /i to 55 X 3 (3,5) ^. Nematocysts with discernible basal part to the spiral thread in the actinopharynx rather numerous, 26 — 34 X 5 //. Colour? Dimensions: Breadth of the pedal disc 2,4 resp. 2,7 cm, length of the column in contracted state about 1,3 cm. Occurrence: 66°o8' N. i6°02' W. 729 fms. Bottom temp. — 0,8 (Ingolf-Exp. St. 125) 2 sp. Exterior aspect: The pedal disc is broad and does not seem to form any cuticle. The form of the body is in contracted state rather low and almost hemispheric. The surface of the body- wall is smooth; in the distal part there were indistinct longitudinal furrows present. The tentacles are short, the inner considerably broader and larger than the outer, in number 48, probably liexamerously arranged (6+6-1-12 + 24), the two first cycles are, however, very close. Because of the strong con- traction of the specimens it was difficult to get a satisfactory diagram of the arrangement of the tentacles. The form of the tentacles varies from cylindrical to a little conical ; I have not observed any longitudinal fur- rows on the tentacles, only indistinct transversal furrows, arisen by the contraction. The oral disc is very wide and smooth, and in contracted state deeply excavated. The actinopharynx is short and, on account of the contraction, transversally wrinkled, with aboral prolongations on the 12 perfect mesenteries, and pro- vided with 10 longitudinal furrows between the insertions of the mesenteries. Two siphonoglyphes are present. Anatomical description: The ectoderm of the column is thin and almost totally lost, so that I cannot give any information of its structure. The mesogloea is thin or of ordinary thickness, in the region of the sphincter, however, very thick. The sphincter is very strong and recalls that of A . jan mayeni. The muscle meshes are small and now very closely packed, now more sparse; the sphincter shows, as far as I can see, no tendency to stratification. The endodermal circular muscles are weak. The ectoderm of the tentacles is high and probably contains no typical nematocysts, if really present they are ver>- sparse. The outer tentacles are on the outside of the base provided with a stinging battery as in A. jan mayeni. The nematocysts are, however, smaller here and variate in both specimens between 53 and 75 // in length and II — 13 ^ in breadth. The spirocysts of the tentacles are extraordinarily numerous, between 22 X 2 to 55 X 3,5 [1 in size. The longitudinal muscles of the inner tentacles are much weaker on the outside of the base than on the inside. The inner folds are namely much closer and often more than double as high as the outer folds. They are often branched (textfig. 187 transverse section of inner tentacle). In contradistinction to 25* Textfig. 187. .-inthosactis ingolfi. Transverse section of inner tentacle. , ACTINIARIA 196 A. jan mayeni and A. excavata the muscles are not enclosed in the mesogloea but ectodermal. In the upper part of the tentacles the longitudinal muscles are weaker and uniformly distributed. The radial muscles of the oral disc is weak and ectodermal. The ectoderm of the actinopharynx contains rather few nematocysts with discernible basal part to the spiral thread, 26 — 34 X 5 /^ in size. I have besides in the maceration pre- parations found some small nematocysts and some spirocysts, but whether they belong to the actinopharynx or stick to the ectoderm, I cannot decide. The siphonoglyphes do not seem to be as sharply marked as in A. jan mayeni. Both specimens had 24 pairs of mesenteries, hexamerously arranged. Only the 6 first pairs were per- fect. The mesenteries were in both specimens much thinner than in A . jan mayeni, the folds of the longitudinal muscles are low and form no pennons. The parietobasilar muscles recall those of A. jan mayeni, but are weaker. The filaments have the same appearance as in this species. All mesenteries are fertile and provided with filaments. The animal is dioecious. Genus Tealidium R. Hertw. Diagnosis: Paractiidae with well-developed, enlarged basal disc. Column with numerous small papillae of the mesogloea, all of the same size, with more or less distinct longitudinal furrows, in contracted state very low, disc-like. Sphincter mesogloeal, very strong, in certain states of contraction issuing as a strong circular fold in the uppermost part of the column. Tentacles short, conical, hexamerously arranged, not numerous, the inner longer than the outer or almost of the same length. Stinging battery on the outer ten- tacles as in Anthosactis. Longitudinal muscles of the tentacles and radial muscles of the oral disc ectodermal. Oral disc wide. Actinopharynx short with two distinct siphonoglyphes. Pairs of mesenteries few, hexamerous- ly arranged, thin and with probably weak muscles. 6 pairs, or a few more, perfect. Reproductive organs appearing already on the mesenteries of the first cycle incl. the directives. The genus Tealidium is nearly related to Anthosactis with which it agrees in most characters, among others in the presence of the stinging batteries on the outside of the outermost tentacles. The nematocysts of these batteries are also of the same type as in Anthosactis. In contradistinction to Anthosactis its column is provided with very numerous, small mesogloea-papillae. Concerning the ectoderm of these papillae I cannot give any informations, as the ectoderm was lost in the specimens of T. ingolfi, as well as in the type-species. The diagnosis of the genus, given by R.Hertwig, is not good, as among the proposed genus-characters only one — the presence of the above named papillae — is preservable. The tentacles of the species, described below, are namely of different length. It is also questionable, if in T. cingulatum the form of the sphincter may serve as a diagnostic. I, for my part, am more inclined to regard the wall-shaped thickening of the meso- gloea in the sphincter region as due to a strong contraction of this part, because in the species, described below, and in one and the same specimen, the appearance of the sphincter varies in different places, evidently accord- ing to the state of contraction, and now recalls the sphincter of T. cingulatum, now is typically elongated. The species Tealidium cinctum (Stuckey. Trans. New Zeeland Instit.41. i9o8-i909,p.389) is certainly no Tealidium. Stuckey namely declares that the species is provided with "verrucae, which act as suckers, by which the animal covers itself with bits of shell and other debris." In the real Tealidium no sucking- ACTINIARIA ig- I verrucae are present, the papillae are namely here, as I have stated before, tliickenings of the mesogloea. If this species really is a Paractid, it must have a new genus name. I provisionally propose Paratealidiutn. Tealidium jungerseni n. sp. Diagnosis: Basal disc ver}- thin. Body-wall in the distal part with rather distinct longitudinal furrows. Spliincter now concentrated, now more elongated, not longitudinally stratified. Tentacles 48, conical, not longitudinally sulcated, with somewhat thickened mesogloea on the outer side at the base. Long- itudinal muscles of the tentacles rather well developed also on the outer side, though weaker here than on the inner side, with closely packed, palisade-shaped folds. Actinopharynx very short with about 6 longitudinal furrows on each side. Pairs of mesenteries 24, of which at least 6 pairs perfect. All mesenteries fertile. Nenia- tocysts in the ectoderm of the tentacles very sparse, 36x2,5 — 3^, its spirocysts verj^ numerous, 19x2 — 46 X 3 ;/. Nematocysts of the stinging battery on the outermost tentacles very large, 106 — 134 x 11 — 15 {i. Typical nematocysts of the actinopharynx partly 29 — 30 X 3 //, partly 20 — 25 X 2,5 ft. Nematocysts with discernible basal part to the spiral thread, 26 — 36 X 4 — 5 //. Colour? Dimensions: Height of the largest specimen 0,3 cm, breadth 3,5 x 2 cm. Inner tentacles 0,5 cm long. Occurrence: Danmark Strait. 64°34' N. 3i°i2' W. 1300 fms. Bottom temp. +1,6° (Ingolf-Kxp. St. 11) 3 sp. Davis Strait. 59°i2' N. 5i°05' W. 1870 fms. Bottom temp. + 1,3° (Ingolf-Bxp. .^Vl St. 38) I sp. Exterior aspect: The pedal disc is very wide. The body is in contracted state disc-like, in one specimen a little elevated in the middle (in the sphincter region), in the specimen from the station 38 the body forms a low cone. The column is provided with very numerous, closely packed, small mesogloea-papillae, all of about the same size, towards the distal end they are somewhat scarcer and seem, at least partly, to be lacking in the region of the sphincter (in the capitular region). In the two largest specimens this region was provided with some irregular protuberances, which may possibly have arisen by the strong contraction. The column is besides longitudinally sulcated, the furrows correspond to the insertions of the mesenteries and appear most distinctly in the distal, not involved part of the body. Sometimes transversal furrows are to be observed, they are certainly due to the contraction of the animals. The tentacles are thick at the base, tapering towards the apex, not longitudinally sulcated, and incurvate. In one specimen — I have exam- ined two specimens concerning the tentacles — the tentacles were a little swollen at the outside of the base. The number of tentacles was 48, probably (6 + 6 + 12 + 24). ^^^ oral disc is ver>- wide and thin, I cannot determine its structure as it was strongly extended, and its ectoderm lost. The actinopharynx is very short and provided with about 6 longitudinal furrows on each side of the sagittal axis. The two s}'mmetrically placed siphonoglyphes are provided with aboral prolongations. Anatomical description: The ectoderm of the column is lost, but to judge from fragments it seems to have been low. The mesogloea is in the greater part of the column rather thin and provided with igS ACTINIARIA the above named papillae; in the distal part, where the spliincter is situated, strongly thickened as in Antho- sactis. The spliincter recalls that of A nthosactis, sometimes it is wall-shaped, tliickened towards the ectoderm as in Tealidium cingulatum. As the sphincter in different regions of the same specimens of ingolfi displays both these appearances, I cannot find that the wall-shaped sphincter is efficient as a characterization of the species T. cingulatum. The endodermal circular muscles are weak. The ectoderm of the tentacles is liigh and contains very numerous spirocysts of varying size from ig x 2 /i to about 46 x 3 /i. The typical nema- tocysts are very sparse here as in Anthosactis jan maycni, and 36 X 2,5 — 3 /i in size. That also here stinging batteries appear in the same places as in Anthosactis I have ascertained on maceration preparations. The nematocysts were very close and were nmch larger than in Anthosactis, in as much as they vary from 106 to 134 /^ inlenght and II — 15/^ in breadth. They were of the same structure as in Anthosactis. The inner tentacles are not provided with stinging batteries. It is true, that I have at the apex of these tentacles found some scattered, large nematocysts of the same size as in the stinging batteries, but a closer examination proved that the nematocysts were sticking to the ectoderm and thus not belonging to this part. The longitudinal muscles of the tentacles are ectodermal^ and recall those of Anthosactis ingolfi (textfig. 188 transverse section of tentacle) as regards the distribution of the muscles. The folds are closer than in A. in- golfi. The niesogloea of the tentacles is from thick to rather thick, and some- what swollen on the abaxial side at the base. The radial muscles of the oral disc was badly preserved and, as far I can see, ectodermal. The ectoderm of the actinopharynx contains typical nematocysts partly 29 — 30 X 3 // , partly 20 — 25x2,5// in size, besides these, there are sparse nema- tocysts with discernible basal part to the spiral thread (length 26 — 36//, breadth 4 — $ fi). The mesenteries were in both specimens badly preserved and thin, so that I cannot give any informa- tion concerning the muscles, on all accounts there are no distinct longitudinal pennons. Probably the muscles of the mesenteries agree with those of Anthosactis ingolfi. The number of mesenteries was 48, 6 + 6 + 12 pairs, among these two directives, symmetrically situated. The first pairs are perfect, it seems, however, that also a few of the second order reach the actinopharynx ; the mesenteries of the third order occupy one half of the oral disc. The filaments were also badly preserved, the cnido-glandular tract contains very large mucus cells. The species is dioecious, and all mesenteries have reproductive organs. Textfig. 188. Tealidium jungerseni Transverse section of tentacle. Genus Epiparactis n. gen. Diagnosis: Paractiidae with well-developed pedal disc. Column not much elongated, smooth, with thick cartilaginous niesogloea, without distinct margin. Sphincter not strong. Tentacles rather short, the inner longer than the outer, conical, comparatively thin, whithout basal thickenings and stinging batteries on the outside of their base, closely packed on the outer rim of the wide oral disc, arranged in at least two, probably in three cycles. Longitudinal muscles of the tentacles and radial muscles of the oral disc ectodermal. ^ Possibly some few folds may fuse together. ACTINlARIA jQQ 2 distinct siphonoglyphes. Mesenteries numerous, thin, but only 6 pairs perfect. Muscles of the mesen- teries weak. Distribution of the reproductive organs? The below described species is probably nearly related to "Actinernus" saginatus and aurelia, but is distinguished from them by the tentacles being devoid of basal thickenings. Unfortunately, on account of the bad preservation of the specimen, I can neither decide, whether the tentacles are arranged in two or three cycles (compare below), nor how the reproductive organs are placed in the mesenteries. So far, it is the most practical to propose a new genus. If it were to be found out afterwards, that "Actinernus"'^ sometimes can be devoid of tentacle-tubercles, /. dtihia probably belongs to this genus. E. dubia n. sp. Diagnosis: Pedal disc with a cuticle. Sphincter comparatively weak, filling up only part of the mesogloea, not longitudinally stratified, consisting of small meshes, showing a tendency to transversal strati- fication, distinctly separated from the endodermal column muscles, and not continued in those latter. Ten- tacles smooth to indistinctly longitudinally sulcated, numerous (about 124). Longitudinal muscles of the tentacles and radial muscles of the oral disc ordinarily developed. Oral disc with radial ridges and furrows, especially well developed in the outer part. Actinopharynx of ordinary length. Siphonoglj^hes with aboral prolongations. Pairs of mesenteries hexamerously arranged in five cycles (6 + 6 + 12 + 24 + about 24, of which the last as a rule are developed only in the outer exocoels). Only 6 pairs of mesenteries perfect, lyongitudinal muscles form weak pennons only in the inner part of the mesenteries. Nematocysts in the tentacles and the actinopharynx numerous, in the former 26 — 34 X 4 — 5 pi, in the latter 24 — 41 X 3,5 — 5 pi. Spirocysts of the tentacles very numerous 19 X 1,5 — 2 to 67 x y fi. Colour? Dimensions: Length and breadth about 3 cm. Inner tentacles about 1,5 cm long. Occurrence: 6o°37' N. 27°52' W. 799 fms. Temp, at the bottom 4,5° (Ingolf-Exp. St. 78) i sp. Exterior aspect : The pedal disc is wide and deeply excavated, on account of its covering a sponge, of which rests remain behind. On several parts of the disc there are fragments of a cuticle. The column is about as long as broad, smooth and of about the same thickness as in Sicyonis. There is no distinct margin. The tentacles are broad at the base, diminishing towards the apex and rather short and thin. They are indistinctly transvers- ally wrinkled ; some of them are longitudinally sulcated. They are devoid of basal thickenings and basal stinging batteries. The inner tentacles are longer than the outer ones of wliich one part was very small. They were about 124 in number, a little fewer than those of the mesenteries. Their arrangement is difficult to determine, as the outer part of the oral disc was contracted and not well preserved, and small tentacles in development disturb their agroupment. Besides, they are closely packed on the outer rim of the oral disc. The tentacle cycles are possibly not more than 2 in number, at any rate not more than three. The oral disc is very wide and its greatest part without tentacles, in the innermost part smooth, in the outer with deep radial furrows. There are no gonidial tubercles. The actinopharynx is of ordinary length and irregularly wrinkled. The siphonoglyphes are distinct and provided with aboral prolongations. ^ Actinoscyphia (p. 184). 200 ACTINIARIA Anatomical description: The ectoderm of the column is almost lost, only in the uppermost part there are some fragments proving it to be thin. The mesogloea is very thick, of the same consistency as in Actinostola, fibrillar with scattered, small, often round cells. The endodermal circular muscles are weak. The sphincter is comparatively weak, the meshes placed in groups showing a tendency to transversal strati- fication; it is the strongest on the upper part and gradually becomes weaker downwards. It occupies only one part of the breadth of the mesogloea and seems to be wholly separated from the entodermal circular muscles (textfig. 189). The ectoderm of the tentacles is high and provided with numerous typical nemato- cysts, which are rather broad in comparison to their length (26 — 34 X 4 — Sn), and with very numerous spirocysts of very variable size (from 19 X 1,5 — 2 /z to 67 X 7 fi). The ectodermal longitudinal muscles are not strong, the folds are rather low and commonly not branched, but rather close (textfig. 191). There is no great difference in the development of the muscles on the adaxial and abaxial sides ; at the base the muscles, however, are a little stronger on the Textfigs, 189 — 191. Epiparactis dubia. Transverse sections of sphincter (fig. 189), of part of the oral disc (fig. 190) and of part of a tentacle (fig. 191) cm: circular muscles of the column. adaxial side, and the mesogloea likewise a little thicker on the abaxial side of the base. Still we cannot speak of basal thickenings of the mesogloea. The meso- gloea of the tentacles is commonly rather thin. The radial muscles of the oral disc is also ectodermal (textfig. 190), in its outer part stronger than in the tentacles and provided with rather high, close folds, of about the same dimen- sion at the insertions of the mesenteries as at the ridges. The ectoderm of the actinopharynx contains numerous ne- matocysts, 24 — 41x3,5 — 5// in size. The mesenteries are hexamerously arranged (6 + 6 + 12 + 24 + an imperfect fifth cycle). Only the 6 first pair are perfect. The imperfect mesenteries have been examined in ^/g of the animal. The mesen- teries of the fifth cycle were weak and generally present only ii: the outer compartments viz. beside the me- senteries of the first and second orders, sometimes they are lacking in some of those, sometimes they are also developed in the inner compartments beside the mesenteries of the tliird order. Both mesenteries of a pair were not developed in conformity with the Actinostola-rvle. The mesenteries ionn thin lamellae. Fig. 189 Fig. 190 Fig. 191 Genus Pycnanthus Mc. Murr. Diagnosis: Paractiidae with well-developed, enlarged pedal disc. Column smooth, without tuber- cles, in contracted state low and thin, sometimes with more or less distinct longitudinal ridges in the upper part. Upper parts of the column capable of involution. Margin tentaculate, distinct, not lobed. Sphincter weak or well developed. Tentacles short, only half as numerous as the mesenteries, the inner considerably stronger ACTINIARIA 201 than the outer, the latter without stinging battery at the base. Longitudinal muscles of the tentacles and radial muscles of the oral disc mesogloeal. 