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BRITISH ZOOPHYTES.

" Antequam progrediar, non ab re fortasse fuerit objectioni alicui quas in me moved potest occurrere. Non deerit scilicet qui me vaiise curiositatis argiiat, quod res adeo viles et abjectas, ludlius in vita usus, indagaverim, iisque descri-

bendis tantum temporis et operae impenderim Cui respondeo, Quod Dei

opera sunt in quibus contemplandis memet exerceo : quod Divinae Artis et Po- tentiffi effecta, quibus exquirendis subsecivas horas addico : quod Ili.e me in hunc mundum introduxerit, tam inexplicabili rerum varietate instructum et or- natum ; quodoculis, quosmihi contiilit, ea videnda, animo consideranda objecerit. In Dei ergo contumeliam redundat, quod haec, quae eum creasse negare non

audes, supeiTacanea et inutilia esse affirmes Dices, Majora et magis neces-

saria studia sunt, quae totum hominem requirunt. Respondeo, Majoribus istis me majorem euram impendere, interim tamen minora haec et lenora non opus est ut prorsus negligam ; Utrique penso sufficio ; utrique temporis abunde sup- petit, modo id prudenter dispensem, modo eaveam ne qua ejus pars omnino va- cua prseterlabatur. Vitam (ut recte Seneca) non accepimus brevem sedfecimus, nee inopes ejus, sed prodiyi sxtmus. Deinde Medici etiam severiores aliquam tem- poris portionem recreationibus deputant. Hisce ego studiis et inquisitionibus memet recreo et oblecto. Quod alii venationibus, aucupiis, confabulationibus, lusibus insumunt, illud ego " Zoophytis" indagandis, colendis, contemplandis im- pendo. Recreat et refocillat animum, quamvis laborios.ani sit, ilium quocmique oblectatur." Raius.

llUNTEn BY JOHN STABK, EDlNBUKC.Ii.

HISTORY

OF THE

BRITISH ZOOPHYTES

BY

GEORGE JOHNSTON, M. D. Edin.

I'KI.l.OW OF THE ROYAL COLLEGE OF SURGEONS, AND EXTRAORDINARY MEMBER OF THE ROYAL MEDICAL SOCIETY OF EDINBURGH.

AKMS OF THE TOWN OF BERVVrCK-UPO.V-TWEED.

W. H. LIZARS, EDINBURGH :

S. HIGHLEY, 32, FLEET STREET, LONDON; AND

W. CURRY, JUN. & CO., DUBLIN.

MDCCCXXXVIII.

\S38

O'/

i^y

^/f^^//^yy.////rM/'////y , ■

paribmis studiis et amore devinctisr

^^ / // Q^^^ yy^' '*'^y

PREFACE.

A Hum nee spiro, ncc si)ei"().

Since the publication of Ellis's Essay on Corallines in the year 1755, no separate work has appeared in illustration of our native Zoophytes. In the meantime, and more especially within these few last years, a much more accurate knowledge of their structure has been attained, and many species have been added to the list ; and it has been my object to give here an account of these discoveries, to connect them with what had been previous- ly made known, and to combine the whole under a system more in harmony with the anatomy of the objects than has hitherto been done. If I have succeeded in bringing within a convenient volume, the materials that at present lie scattered through many expensive and miscellaneous ones, some of them too of difficult acquisition, I may, perhaps, claim the merit of having conferred no inconsiderable benefit on the student, even should his future studies convince him that I have not forwarded or enriched this particular branch of natural history by any no- velties. Originality indeed has been less my aim than fulness and accuracy of compilation ; but I have endeavoured to quali- fy myself for this apparently humble task by many personal re- searches and observations on the species that are found in my own neighbourhood, under the conviction that a compiler will rarely succeed in giving a correct idea or representation of the objects

vi PREFACE.