2 deep siphonoglyphes. Mesenteries hexamerously arranged, but not always regularly, at least the first 2 cycles perfect. lyongitudinal muscles of the mesenteries form no distinct pennons. Parietobasilar muscles more or less strong. Reproductive organs on the mesenteries of the third and fourth cycles, sometimes also on some of the fifth. No differentiation into filament-lacking fertile and filamentous sterile mesenteries. The weaker mesenteries, only in the most proximal part of the body, without filaments and reproductive organs. The diagnosis which I have given here of the genus differs considerably from the original diagnosis, proposed by Mc. Murrich (1893). That this latter was not suitable, may be concluded from the fact that Mc. Murrich later on (1904 p. 245) has placed to the genus a species Pycnanthus {Paractis) lineolatus, which, to my mind, cannot be conjoined with the type, maliformis. In P. lineolatus the longitudinal muscles of the tentacles and the radial muscles of the oral disc namely are ectodermal, its perfect pairs of mesenteries are only 6, and its reproductive organs are developed on the mesenteries of the second and third orders, characters which differ so much from the type that they make it impossible to place both species to the same genus. The reason why Mc. Murrich has enclosed them in the same genus, is that both specimens are provided with capitular ridges; I for my part am very sceptical as to the systematic importance of the capitular ridges, at least of such as are here appearing, which may very well have arisen by the contraction of the distal part of the column. Stephenson (1918 b p. 124) has drawn the same conclusion concerning Cym- bactis (= Sicyonis compare p. 211) gossei. According, to Mc. Murrich, the ridges besides should not be of the same structure in both species, in the type maliformis "hollow with rather delicate walls", in the species lineolatus "solid." In the below described species P. laevis, which in all other important characters agrees with the type, there are no distinct capitvdar ridges. I therefore think that the capitular ridges are without importance as a genus character, having probably in many cases arisen by contraction. As I have introduced them above in the diagnosis of the genus they might be used; I will, however, declare that they seem to be of small systematic importance. To the genus characters Mc. Murrich also adds, that the tentacles are "not swollen at the base". The below described P. laevis is, however, provided with such swollen tentacles. Mc. Murrich's Pycnanthus lineolatus must, to my mind, form a new genus type, with which possibly also Paractis tenmcollis may be placed. For this genus Verrill (1899 p. 212) has proposed the name Anti- paractis, type: A. lineolatus, which may be characterized as follows. The diagnosis is based on Mc. Murrich's description of the type. Paractiidae with well developed basal disc. Column smooth, without tubercles, in contracted state low and thin, sometimes with more or less distinct longitudinal ridges in the upper part. Margin tentaculate, not lobed. Sphincter strong. Tentacles short, only half so numerous as the mesenteries (always?). Outer tentacles without stinging batteries at the base. Longitudinal muscles of the tentacles and radial muscles of the oral disc ectodermal. Actinopharynx long with two siphonoglyphes. Mesenteries hexamerously arranged, only the 6 first pairs perfect. Longitudinal muscles of the mesenteries forming weak, broad pennons. Repro- ductive organs on the mesenteries of the second and third orders. No differentiation into filament-lacking fertile and filamentous sterile mesenteries. 26 The logolf-ExpedilioD. V. 9. ACTINIARIA 202 Verrill (I. c.) wishes to substitute the name dubia for lincolata, as he considers it questionable, if the species, described by Mc. Murrich, is identical with Dana's species lineolata. Also Mc. Murrich (1904 p. 247) is a little uncertain about the identification of his species with lineolata. Verrill suggests that the species is a Sagartiid, which "had lost its acontia." As far as I can understand, there is no reason for such a supposition. Pycnanthus laevis n. sp. PI. 3. Figs. 4, 5. Diagnosis: Body in contracted state usually disc-like. Column rather thick, in contracted state sometimes with indistinct longitudinal furrows in the upper part. Sphincter strong, longitudinally stratified. Tentacles usually conical or seldom more cylindrical, according to the state of contraction, 96 in five cycles. Outer tentacles at the base, on the abaxial side thickened and without longitudinal muscles. Pairs of mesen- teries about 96, the first, second, and one part of the third cycle perfect. Some pairs of the tliird cycle un- equally developed, consisting of a perfect and an imperfect mesentery. Mesenteries of the last cycle, only in the most proximal part of the body, very small, without filaments. Parietobasilar muscles rather well developed. Typical nematocysts in the ectoderm of the tentacles numerous, 22 X 2 — 31 X 2,5 /i, in the actinopharynx numerous, 25x2 — 31 X 2,5 //. Spirocysts in the tentacles very numerous, from 7 x i to 41 X 4,5 fi. Nematocysts with discernible basal part to the spiral thread in the ectoderm of the tentacles 31—36 X 3—3.5 !^- Colour in alcohol: uncoloured. Dimensions of the largest specimen in contracted state: diameter of the basal disc about 3 X 3,5 cm, height 0,6 cm. The smallest specimen was 0,7 cm broad and about 0,2 cm high. Occurrence: Davis Strait. 66°35' N. 56°38' W. 318 fms. Bottom temp. 3°9 (Ingolf-Exp. St. 32) many spec, on stones. W. of P'aroe Isl. 6i°3i' N. ii°36' W. 720 fms. Bottom temp. 2''4 (Ingolf-Exp. St. 46) several spec. Exterior aspect: The pedal disc is extended and most frequently thin. The fonn of the body is flat, almost disc-like when the animal is contracted, sometimes, as in the specimen reproduced in the fig. 5 PI. 3, the column forms a low cone. The surface of the column is smooth, excepting small irregular invagina- tions, arisen by contraction. The uppermost part sometimes shows indistinct longitudinal furrows, and, be- tween these, low ridges which are continued in the tentacles. These furrows and ridges are, however, not always distinct, it is thus probable, that they have arisen by the contraction of the distal part of the body- wall. The margin is distinct and not irregular. The outermost tentacles are small, arranged as palisades, and a little thickened quite at the base on the abaxial side; this thickening, being probably a continuation of the columnar ridges, however rapidly disappears. Mc. Murrich declares that the tentacles of the genus are not swollen at the base. As far as I can understand from Mc. Murrich's description of Pycnanthus maliformis, there may be a similar thickening as in P. laevis at the base of the outermost tentacles. Mc. Murrich (1893 p. 173) namely says: "The ridges upon the upper surface of the column run to the basis of the outer tentacles." The tentacles are conical, sometimes more cylindrical, according to the contraction. The ACTINIARIA 203 Fig. 19 Fi<»- 194 number of tentacles is about 96 (6 + 6 + 11 + 24 + 48), the inner are many times larger than the outer. Sometimes the tentacles are indistinctly longitudinally sulcated. The oral disc is wide, its larger part has no tentacles. It is provided with indistinct radial furrows, corresponding to the insertions of the mesenteries. Actinopharynx is of ordinary length, irregularly wrinkled and provided with 2 deep siphonoglyphes. Anatomical description: The ectoderm of the col- umn is almost lost, only a few fragments of it were present in several invaginations. In these fragments I found nematocysts, 14 — 17 X about I fi in size. Its mesogloea is thick and shows the same differentiation into two layers, an outer, provided with numerous cells and an inner, fibrillar and poor in cells, as that which I have described more in details for Sicyonis tuberculata. The endodermal circular muscles are weak, the distinctly longitudinally stratified sphincter, however, strong. In the uppermost part it occupies almost the whole breadth of the mesogloea, diminishes rapidly and passes into the endodermal circular muscles (textfig. 192, 193). The ectoderm of the ten- tacles is high with very numerous spirocysts (size : from 17x1 n to about 41 X 4,5 fi) and also rib-like typical nematocysts (size 22 X 2 — 31 X 2,5 //). Besides these, there are sparse nematocysts with discernible basal part to the spiral thread (size about 31 — 36 X 3 — 3,5/^). The mesogloea of the tentacles is thinner than the ectoderm. The longitudinal muscles form numerous, closely packed, radially extended meshes in the mesogloea. On the outside of the outermost tentacles, lowermost at the base where the me- sogloea is a little thickened, the longitudinal muscles are lacking, the muscle-lacking part, however, being inconsiderable (textfig. 194). Not far from the base, scattered muscle fibres namely ap- pear, rapidly increasing in number. The larger part of the outer tentacles displays uniformly extended muscles. The mesogloeal radial muscles of the oral disc are in the inner part of the disc weak and commonly only separated from the ectoderm by a thin lamella, in the outer parts strong with closely packed meshes, extended in ecto-endodermal direction. At the insertions of the mesenteries the mus- cles are interrupted by mesogloeal bridges. The ectoderm of the actinopharynx is of ordinary height and contains numerous nematocysts, 25 X 2 to 31 X 2,5 [i in size. Its mesogloea is thicker than its ectoderm, especially in the siphonogh'phes. Concerning the structure, the mesogloea of the actinopharynx agrees with that of the inner part of the column, in the siphonoglyphes and in the vicinity of these latter the meso- gloea is not so strongly fibrillar; here as in the Zoantharia there are also scattered ceU-islets. The number of the pairs of mesenteries is 96 or thereabout. The mesenteries are arranged in five 26» f- ^^^ I <33o Fig. 193 Textfigs. 192 — 194. Pycnanthus laevis. Fig. 192: Transverse section of sphincter. Fig. 193: Transverse section of part of the sphincter (in the fig. 192: indicated by dotted lines). Fig. 194: Trans- verse section of an outermost tentacle, next to its basis. „ , ACTINIARIA 204 cycles, of which the first and part of the third are perfect. Two examined specimens show the following arrangement of the mesenteries of the third cycle, counted from the one pair of directives i: imperfect, p: perfect mesenteries. Sp. I (sectioned in transverse sections): pp — pi — pp — pp — ip — pp — ip — ip — ip — pi — ip — ip. The mesenteries, designated by spaced out figures, are weaker than the other perfect mesenteries, and only reaching the actinopharynx with a small off-shoot. Sp. 2 (the largest specimen) only one half examined: ip — ii — ip — ii — ii — ii. As I have only macroscopicaUy examined this specimen, it is possible that some of the imperfect mesenteries are in reality perfect, but this I cannot with certainty decide as the specimen was rather badly preserved. On all accounts, the size of the mesenteries of the third cycle shows that one mesentery of a pair has grown more rapidly than its partner. A fully regular agroupment of these imperfect weaker and perfect stronger mesenteries does not seem to be present. The weakest mesenteries of the third cycle are, however, as in Actinostola spetsbergensis, commonly next to the mesenteries of the first order (compare P. densus). Both mesenteries of the pairs of the fourth and the fifth cycles seem to be equally developed. The sterile and filament-lacking mesenteries of the fifth cycle appear only in the proximal part of the body. The longitudinal muscles form no distinct pennons, though the outermost and innermost parts of the mesenteries show a weaker muscularity than the intermediate parts. The folds of the muscles in the best developed part are not especially strong, only the distal part shows high folds. The parietobasilar muscles are distinctly marked, but hardly form any folds; they almost reach the sphincter. The basilar muscles are distinct, though not strong, with few, rather high folds. Oral and marginal stomata are present on the perfect mesenteries. The ciliated streaks of the filaments are well-developed. The mesenteries of the third and fourth cycles have reproductive organs, the other mesenteries are sterile. The species is dioecious. Pycnanthus densus n. sp. Diagnosis: Pedal disc wide. Column thick, with indistinct, irregular longitudinal furrows. Sphincter rather long, reticular, not stratified. Tentacles short, but broad, conical, tliick and irregularly, transversely wrinkled in contracted state, about 90 to a little more than 100, and densely packed together, so that some tentacles are sharply outlined from each other at the base. Outer tentacles not swollen at the base. Radial muscles of the oral disc not distinctly interrupted at the insertion of the mesenteries, forming a net-work of large meshes close to the ectoderm. Pairs of mesenteries about 92 to 108, in four primary, symmetrically situated exocoels, more numerous than in the 2 other exocoels, which are situated on both sides of a directive pair. Sometimes there is a difference in size of both mesenteries of the same pair of the third and fourth cycles. Mesenteries of the last cycle only in the most proximal part of the body very small, without filaments and reproductive organs. Parietobasilar muscles distinctly outlined, reaching to the large marginal stomata. Typical nematocysts in the ectoderm of the tentacles numerous, 34 — 48 X 2,5 — 3 /i, in the actinopharynx 24 — 36 X 2 — 2,5(3,5) M- Spirocysts of the tentacles 22 X 1,5 — 2 to 58 X 3,5 (48 x 4, 5) fi. Nematocysts with discernible basal part to the spiral thread in the actinopharynx 20 — 29 X 3 — 5 fi. Colour? ACTINIARIA 205 Dimensions: Spec, i) diameter of the body a little above the pedal disc 4 cm, height 3 cm. Inner tentacles about i cm long and broad. The specimen 2 was smaller, but more strongly contracted. Occurrence: 64°53' N. io°o' E. 630 m. Temp, at 600 m. — 0,69 (Michael Sars-Exp. 1900 St. 10) I sp. (Sp. I). Norway-Bear Isl. 73°27' N. 23°!!' E. 460 m. Black, gray clay. Temp, at the bottom 2,67 (Swed.-Spitsberg.-Exp. 1898) i sp. (Sp. 2). Exterior aspect: The pedal disc was wide, in specimen i for the greater part torn off, so that only the outer part was left. The body of specimen i was in contracted state conical, of specimen 2 more cylindrical, the distal part of the body of spec. 2 bending outwards and downwards. The ectoderm of the column was lost, the thick mesogloea shows irregular, longitudinal, indistinct furrows. The margin is tentaculate. The tentacles, partly cover- ed by the column, are conical, about as long as broad, and irregularly, transversally wrinkled. The inner are considerably larger than the outer and show no basal tliickenings at the outside. The number of tentacles was in specimen i about 90, probably 92, in specimen 2 104. The tentacles are ver>- close and some- times almost fusing together at the base, especially in spec, i), so that the outhnes between them are indistinct; in such cases the mesenteries reach into the tentacles, as textfigure 195 shows. The oral disc is rather wide and ra- dially sulcated. The actinopharynx is well developed, with the deep siphono- glyphes being devoid of gonidial tu- bercles, but aborally prolongated. The actinophar>'nx is besides longitudinallj- Fig. 197 Fig. 196 Textfigs. 195 — 197. Pycnanthus densiis. Fig. 195: Transverse section of the basis of two tentacles [T). mc : mesentery, sulcated, in specimen 2 there are about Figs. ig6 — 197: Transverse sections of the oral disc fig. 196 in the outer fig. . . 197 in the inner part. 12 longitudinal furrows on each side. Anatomical description: The ectoderm of the column is lost, its mesogloea is fibrillar and provided with numerous, small, branched, protoplasma-poor cells. The sphincter is strong, and in the distal part it almost fills up the whole breadth of the mesogloea, but rather soon decreases. It is on transverse sections reticular and recalls the sphincter of Stomphia coccinea, though it is less strong and less long. I have not ob- ser\'ed any distinct stratification of the sphincter. The ectoderm of the tentacles is rather high and contains X 4 206 ACTINIARIA very numerous nematocysts and spirocysts. The size of the former is in spec, i 36 — 48 x 2,5 — 3 /i (commonly they are 41 — 43 ft long), in spec. 2 34 — 41 X 3 — 2,5 fi, the latter variates in spec, i from 24 X 1,5 /u to 58 X 3,5 n, in spec. 2 from 22 X 2 to 48 X 4,5 /x. The mesogloea of the tentacles is thicker than their ectoderm, the longitudinal muscles are found in the middle part of the mesogloea and show rather large meshes on trans- verse sections. The radial muscles of the oral disc (textfigs. 196, 197) are also mesogloeal, but approached to the ectoderm and in the outer part of the disc separated from it only by a thin layer of mesogloea (textfig. 196). The muscles seem to be continuous and not interrupted at the insertions of the mesenteries, the meshes of the muscles are rather large, Uke those of the tentacles. The mesogloea of the oral disc shows in the parts, which are not occupied by the muscles, a chondroid-shaped structure. Tlie ectoderm of the actinopharynx contains typical nematocysts, the size of which is in spec, i 29 — 36 ^ long and 2,5 // broad (a few nematocysts reach a size of 29 x 3,5 fi), in the spec. 2 24 — 31 X 2 — 2,5 //. Besides these, there are here numerous nema- tocysts with distinct basal part to the spiral thread, in spec, i 20 — 24 X 3 — 3,5 /i, in spec. 2 22 — 29 X 3,5 — 5 fi. In the maceration preparation I have found also spirocysts here, which, however, probably do not belong to the actinopharynx, but are attached to the ectoderm. The number of the pairs of mesenteries was in spec, i probably 92. On one side of the animal, counting from one directive to the other, I observed 48 pairs, on the other side I examined only the larger pairs, being 22 in number. As there are pairs, alternating with these latter, of wliich I have convinced myself by the examination of some compartments , the number of the pairs of mesenteries is on this side probably 44. If we indicate the different cycles by letters — the mesenteries of the first order by Roman figures — the arrangement of the pairs of mesenteries is as follows, {dm : directive mesenteries. Concerning the spaced out figures compare below!). On one side : dm. # 143545254534 154536564525453545 154536564525453545 = 48 pairs. on the other side: « dm. 43545254534 154536564525453-4- I 54536564525453-4-1 = 44pairs. As we see, the arrangement of the mesenteries is almost the same on both sides. The only difference is that 4 pairs of mesenteries of the fifth order are not developed on one side (in the lower line). On closer examination of the arrangement, it appears that it is irregular. In the primary exocoels, on both sides of one directive, we observe mesenteries of the second to the fifth orders, those of the fifth order are, however, de\'el- oped only between the mesenteries of the third and second cycles, but not between those of the third and first. In the 4 other primary exocoels the mesenteries are numerous and show the same agroupment in all 4, excepting that 4 pairs of mesenteries are lacking on one side. In all these primary exocoels, mesenteries of the second to the sixth cycles are developed, those of the sixth cycle are, however, limited to eight pairs, two in each primary exocoel, on both sides of a pair of the fifth order. Comparing this arrangement with that of the ActinostoUds we find a certain agreement. It is true, that both mesenteries of the same pair in the younger cycles of Pycnanthus densus generally are of the same size, but the failure or the retardation in the erection of the youngest cycles takes place in the compartments on the side, where the weakest mesenteries of the third ACTINIARIA 207 order should be situated, if the}' were developed as in Actinostola spetsbergensis. In this species the weakest mesenteries of the third cycle are found next to the mesenteries of the first cycle, the stronger mesenteries next to the mesenteries of the second order. In Pycnanthus densus we see that in the first compartments, next to the one directive pair, the mesenteries of the fifth cycle are lacking between the directive pair and that of the third order, while such mesenteries are developed between the pair of the third cj'cle and that of the second. In the other primar\' compartments there are mesenteries of the fifth order, except on one side where they are lacking in four exocoels, placed between the mesenteries of the tliird and first orders. In eight exocoels, four on each side, mesenteries of a sixth cycle are present. If these latter were established in strict conformity with the rule of Actinostola, they should appear between the mesenteries of the fourth and second cycles. They have, however, here arisen between those of the third and fourth cycles, which seems to be connected with the fact (in contradistinction to the Actinostola) that the weakest mesentery of the fourth cycle (in the scheme marked with a *) stands next to the pair of the second cycle, not as in Actinostola next to that of the third. The with a * marked pair of the fourth order namely shows a different development of both mesenteries in the same pair, one being perfect, the other not. The mesenteries of the second specimen were 216 in number. The arrangement of the 108 pairs agrees well with the agroupment of the mesenteries in spec. i. The mesenteries of the sixth cycle namely have arisen in the same secondary compartments (between the mesenteries of the first and second orders) as in spec, i viz. counted from the one directive pair in the secondary compartments 3 and 5, on each side of the directive plane (compare the arrangement in spec. i). The number of mesenteries was, however, in two such compartments a Httle more numerous here than in spec, i, namely 11 pairs in compartment 5 on one side, and in compartment 3 on the other, instead of 9 in the two other compartments and in the corres- ponding compartments of spec. i. In the other secondarj' exocoels there were mesenteries of the third to the fifth cycles, regularly arranged. Whether a difference in size exists between both mesenteries of the same pair in the mesenteries of the fourth cycle I cannot decide, as I did not want to cut up the specimen. For the same reason I have not examined the number of the perfect mesenteries here. The mesenteries of the three first cycles were perfect in specimen i. Two unpaired mesenteries of the fourth cycle besides reach the actinopharjmx, as above mentioned. In a couple of cases I have observed a slightly different size of both mesenteries of the third cycle, the weakest mesenter\' in the pairs is next to the mesen- teries of the first order. Though the arrangement of the mesenteries does not quite agree with that of the Actinostolids, it, however, seems to recall the latter. The mesenteries were provided with comparatively small oral, but with large marginal stomata. Their mesogloea is rather thick. The longitudinal muscles form no distinct pennons and show, on transverse sections, rather coarse folds, scattered over the whole surface. The parietobasilar muscles are distinctly outlined and reach the region of the marginal stomata. Through the growth of the parietobasilar muscles one part of these muscles becomes mesogloeal as in Stomphia. The reproductive organs of specimen i are found on the third, on the greater part (18 pairs) of the fourth, and on four pairs of the fifth cycle. In the scheme I have marked the fertile pairs with spaced out figures. The younger sterile pairs, 6 of the fourth order, 32 of the fifth and 8 of the sixth, are very weak , appear only in the most proximal part of the body, and are devoid of fila- o ACl'INIARIA 208 ments. In spec. 2 the third and fourth cycles and 6 pairs of the fifth were fertile. The other pairs of the fifth and sixth cycles were sterile and without filaments. Genus Parasicyonis n. gen. Diagnosis: Paractiidae with a well developed pedal disc. Body more broad than high. Column thick, smooth, without tubercles. Margin tentaculate without fossa. Tentacles rather short but broad, robust, in contractions wrinkled, the inner longer than the outer. Sphincter comparatively weak, so that the column commonly does not cover the tentacles. L,ongitudinal muscles of the tentacles and radial muscles of the oral disc mesogloeal. Two deep siphonoglyphes. Numerous perfect mesenteries. Mesenteries often a little irregularly arranged, both mesenteries of the last sterile cycle sometimes differently developed, so that one mesentery is perfect, another not, but not regularly arranged as in Actinostola. Number of mesenteries at least twice as large as that of the tentacles. Only the mesenteries of the last cycle fertile. These mesenteries do not reach the oral part of the column and are, like all the other mesenteries, provided with well-developed filaments. The genus Parasicyonis is certainly nearly related to Sicyonis, from which it is mainly distinguished through the fertile mesenteries having well-developed filaments with ciliated streaks, while in Sicyonis they are devoid of such, though they are sometimes rather well developed. Also the arrangement of the mesenteries seems to be different in both genera. Possibly it may later on be found out that they may be placed together to a genus, for the present I consider it the most practical to separate them. Excepting the type, P. sarsii, I place to the genus also P. actinostoloides and P. maxima, described by Wassilieff (1908) as belonging to the genus Cymhactis. The whole of their exteriors namely recalls that of P. sarsii, and the imperfect description, given by Wasilieff , in no way contradicts that we have to do with specimens of the genus Parasicyonis. According to me, the following specimens belong to the genus: Parasicyonis sarsii Carlgr. — actinostoloides (Wassil.) Carlgr. — maxima (Wassil.) Carlgr. Parasicyonis sarsii n. sp. PI. 3. Fig. 12. Diagnosis: Sphincter reticular, thin but rather long, often in the outer parts with traces of strati- fication. Tentacles commonly 86 to 103. About one half of the oral disc devoid of tentacles. Radial muscles of the oral disc interrupted at the insertions of the mesenteries, strong. Number of mesenteries about twice as many as the tentacles, or more. Mesenteries of the three first cycles and one part of the fourth perfect. Part of these latter consisting of a perfect and an imperfect mesenterv'. Arrangement of the mesenteries hexamerous but not regular. Longitudinal muscles of the mesenteries rather weak. Parietobasilar muscles broad, but weak. Nematocysts in the ectoderm of the tentacles numerous (26)29 — 43 X 2 — 2,5 //, in that of the actinopharynx 19 — 29(37) x 2 (1,5 — 2 (i). Spirocysts of the tentacles (14 X 1,5) 22 X 1,5 — 67 X 3,5 — 4,5 {i. Nematocysts with discernible basal part to the spiral thread in the actinopharynx 23 — 31 X 3,5 — 4,5 //. Colour: pale brick-red, shading off into orange (spec, from Drontheimfiord , Carlgren). Dimensions of the two largest specimens: length 4 cm, breadth of the pedal disc 8 cm, length of ACTINIARIA 209 the inner tentacles about 2 cm, the outer not half as long as the inner. The smallest specimen (with only 62 tentacles) is about 2 cm high and 4 cm broad at the pedal disc. Occurrence: Norway. FinmarkAndenesioo — 200 fms. (H. Kieri894) isp.,Drondtheim fiord, Garten 25om(i9io)isp., R0dberg2Oom2sp.,Tautra25o — 8om2sp.(i)Gunnerusoi92i). 62°i8' N. 4°i4' E. 370 m (Michael Sars-Exp. 1902 St. 60) i sp. 62°54' N. 9°i3' W. 460 m. Bottom temp. 4,37° (Michael Sars-Exp. 1902 St. loi) 2 sp. 15 miles E. of the northernmost Faroe Islands (taken with a line) (Michael Sars-Exp. 24. 7. 1900?) I sp. S. of Iceland 63°i5' N. 22°23' W. 326 — 216 m (Thor-Exp. 1903 St. 171) i sp. Exterior aspect. The wide pedal disc is somewhat broader than the column. The body is, in comparison to the breadth, low and forms a short cylinder. The column is smooth, firm and thick, sometimes with indistinct furrows, probably arisen by contraction. The margin is tentaculate without a fossa. The ten- tacles are thick, robust and conical, in contracted state longitudinally and transversally wrinkled, the inner are more than twice as long as the outer and in preserved specimens about half as long as the height of the column. They are not swollen at the base and rather scattered, so that they occupy about one half of the oral disc. The number varies between 62 in the smallest specimen and 103 in the largest. Five examined specimens had 62, 86, 90, 96, 103 tentacles, arranged in several cycles. In four of the specimens the tentacles were wholly visible, in the smallest specimen and in one of the largest the tentacles were partly covered by the column. It is, however, questionable, if the tentacles may be totally covered, as the sphincter is weak, in comparison to the size of the animals. The inner, tentacle-lacking part of the oral disc is provided with radial furrows. Both siphonoglyphes are broad and deep and aborally a little prolongated. The actinopharynx is long and provided with numerous longitudinal furrows. Anatomical description: The ectoderm of the column was for the greater part lost. It is thin and contains nematocysts, 17 — 22x1,5// in size. I have here, besides, found some nematocysts of the same size as those of the tentacles, but it is possible that they are fastened to the surface and thus not belonging to the column. The mesogloea, especially in some specimens, reaches a considerable thickness and shows a fibrillar structure with scattered, rather numerous, small cells. The sphincter is rather weak and somewhat elongated, but thin and only occupying part of the mesogloea. It was in two examined specimens, in all places reticular with small meshes, in the specimen from Andenes and from Station 60 the outer parts bore traces of stratification; the inner reticular part is separated from the outer by a lo:igitudinal, rather thick mesogloeal lamella. The ectoderm of the tentacles is rather high, though not as thick as the mesogloea, and contains very numerous nematocysts. The size of the nematocysts and spirocysts was in the different specimens as follows, a) typical nematocysts, b) nematocysts with discernible basal part to the spiral thread. Habitat Tentacles nematocysts spirocysts Actinopharynx a b 1 . Andenes 2 . S. of Iceland 3. St. loi "M. Sars" 4. St. 60 "M. Sars" 5. E. of Faro Isl 34—42 X 2,5 ,(( 29 — 41 X2 31-38x2(2,5) {26)34—41X2,5 36—43 X 2 24 X 2—67 X 3 .« 22 X2 60X4,5 22 X 1,5—62 X 3,5 14x1,5—58x3 24x1,5—58x3 19 — 26 >: 2u 22 — 26 X 2 22 — 26x1,5 — 2 24 — 29 X 2 25—37x1,5—2 26— 31x3,5— 4.5 u 26 — 29x3,5 — 4,5 24 — 26 X 4 23—29x3.5—4.5 26—31x3.5 The logolf-Expedition. V. 9. 27 210 ACTINIARIA In the specimens i, 3, 4, 5 I have found solitary typical nematocysts in the actinopharynx. They were a httle larger (29—38 X 2,5 11) than usual. Whether these nematocysts belong to the actinopharynx or are sticking to it, I cannot with certainty decide, in specimen 5 I observed only a few typical nematocysts in the maceration preparations, in the other specimens the nematocysts, put down in the table, were, how- ever, numerous. The mesogloeal, longitudinal muscles of the tentacles on transverse sections show meshes of ordinary size, which are situated now in the middle of the mesogloea, now nearer to the endoderm. In the textfig. 198 I have reproduced a transverse section of a tentacle : the muscles are weaker on the outer side than on the inner one. The radial mus- cles of the oral disc recall the longitud- inal muscles of the tentacles. They are the best developed in the specimens i and 5 (textiig. 199). They are distinctly interrupted at the insertions of the me- senteries. The number of mesenteries varies. In one half of specimen i with 96 tentacles I counted 54 pairs of mesenteries (27 pairs sterile and as many fertile) , in spe- cimen 2 with 90 tentacles the pairs of mesenteries were 94 (22 on one side and 25 on the other, sterile and as many fer- tile), in specimen 4 with 62 tentacles pro- bably 90 pairs of mesenteries half of which sterile, in the specimen 5 with 86 tentacles 86 (18 pairs on one side and 25 on the other, sterile and as many fertile). As we see, the arrangement of the mesenteries was different on both sides of the directive plane. In one half of specimen i the mesenteries of the first to the third cycles were perfect, among the mesenteries of the fourth cycle three pairs reached the actinopharynx, six pairs consisted of a per- fect and an imperfect mesentery and three pairs were imperfect like the mesenteries of the fifth and sixth orders. In specimen 4 there were in the whole animal probably 26 pairs perfect and three pairs consisted of a perfect and an imperfect mesentery. In specimen 5 I observed on the less developed side eleven pairs perfect and three consisting of a perfect and an imperfect mesentery, on the other side probably thirteen pairs perfect and four pairs consisting of a perfect and an imperfect mesentery. The pairs, showing a different develop- ment of both their mesenteries are, as far as I can see, irregularly arranged. Half the mesenteries are sterile, the other half fertile, the latter are the younger and have well-developed filaments with cihated streaks like the other mesenteries, but never reach the distal part of the column. The longitudinal muscles of the mesenteries are rather weak and hardly show any distinct pennons. The parietobasilar muscles are broad and reach far upwards, but consist of a non folded muscle lamella. Oral stomata are present. In two specimens I have also observed marginal stomata, but they do not seem to be constant. The ciliated streaks are well developed. Fig. 198 Fig. 1 99 Textfigs. 198 — 199. Parasicyonis sarsii. Transverse sections of tentacle (fig. 198) and of oral disc (fig. 199). ACTINIARIA 211 Genus Sicyonis R. Hertw. Diagnosis: Paractiidae with well developed, enlarged basal disc and from rather tliick to thick, cartilaginous, smooth column, which, in contracted state, is sometimes somewhat sulcated in the upper part and here capable of involution. Sphincter weak or rather well developed. Tentacles short, the inner considerably stronger than the outer ones, often more or less thickened on the outside of the base and in that case with the longitudinal muscles stronger on the inner, weaker on the outer side or disappearing at the base, only about half as numerous as the mesenteries. Longitudinal muscles of the tentacles and radial muscles of the oral disc mesogloeal. 2 broad siphonogly'phes. The arrangement of the mesenteries is not as regular as in Actinostola, variable, but with a strong tendency to a different development of the two mesen- teries in the same pair. Often 16 pairs of perfect mesenteries, a variable number of pairs, in which one mesen- tery is perfect, the other not. Mesenteries with no distinct longitudinal pennons. Parietobasilar and basilar muscles well-developed. Mesenteries differentiated into stronger sterile mesenteries with well developed filaments and into weaker fertile without filaments, the latter appear at the Umbus and grow from here in oral direction but do not reach the most distal part of the column. Among the species described below, Sicyonis tuberculata and ingolfv are nearly allied to the tj'pe- species Sicyonis crassa. The agreement is so perfect in important characters, as f. inst. in the presence of mesogloeal muscles in the tentacles and in the oral disc, in the arrangement of the reproductive organs on filament-lacking mesenteries of the last order, in the number of tentacles in comparison to that of the mesenteries etc., that there is no doubt that nw species belongs to this genus. It is true, that the tentacles of Sicyonis crassa, according to Hertwig, seem to be much more reduced than in my species, but tliis differ- ence is, however, to ni}' mind, only apparent, as the strong contraction and the bad preservation ^ in connec- tion with a flattening of the tentacles in 5. crassa have produced the tubercle-shaped appearance of the tentacles in the type. Thus it is to be supposed that the tentacles of 5. crassa have had about the same ap- pearance as those of 5. tuberculata and ingolfi. Also the large apertures in the apex of the tentacles in the type are certainly artificial products, due to bad preser\-ation (compare further 5. variabilis). Though Sicyonis variabilis, described below, differs from the above named species in the arrangement of the mesenteries, it seems to me that this species manifestly belongs to this genus. To the genus Sicyonis Cymbactis gossei, described by Stephenson (1918 b p. 123), probably also may be referred. The whole organisation namely indicates that we have to do with a Sicyonis, unfortunately Stephenson does not mention whether the fer- tile mesenteries are devoid of filaments or not. Concerning the other species of Cymbactis, C. selaginella, des- cribed by Stephenson (1918 a), may be a S^om/ife'a^ (compare this genus), and C . actinostoloides Wasil. and C. maxima Wasil. belong to the genus Parasicyonis (compare p. 208). R. Hertwig 1888 has described a new species Sicyonis elongata. I cannot, however, arrange this species in the series of Sicyonis, on account of the comparatively small breadth of the pedal disc and the pre- sence of fertile mesenteries in the distal part of the body instead of in the proximal part, as in the real Sicyo- 1 The Actinians from the Challenger-Expedition are generally very badly preserved and their original shape often greatly altered by the pressure, of which I have been able to convince myself during a visit in London 1897. 2 After this was written Stephenson (1920 1. c. p. 559) has come to the same conclusion. 27* ACTINIARIA 212 «ts-species. Manifest!}- a reversed case takes place, compared with Sicyonis, here we find the mesenteries to be more numerous in the distal than in the proximal part, there they are more numerous in the proximal part, here we probably find a greater number of tentacles, corresponding to the richer development of the mesenteries in the distal body-end, there fewer tentacles in number, corresponding to that of the sterile me- senteries. The arrangement of the mesenteries is, besides, so imperfectly known that we cannot with certainty place this species in the vicinity of the genus Sicyonis, though much in Hertwig's description speaks for it. For the present I should like to propose a new genus Synsicyonis for Sicyonis elongata, which I pro- visionally characterize as follows: Paractiidae with the basal disc not enlarged. Column thick, cartilaginous, smooth. Sphincter, ten- tacles, oral disc and siphonoglyphes as in Sicyonis, the number of tentacles, however, about the same as that of the mesenteries. Arrangement of the mesenteries probably recalling that of Sicyonis (or of Actinostola?) but irregular "owing to the alternation of isolated genital mesenteries with isolated complete ones." Mesen- teries differentiated in stronger sterile and weaker fertile ones, the latter only in the distal part and without filaments. According to me, the following species may be referred to the genus Sicyonis: S. crassa R. Hertw. 5. gossci (Steph.) Carlgr. S. tubcrculata Carlgr. S. ingolfi Carlgr. S. variabilis Carlgr. Sicyonis tuberculata n. sp. PI. 3. Figs. 2—3. Diagnosis: Body, according to the dift'erent state of contraction, flat or more cyhndrical, commonly not high. Sphincter rather well developed, sometimes weak with groups of small meshes, encircled by stronger stripes of mesogloea. Tentacles about 64 to 68 with very strong, swollen mesogloea on the base of the outside. Apertures in the apex of the tentacles small. Longitudinal muscles of the tentacles on the inner side divided in closely packed, but large, meshes, on the outer side considerably weaker and disappearing at the base. Radial muscles in the outer part of the oral disc developed as on the inner side of the tentacles, interrupted at the insertions of the mesenteries. Actinopharynx longitudinally sulcated. Siphonoglyphes very elongated towards the aboral end. Pairs of mesenteries about 64 — 68, of wliich one half stronger, sterile and with well developed filaments and longitudinal muscles, the other half alternating with these latter, with weak muscles, fertile, generally without filaments, and extended only in the proximal parts of the body, from which they read: a longer or shorter way upwards, in as much as the reproductive organs are more or less developed. Commonly 16 pairs of perfect mesenteries. The rest of the filamentous pairs often symmetrically arranged on both sides of the directive plane, but the arrangement is not regular as some mesenteries of one and the same cycle arise earlier in certain exocoels than in others. Mesenteries of the pairs mostly differently developed, some of them reaching the actinopharynx with only one mesentery of each pair. Ivongitudinal muscles of ACTINIARIA 213 the mesenteries diffuse. Parietobasilar muscles differentiated, much expanded on the mesenteries. Basilar muscles with rather numerous, closely packed, high folds. Oral stomata present. Marginal stomata as a rule on the stronger mesenteries. Nematocysts in the ectoderm of the tentacles 19 — 34 X 2,5 n, in the actino- pharynx 24 — 31 X 2,5 ju, here also nematocysts with discernible basal part to the spiral thread 24 — 29 X 5 /i. Spirocysts in the ectoderm of the tentacles of variable size 22 X 2 to 55 X 5 fj. Colour in alcohol white, oral disc brown, actinopharynx dark brown. Dimensions of the largest specimen. Length 4 cm, breadth 4,5 cm. Occurrence: Davis Strait. 66°35' N. 56°38' W. 318 fms. Bottom temp. 3,9°. (Ingolf-Exp. St. 32) 8 spec. Danmark Strait. 64°34' N. 3i°i2' W. 1300 fms. Bottom temp. 1,6°. (Ingolf-Exp. St. 11) 4 spec. Exterior aspect: The form of the body varies rather considerably, according to the different state of contraction of the animals, now it is strongly flattened (PI. 3 fig. 2) now more cylindrical (PI. 3 fig. 3). The pedal disc is wide, the column smooth and irregularly sulcated.in the uppermost part, in certain specimens, with longitudinal furrows, surpassing the limit of the mesogloeal bridges of the tentacles. Neither a fossa nor a distinctly marked margin are present. The tentacles on the outside display very large thickenings of the mesogloea, prolonged far upwards. The distal part of the tentacles is conical or cylindrical with a small aperture in the apex. In some tentacles the apertures are very large, but they are artificial, due to bad preservations. The tentacles are about 64 to 68, arranged in several cycles and thinly scattered. Owing to the strong contraction of the animals I have not been able to determine their arrangement. The tentacles may be totally covered by the column. The oral disc is wide, provided with radial furrows and, in the state with involved tentacles, strongly excavated. The greater part of the oral disc bears tentacles. The actinopharynx is not long, longitudinally sulcated and provided with two broad, symmetrically placed siphonoglyphes. These latter have well developed aboral prolongations and in the oral region two distinct gonidial tubercles. Anatomical description. The ectoderm of the column is almost totally lost in all specimens. In a specimen there remain just above the pedal disc some fragments, containing very numerous nematocysts, 17 — 19 X 2 ft large; the mesogloea was ver>' thick, cartilaginous and unequally structured in the outermost and in the inner parts. The former is namely provided with numerous ca\dties, containing cells, while the latter are of more t}TDical appearance with scattered protoplasma-poor cells. Unfortunately I cannot give a good description of the former as the mesogloea was not well preserved. The endodermal circular muscles are rather weak, the mesogloeal sphincter of some specimens rather strong, of others, as well as of the largest specimen, weak. In the latter case it only occupies a small part of the breadth of the mesogloea, in the former it is about half as broad as the mesogloea. Also in one and the same specimen the strength of the sphincter may vary in different parts, possibly owing to a different contraction of the tissue. The sphincter is rather elongated and gradually passing into the circular muscles of the endoderm. It is close by the endoderm and shows no distinct longitudinal stratification, though the muscles seem to have been enclosed in the mesogloea during different periods. The meshes are small and arranged in groups, surrounded by somewhat broader balks of the mesogloea (textfig. 201, transverse 214 ACTINIARIA Textfigs. 200 — 201. Sicyonis tuberculata. Transverse section of tentacle near its base (fig. 200) and of the middle part of the sphincter (fig. 201). section of sphincter in its middle part). The ectoderm of the tentacles is on the base of the outside low, on tlie inside a little thicker, more upwards the ectoderm of the outside is also thicker. It contains rather numer- ous to numerous nematocysts, 19 — 34x2,5 // large, and ver\' numerous spirocysts of variable length, from 22 X 2 to 55 X 5 /< (3 specimens examined). The tentacles are devoid of longitudinal muscles on the abaxial side at the base, more upwards there are solitary muscle-meshes in the mesogloea (textfig. 200, transverse section of tentacle near its base) , and in the distal part, above the swelling of the mesogloea, numerous meshes of the same size as those at the adaxial size, where the muscle-meshes are numerous also at the base. The muscle meshes are more or less delicate and often elongated in radial direction. The mesogloea is considerably thicker than the ectoderm, excepting at the apex of the tentacles. The radial muscles of the oral disc recall the outer tentacle-lacking parts of the longitudinal muscles of the tentacles and form thin meshes, elongated in the di- rection from the ectoderm to the endoderm. At the insertions of the mesenteries they are interrupted by thicker mesogloeal balks. In the vicinity of the actinopharynx the muscle meshes are small and few. The ectoderm of the actinopharynx is rather high, strongly pig- mentous and contains numerous, typical nematocysts, 24 — 31 X 2,5 ;^ in size, and rather numerous nematocysts with discernible basal part to the spiral thread (size 24 — 29x5 ft. 3 specimens examined). The arrangement of the mesenteries is rather peculiar and shows a tendency to an octomerous development, in as much as often 16 pairs are perfect; there are besides some fewer or more numerous pairs, of which one mesentery is perfect, the other not. We also often may find several imperfect pairs of mesenteries of which one mesen- tery is more strongly developed than its partner. I have, however, not made any observations, definitely proving the mesenteries to be arranged, according to the same distinct law as in the Actinostolids, though the mesenteries on both sides of the directive plane are often symmetrically grouped. Five examined specimens show the following arrangement of the stronger mesenteries. Issuing from one directive mesentery we follow the mesenteries as the figures on a dial and, if necessary, call the mesentery next to the directive mesentery a, its partner b. (The reproductive mesen- teries are not enumerated in the scheme). The following pairs of mesenteries were perfect in: Sp. I (St. 32) I, 3. 6, 7, 9, 12, 13, 15, 17, 19, 21, 22, 25, 27, 28, 31 PW.- .,-<>.'??<: ' #A^ 9^ 3 * t* ft Fig. 200 Fig. 201 Sp. 2 (St. II) Sp. 3 (St. II) Sp. 4 (St. II) Sp. 5 (St. 32) I. 3. 6, 7, 9, 12, 14, 16, 18, 20, 22, 24, 27, 29, 30, 33 I. 3. 6, 7, 9, 12, 13, 15, 17, 19, 21, 22, 26, 28, 32 16 pairs (textfig. 202 B). 16 pairs (textfig. 202^). 15 pairs (textfig. 202 C). ACTINIARIA 215 As we see, in specimens i — 3 the same pairs of mesenteries are perfect. In specimen 5 we find mainly the same arrangement of the mesenteries. At the end of one half, the arrangement of the mesenteries is, however, disturbed by an extra filament -bearing mesentery- 25 being intercalated. Besides, one of the pairs of mesenteries, which are perfect in specimens i — 3, does not reach the actinopharynx here. The spec- imen has only 15 perfect pairs. In specimen 4, wliicli is pro\-ided with 34 stronger pairs of mesenteries instead of 32 as in specimens i — 3, part of the perfect pairs of mesen- teries are of another number than in the latter spec- imens. If we imagine that the also here developed ex- tra-mesenteries (.r) had not arisen, the arrangement of the perfect pairs of mesen- teries would be the same as in the three first specimens. The following pairs of mesenteries consist of a Textfigs. 202 A, B,C. Sicyonis iuberculata. perfect and an imperfect Diagrams of the arrangement of the mesen- teries. In figs. 202 A and B only the sterile mesenteries are reproduced. Compare the text ! Sp Sp Sp Sp 23b 24a 26b 29b 30a = 10 pairs (202 B) 1 6b 1 8a 23b 26b 30a = 8 — 1 6b 1 8a 24a 30a = 6 — 17b 19a 26a ^5 — (202 A) " 24a 29b 31a = 5 — (202 C) mesentery. The letter indi- cates the perfect mesentery . Sp. I. 4b lob iia i6b 18a 4b 8a lob 4b lob 4b lob 4b lob The three iirst specimens as well as the greater part of the specimen 5 fully agree. It is true that the same mesenter>' is not always perfect, owing to the different number of the pairs, consist- ing of an imperfect and a perfect mesentery which are present in the five specimens, but it is the same a and b mesenteries which are per- fect in the pairs. Now one pair, now another thus seems to grow more rapidly. Besides, it ought to be observed that also several pairs of imperfect mesenteries show a different development of both mesenteries in one and the same pair. So the perfect mesentery 8 a in the specimen 2 corresponds to a stronger imperfect mesentery 8 a in the specimen i.The perfect mesentery 11 a in the specimen i is adequate to a stronger imper- fect mesentery 11 a in the specimen 2, and this is also the case with the mesentery 24 a. If we disregard the presence of the extra pairs of mesenteries x (compare above) in the specimen 4, the arrangement of the me- senteries is also here the same, 17 b corresponds to 16 b, 19 a to 18 a, 26 a to 24 a. How this peculiar arrangement has arisen, is difficult to decide. As to the place of the mesenteries Fig. 202 C , ACTIN1AS.IA of the first order I think that I am able to draw a definite conclusion. An examination of the expansion of the mesenteries on the pedal disc in four specimens namely distinctly shows, where the mesenteries of the first cycle are situated. On the textfigures 202 A — C I have marked these mesenteries with I. On closer examina- tion of these textfigures we find that in two primary exocoels of the first order, one on each side of a directive pair, one pair of mesenteries of the second order (II) and two pairs of the third (III) have been developed (the fertile mesenteries are not included), while the mesenteries are more numerous in the other primary exocoels. In these latter I cannot with certainty determine which mesenteries belong to the second cycle. It is, however, worth noticing that the mesenteries are equally situated in all these four primary exocoels. For my part, I am still inclined to suppose that the mesenteries of the second order have been doubled in these four exocoels. Under this supposition the perfect pairs of mesenteries would consist of 6 pairs of the first and 10 pairs of the second order. If this supposition is correct, the arrangement of the mesenteries namely may be parallelled with that of the Actinostolids. On the above reproduced textfigures the different develop- ment of both mesenteries of one pair of the mesenteries of the second order is not discernible at the actino- pharynx, which, on the other hand, is the case at the pedal disc. On the textfigure 202 C I have designated the approximate extension of the stronger mesenteries on the pedal disc with spaced-out Unes. The mesen- teries of the first order reach the nearest to the centre of the pedal disc, the directive pair which is turning down- wards on the figure is shorter than the five other pairs. In the remaining pairs — which we suppose to be of the second order — we see both mesenteries of the same pair differently developed. They foUow the rule, char- acteristic of the ActinostoUds, the stronger mesenteries namely turn their longitudinal muscles towards the lateral mesenteries of the first order and towards the directive pair, situated upwards on the figure; viz. to- wards the oldest mesenteries, the first, second and third couple during the development. From tliis we may conclude that the double number of mesenteries of the second cycle probably has arisen in the lateral and ventrolateral primary exocoels. Supposing this to be the case, we may also explain the different development of the mesenteries in one and the same pair of the mesenteries of the third cycle. Also these mesenteries namely likewise follow the Actinostola-rale, though the development in the many exocoels has become more irregular, probably in connection with the doubling of the mesenteries of the second order. Concerning the latest developed (fertile) mesenteries it ought to be observed that I have not always been able to determine a different size of both mesenteries of one and the same pair, on account of the specimens not being well pre- served, the thick mesogloea of the older mesenteries causing some difficulties at the dissection, and the repro- ductive organs sometimes being so strongly developed that they hide the other inconsiderable parts of these mesenteries (compare below). On the textfigure 202 C I have therefore marked the fertile mesenteries as if they were equally developed. I have, however, been able to ascertain that also here sometimes traces of a different development of both mesenteries of the same pair are present. For all these reasons I think that Sicyonis is rather nearly related to the Actinostola and Stomphia. Alternating with the stronger, generally sterile pairs of mesenteries (32 in the specimens i — 3, 33 in the specimens 5 and 34 in the specimen 4) there is a cycle of fertile mesenteries (fig. 202 C), which are now very small and provided with few reproductive products, now longer with very large reproductive products. These mesenteries arise at the pedal disc and grow upwards, but never reach the distal body-end. Exception- ACTINIARIA 217 ally some of the smallest mesenteries of the third cj-cle bear reproductive organs. This is the case with the pairs 5 and 29 of the specimen 2, and the pairs 2, 23 and 25 of specimen 5 ; in the latter specimen they agree with the other fertile mesenteries, in the former they were provided with filaments. The longitudinal muscles of the mesenteries are well-developed with closely packed , high folds , expanded over the whole surface and not forming pennons. The parietobasilar muscles are well marked, broad in the lower part and reaching far upwards as a narrow lamella, their folds are, however, ver\' weak in the lower part, in the upper part the muscles form an even lamella. The mesogloea is thick in the stronger mesenteries, thin in the fertile. The greater part of the latter is occupied by the reproductive organs, only a little part next to the column is muscular. The muscle folds are also here numerous on the longitudinal muscle-side, so that we may say that the muscles of the fertile mesenteries form a miniature of those of the sterile mesenteries. Oral stomata are present. The stronger mesenteries are also generally provided with marginal stomata. The filaments of the sterile mesenteries are of typical appearance, the ciliated streaks are well-developed. The fertile mesenteries, excepting the above named, are completely devoid of filaments, as far as I can see, wliich is in conformity with Hertwig's observations of the type-specimen, 5. crassa. The species is dioe- cious. The ova are numerous but small. Sicyonis ingolfi n. sp. PI. 3. I'ig. I. Diagnosis: Body rather low. Column in the uppermost part with longitudinal furrows. Sphincter as in the former species feeble with a tendency to stratification. Tentacles about 68, the outer with large, the inner with weak, abaxial, bulbous thickenings at the base. Apertures in the apex of the tentacles small. Longitudinal muscles of the tentacles and radial muscles of the oral disc as in 5. tuberculata, only feebler. Actiuopharynx and siphonoglyphes as in the former species. Pairs of mesenteries 68, 34 with well developed filaments and rather well developed muscles, sterile, 34 without filaments, fertile, only present in the proximal part of the body. 16 pairs perfect. Both mesenteries of the same pair of the other stronger mesenteries some- times unequally developed, so that one mesentery is perfect, the other not. Muscles of the mesenteries about as in S. tuberculata, but feebler. Oral and marginal stomata present, the latter at least on some of the stronger mesenteries. Nematocj'sts in the ectoderm of the tentacles 36 — 41 x 2,5 n, in the actiuopharynx 29 — 36 (38) X about 3 fi. Nematocysts with discernible basal part to the spiral thread in the actiuopharynx 26 — 29 X 5 ;/. Spirocysts of the tentacles from 24 X 2 ;/ to 62 X 4 /u. Colour in alcohol: white, the actiuopharynx uncoloured. Dimensions in contracted state: I^ength 3 cm, breadth 4 cm. Occurrence: South of Greenland. 58°2o' N. 48°25' W. 1695 fms. Bottom temp. i°5 (Ingolf-Exp. St. 20) I sp. Exterior aspect. The exterior of this species (PI. 3 fig. i) recalls that of 5. tuberculata. The longitudinal furrows in the uppermost part of the column are more distinct, as in this species. Only the outer tentacles are provided with strong mesogloeal thickenings on the abaxial side, the inner tentacles are also here a little thickened, though by far not as much as in the former species. The tentacles are closer than in The Ingolf-Expedition. V. 9. -g 2l8 ACTINIARIA S. tuberculata, wherefore the tentacle-lacking part of the oral disc is large. The actinopharynx is of ordinary length. In the other exterior characters this species agrees with S. tuberculata. Anatomical description: The interior organisation also much recalls that of S. tuberculata. The nematocysts are, however, larger, especially those of the tentacles. The ectoderm of the column contains rather numerous nematocysts, 17 — 22 X 2 ;« in size. In the tentacles they reach a size of 36 — 41 X 2,5 ^ ^ 1 ^ andinthe actinopharynx 29 — 36(38) x about 3/1. I have in the actino- pharynx also observed some nematocysts with discernible basal part to the spiral thread. They are 26 — 29 X 5 // in size. The spirocysts of the tentacles vary from 24 X 2 a to 62 X 4 ji. The arrangement of the mesenteries mostly agrees with that of specimen 4 of 5. tuberculata. A schematic figure of the arrange- ment of the stronger mesenteries I have given in textfig. 203. The agroupment of the mesenteries in both the uppermost sextants does not completely correspond with that of 5. tuberculata nor with that of the middle sextants. The perfect pairs are, however, 16, three pairs consist of one imperfect and one perfect mesentery. Both mesenteries of the imperfect pairs do not differ so much in size as the former species. I have been able to determine with certainty the position of the mesenteries of the first cycle (on the figure designated with I). The four lateral pairs of mesenteries were namely at the base united with each other, two and two (on the figure designated with spaced-out lines) , while all other mesenteries, excepting the directives, do not reach so far towards the centre of the pedal disc. The 10 pairs of the second order (II) show the same expansion on the pedal disc as in 5. tuberculata. The muscles of the mesenteries recall those of the same species, though they are weaker, this is possibly connected with an individual variation, which I cannot decide as I have had only one specimen for examination. The fertile pairs of mesenteries, alternating with the 34 sterile and filament-bearing pairs, were developed only in the proximal part of the body and pro- vided with rather few ova; they were, as in S. tuberculata., devoid of filaments. Textfig. 203. Sicyonis Diagram of the arrangement of the sterile mesenteries. Sicyonis variabilis n. sp. PI. 3. Fig. II. Diagnosis: Body in contracted state more broad than high. Sphincter weak, reticular. Tentacles about 70 (67 — 74) in number, with a thick mesogloea which does not form any basal swellings at the base, cylindrical to conical, in contracted state with irregular, transversal furrows. Longitudinal muscles of the tentacles on the outer and the inner side, at the base, equally developed. Radial muscles of the oral disc in- terrupted at the insertions of the mesenteries. Actinopharynx ordinarily long. Pairs of mesenteries variable, unto about 100 or a little more. A variable number of perfect pairs (to 21) and a smaller number of pairs, in which one mesentery is perfect, the other not. The arrangement of the mesenteries very variable, unequally developed on both sides of the directive plane. The folds of the longitudinal muscles of the mesenteries as ACTINIARIA 219 in 5. tuberculata but not as high. ParietobasUar and basilar muscles and stomata as in S. tubo'cidata. Nema- tocysts of the tentacles as well as those of the actinopharynx very numerous, the former 31 — 38 X 2,5 ft., the latter 19 — 29 x 2 (2,5) ft. Spirocysts of the tentacles very numerous, from 24 X 2 ;/ to 58 X 4 /a. Colour in alcohol: uncoloured, actinopharynx brown. Dimensions of the largest specimen: Breadth of the pedal disc 4,5 X 3,5 cm, height of the body about 2,6 cm, length of the inner tentacles 1,4 cm, that of the outer 0,5 cm. The smallest specimen was i cm high and 2,2 X 1,5 cm broad. Occurrence: 6o°37' N. 27°52' W. 799 fms. Bottom temp. 4,5° (Ingolf-Exp. St. 78) g specimens. Exterior aspect: The pedal disc is well developed, in contraction wrinkled. The column is like that of the species, described above, sometimes there seems to be an indication of a margin and a fossa, it is, however, probable, that they have arisen by contraction, as in one and the same individual such formations appear in some parts, and are wanting in other parts. The tentacles are from cylindrical to conical, according to the different state of contraction, in contracted state provided with irregular, transverse furrows and devoid of abaxial thickenings at the base. The inner tentacles are at least twice as long and broad as the outer. They are arranged in several cycles, but the agroupment is difficult to decide. The number of the tentacles was in the largest specimen 71, in the smallest 74, and in a third 67. The tentacles occupy the greater part of the oral disc which is provided with distinct, radial furrows. The actinopharynx is longitudinally sulcated, on account of the bad preser\^ation I cannot determine the number of furrows. The siphonoglyphes are distinct and provided mth aboral prolongations. Anatomical description: To judge from the small remaining fragments the ectoderm of the column is low and contains rather numerous nematocysts, about 17 X 2 /^ in size. The mesogloea is very thick, fibrillar, with scattered, protoplasma-poor cells. The sphincter is weak, takes up about one third of the breadth of the mesogloea and shows a decidedly reticular structure as in Stomphia coccinea. The column, however, seems to be able to cover tentacles, as they were indiscernible in one specimen. The endodermal circular muscles are weak and form low folds. The ectoderm of the tentacles is not particularly thick and contains very numerous nematocysts, 31 — 38 X 2,5 11 in size, and spirocysts from 24 X 2 // to 58 X 4 ;u. The mesogloeal longitudinal muscles are strong and uniformly developed round about the tentacles and also at the base. The muscle meshes are often elongated in radial direction. The mesogloea is thick. On a long- itudinal section (textfig. 204) through the apex of a tentacle the mesogloea was much thinned out about the aperture. If this thin lamella has been torn up by bad preservation, we may easily fancy that the apertures of the tentacles were large. There is no doubt that the large apertures, observed by Hertwig in the tentacles of Sicyonis crassa, have arisen through the at the apex very thin mesogloea having been partly macerated by preservation. The radial muscles of the oral disc are very well developed and form closely packed meshes, elongated in the direction from the ectoderm to the endoderm, and interrupted by thick mesogloea-bridges at the insertions of the mesenteries. Its mesogloea is thick, like that of the actinopharynx. The ectoderm of the actinopharj'nx is rather low, especially in comparison with the mesogloea, and contains very numerous nematocysts: 19 — 29 X 2- — (2,5) /i in size, I have besides observed some larger nematocj'sts (34 — 36 X 2,5 fi), which, however, possibly belong to the tentacles. 28* 220 ACTINIARIA Fig. 204 Fig. 205 Textfigs. 204 — 205. Sicyonis variabilis. Fig. 204: Longitudinal section of the apex of tentacles. Fig. 205 : Transverse section of the base of a mesentery with basilar muscles. The arrangement of the mesenteries recalls that of S. ingolfi and tuherculata but is more irregular. In order to ascertain it, I have examined one whole spec- imen and half two specimens. The textfigure 206 .-1 , B shows the arrangement of the mesenteries, each in one half of two specimens, the textfigure 207 that of the third specimen. In A and B all mesenteries have been drawn, in textfigure 207 the fertile have been left out. In the textfigure 206 ^4 the most weakly drawn mesenteries are not provided with longitudinal pennons and re- productive organs, but are certainly future, fertile me- senteries, though the reproductive organs have not yet been developed, owing to the small size of the spec- imen (the height i cm, breadth 2,2 X 1,5 cm). These mesenteries appear only in the most proximal part of the body. I think that I have also in this species been able to determine the mesenteries of the first cycle (I). If we examine the textfigures more narrowly, we find that there are in A (in one half of the specimen) 26 stronger pairs of mesenteries, of which 7 pairs perfect and 2 pairs consisting of one imperfect and one perfect mesentery, in B 23 sterile mesenteries, of which 11 pairs perfect and 4 pairs built up of imperfect and one perfect mesentery (on the other, not drawn half 10 pairs were perfect and 2 pairs made up of one imperfect and one perfect mesentery). In C (fig. 207) we see on one side 21 pairs of sterile mesenteries, of which 9 perfect and 4 made up of one imperfect and one perfect mesentery, on the other side 24 pair, of which 8 perfect and 5 pairs consisting of one perfect and one imperfect mesentery. The arrangement of the mesenteries thus displays great differences, and the mesenteries are not symmetrically grouped on both sides of the directives (compare B, C). Manifestly, a still greater alteration in the time of appear- ance of the pairs of the cycles has taken place here than in the other species, whereby some pairs of mesenteries have been checked in their development or wholly suppressed. The per- fect pairs of mesenteries are among themselves a little un- equally developed, which is seen by their insertion on the pedal disc (on the figure 207 designat- „ ^^ ^ ^. . ^.,. / o Textfigs. 206 — 207. Sicyonis variabilis. ed with spaced out lines) . Also Diagram of the arrangement of the mesenteries. In fig. 207 only the sterile mesenteries have been drawn. ACTINIARIA 221 in the weaker of the sterile pairs both mesenteries of one and the same pair sometimes are distinctly different in size. This is probably in reality still more commonly the fact than may be concluded from the figure, as an attempt of ascertaining their size meets with the same difficulties here as in S. ttiberculata. The arrangement of the mesenteries thus is distinguished from that of the preceding species by its being more irregular, and this irregularity probably (at least in some cases) appearing in all 6 primary exocoels, not onlj- in 4 as in S. tuberculata and ingolfi. Alternating with the sterile mesenteries there are weaker, fertile mesenteries (on figure 207 not drawn, on the figure A , reproduced specimen, the reproductive organs (in the weakest mesenteries) have not yet been developed). These fertile mesenteries also here arise at the limbus of the pedal disc and grow more or less upwards, they are the least developed in specimen A, the most in specimen B, in which they reach the region of the actinopharynx. The longitudinal muscles of the stronger mesenteries form no pennons, but are about equally expanded over the whole surface of the mesenteries. The folds are rather numerous and of ordinary height, they are weakest at the column. On the directive pairs, the folds of wkich are stronger, the innermost part displays the liighest folds. The parietobasilar muscles are in their lower part broad, but rapidly narrowing and proceed upwards as a thin lamella, but do not reach the spliincter. They are not, or somewhat, folded as in the preced- ing species. The basilar muscles are rather well developed (textfig. 205), though not strong, as they are sup- ported by a thick mesogloea. Oral and marginal stomata are present. Whether the latter, which are often very small, are present on all mesenteries, I have not been able to determine. The ciliated streaks are well developed, and the filaments in the region of the ciliated streaks strong. The sterile mesenteries bear filaments, the fertile are devoid of such. The species is dioecious. Genus Actinostola Verr. Diagnosis. Paractiidae (ActinostoUnae) with the body either short, cup-like, in the proximal part small, in the distal broad, or long cylindrical. Column mostly thick, firm, slightly rugose or almost smooth or with flat tubercles of mesogloeal thickenings, unlobed in the distal part, without verrucae, acrorhagi and fossa. Sphincter in comparison to the size of the body usually rather weak, so that the body-wall, at the con- traction of the animal, for the greater part cannot cover the tentacles. Tentacles short, the inner consider- ably longer than the outer, about as numerous as the mesenteries, hexamerously arranged, in contracted state almost cylindrical, irregularly rugose, sometimes with mesogloeal thickenings at the base of the outside, with mesogloeal longitudinal muscles. Radial muscles of the oral disc mesogloeal. Two well developed siphono- glyphes. Numerous perfect mesenteries, hexamerously arranged. The two mesenteries in one and the same pair, from the third or the fourth cycle, irregularly developed but as a rule outlined, so that the mesentery, which generally turns its longitudinal muscles towards the preceding cycle of mesenteries, is more developed than its partner. Retractor of the mesenteries diffuse. Parietobasilar and basilar muscles strong. Mesenteries of the first and the second order sterile. Reproductive organs first arise on the mesenteries of the third cycle. The fertile mesenteries have filaments. ACTINIARIA 222 Actinostola spetsbergensis Carlgr. PI. 2. Figs. 3—4. PI. 3. Fig,s. 13—15. Actinostola spetsbergensis n. sp. Carlgren 1893. PI. i fig. 15. PI. 8 figs. 9, 10. PI. 9 fig. i. — Carlgr. Kwietniewski 1898 p. 130. Carlgren 1902 p. 46, 1913 p. i, 1916 p. 3. — sibirica n. sp. Carlgren 1901 p. 481. 1893 b p. 233 fig. i. — walteri n. sp. Kwietniewski 1898 p. 130. PI. 14 figs. 4 — 6. PKyathactis hyalina n. gen. n. sp. Danielssen 1890. PI. i fig. 3. PI. 7 figs. 6—9. Diagnosis: Pedal disc from wide to small. Body generally in contracted state more broad than high, in expanded state cup-like, in contracted more cylindrical. Column longitudinally furrowed, especially in younger specimens, sometimes also with transversal furrows, so that tubercle-shaped elevations arise, sometimes more irregularly wrinkled. Margin rather distinct, capable of involution. Sphincter strongly reticular, sometimes with a little tendency to become alveolar, seldom with traces of stratification. Tentacles hexamerously arranged, in larger specimens about 130 — 170 in number, the inner considerably longer than the more or less papilliform outer, without thickenings of the mesogloea on the base of the outside; in young specimens smooth, in older, in contracted state, wrinkled or sometimes feebly longitudinally sulcated. Longi- tudinal muscles of the tentacles and radial muscles of the oral disc expanded over only a part of the meso- gloea, and divided in rather fine meshes. Pairs of mesenteries in 5 cycles, the last cycle more or less perfect. Mesenteries of the three first cycles perfect, sometimes only some of the mesenteries of the third cycle are perfect. Mesenteries of the third cycle of different size in every pair, with the longitudinal muscles of the stronger mesen- teries generally directed towards the mesenteries of the first cycle. Parietobasilar muscles very strong. Dioecious. Reproductive organs developed from the mesenteries of the third cycle. Tjqjical nematocysts in the distal part of the tentacles 19 — 31 X 1,5 — 2,5 (3) [i, in the actinopharynx 22 — 31 X 2 — 2,5 (3) fi. Spirocysts in the distal part of the tentacles from 17 X 1,5 n to about 65 (70) X 4 (5) //. Nematocysts with discernible basal part to the spiral thread in the actinophar>'nx 22 — 32 X 4 — 5 [x. Often also large stinging capsules in the tentacles, in their distal part from 36 to 50 X 6 — 7 /x. Colour: pale reddish-yellow (Michael Sars-Exp. St. 96) ; pale reddish (Sw. Spitzberg-Exp. 1898). Ten- tacles pale red (Sw. Spitzberg-Exp. Bremer Sound). Kyathactis hyalina: pale rosy-red, the pedal margin yellowish-red, round the mouth a yellowish-red annulus. The tentacles of a somewhat darker rose-colour than the body (Danielssen). Dimensions: Large specimens unto 2,5 — 3cm high and 6 — 7cm broad, in contracted state. Occurrence: New Foundland Bank. 45°53' N. 5i°56' W. 5ofms. (IngegerdandGladan-Exp. 1871). Rice Strait. 78°45'7 N. 74°56'5 W. 8 fms. (Fram-Exp. 1899). Hafne fiord between 76°25'— 76=40' N and 84=20' W.— 84=45' W. 2—30 fms. (Fram-Exp. 1900). Gaasefiord 76=44' N. 88=45' W. (Fram-Exp. 1901). North-Greenland. Tliule Havn (1914 P. Freuchen). West-Greenland. Upernivik (Ryder). Nordre Stromfiord 225 — 230 m. Bottom temp. — 0,5= (Nordmann 1911 St. 3 A). Nordre Stromfiord 14— 38m. 400 — 410m. (Nordmanni9iiSt.3B,4A). Akudlek(Traustedt).Hol- ACTINIARIA 223 stensborg (Traustedt 1892). Godthaab 100 fms. (Ammondsen). Davis strait 66°45' N. 59°3o' W. (Sofia-Exp. 1883). Davis strait (Holm). 69°i7'N.52°5o'W.225fms. (Tjalfe-Exp. i9o8St. 117— 118). 66°44'N. 56°o8'W. 175 fms. (Tjalfe-Exp. 1908 St. 100). 66°35' N. 55°54' W. 88 fms. Bottom temp. 1,6° (Ingolf-Exp. St. 31). 65°i7' N. 54°i7' W. 55 fms. (Ingolf-Exp. St. 34). Bredefiord 170 — 140 m (Rink-Exp. 1912 .St. 156) no — 180 m (Rink-Exp. 1912 St. 91). Greenland without distinct locality (Wandel 1890). East-Greenland. Mackenzie bay 12 — 35 m (Kolthoff-Exp. 1900). Franz Joseph fiord between Bontekoe Isl. and Mackenzie bay 250 m (Kolthoff- Exp. 1900). The sound between Maatten and Renskaer 25 — 50 fms. (Danraark-Exp. 1908 St. 95). Danmark strait 66°42' N. 26°4o' W. 590 m. Temp, at 550 m 0,11° (Michael Sars-Exp. 1900 St. 13). N. W. of Iceland. 66° N. ii°4i' W. 280 m (Thor-Exp. 1903 St. 52). Iceland 5 miles o from Seydysfiord 135 fms. (Wandel 1890). West Spitzbergen. 8o°N. T.y°s' E. 40 fms. (Sw. Spitzberg-Exp. 1898). 79°io' N. 10° E. (Kolthoff-Exp. 1900). Icefiord,Coal Bay 50 m (Kolthoff-Exp. 1900) Gray Hook 60 fms. (Sw. Spitzberg-Exp. 1861). Recherche bay (Klinckowstrom 1890). East Spitsbergen. North East Land 79°35' N. 28' E. 66 m (Romer & Schaudinn 1898 St. 36). Hinlopen Strait 79°I3' N. 21° E. 80 m (Romer & Schaudinn 1898 St. 44). King Charles Land, Bremer Sound 105 m (Romer & Schaudinn 1898 St. 33), 100 — no m. Bot- tom temp. — 1,45 (Sw. Spitzberg-Exp. 1898 No. 32). Albrecht Bay 13 — 15 fms. (Kiikenthal & Walter). Cap Melcher 45 fms. (Kukenthal & Walter Actinostola walteri), Devee Bay 77°23'N. 2i°2'E. 28 m. (Romer and Schaudinn 1898 St. 8). Bear Island. 140 m (Michael Sars-Exp. 1901). 75°49' N. 24°25' E. 80 m. Bottom temp.— 1,42° (Sw. Spitzberg-Exp. 1898). 75°23'N. I7°45'E. no— 140 m (Olga-Exp. St. 54). 74°48' N. 20°54' E. 80— 86m (Olga-Exp. St. 59). 73 "52' N. I9°55' E. 130—200 m (Olga-Exp. St. 54). 66''42'N. 26°4o' W. 590 m. Bottom temp, at 550 m 0,11° (Michael Sars-Exp. 1900 St. 13). 64°58' N. Ii°i2' W. 550 m. Bottom temp. — 0,32° (Michael Sars-Exp. 1902 St. 36). 64°53' N. io°o' W. 630 m. Temp, at 600 m. — 0,69° (Michael Sars- Exp. 1900 St. 10). Coast of Murnian. no — 120 fms., 70 — 80 fms. (Alex. Kowalewsky-Exp. 1909 St. ^ , ACTINIARIA 224 116, 167 — teste Pax). Pala Guba (teste Pax). Barent Sea 70°2i'3oN. 53°5o' E. 105 m. (Andrej Perwoswanny-Exp. 1903). W. from Kolgujew 69°i4' N. 46°39'30 E. 62 m (Andrej Per- woswanny-Exp. 1903). Kara Sea. 70°9o' N. 64°i7' E. 11 fms. (New-Zembla-Exp. 1875) — (Dijmphna-Exp.). Arctic Sea of Siberia. 20° E. of Cape Jakan 12 fms. (Vega- Exp. No. 60). 69°32' N. i77°4i'W. 12 fms. (Vega-Exp.). 67°7' N. i73°24' W. 9—15 fms. (Vega-Exp. No. 185), 2 miles N. E. of the winter station of the Vega 12 fms. (Vega-Exp. 1879). Behring Sea. 64=34' N. i7i°45' W. 25 fms. (Vega-Exp. No. 1061), 63=39' N. I77°5' W. 55 fms. (Vega-Exp. No. 1068). Exterior aspect: The pedal disc is now rather wide, now of rather small diameter and provided with more or less distinctly conspicuous, radial ridges and furrows, sometimes the central part of it is drawn out in a conical tap as in Stomphia. The form of the body varies considerably, according to the state of con- traction. Now it is cup-like, now more cylindrical, in preserved specimens the breadth generally is larger than the length, it is rarely the opposite. As the oral disc is wholly unfolded, the distal part is broader than the proximal. In small specimens — such which occur in the coelenteric cavity or in the open sea — the column is provided with distinct longitudinal ridges with deep furrows between. Also in larger specimens traces of these ridges are to be seen. They but rarely appear like a folded longitudinal ribbon; often when the ridges arise, there are also transversal furrows which make the animal look as if it were provided with longitudinal rows of tubercles, such as Kwietniewski 1898 has reproduced Actinostola walteri. Sometimes the surface is smooth or irregularly wrinkled. Though no fossa is present, the margin is, however, rather well marked.The region of the sphincter is sometimes thickened and forms a circular wall, in which case the sphincter is strongly concentrated, owing to the contraction. The tentacles are hexamerously arranged in 6 cycles, the last cycle is, however, as far I have seen, always imperfect. The number of tentacles in several large exam- ined specimens varied between 130 and 170. Kwietniewski declares that A. walteri has about 192 tentacles. From his description it seems as if he has not counted them. The inner tentacles are considerably longer than the more or less papilliform outer ones. On very small specimens, as on young in the coelenteric cavity, they are smooth or almost so, on larger specimens they are indistinctly longitudinally furrowed or irregularly wrinkled. They have never any thickenings on the outside of the base. The oral disc is wide, and provided with deep or shallow radial furrows, in contracted state also with circular furrows. The actinopharynx is of ordinary length and longitudinally sulcated, the folds are, however, not as numerous as in the Stomphia- species described below, amounting to about 10 on each side of the directive plane. The gonidial tubercles are distinct, the siphonoglyphes very well marked, broad and provided with long aboral prolongations. Anatomical description: The anatomy of this species has been described by myself 1893 and 1902, and I have but little to add now as my latest examinations have been made on a richer material and mainly verify my former observations. Concerning the stinging capsules, there are in the tentacles typical nematocysts in varying numbers, now numerous, now more sparse, in addition to numerous spirocysts ; in one ACTINIARIA 225 part of the specimens there were large specific nematocysts of the same kind as I have found in the other, below described Actinostola species. These capsules were now numerous, now sparse. I at first supposed that I had to do with two different species, one with large specific nematocysts, the other without such, as there is, however, no difference in their structure I must regard these specimens as belonging to the same species, the more so as I have found some specimens, the nematocysts of which were so sparse that it was only after repeated examinations of the maceration preparations that I was able to find one or a few capsules in the tentacles. I can- not decide the cause of this difference in the occurrence of these ne- matocysts. It may be possible that they have in several cases been lost through preservation, though I must confess that I do not find that explanation satisfactory. In the actinopharynx there are, in addition to typical nematocysts, also some such with discernible basal part to the spiral thread. The size of the nematocysts and the spirocysts in a series of specimens was as follows, a: typical nematocysts, b : large specific, opaque nematocysts, c : nematocysts with discernible basal part to the spiral thread, spi: spirocysts. As wee see, the nematocysts of the dififerent specimens agree well in size, it is therefore probable that the specimens with b-ne- matocysts in their tentacles and those devoid of such belong to the same species. The sphincter also varies a little in appearance. In the type-specimen it was strongly concentrated, in other spec- imens more elongated, as in Stomphia. As we may find a concen- trated as well as an elongated sphincter in different parts of one and the same specimen, I think that this difierence is due to a stronger or weaker contraction of the mesogloea in the distal part of the column. In the type-specimen the spliincter occupies almost the whole breadth of the mesogloea, which was also the case in se- veral examined specimens. In other specimens the part of the me- sogloea, outside of the sphincter, was considerably tliicker, this is especially the case in specimens having a tliick mesogloea. Tliis dif- ference is jDrobably also connected with the more or less strong con- traction of the mesogloea. The sphincter also varies a little in structure. Generally the spliincter is reticular, sometimes, especially in the outermost parts, the meshes are more sparse, wherefore the sphincter here shows a tendency to be alveolar. To judge from the The Itigolf-E.xpedilion. V, 9, .a G, O n "i ■«- o J2 " -- 1 ■ ? r f - r^^ I " 51 i '^^1*511 = , 1 X I , « « y. I « ►. ■* to 1 ' n I I J- X S 1 -s X : X o I X I X \0 •£> X X O (^ I 1 xS :X 5 ? r : "I I « t ; .5 ' X : X X ix I XXXXX XXs^-X,;; lllll :il--l.lR x' x" >^ x' ^ ? x" I ^ ? I xxx^ix A i^ o X S» I 00 CO I "■ I V X ^ X V ^ ^ V « X o « X I w "-i ifc w -If "k ^ " « I - I - ^ I X -s -s X ^ X ^ X X f I ii S I i. 1 i I I • ^ i' K § s V > s o a .2, O Q. -^ V M H Z D in « 5 : >6 2 <" 3 t 1 I i = -s 5 ^ H « fc. ^ M < •»; 29 226 ACTINIARIA figure of the sphincter of A.walteri, reproduced by Kwietniewski (1898) — a species to my mind identi- cal with A . spetshergensis — the sphincter seems to be almost alveolar. In sexually ripe specimens I have but rarely found traces of stratification in the middle part ; this stratification is, however, never as distinct as in Adinostola abyssorum and callosa. The mesenteries are arranged as in the type-specimen, which I ha\^e been able to confirm by several examined specimens. The longitudinal muscles of the strongest mesentery in the pairs of the third cycle face towards the mesenteries of the first cycle. In a single specimen, of which I have examined one half, two mesen- teries deviate from this rule, in as nuich as the longitudinal muscles face towards the mesenteries of the second order. The appearance of the mesenteries as for the rest agrees w^th that of the type-specimen. The size of the marginal stomata, however, varies considerably, some- times they are very large as in the reproduced specimen of A . sibirica (Carlgren 1893b p. 233 fig. i), at other times they are small as in the type-specimen. The ciliated streaks were well developed and the meso- gloea of the filaments in the middle part provided with rather numer- ous cells. The reproductive organs start from the mesenteries of the third order ; in a specimen I have, however, found a fertile mesentery of the second order. In a great part of the specimen the ova were large and few, in other parts numerous and smaller. This difference is probably connected with the fact that the reproductive period in the first case had come to its close. I have in several specimens found young in the coelenteric cavity. Sometimes these young reach a considerable size (Carlgren 1893b, 1902 p. 47). The coelenteric cavity thus in this species serves as a brood-room. As I have before mentioned (1902 p. 47) a parasitic Crus- tacean, probably Antheachares diibenii, sometimes appears in the mesenteries. Sometimes a Nemertin, Nemertopsis actinophila Biirger, seems to live symbiotically with this species. From the mouth of a specimen from Coal bay, Spitzbergen such a Nemertin juts out, quite unhurt. Systematic remarks: As is seen by the list of synonyms, I think that Adinostola sibirica Carlgr. and A. walteri Kwietn. are identical with A. spetsbergensis. The few differences I have found between A. sibirica and spetsbergensis do not justify the formation of a new species for sibirica, as the appearance of the sphincter, of the column and of the stomata may vary. The same is the case with A. walteri. Probably Kya- thactis hyalina Dan. is identical with A. spetsbergensis and is only a young of this species; of this I have con- vmced myself by a comparison of a specimen of this species with young of A. spetsbergensis. I reproduce here a transverse section of the sphincter of Kyathactis (fig. 208). Upon all accounts, A', hyalina is an Actino- sto/a-species and nearly related to A . spetsbergensis. Textfig. 208 AcHnoslola (Kyathactis) hyalina. Transverse .section of .sphincter. ACTINIARIA 227 Actinostola callosa Verr. Urticina callosa n. sp. Verrill 1882 p. 224, 315. Actinostola callosa Verr. Verrill 1883 p. 57 PI. 7 fig. 2, 1883 b p. 515, 534. Carlgren 1893 p. 71 PI. i figs. 17, 19. PI. 4 fig. I. PI. 8 fig. 3. PI. 9 figs. 5, 6 textfigures 18, 19. Parker 1900 p. 753 textfig. II. — atrostonia n. sp. Stephenson 191S b p. 118 PI. 14 figs. 5, 7, 8. PI. 15 fig. 7, PI. 16 figs. 11, 12, 16 — 20. PI. 17 figs. I — 4. Diagnosis: Body in contracted state cylindrical or somewhat cup-like, generally much more high than broad. Pedal disc not larger than the breadth of the column, in contracted state often excavated. Column thick, cartilaginous, in younger specimens often smooth or with irregular furrows, in larger specimens with tubercle-shaped, rather flat thickenings of the mesogloea in the upper part or over the whole surface. Margin indefinite, often continuous with the base of the outer tentacles, not capable of involution. Sphincter mode- rately long but narrow, "non-concentrated, distinctly longitudinally stratified, reticular to alveolar. Tentacles hexamerously arranged, in large specimens in 7 cycles, rugose, sometimes with rather large thickenings of the mesogloea at the outside of the base, the inner tentacles several times tliicker and longer than the outer. These thickenings may appear only on the outer tentacles or on all. I^ongitudinal mesogloeal muscles of the tentacles and radial muscles of the oral disc of variable size but mostly alveolar. Both mesenteries in the pairs of the third C3'cle of about the same size. Parietobasilar muscles about two tliirds of the length of the column. Dioecious. Reproductive organs on the mesenteries from the third cycle. Nematocysts in the ectoderm of the column (17) ig — 24(29) X 1,5 — 2 [i, those in the distal part of the tentacles 22 — 36 X 1,5 — 2 /< and those of the actinopharynx 22 — 34 X 2 /x. Spirocysts of the tentacles from 24 X 2 to 72 X 4,5 — 5 {i. Large stinging capsules in the ectoderm of the tentacles very few (36) 43 — 51 X 6 — 8//, scarce nematocysts with discernible basal part to the spiral thread, in the actinopharynx 21 — 26 X 4 — 5 [J.. Colour generally salmon-coloured or orange, all parts often of nearh' the same colour, body- wall almost always pale salmon-coloured or buff, var^'ing to deep salmon-coloured or orange-red with paler tu- bercles, oral disc most often deep salmon-coloured, or generally of the same colour as the body, but of a darker shade, with paler radii, the large lateral lobes of the lip like the disc, but darker, usually salmon-coloured or orange-brown, the large gonidial grooves whitish or pale yellow, tentacles usually plain deep salmon- coloured or orange-brown, with paler striae or reticulations (Verrill). Body-wall salmon-coloured, shading off a little into blue with j-ellow-red furrows. Tentacles and the outer part of the oral disc yellow-red, inner part of the disc like the body-wall. Actinopharynx and the gonidial tubercles reddish-brown, especially the upper margin of the actinopharynx (Carlgren). Actinopharynx and the whole ectoderm reddish-brown in alcohol (Michael Sars-Exp. St. 76). Dimensions: Large specimens often 16 to 18 cm in height, with the expanded disc 20 — 25 cm broad, larger tentacles about 1,5 cm long and 0,5 — 0,6 cm broad (Verrill). The largest specimen, observed by myself from the Ingolf- Expedition (St. 65), in contracted state: the expanded oral disc 13 cm, the strongly contracted bod^'-wall 11,5 cm in height. A specimen from Japan: height 12 cm, breadth 8 cm. 29* 228 ACTINIARIA Occurrence: East coast of N. America from New-Foundland to Cap Fear 50—640 fins, (teste Verrill). Baffin Bay. 7i°34' N. 65°55' W. 306 fms. (Wandel 1880). Davis Strait 66°49' N. 56°28'W. 235 fms. (Wandel 1889). 66°35' N. 56°38' W. 318 fms. Bottom temp. 3,9° (Ingolf-Exp. St. 32). Kvanefiord S. Greenland 420 fms. (Rink-Exp. 1902 St. 5). 6i°33'N. 19° W. 1089 fms. Bottom temp. 3° (Ingolf-Exp. St. 65). 59°28'N. 8°i' W. iioo — 1300 m. Bottom temp, at 1000 m. 8,07° (Michael Sars-Exp. 1902 St. 76). Norway. Finmark Jokel fiord 80 — 100 m. (Nordgaard). Stonnesbottn 40—80 m (Nordgaard). Drontheimfiord. Drobak (Carlgren). Skagerrak. 230 — 430 fms. (Gunhild-Exp.) 140 m (Thor-Exp. 1903 St. 19). Sweden. Kosterfiord 210 m (Arwidsson). 220 — 230 m (Sandberg 1901). Vader- oarne. Gullmaren 40 — 50 m (Carlgren and others.) S. W. coast of Ireland. 5i°36' N. ii°57' W., 5i°35' N. ii°55' W., 5i°27' N. ii°55'W. 540 — 720 fms. (teste Stephenson A. atrostoma). Further distribution: Japan Kinshin S. off Nagasaki (Bock-Exp. 1914). Exterior aspect. The exterior of this species has before been described by Verrill, by myself, and by Stephenson. Some of the specimens I have examined, as those from Davis strait, Kvanefiord and the station 65 (Ingolf-Exp.), were provided with rather strong tubercles over the whole surface of the column, while others were tuberculated only in the upper part of the body-wall. It seems as if the specimens, Uving in deeper waters, are more tuberculated than those, Uving in shoal waters, my material is, however, too small for deciding this with certainty. The appearance of the tentacles also varies, in as much as all tentacles may be devoid of the mesogloeal thickenings at the base of the outside, as in the specimens from Gullmar-fiord, while several specimens, as those from Baffin bay and Skagerrak, have thickenings only on the outer tentacles, and still others — specimens from the Ingolf-Exp. (St. 65), Michael Sars-Exp. (St. 76), Davis Strait and Kosterfiord (220 — 230 m) — are provided with such thickening's on all tentacles. Also in the Ameri- can forms (from Maine bay and Martha's Vineyard) I have observed specimens with and without tentacle tubercles. I must, therefore, regard Stephenson's ^. flifrastoma, in the main proposed on basis of the presence of tentacle tubercles, as identical with A. callosa, as the anatomical characters of atrostoma agree with those of Verrill's species. I will besides add that the specimens, taken during the Michael Sars-Expedition, perfectly resemble A. atrostoma. Thus, to my mind the species shows a distinct tendency to form tentacle tubercles, as it seems, especially in the specimens living in deeper water 1. Anatomical description. The anatomy of this species has before been sufficiently described by myself and by Stephenson, so that it is unnecessary to discuss it here. I will, however, give an account of the size of the nematocysts and spirocysts in some specimens, a: typical nematocysts, h: large specific nematocysts, c: nematocysts with discernible basal part to the spiral thread, spi: spirocysts. ' The new genus, Catadiomene, proposed by Stephenson (1920) for the Actinostola-iorms with sweUings of the mesogloea at the aboral side of the tentacles, thus must be dropped. ACTINIARIA 229 Habitat: GuUmar fiord Ingolf-Exp. St. 65 Michael Sars-Exp. St. 76 . Baffin Bay Maine Bay Riuck-Exp. St. 5 Japan Bohuslan (a little young) Column a Distal part of the tentacles a b spi. actinopharj'nx 19-22 X 2 fl 22-24 >^ 2 17-19(29) X 1,5-2 19-22 X 2 29-34x1.5/* 22-34x1,5-2 24-32 X 2 26-36 X 2 29-36 X 2 27-36X2 26-36 X 2 22-24 X 1.5 36-46x7/4 45-51 X 7-8 43-49x6-7 46-48 X 7 43x7 46-50 X 6-7 50-51x7 29-41 X {5)6 26 X 2 — 60 X 5 /* 26 X 2 72 X 4.5 24 X 2 — 62 X 5 —67x4,5 24x2 — 70x4,5 24 X 2 — 67 X 4-4,5 22 X 2-65 X 4,5-5 25-29x1, 5/« 26-31 X 2 25-29 X 2 24-29X2 22-34 X 2 24-34 X 2 26-31 X 2 24 X 5 yU 22-26X5 21-23X4 22-26X4 22-26X4,5 22-24X4-5 24X5 14-22X3,5 In my description of the species (1893) I have stated that no marginal stomata are present. They may, however, appear, though not regularly. Remarks. As I have above put forth, I regard Stephenson's atrosioma as identical with A. callosa. On the other hand, I have not added Hertwig's Dysactis crassicornis to the list of synonyms. It is true that it is very nearly related to A. callosa, but it has a much stronger sphincter and a thinner colunui than the real A. callosa, which I have ascertained by examining one of the tj^pe-specimens. At present I dare not place these two species together. In contradistinction to Mc. Murrich (1893) and Rees (1913), who tliink that they are identical, I have not added the species from the West coast of North America, described by Mc. Murrich as A. callosa, either. Probably this species is the same as Hertwig's species. That A. cal- losa nevertheless has a large distribution, is proved by its occurrence at Japan. Actinostola abyssorum (Dan.) Carlgr. Bunodes abyssorufii n. sp. Danielssen 1890 PI. 3 fig. 3. PI. 10 figs. 8 — 9. Actinostola abyssorum n. sp. Carlgren 1893 PI. i figs. 5, 10. PI. 8 figs, i, 2, 7, 8, 11. PI. g fig. 4textfigs. 14 — 17. Diagnosis: Pedal disc wide, of about the same breadth as the length of the body. Column thick- waUed with longitudinal and transversal furrows, whereby tubercle-shaped thickenings arise, which are the largest at the middle. Margin as in A. callosa. Sphincter long, but narrow, not concentrated, distinctly stratified, reticular, forming very thin meshes. Tentacles to about 300, hexamerously arranged, conical, irregu- larly wrinkled, with distinct orifice at the apex, not bulbously swoUen at the base, the inner considerably broader and longer than the outer. Longitudinal mesogloeal muscles of the tentacles and the greater part of the mesogloeal meshes of the oral disc are very finely di\aded. Both mesenteries in the pairs of mesenteries of the third cycle of about the same size. Parietobasilar muscles strong, almost reaching the proximal end of the sphincter. Marginal and oral stomata present. Dioecious. Reproductive organs on the mesenteries from the third cycle. Nematocysts of the column 22 — -26 X 1,5 — 2 fi, those of the distal part of the tentacles 32 — 38 X 1,5 ^andthoseof theactinopharynx24 — -31 X 1,5 (2) /i. Spirocysts of the tentacles from 17 X 1,5 /* to 65 X 5 fx. Large stinging capsules in the tentacles very sparse 48 — -53 X 5 — 6 fj., scarce nematocysts with discernible basal part to the spiral thread in the actinopharynx 24 — 27 X 4, 5 /^. Colour. Column white with a mother-of-pearl lustre, shading off into pale reddish or bluish tinges. Tentacles Havana-brown. Oral disc of the same colour as the column, perhaps slightly darker, and from the „^^ ACTINIARIA 230 mouth thin browu stripes radiate towards the tentacles. Oral labiae and actinopharynx dark chestnut- brown (Danielssen). Dimensions in extended state about 25 cm in height and 20 cm in breadth, in contracted 15 resp. 23 cm (Danielssen). Preserved specimen from Alten fiord: Height 6 cm. Diameter of the pedal disc 7 cm, that of the oral disc 6 cm. Length of the inner tentacles 1,5 — 1,75 cm, that of the outer 0,5 cm. Occurrence: 6i°io' N. 6°32' E. 1229 m. Bottom temp. 6,7° (Norw. N. Atlantic-Exp. St. 2 teste Danielssen). Tanafiord 70°47' N. 28°3o' E. 232 m. Bottom temp. 2,8° (Norw. N. Atlantic-Exp. St. 261). Altenfiord 183 m (Jiigerskiold 1890). Remarks: I have now examined a specimen of Danielssen's Bunodes abyssornm (from the station 261) and I am able to confirm that this species is identical with Adinostola abyssornm, described by myself. The structure of the sphincter, of the tentacles and of the oral disc agrees with that of the same organs of A. abyssorum This is also the case with the stinging capsules. Danielssen's description is not good, there are no acontia, no suckers, the sphincter is mesogloeal etc. For a more detailed description compare my paper (1893). A . abyssorum is nearly allied to .4 . callosa, and it is a question whether this species is really not a variety of A. callosa. I have not seen the specimen from the station 2 and cannot decide, whether it belongs to A. abyssornm or to A. callosa. Concerning Adinostola abyssorum Carlgr. (Pax 1915) compare p. 159. Actinostola groenlandica Carlgr. PI. 2. I'ig. 10. Actinostola groenlandica n. sp. Carlgren 1899 p. 33. Diagnosis: Pedal disc well-developed. Column cylindrical, in contracted state much higher than broad, from rugose to almost smooth, sometimes with indistinct longitudinal furrows, without tubercles, ordinarily thick. Margin rather distinct, probably not capable of perfect involution. Sphincter rather strong, reticular, sometimes with a little tendency to become alveolar and a little stratified. Tentacles hexamerously arranged, in 6 or 7 cycles, in contracted state rugose, the inner longer than the outer papiUar ones, without mesogloeal thickenings at the base of the outside. lyongitudinal muscles of the tentacles and especially the radial muscles of the oral disc divided into rather fine meshes. Actinopharynx about half or one third as long as the body-wall. Pairs of mesenteries in 5 or 6 cycle, the last (6th) cycle more or less perfect. Mesenteries of the three first orders perfect. Both mesenteries in the pairs of the third cycle about equally developed. Parietobasilar muscles strong, almost reaching the sphincter. Monoecious. Reproductive organs on the me- senteries from the third to the last or to the last cycles but one. The older mesenteries always with ova, the younger with ova and testes, often both testes and ovaries in the same mesentery. Typical nematocysts in the ectoderm of the tentacles 19 — 27 X 2 — 2,5 /i and those of the actinopharynx 22 — 29 X 2 /n. Spirocysts of the tentacles from 22 X 2 ^ to about 60 X 4,5 /«. Large stinging capsules in the ectoderm of the tentacles 38 — 52 X 6 — 7 fi, nematocysts with discernible basal part to the spiral thread in the actinopharynx 22 — 29 (32) X 4—5 (6) fx. Colour? ACTINIARIA 231 Dimensions in presented state: L,ength of the largest specimen 6,8 cm, breadth of the base about 3,8 cm, the outer tentacles about 0,3 cm long. Occurrence: West Greenland. Ritenbenk 15 — 20 fms. (Oberg). Julianehaab 5 — 10 fms. (Am- mondsen 1865). Davis Strait 6o°4o' N. 55°54' W. 150 fms. (Tjalfe-Exp. 1909). 69°i7' N. 52°5o' W. 225 fms. (Tjalfe-Exp. 1908 St. 117— 118). Greenland without distinct locality. Exterior aspect. The pedal disc is well developed, though not broader than the diameter of the column. The bodj- is in preserved state cyUndrical, in all specimens considerably higher than broad. The column is more or less wrinkled, in one specimen only in the uppermost part, but forms no tubercles. It is comparatively thin, and the insertions of the mesenteries possibly may be seeu in wholly expanded specimens; traces of indistinct longitudinal furrows also in preserved specimens are sometimes visible. The margin is rather well marked. The tentacles are hexamerously arranged in 6 or 7 cycles, of which the latter is imper- fect and lacking in the smaller specimens. The tentacles are in preserved state wrinkled and devoid of basal thickenings, the inner tentacles are considerably thicker than the outer papilliform ones. No specimen had involved tentacles, and it is a question whether the tentacles may be wholly covered by the column, as the sphincter is comparatively weak, in comparison with the size of the specimens. The oral disc is in contracted state of the animal concave, but not as deeply excavated as in Adinostola callosa, aiidpro\nded with radial furrows, corresponding to the insertions of the mesenteries. The mouth is provided with distinct gonidial tu- bercles. The actinopharynx is one half or one third of the length of the colunm and shows longitudinal ridges, amounting to about 10 in its lower part on each side. The siphonoglyphes are very broad and aborally pro- longated. Anatomical description. The ectoderm of the column contains nematocysts, 12 — 19 X 1,5 — 2 /j. in size, and is thin, in comparison to the mesogloea which is of ordinary thickness and less strong than that of A. callosa. It is provided with few protoplasma-poor cells. The endodennal circular muscles of the column are well developed. The sphincter is elongated, reticular, sometimes in several parts with a little tendency to be alveolar; in a specimen I have observed a tendency to stratification not far from the distal end. The sphincter generally much recalls that of Stomphia, though it is less broad. Outside of the sphincter there is a rather thick, sphincter-free part of the mesogloea which, however, does not make out one half of the whole breadth of the mesogloea. The ectoderm of the tentacles is high and contains very numerous spirocysts, from about 22 X 2 to 60 X 4,5 and few nematocysts of typical appearance, from 19 to 27 X 2 — -2,5 /<. There are, besides, also scattered, large specific nematocysts here, from 38 to 52 X 6 — 7 //. Also in this species they vary in number. In one specimen I found onh' a single capsule in the maceration preparations, while in the other specimens they were more numerous, though never common. The mesogloea of the tentacles is tliick and the mesogloeal muscles form rather small but numerous meshes. The mesogloeal radial muscles of the oral disc are reticular, in the outer part of the disc very strong, and interrupted at the insertions of the mesenteries. The ectoderm of the actinopharynx contains sparse, typical nematocysts, 22 — 29 X 2 /t in size, and nemato- cysts with discernible basal part to the spiral thread, 22 — 29 (32) X 4 — 5 (6) /<. 23^ ACtlNlARlA The mesenteries are hexamerously arranged in 5 or 6 cycles. The mesenteries of the three first orders are perfect, though tlaose of the third order do not reach as far down on the actinopharynx as both the first. Both mesenteries in the pairs of the third cycle seem to be about equally developed. From the mesenteries of the fourth cycle the mesenteries are distinctly arranged, according to the Actinostola--rule.The 12 first pairs of mesenteries are sterile like those of the youngest cycle, sometimes also one part of the last cycle but one. The species is monoecious, and testes and ovaries were simultaneously developed. As far as I have observed, the mesenteries of the third cycle always have ovaries, those of the fourth cycle now ovaries, now testes, sometimes both mesenteries of this cycle are only provided with testes, sometimes the strongest mesentery of a pair has ovaries, the weakest testes. The mesenteries of the fifth cycle as a rule form testes. I have, how- ever, found specimens, in which testes are present only in a part of the mesenteries, while the others have ovaries. The testes, when found, were always numerous. Rather often testes and ovaries may be found in the same mesentery. There is thus a great variation in the distribution of the testes and the ovaries, still it seems, as if the ovaries appear on the older, the testes rather on the younger mesenteries. In the textfig. 209 I have reproduced a transversal section of a part of a mesen- tery with ovaries (ov) and testes (t) . The ovaries, as well as the testes were well developed ; in a specimen, one of the largest of the collection, the reproductive organs were absent. The longitudinal muscles of the mesenteries form no pennons but are ordinarily developed, the transversal muscles are distinct and the parietobasilar muscles strong, well marked and almost reach the spliincter. The basilar muscles on transverse sections are of about the same appearance as in A. spetsbergensis, though the muscle lamella are more extended along the sides of the mesenteries than in this species. I have not observed any marginal stomata; on the other hand, there are commonly oral stomata. I have found small young in the coelenteric cavity of two specimens, in the one specimen they were very numerous. In this respect the species agrees with A. spetsbergensis. Te.Ktfig. 209. Actinostola grocnlandica. Transverse section of part of a mesentery with ovaries and testes. Genus Stomphia Gosse. Diagnosis: Paractiidae (Actinostohnae) with well developed basal disc and rather thin to thick, in contracted state rugose bodj'-wall, which is devoid of tubercles, verrucae, acrorhagi, and fossa. Sphincter strong, so that the body-wall may cover the tentacles. Tentacles short, conical, in contracted state wrinkled or longitudinally sulcated, always without thickenings on the outer side, and like the mesenteries arranged after the number 6 -f 10 (12) + 16 (18). Inner tentacles longer than outer. Longitudinal muscles of the tentacles and radial muscles of the oral disc mesogloeal. Actinopharynx of ordinary length with two well ACTINIARIA 233 developed siphonoglyphes. 16 to 18 (6 + 6 + 4 (6)) pairs of mesenteries perfect, the last cycle of these latter often consisting of a perfect and an imperfect mesentery. Most mesenteries confined to the proximal part of the body. At least the younger mesenteries developed according to the rule of Actinostola. Parietobasilar and basilar muscles well developed. Perfect mesenteries generally sterile; when the perfect pairs are more than 16, the exceeding pairs are often fertile, the weaker mesenteries of the third cycle also often fertile. At least the stronger imperfect mesenteries fertile. The fertile mesenteries have filaments. The genus Stomphia is on one side nearly related to Actinostola, on the other side it recalls Sicyonis in several characters. The j-ounger mesenteries are f. inst. developed as in Actinostola, while in Sicyonis the Actinostola-Tule does not distinctly appear. P'urthermore, several cycles of mesenteries have reproductive organs in Stomphia as well as in Actinostola, wliile in Sicyonis only the last cycle is fertile. The fertile mesen- teries are provided with filaments in Stomphia and Actinostola, but as a rule not in Sicyonis. Stomphia agrees with Sicyonis in the mesenteries being more richly developed in the proximal than in the distal part, and in the double number of mesenteries of the second cycle in four (or six ?) exocoels or, with another interpreta- tion, in the rapid growth of the mesenteries of the third order in certain exocoels (compare p. 216). The mesogloea of the column is generally thinner in Stomphia than in both the other genera, though also in Acti- nostola spetsbergensis, especially in young specimens, the column may be rather thin. On the other hand the body- wall is sometimes thickened in Stomphia (compare below). A peculiarity, often displayed by the Stom- phia-species in contracted state, is this that the central part of the pedal disc is extended tap-like. Sometimes the pedal disc of Actinostola spetsbergensis has the same peculiar appearance. To the genus Stomphia the following species certainly belong : the type-species, St. coccinea (O. F. Miill.), St. polaris (Dan.) and St. vinosa (Mc. Murr.) Verr. Concerning the last species, which Mc. Murrich has described as Paractis vinosa, Verrill (1899 p. 295) has put forth that it is a Stomphia, which opinion I fully share. It is true, that Mc. Murrich does not mention more than 32 mesenteries (32 pairs compare Verrill 1. c), but the broad pedal disc indicates that in this part there have been more mesenteries, which Mc. Murrich has not observed. Verrill supposes that also Cymbactis faeculenta Mc. Murr. is a Stomphia. To judge from Mc. Murrich's description, this is certainly not the case. Mc. Murrich namely says that this species is provided with about 96 tentacles but not more than 24 pairs of mesenteries. Evidently there has been one more cycle of mesenteries developed in the distal part, — as in the Actiniaria the number of tentacles is not greater than that of the mesenteries — which Mc. Murrich has not observed. The mesenteries is therefore here probably more numerous in the distal than in the proximal part, while it is just the other way in Stomphia. On the other hand, it is very probable that Cymbactis selaginella, described by Stephenson 1918, is a Stomphia, though the body-wall is considerably thickened here. The whole organisation and the exterior of this species as well asStephenson's^ information that "a curious little imperforate mound arises from the concave centre of the basal disc" speak for this opinion. Such a "mound" is, as I have stated above, characteristic of Stomphia. Further the presence of "small single mesenteries" in the proximal part recalls Stomphia. Thus I think that Cymbactis selaginella is a Stomphia-species. Verrill (1899 p. 217) declares that large specimens of Stomphia carneola = St. churchiae = 5^ 1 Compare p. 211. The Ingolf-Expedition. V. 9. 30 ACTINIARIA 234 coccinea, have 24 pairs or more perfect and that all the perfect mesenteries are fertile. Neither Mc. Murrich (1911 p. 79) nor I m3'self have found this to be the case. Verrill either hinges his statement on erroneous observ^ations, or — which is more probable — Verrill has confounded another Paractid with Stomphia (compare further 5^. coccinea^). For this reason I have not encluded Verrill's statement in the diagnosis. Stomphia coccinea (O. F. Miill.) Carlgr. PI. 2. Figs. I. 8. Actinia coccinea n. sp. O. F. Mtiller 1776 p. 231, 1778 2. d. 30 figs, i — 3. — • — Miill. Gmelin 1788 — 93 p. 3133. Bruguiere 1789 n. 5 PI. 72 figs, i, 2. Blainville 1830 p. 290, 1834 p. 324. lyamarck 1837 3. p. 540. 0rsted 1844 p. 72, 74. Johnston 1847 p. 215. Sars 1851 p. 144. Danielssen 1859 p. 45 (p. p.). Milne-Edwards 1857 — 60 p. 243. v. Beneden 1866 p. 189 PI. 19 figs, i — 4. Stomphia coccinea (O. F. Miiller) Carlgren 1893 p. 138, 1902 p. 47, 1913 p. 4. Lonnberg 1898 p. 55. Mc. Murrich 1911 jj. 47. Stomphia churchiae n. sp. Gosse 1859 p. 48, i860 p. 222 PI. 8 fig. 5. Norman 1868 p. 440, 1869 p. 318, Schulze 1875 p. 140, Andres 1883 p. 369. Mc. Intosh 1884 p. 53. Pennington 1885 p. 173. Carlgren 1893 p. 80 PI. i figs. 11, 12, PI. 8 figs. 4 — 6, PI. 9 figs. 2, 3, PI. 10 fig. 4 textfig. 22 — 25. Stephenson 1918 b p. 126. Actinia virginea sp. n. Miiller 1778 PI. 6 fig. 53. — carneola sp. n. Stimpson 1852 p. 7. Stomphia carneola (Stimps.) (p. p.) Verrill 1899 p. 206. Parker 1900 p. 753. Actinia nitida sp. n. Dawson 1858 p. 404 figs. 3 — 5. Rhodactinia davisii var. 4 Verrill 1864 p. 19, 20. KyUndrosactis elegans sp. n. Danielssen 1890 p. 4, PI. 2 fig. 8, PI. 8 figs. 4, 5, PI. 9 figs. 5 — 7. Sagartia repens sp. n. Danielssen 1890 p. 45, PI. i figs. 7, 8, PI. 8 figs. 2, 3. Diagnosis: Pedal disc ver>' wide. Column smooth or in contracted state wrinkled. Margin rather distinct. Sphincter strong, long, reticular, sometimes with a tendency to stratification. Tentacles to about 80 in number. Actinopharynx well developed with longitudinal furrows, in number almost corresponding with those of the perfect mesenteries. Mesenteries much more numerous than tentacles. 16 to 18 pairs perfect, sometimes a few of these mesenteries consisting of a perfect and of an imperfect mesentery. Imperfect pairs in variable numbers, in larger specimens in 4 C3'cles, sometimes a tendency to development of a fifth cycle in some exocoels. The last cycle often represented by a single mesentery instead of a pair. I/ongitudinal muscles most developed in the outer part of the mesenteries. Parietobasilar muscles strong, reaching to the sphincter. No marginal stomata (always?). Typical nematocysts in the ectoderm of the tentacles 17 — 26x1,5 — 2,5 fi, in the actinopharynx 19 — 27 X 2 — 2,5 fj,, spirocysts of the tentacles from 19 X 1,5 /* to 60 X 4,5 — 5 fi. Besides large specific nematocysts, 34 — 55 x 5 — 7 ju in size, in the tentacles, nematocysts with discernible basal part to the spiral thread, 22 — 26 x 3,5 — 5 /< in size, in the actinopharynx. Colour variable. Column cream-white, pale pink or flesh-coloured, irregularly marked with carmine. ACTINIARIA 235 rose-red or scarlet, of a darker shade on the margin (sometimes the whole surface flesh-coloured or pale greenish- white, Verrill). Tentacles translucent pale pink or flesh-coloured with two circular bands of orange-red, rose-red or carmine and the tips of the same colour. Oral disc white, j-ellowish-white, cream-coloured, greenish- white or pale orange-red with opaque white spots at the base of the inner tentacles. Mouth surrounded by a narrow circle of rose-red, scarlet or orange-red {coccinea, Churchiae, carneola, Gosse, Carlgren, Verrill, Mc. Murrich). Column milky white, strongly opalescent. Oral disc pale brownish-yellow with darker coloured, radial rows, the narrow circle of the actinostome brownish-red. Inner tentacles brownish-yellow with darker bases, outer tentacles paler with reddish tips [Kylindrosactis Danielssen). Column milky white with a lustre of an exceedingly faint violet tinge. Oral disc pale buff colour. Tentacles a little darker than the disc [Sagartia rcpens Danielssen). Dimensions. Diameter of the pedal disc unto 6,5 cm, height of the column unto 5,5 cm in pre- served state. Occurrence: Arctic coast of N. America to Cape Cod (teste Parker). L,abrador (teste Packard). New Foundland Banks 45°59' N. 5i°49'W.; 46°5' N. 5i°4i'W.; 46°6'N. 52°3' W. 46 fms. (Ingegerd & Gladan-Exp.). New Foundland (Verkriizen). Jones Sound (Fram-Exp. 1900 — 1901). West Greenland. Upemivik 130 fms. (Ober'g 1870) (Ryder). Umanak 30—40 fms. (Torell). 7o''29'N. 55°4o' W., 7o°27' N. 55°4o'W. 50—60 fms. (Sofia-Exp. 1863). Disco bay (Rink-Exp.). Ritenbenk 15—20 fms. (Oberg 1870). Jacobshavn 35 fms. (Obergi87o). Claushavn 40 fms. (Obergi870). Ikamiut (Lohmann 1905). Egedesminde 30 — 80 fms. (Oberg 1870) (Traustedt). Davis Strait(Holm),NordfeStr0mfiord 325 — 330 m. Temp, at the bottom — 0,01°. SaUnity 3,7° at + 3° temp. (Nordmanni9ii). Holstensborg (Traustedt 1882), 2ofms. (Holm 1882). 66°45'N. 59°3o' W. 35 fms. (Sofia-Exp. 1883). Godthaab 64°i9' N. 100 — 200 fms. (Ammondsen 1863). Skinder- hvalen 63=3' N. 40 fms. (Ammondsen 1863). 63°35' N. 52=57' W. (Ingegerd & Gladan-Exp. 1S71). Bredefiord 170—180 m (Rink- Exp. 1912). Julianehaab 6o°4o' N. 60 fms. (Ammondsen 1863). Pectenbanke (Traustedt 1892). Skovfiord 70—140 m (St. 156) 80 — 120 m (St. 152) (Rink-Exp. 1912). Greenland without distinct locality (Traustedt 1892, Oberg and others). Iceland. Berufiord (Torell), Dyrefiord 50 fms. (Lundbeck 1892). N. W. of Talkni 64°05'4N. 22°55' W. 2ofm.s.(Beskytteren-Exp.i9o6). Ofiord (Diana-Exp.1884) West Spitzbergen. Bell Sound 30—40 fms. (Torell 1858). Icefiord Advent Bay 30 — 35 m. Bottom temp. 2—2,7° (Sw. Spitzberg-Exp. 1906 St. y^). 30* 236 ACTINIARIA Green Harbour 140 m. Bottom temp. r,i° (Michael Sars-Exp. 1901). 77°4i'N. i2°5o'E. 95 m (Olga-Exp. St. 18). East Spitzbergen. Edge lyand Devee bay 77°23' N. 2i°2' E. 28 m (Romer & Scliaudinn 1898). Bear Island— Hope Island 75°49' N. 24°25' E. (Sw. Spitsberg-Exp. 1898). Barents Sea. 74°i8' N. 3i°i2' E. 269 m. Bottom temp. — 0,4° (Norw. N. Atlantic- Exp. 1878 St. 275 Sagartia repens). Murman coast. Eveton Eretik Isl. (Walter & Kiikenthal 1889). Kola E. of WaideGuba (Sandeberg-Exp. 1877:9 — 75 fms. (Alexander Kowa- lewsky-Exp. 22 — 30 fms. St. 37 1908; 23 — 35 fms. St. 183 ; 9 — 15 fms. St. 205; 75 fms. St. 218 1909 — teste Pax). Kolapeninsula(Derjugin). Arctic coast of Siberia. 69°32' N. I77°4i' E. (Vega-Exp. 1878). 2 miles north of the winter station of the Vega (Vega-Exp. 1879). Behring Sea. 64°3o' N. i7i°45' W. (Vega-Exp. 1879). Norway Finmark. Vadso 20 — 40 fms. (teste Danielssen). Porsanger fiord 70°55' N. 26°ii' E. Bottom temp. 3,5^ 232 m (Norw. N. Atlant.-Exp. Kylindrosactis). Outer part of Kvaenang-fiord, Budder bugt and Gurbluluokta 20 — 50 fms (Aurivillius). Ulfsfiord 250 fms. ,. 0 Karlso 30 — 40 fms. (Malmgren 1864). Tromso 30 — 50 fms. Dons), Bjarko 70 m (Dons). Bredvigbugt 14 — 20 fms. (Bjerkan) Norway. Drontheimfiord Rodberg 25 — 30 fms. (Arvidsson and others), Galgeneset, Gjeitenesetioo m())Gunnerus«) , Storfossen 200 m ; N. W.ofBergen(U d ds t r 6 m) . Bergen Hafvosund (teste Sars). Manger; Manger Vegholmen; LaurkoUen 20 — 30 fms. (Sars). N.W. of Egersund 100 fms. (Swedish fishermens). Jaderen 100 fms. (Olsson). Denmark. Jydske Rev 50 — 150 fms. (Uddstrom). Skagerrak 26^/4 miles N. to W. ^/a W. of Hanstholni 120 m (Thor-Exp. 1907 St. 1080). Sweden. Vaderoarne Lophohelia reef, Gullmarfiord: S. of lyoken 15 fms. (Carlgren). Smedjebrotten, Groto; S. of Spattasbadar 20 — 35 m (Zool. St.). N. of Vinga light 42 — 16 m (Lagerberg). Varberg (Cleve). The Sound. EUekilde 15 fms. (Kramp). Aalsgaarde 10 — 15 fms. (Kramp). Helle- baek 24 fms. (Mortensen, Jungersen). S. S. W. of the light of Hal- lands Vadero 15 fms. (I^onnberg). Between Arild and Torekow 14 fms. (I/onnberg). Helsingborgi3 — 22fms. (Gunluld-Exp.). Between Helsing- borg and Landskrona (Rhamn). Landskrona (Orsted, Gunhild-Exp.). S. V. of Knakaken 29 m (I^onnberg). N. of Hven 14 fms. (Kramp). Great Belt. S. E. of Knuds Hoved (Mortensen). ACTINIARIA 237 Further distribution. The North Sea, British Islets, Shetland Isl. Exterior aspect. The exterior of this species has been described before by various authors, where- fore further discussion of it is unnecessary. In some specimens the column is rather thick in preserved state. Concerning the pedal disc (compare p. 233). Anatomical description: The anatomy of this species has also been described by myself (1893), by Verrill (1899) and by Mc. Murrich (1911). Mc. Murrich's account of the organisation agrees with mine, except in some small details; on the other hand, Verrill's account differs from mine in some important characters, as I have mentioned above. On some points I will, however, complete my earlier observations. Concerning tlie stinging capsules, there are in the tentacles two kinds of nematocysts, partly typical rib-like, smaller ones (a), partly larger, broader in the basal end, and sometimes provided with discernible basal part to the spiral thread {b). In the actinopharynx we also find two kinds of nematocysts, partly typical (a), partly with discernible basal part to the spiral thread (c) . In the distal part of the tentacles the largest nema- tocysts are found. Eight more closely examined specimens show a good agreement in the size of the stinging capsules, as shown by the following list. Habitat Distal part of the tentacles b spi. Pro.xiiiial part of the tentacles " a b " Actinopharynx Disco fiord .... Skov fiord .... Egedesminde . . Locality ? Ikarniut Labrador Dyre fiord .... Bohusliin 23-25 X 2 /* ig X 2 — 26 X 2,5 19-26x2-2,5 20 X 2 — 26 X 2,5 *I9X 1,5 — 24X2 *I9-22 X 1,5 19-22 X 1,5-2 48-5.5x5(6)^ 41-50x5-7 41-50x5-6 41-50x5-6 * 36-53 X 5(6) *36-50X5 38-53X5 19X1,5— 60X4-4,5 yM 22X1,5 60X4-4,5 —55 X 3.5-4 22x2—55x4,5-5 —55 X 3,5 *22X 1,5—50X4,5 22x1,5—48x3,5 19-23x2 tl 17-22 X2 36-46 X 5-6 n 34-46 X 5-6 23-26x2,5 fi 22-25x2,5 19-24X2-2,5 24-27? X2,5 22 X 2 19-22 X 2 24X3.5 II 24X4.5-5 24X5 24X5 24-26X4-5 22-24X4,5 24X5 22-25 X 4-5 The with * designated stinging capsules also contained capsules from the proximal part. The nemato- cysts of the column are small, in an examined specimen their size was 14 — 17 X 1,5 [i. Concerning the mesenteries, I have before (1893) put forth that the youngest mesenteries are developed according to t\\& Actinostola-m\e. This rule also seems to be valid as far as the older mesenteries are concerned, it is especially distinct in the first cycle of imijerfect mesenteries. It is true that these latter seem to be equally developed in transverse sections, but their insertion on the pedal disc shows that both mesenteries of one and the same pair are of different size (textfigure 210). The Actinostola-r\Ae is, however, not so distinct here, because the development of the mesenteries, after the appearance of the 6 first pairs of mesenteries, is not the typical one. Instead of a development of 6 pairs of mesenteries of the second order, common in the Actiniaria, 10 or 12 pairs have arisen which are all or for the greater part perfect, like the mesenteries of the first order. On textfigure 210 we see that two pairs of the second order and 3 pairs of the third order corres- pond to each primary exocoel. Of these latter, which form the first cycle of imperfect mesenteries, the weakest mesenteries in two adjacent pairs are facing each other — to judge from the extension of the mesen- teries on the pedal disc — and stand nearest to the interjacent pairs of the second order (designated with II). 238 ACTINIARIA 111 the third pairs of the third cycle the weakest mesenter>' is facing the second pair of the second cycle (designated with II a, a II). The mesenteries of the third order thus seems to be developed according to the Adinostola- rule. Regarding the insertions of the mesenteries of the second cycle on the pedal disc, we find that also here the Actinostola-mle. is vaUd. The weakest mesentery in each pair namely stands next to the mesenteries of the first order. Thus the Actinostola-rulQ appears earlier here than in the genus Actinostola, where it is only ^ to be distinctly observed from the third cycle. The cause of this difference is that in Stomphia, provided with i8 pairs of perfect mesenteries, the number of pairs of mesenteries of the second cycle probably is doubled (12 instead 6), while in Actinostola the number is the typical 6. It is easy to understand that the mesenteries of the second order in a species with only six pairs of second mesenteries cannot be arranged according to the Actino- stola-rvAe. For that arrangement a reduplication of these mesenteries is first of all required. The specimen of which I have above described and reproduced the arrangement of the mesenteries, was of rather considerable size (the height was about 2,5 cm and the breadth of the pedal disc 6 cm in pre- served state). The number of the tentacles was 74 and the mesenteries consisting of no less than 140 paired and 72 unpaired mesenteries. Also the mesenteries of the fourth cycle and those of the following are arranged Textfig. 210. Stomphia coccinea. Diagram of the arrangement of the mesenteries. The spaced- out lines indicate the extension of the stronger mesenteries on the pedal disc. The fertile mesenteries are provided with groups of points on the inner side. The arrows in the in- terior of the diagram indicate the place of the weaker according to the Actinostola-ru\&, Sometimes a mesen- mesentery in the pairs of the third cycle. ^^^ ^f ^ subsequent cycle is established, before the mesentery of the preceding cycle has got its partner. As this mesentery is developed on the side away from the longitudinal muscles of the hitherto unpaired mesentery of the preceding cycles, the arrangement of the mesenteries seemsapparently tobecontrary tothe^-fdwos^o/a-rule. Two unpaired mesenteries of two different cycles (6 and 7) in such a case are placed beside each other. The greater part of the mesenteries are developed only in the most proximal part of the body at the limbus and mostly appear as small folds without filaments (in the textfigure these mesenteries are marked with stippled lines). Issuing from the one directive pair (i "^ fig. 210) the arrangement of the mesenteries in the more closely examined specimens was as follows. The fertile mesenteries are marked with k; {k) indicates that only the strongest mesentery of the pair is fertile; 0 signifies unpaired mesentery not lia\-ing got its partner. The perfect mesenteries are designated with Roman numerals, the imperfect with common numerals. k k k (k) k (k) (k) k k k k (k) k 1654535456 1165453 5 456 11 65453 5 456 1654535456 11654 0 00 0 0 00 0 0 00 00 00 0 0 ACTINIARIA 239 jfc * (k) k k k (k) k k k (k) k k k 535456 II 7656453 6 54 6 567 176 5 456 3 5456 II 656456 3 6564 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 (k) k k k (k) (k) k k k k k k k 6 5 6 II 6 5 4 5 3 6 5 4 6 5 6 7 17 6 5 4 5 3 5 4 5 6 II 6 5 4 5 6 3 6 5 4 5 6 II 6 5 4 5 0 0000 0000000 * k (k) (k) k k k k k k k k k 365456 165 6 4563654567 II (5 5 4563 6 5 4656 II 5453 6 546567 0 000 00 000 0 u 0 0 (k) k (k) k k (k) k (k) k k k I 6 5 6 4 5 6 3 6 5 4 6 5 6 7 II 6 5 4 5 3 5 4 5 6 II 5 4 5 3 5 4 5 6. 0000000 000000 As we see, the development of the mesenteries is a httle different in the secondary compartments. In certain compartments a seventh cycle of mesenteries is present. The mesenteries of the third order and at least the strongest mesentery of the pairs of the fourth order were always fertile, the reproductive organs more rarely appear in the mesenteries of the fifth order. When the number of perfect pairs of mesenteries exceeds i6, the exceeding mesenteries may be pro- vided with reproductive organs. It also may happen that when certain pairs consist of a perfect and an imperfect mesentery, the former then is sterile, the latter fertile. I have never observed more than iS^/., perfect pairs of mesenteries in this species (Carlgren 1902 p. 49). Verrill's statement that 24 pairs or more sometimes are perfect, I cannot confirm (compare p. 234). Stomphia polaris (Dan.) Carlgr. PI. 2. Fig. 5. Tealiopsis polaris n. sp. Danielssen 1890 p. 45 PI. i figs. 7, 8 PI. 8 figs. 2 — 3. Stomphia polaris (Dan). Carlgren 1902 p. 49. Diagnosis: Pedal disc wide. Column and margin as in St. coccinea. Sphincter reticular, wide. Tentacles more than 80, unto 115. Actinopharynx with about 28 longitudinal ridges, siphonoglyphes with aboral prolongations. Mesenteries more numerous than the tentacles, 16 pairs perfect, of which 4 pairs weaker and often consisting of one perfect and one imperfect mesentery. Imperfect pairs of mesenteries in the region of the actinopharynx in 2 cycles, at the basal disc in 3. Muscles of the mesenteries aljout as in St. coccinea. Nematocysts in the ectoderm of the tentacles (19) 24 — 31 X 2 — 2,5 [i, in the actinopharynx 22 — 30 x 2 — 2,5/*. Spirocysts of the tentacles from 19 X 1,5 [x to 53 X 3,5 — 4,5 //. Large specific stinging capsules in the tentacles not present (or very seldom?). Colour. Encrusted portion of the column whitish-gray, naked portion and also tentacles sometimes pale dirty whitish-yellow with a darker oral disc, sometimes brick-red. The red-coloured tentacles with a darker annulus in the middle, while the extremities are lighter, the whitish-yellow tentacles with a white crescent in the middle of their adoral surface (Danielssen); reddish-yeUow (Romer & Schaudinn). Dimensions of the reproduced specimen: Heigth of the column 2 cm. Diameter of the pedal disc 2,5 cm, that of the column at the base of the tentacles 3 cm. Occurrence: East Spitzbergen. Great Isl. 8o°i5' N. 30°o' E. 95 m (Romer & Schaudinn-Exp. St. 37). Hinlopen Strait. 79°2o' N. 20°55' E. 80 m (Romer & Schaudinn-Exp. St. 15). ACTINIARIA 240 Bismarck Strait. 78°58',5 N. 20°35' E. 35 m (Romer & Schaudinn-Exp. St. 45). Unicorn Bay. 78°4o' N. 2i°3i' E. 60 ni (Romer & Schaudinn-Exp. St. 46). Great fiord, Changing point. 78°I5' N. 20°o' E. 105 — iiom. (Romer & Schaudinn- Exp. St. 6). W. Thymen Strait. 78°i4' N. 2i°45' E. 38 m (Romer & Schaudinn-Exp. St. 47). R3'k-ys-Islets. 77°49' N. 25°i2' E. 60 — 80 m (Romer & Schaudinn-Exp. St. 49). West Spitzbergen. Bell Sound. 30 — 35 fms. (Tor ell). Norway- — Bear Island. 72°53' N. 2i°5i' E. 408 m. Bottom temp. 1,5" (Norw. N. Atlantic-Exp. St. 323). Exterior aspect: The pedal disc is wide and irregularly folded, there are sometimes traces of radial furrows. The middle part is often, as in the anterior species, extended in a tap-like formation. The limbus is well marked. The form of the column varies with the different state of contraction and is now cylindrical, now narrower in the middle part with proximal and distal end broader (PI. 2 fig. 3). The column is in con- tracted state wrinkled and the margin rather well marked. The tentacles are short, cylindrical, pointed at the apex, in contracted state irregvilarly wrinkled or longitudinally sulcated. The inner are considerably thicker and longer than the outer. Already in small specimens the number of tentacles exceeds the maximum of tentacles in 5^ coccinea. The number of tentacles f. inst. was 87 in a specimen, the pedal disc of which was 0,7 cm broad and the column 0,9 cm high. The number of tentacles was commonly between 95 and 115, the latter number in a specimen of which the pedal disc was 0,6 cm and the height of the column 1,4 cm. The tentacles were arranged in 5 cycles, 6 + 10 + 16 + 32 + 64, of which the last was imperfect. The oral disc is wide and provided with radial furrows, corresponding to the insertions of the mesenteries; the furrows appear most distinctly in the outer part of the disc. There are besides indistinct transversal furrows, arisen by contraction. Two distinct gonidial tubercles are present. The siphonoglyphes are broad and aborally prolongated. The actinopharynx is distinctly longitudinally sulcated, on each side of the direction plane about 14 furrows appear. Anatomical description. The ectoderm of the column is rather high and contains few nemato- cysts, about 17 X 1,5 fi large. It forms a cuticle which may be incrusted with foreign bodies, probably kept together by the secretion of the mucus cells. This cuticle, which does not reach any greater thickness, however seems to be easily thrown off, as it is wanting in the specimen reproduced in the figure PI. i). The sphincter is reticidar as in St. coccinea, now shorter now longer, according to the state of contraction. The distribution of the sphincter, the muscles of the tentacles, and those of the oral disc agree with those of the anterior species. The nematocysts in the apex of the tentacles are 24 — 31 X 2 — 2,5 fi in size, in the proximal part a little smaller. The spirocysts vary in size from about 19 X 1,5 /^ to 53 X 3,5 — 4,5 /i. I have not observed any large specific nematocysts in the maceration preparations of the numerous, examined specimens. In a single, small specimen from Changing point I have, however, found such capsules in rather great numbers. Such capsules either very seldom occur, or this specimen is a hybrid coccinea &polaris with the same number of tentacles as in polaris and with large nematocysts as in St. coccinea. The supposition that we here have to do with a hybrid ACTINIARIA 241 is not unlikely, as both species are very nearly related to each other. In the ectoderm of the actinopharynx I have found only tjqDical nematocysts, 22 — 30 X 2 — 2,5 /« in size. The arrangement of the mesenteries agrees very well with that of Si. coccinea, I have, however, not found anj' more than 16 perfect pairs in the five specimens which I have examined more closely. Of these 16 pairs four are weaker than the other pairs and most frequently consist of one perfect and one imperfect mesenterj', the former sterile as the other perfect mesenteries, the latter most often fertile. These weaker mesenteries were placed symmetrically on both sides of the directive plane. If we indicate the mesenteries of the first cycle with I, the stronger perfect mesenteries of the second cycle with 2 and the weaker of the same cycle with 2j, the stronger and always perfect 2j mesenteries with a, the weaker with h, the arrangement of these dm mesenteries on both sides of the directive plane was the following I 2 2i I 2 2^ I 2 (I). In a primary dorso ab a b lateral (?) exocoel thus no 2j-mesenteries are developed. The mesenteries besides follow the Actinosiola-TVile in their development. A specimen, the pedal disc of which was 1,8 cm broad, the height of the column 1,9 cm, and the number of tentacles 95 in the region of the actinopharynx, shows the following arrangement of the mesenteries. 0: unpaired mesentery in this region. dm dni 143424342,3 I43424342i3 14342434 14342434 I 32^4342434 I 4342i4342434. 0 00000 The weakest mesenteries are in the vicinity of 2^. In the most proximal part of this specimen the number of mesenteries was 171. Thus the number of mesenteries, in comparison with that of the tentacles, is much smaller in this species than in St. coccinea. If we take the number of tentacles to be i in both species, the number of mesenteries in the named ^o/an's-specimen is 1,8, in the more explicitly described specimen of St. coccinea 4,76. As for the rest of the organisation it agrees with that of St. coccinea; I have, however, some- times found a small marginal stoma. The longitudinal muscles of the mesenteries vary in appearance, prob- ably according to their different state of contraction, they now recall those of 5^. coccinea (Carlgren 1893), now those of St.(Cymhactis) selaginella (Stephenson 1918a), now they are more expanded over the whole surface of the mesenteries; the longitudinal pennons, commonly provided with higher folds than in St. coccinea, are however limited to the outer part of the mesenteries. The Ingolf-Expedilioii. V. 9. 3' Plate I. Plate I. Fig. I. 2. 3- 4- 5- 6. — 8, 9. — 10. — II. — 12. — 13. 14- — 15- — i6. — 17. i8. — 19- — 20. — 21 — 27. — 28. — 29. — 30. — 31- — 32, 33- — 34. 35- — 36, 37- Eloadis mazelii juv. -/^ a: tentacle, b: part of column. Halcampa? vegae Carlgr. Nat. size. Halcampa ardica Carlgr. not incrusted specimen from Treurenberg bay. ^/j. — — ■ — small specimen from Besimannaja bay. -/j. Edwardsia (Edwardstoides) vitrca (Dan). Proximal part of the type-specimen. */j. Adhelmis intestinalis (Fabr.) Nat. size. — - - ^/i- Paraedwardsia sarsii (Diib. & Kor.) = Edwardsia carnca of Appell5f from Herlofiord. ^I^. Edwardsia finmarchica Carlgr. from Tromso (Kier) type-specimen a little magnified. — vitrea (Dan), from Wijde bay showing heteromorphosis. ^/j. — finmarchica Carlgr. (Goes & Malmgren leg.), ^/j. Limnactinia laevis Carlgr. from Bohuslan. ^j^. Paraedwardsia arcnaria Carlgr. from Skagerrak. ^j^. — — — proximal part seen from the proximal end. 'z^. Sidcractis glacialis Dan. from Sunde much magnified. — — tentacle from the type-specimen magnified. Edwardsia tuberculata Diib. & Kor. from Bergen, ^/j. Peachia hastata Gosse. Series of larvae in different developmental stages, a : from the oral end b : from the side «/i, in fig. 24 the distal end begins to get the form of an octaeder, in fig. 25 the tentacles in beginning development (compare the text). Peachia hastata Gosse from Bohuslan dredged from the clay. 'Z^. — — — from Bohuslan, oral disc and tentacles of the specimen reproduced in fig. 28. «/i- Peachia boekii Dan. & Koren. part of the type-specimen with two tentacles, the conchula and part of the siphonoglyphe. ^Z^. Haliadis arctica Carlgr. from Greenland. ^Zi- Milne-Edwardsia love 11 i Carlgr. from Vaderoarne ^Zi. i" the specimen reproduced in fig. 32 part of the cuticle removed. Halcampoides -purpurea (Stud.) {abyssorum Dan.) small specimen, fig. 34 from the oral side, fig. 35 from the side. ^Zi- Isoedwardsia ingolfi Carlgr. Fig. 36 proximal end *Zi. fig- 37- ^/i- Tlie Tngoli' Expedition A"n. Cailsieu: Acliiilaria L Tab:!. .1 i^^lW 3. / ■ 1^ r 16. £ \^ ^■li'' 6. /^ 22- 2f.O Qb 23. 35. 3>t. 12. cu ^A« i-^". 20. '■: : \^ ?7. ^C<5> ^, J<9. 1>T 3^ rr ./. 5 2^'. V^ '•'3: / -*-•- I'-'- A y w y £imdser>. et Cari^r^n. .i_tJ .\. W Ugrelius & Weslph^il. Stockltulm Plate II. Plate II. Fig. I. Stomphia coccinea (O. F. Miill.). Nat. size. — 2. Cribrina spetsbergensis Carlgr. from Behring Sound. Nat. size. — 3. Actinostola spetsbergensis Carlgr. (= sibirica Carlgr.). Nat. size. — 4. — — — juv. — 5. Stomphia polaris (Dan.). Nat. size. — 6. Anthosactis jan mayeni Dan. from Baffin bay. Tvongitudinal section of the animal. Nat. size. — 7. — — — — Mouth and actinopharynx of the type-specimen. — 8. Stomphia coccinea (O. F. Miill.) pedal disc with conical off-shoot. — 9. Siphonactinopsis laevis Carlgr. Nat. size. — 10. Actinostola groenlandica Carlgr. Nat. size. — II, 12. Halcampoides purpurea Stud. (= H. abyssorum Dan.). Fig. 11. Mesentery seen from the side of the transverse muscles, fig. 12. Mesentery seen from the side of the longitudinal muscles. — 13. Peachia hastata Gosse. Transverse section through part of the aboral prolongation of the sipho- noglyphe showing the strongly ciliated boundary' tract between the peculiar prolongation of the siphonoglyphe and the recurvated part (compare textfig. 132). — 14, 15. Halcampa arctica Carlgr. Longitudinal section of the ciliated and of the intermediate streaks (compare the text p. 122). "llie T-ngolf Ex]:)e(lit.ion V. Carlsreu ; Act iiiia ri;i I . Tab : U. »?«wiS^?=-^^ ^^'rfjT?^^ 2. w^^^,^;v fe H. 9. Ih-. '-0 '\\ Y W \ h -.-cs 73. 15. frv^.-1|Tt^,-^^-;- 1 •. . • i.>"v jjiXMUJ*^''"^^-*'^'^ >'^^ ''"^^llyrv -rrije. l^' HimdsfTL ^Ahlin, d Coa^r^.r Lju'ir A. B. UgrelJus & Westphal, Stocklm: Plate III. Plate III. Fig. I. Sicyonis ingolfi Carlgr. about ^/g. — 2, 3. Sicyonis tuherculata Carlgr. ^/g. — 4, 5- Pycnanthus laevis Carlgr. ^/g. — 6. Phychodactis fatula Appel. — 7. Cribrinopsis similis Carlgr. tom-off tentacles (labelled Zoanthus sp. Kolafiord Derjugin). — 8 — 10. Epiactis (Pseudophellia) arctica (Ver.). Nat. size. — II. Sicyonis variabilis Carlgr. Nat size. — 12. Parasicyonis sarsii Carlgr. (from Michael Sars-Exp. 1902 St. loi). Nat. size. — 13- — 15. Actinostola spetsbergensis Carlgr. (Nordmann St. 3b). Nat. size. llie Tiiooir Expedition \\s. Caxl^ren: Actiniaria I . Tab -. lU. s. 11. iz. i.iv.ir A. IV LJiiiL'im. ^^^ 'A'i;^[|.'ii.n, ?,.iijii! '■'■mxx/ik, rJ, M'nJMson. fihn:. Plate IV. The Ingolf-ExpedJtion. V. 9. -^ Plate IV. ec: ectoderm, me: mesogloea, c: cuticle, in: incrustation. Figs. I — 4. Urticina felina (L) coriacea. I. Part of verruca, maceration preparation. Beale's carmine s: supporting cells, gl.: granulous gland cells. 2. a: supporting cells, b: granulous gland-cells from a verruca, maceration preparation. ■ — 3. Gland cells from the pedal disc, maceration preparation. — 4. a) mucus cells, b) yellowish gland cells from the column outside the verruca. — 5. Halcam-pa arctica Carlgr. Not incrusted specimen. Transverse section through part of the scapus with a papilla, ch: chitinized ectoderm cells? — 6. Scytophorus antarcticus (Pfeff.). Transverse section of part of the scapus. gl: gland cells, cJi: chitin- ized ectoderm cells. — 7. Pamedwardsia sarsii (Diib. & Kor.). Transverse section of part of the scapus with a papilla. ch: chitinized ectoderm cells. — 8. Halcampa duodecimcirrata (M. Sars). Transverse section of part of the scapus with a papilla. ch: chitinized ectoderm cells, gl: gland cells. — 9. Epiactis arctica (Verr.) Transverse section of part of the column with a spot, n: nematocysts, gl: gland cells. Tlie Ingolf B]xpedTtiiiri \'..q. Carl^reiv. Acfiniaria I.Tab: I\'. / If.':- '■»■' 4 », V, 1 I a \ 1^- % 1 \ ?-•! ■; iiy s i. !? v\ ,*. %^ ^'* .fe e ••?w f t 'A J 1 Jf AV .:«.• ->■ y # J^ i?; M ^V y 77?>e 2 \) 6- -i-.'..-, , -^js%^ - r ' tn^ -fic fis^l ?:/,.: 9 772^- — -m£ '\ m.' ■^'&^\ ^'nf^^'%. ^^^/^ 8 « A ? Sf-ec -TJZ£- n r^ir!.jre--i ti^l. gL ch^. Ljustr, A. B. Lagrelius 5: Westphal. Stockholm THE INGOLF-EXPEDITION \ 1 895 — 1 896. THE LOCALITIES, DEPTHS, AND BOTTOMTE/WPERATURES OF THE STATIONS Depth 1 Depth ji Depth Station Nr. Lat. N. Long.W. in Danish fathoms Bottom- 1 temp. Station Nr. Lat. N. Long.W. in Danish fathoms Bottom- temp. 1 Station Nr. Lat. N. Long.W. in Danish fathoms Bottom- temp. I 62° 30' 8° 21' 132 7°2 24 63° 06' 56° 00' 1 199 2°4 45 61° 32' 9° 43' 643 4°i7 2 63° 04' 9° 22' 262 5°3 25 63° 30' 54° 25' 582 .3°3 46 61° 32' 11° 36' 720 2°4o 3 63° 35' 10° 24' 272 o°5 63° 51' 53° 03' 136 47 61° 32' 13° 40' 950 3°23 4 64° 07' 11° 12' 237 2°5 26 63° 57' 52° 41' 34 o°6 48 61° 32' 15° "' 1 150 3°i7 5 64° 40' 12° 09' 155 64° 37' 54° 24' lOQ 49 62° 07' 15° 07' 1 120 2°9I () 63° 43' 14° 34' 90 7°o 27 64° 54' 55° 10' .?93 3°8 50 62° 43' 15° 07' 1020 3°i3 7 63° 13' 15° 41' 600 4°5 28 65° 14' 55° 42' 420 3°5 5' 64° 15' 14° 22' 68 7°32 8 63° 56' 24° 40' 136 6°o 29 65° 34' 54° 31' 68 o°2 52 63° 57' 13° .?2' 420 7°87 9 64° 18' 27° 00' 295 5°8 30 06° 50' 54° 28' 22 i°05 53 63° 15' 15° 07' 795 3°o8 10 64" 24' 28° 50' 788 3°5 31 66° 35' 55° 54' 88 i°6 54 63° 08' 15° 40' 691 3°9 II 64° 34' 31° 12' 1300 i°6 32 66° 35' 56° 38' 318 3°9 55 63° 33' 15° 02' 316 5°9 12 64° 38' 32° 37' 1040 o°3 33 67° 57' 55° 30' 35 o°8 56 64° 00' 15° 09' 68 7°57 13 64° 47' 34° 33' 622 3°o 34 65° 17' 54° 17' 55 57 63° 37' 13° 02' 350 3°4 14 64° 45' 35° 05' 176 4°4 35 65° 16' 55° 05' 362 3°6 58 64° 25' 12° 09' 211 o°8 15 66° 18' 25° 59' 330 -o°75 36 61° 50' 56° 21' 1435 l°5 59 65° 00' 11° 16' 310 -^o°i i<) 65° 43' 26° 58' 250 6° I 37 60° 17' 54° 05' 1715 i°4 60 65° 09' 12° 27' 124 o°9 17 62° 49' 26° 55' 745 3°4 38 59° 12' 51° 05' 1870 l°3 61 65° 03' 13° 06' 55 o°4 18 61° 44' 30° 29' "35 3°o 39 62° 00' 22° 38' 865 2°9 62 63° 18' 19° 12' 72 7°92 19 60° 29' 34° 14' 1566 2°4 40 62° 00' 21° 36' 845 3°3 63 62° 40' 19° 05' 800 4°o 20 58° 20' 40° 48' 1695 l°5 41 61° 39' 17° 10' 1245 2°0 64 62° 06' 19° 00' 1041 3°l 21 58° 01' 44° 45' 1330 2°4 42 61° 41' 10° 17' 625 o°4 65 61° 33' 19° 00' 1089 3°o 22 58° 10' 48° 25' 1845 i°4 43 61° 42' 10° 11' 645 o°o5 66 61° 33' 20° 43' 1128 3°3 23 60° 43' 56° 00' Ouly the PImikloti-Net used 44 61° 42' 9° 36' 545 4°8 67 61° 30' 22° 30' 975 3°o Depth Depth Depth station Xr. Lat. N. Long. W. in Danish fathoms Bottom- temp. Station Nr. Lat. N. Long W, in Danish fathoms Bottom- temp. 1 Station Nr. Lat. N. Long. W. in Danish fathoms Bottom- temp. 68 62° 06' 22° 30' 843 3°4 92 64° 44' 32° 52' 976 i°4 118 68° 27' 8° 20' 1060 — I'o 69 62° 40' 22° 17' 589 3°9 93 64° 24' 35° 14' 767 I°46 119 67° 53' 10° 19' lOIO — i°o 70 63° 09' 22° 05' 134 7°o 94 64° 56' 36° 19' 204 4°I 120 67° 29' 11° 32' 885 — i°o 71 63° 46' 22° 03' 46 65° 31' 30° 45' 213 121 66° 59' 13° 11' 529 -^"1 72 63° 12' 23° 04' 197 6°7 95 65° 14' 30° 39' 752 2°I 122 , 66° 42' 14° 44' 115 i°8 73 62° 58' 23° 28' 486 5°5 96 65° 24' 29° 00' 735 I°2 123 66° 52' 15° 40' 145 2°0 74 62° 17' 24° 36' 695 4°2 97 65° 28' 27° 39' 450 5°5 124 67° 40' 15° 40' 495 ~o°6 61° 57' 25° 35' 761 98 65° 38' 26° 27' 138 5°9 125 68° 08' 16° 02' 729 — o°8 61° 28' 25° 06' 829 99 66° 13' 25° 53' 187 6° I 126 67° 19' 15° 52' 293 ^°5 75 6l° 28' 26° 25' 780 4°3 100 66° 23' 14° 02' 59 o°4 127 66° 33' 20° 05' 44 5°6 76 60° 50' 26° 50' 806 4°i lOI 66° 23' 12° 05' 537 -.>°7 128 66° 50' 20° 02' 194 o°6 11 60° 10' 26° 59' 951 3°6 102 66° 23' 10° 26' 750 -o°9 129 66° 35' 23° 47' 117 6°5 78 60° 37' 27° 52' 799 4°5 103 66° 23' 8° 52' 579 — o°6 130 63° 00' 20° 40' 338 6°55 79 60° 52' 28° 58' 653 4°4 104 66° 23' 7°25' 957 — I°I 131 63° 00' 19° 09' 698 4°7 80 61° 02' 29° 32' 933 4°o 105 65° 34' 7° 31' 762 ~o°8 132 63° 00' 17° 04' 747 4°6 81 61° 44' 27° 00' 485 6° I 106 65° 34' 8° 54' 447 — o°6 ^il 63° 14' 11° 24' 230 2°2 82 61° 55' 27° 28' 824 4°i 65° 29' 8° 40' 466 134 62° 34' 10° 26' 299 4°l 83 62° 25' 28° jo' 912 3°5 107 65° 33' 10° 28' 492 -o^i 135 62° 48' 9° 48' 270 o°4 62° 36' 26° 01' 472 108 65° 30' 12° 00' 97 i°i 136 63° 01' 9° II' 256 4°8 62° 36' 25" 30' 401 109 63° 29' 13° 25' 38 i°5 137 63° 14' 8° 31' 297 — o°6 84 62° 58' 25° 24' 633 4°8 no 66° 44' "°33' 781 — o°8 138 63° 26' 7° 56' 471 — o°6 85 63° ai' 25° 21' 170 III 67° 14' 8° 48' 860 ^.°9 139 63° 36' 7° 30' 702 — o°6 86 65° 03-6 23° 47'« 76 112 67° 57' 6°44' 1267 — i°i 140 63° 29' 6° 57' 780 -o°9 87 65° 02'8 23° 56'» no "3 69° 31' 7° 06' 1309 — i°o 141 63° 22' 6° 58' 679 — o°6 88 64° 58' 24° 25' 76 e'g 114 70° 36' 7° 29' 773 — l°o 142 63° 07' 7° 05' 587 — o°6 89 64° 45' 27° 20' 310 8°4 "5 70° 50' 8° 29' 86 o°i 143 62° 58' 7° 09' 388 -o°4 go 64° 45' 29° 06' 568 4°4 116 70° 05' 8° 26' 371 -o°4 144 62° 49' 7° 12' 276 I°6 91 64° 44' 31° 00' 1236 3° I 117 69° 13' 8° 23' 1003 — i°o T— r= \ 0/ -.0 -,Oa '<.' ■AV^f^^- -< = s * * ^ 5 N "i « Q C C Q a c t ^ "T THE DANISH INGOLF-EXPEDITION. HITHERTO PUBLISHED: 1899. Vol. I, Part I. I. Report of the Voyage by C. F. Wandel (i plate) "j 2. Hydrography by Martin Knudsen (34 plates) . . . j 1900. — Part II. 3. The deposits of the sea-bottom by 0. B. Boeggild j (7 charts) [ 4. Current-bottles by C. F. Wandel (i plate) ) 1899. Vol. II, Part I. The ichthyological results by Chr. Liitken (4 plates) . . 1899. — Part II. On the Appendices genitales (Claspers) in the Green- land Shark, Somniosus microcephalus (Bl. Schn.), and other Selachians by Hector F. E. Jungersen (6 plates) 1900. — Part III. Nudibranchiate Gasteropoda by R. Bergh (5 plates) 1904. — Part IV. The North-European and Greenland lyycodinse by Adolf Severin Jensen (10 plates) 1912. — Part V. Ivamelhbranchiata, Part I, by Ad. S. Jensen (4 plates and 5 figures in the text) 1899. Vol. Ill, Part I. Pycnogonida; by Fr. Meinert (5 plates) 1908. — Part II. Crustacea Malacostraca, I: Decapoda, Euphausiacea, Mysidacea by H. J. Hansen (5 plates) 1913. — Part III. Crustacea Malacostraca, II: Tanaidacea by H. J. Hansen (12 plates) 1915. — Part IV. Copepoda I. Calanoida. Amphascandria by Carl With (8 plates, 422 textfigures) 1916. — Part V. Crustacea Malacostraca, III ; Isopoda by H. J. Hansen (16 plates) 1920. — Part VI. Crustacea Malacostraca, IV : Cumacea and Nebaliacea by H. J. Hansen (4 plates) 1903. Vol. IV, Part I. Echinoidea, Part I, by Th. Mortensen (21 plates) . . . 1907. — Part II. Echinoidea, Part II, by Th. Mortensen (19 plates) . 1914. — Part III. Chaetognaths by R. von Ritter-Zahony 1917. — Part IV. AnneUds I, by Hjahnar Ditlevseti (6 plates and 24 figures in the text) 1904. Vol. V, Part I. Pennatulida by Hector F. E. Jungersen (3 plates). .. 1912. — Part II. Ctenophora bj' Th. Mortensen (10 plates and 15 figures in the text) . .' 1912. — . Part III. Ceriantharia by Oskar Carlgren (5 plates and 16 figures in the text) 1913. — Part IV. Zoantharia by Oskar Carlgren (7 plates and 6 figures in the text) 1914. — Part V. Stylasteridae by Hjahnar Broch (5 plates and 7 figures in the text) 1916. — Part VI. Hydroida, Part I, by Hjahnar Broch (2 plates and 20 figures in the text) 1918. — Part VII. Hydroida, Part II, by Hjahnar Broch (i plate and 95 figures in the text) 1919. — Part VIII. Medusae, Part I, by P. L. Kramp (5 plates, 17 figures in the text, and 14 maps) 1921. — Part IX. Actiniaria, Part I, by Oskar Carlgre?i (4 plates and 210 figures in the text) 1902. Vol. VI, Part I. Porifera, Part I, Homorrhaphidae and Heterorrhaphidse by Will. Lundbeck (19 plates) 1905. — Part II. Porifera, Part 2, Desmacidonidse (Pars) by Will. Lund- beck (20 plates) 1910. — Part III. Porifera, Part 3, Desmacidonidas (Pars) by Will. Lundbeck (11 plates) Kr. 25,00 8,00 13,00 Sh. 30) II) 18) 4.75 ( - 7) 9.75 ( - 13) 8,00 6,00 ( - II) ( - 9) 8,00 . - II) 13,00 (- 18) 15,00 ( - 18) 20,00 ( - 24) 9.50 20,00 19,00 0,50 ( - 13) ( - 24) ( - 23) (- I) 6,50 6,50 - 9) - 9) 10,50 - 14) 6,00 - 9) 7,00 - 10) 4.75 - 7) 4.75 ( - 7) 12,00 1 - 16) 12,50 ( - 17) 20,00 ( - 24) 17,00 ( - 22) 20,50 ( - 25) 12 00 ( 16)