under investigation without a direct acquaintance with them. It is indeed desirable that the author of" a work of this kind shoidd have examined all the species, and in various distant lo- calities, that he may justly characterize them, and estimate the extent of their variations ; nor was the circumstance of the com- parative unmoveableness to which a medical practitioner is doomed unconsidered as a bar to my own competency, but the love of the subject prevailed, especially when friends were readi- ly found to contribute to the removal of the difficulty. To them I have in this place to render my grateful acknowledge- ments. To Mr Bean of Scarborough, Dr Coldstream of Leith, J. V. Thompson, Esq. Inspector of Hospitals, for some time resident in Cork, and the Rev. David Landsborough of Ste- venston in Ayrshire, I stand indebted for numerous specimens ; and similar communications of less extent have been sent me in a friendly manner by John Edward Gray, Esq. of the British Museum ; Mr Robert Embleton, surgeon in Embleton ; Messrs Alder and Bowman of Newcastle ; Mr Teale of Leeds : J. Hosfo- Esq. of Norton ; and Messrs Macgillivray and P. W. Mac- lagan of Edinburgh. One other name must not be forgotten, for, besides a friendly interest in the book, and his revision of it during its progress through the press, I have had the kind as- sistance of the Rev. Thomas Riddell, of Trinity College, Cam- bridge, whenever the assistance of a classical scholar was re- quired.

I am not certain that any apology will be deemed necessary for the notes and quotations which have been introduced with considerable liberality, for the tastes of the naturalist have ever seemed to me akin to those of the antiquary ; and this has always been a favourite mode of illustration with the latter. It is one that chimes in with my own humour, and the indulgence of it seemed at least harmless on the present occasion. Many of these notes are devoted to notices of the individuals who, so far as I could learn, were the first to notice the species of

PREFACE. vii

zoophyte to which their names are respectively affixed, — foUow- \ng immediately the specific character. This has been a pleasing- inquiry. Smit with the beauty — real or fancied — of the objects of his study, a curiosity is naturally awakened to discover the name and degree of the person who had first deem- ed it worthy of his examination and participated in our pleasure, for we conclude assuredly that he who had taken the trouble to record the name and treasure up the object, was one of like mind, and imbued with much of the same affections and dispositions as ourselves. Some of them were found to be men of renown,— others in whom I felt a deeper sympathy, are now forgotten, their name and their labours swallowed up in the higher and more enduring reputation of those whom they were honoured to assist and delighted to serve. The genuine naturalist will not censure this " fond attempt" to restore the faint traces of men who had sought the best occupation of a leisure hour in congenial pursuits and studies ; but rather will with me lament the obscurity and shortness of their " simple annals."

" Paullum sepultse distat inertiae " Celata virtus. Non ego te meis " Chartis inornatum silebo, " Totve tuos patiar labores

" Impune carpere lividas

" Obliviones. * Hor. Carm. iv. 9.

It v/as gratifying to remark that most of my predecessors in this field of inquiry were members of the medical profession. How largely natural science, in all its branches, has been in- debted for its progress to this body is too notorious to be insisted

* The first stanza in Shenstone's " School -mistress" may serve as a translation of this passage -.

' ' Ah me ! full sorely is my heart forlorn,

To think how modest worth neglected lies ;

* * « * * *

let me try To sound the praise of merit, ere it dies, Such as I oft have chanced to espy, Lost in the dreary shades of dull obscurity."

viii PREFACE.

on ; but it has been less noticed that the men who thus occu- pied themselves in acquiring and forwarding a knowledge which many may deem purely ornamental, were the same individuals who were most engaged in the active discharge of the duties of their profession, and the most instrumental, to its advance. Boer- haave, Cullen, Hunter, Darwin and Jennerare very memorable instances of this fact, which is illustrated with lesser brilliancy in Lister, Sloane, Mead, Fothergill, Lettsom, Sims, Maton, in Withering of Birmingham, in Percival and Hull of Manches- ter, in Pulteney of Dorset, Stokes of Chesterfield, and nume- rous others whose names will occur to every one conversant with the history of medicine. This is only what on reflection might have been anticipated, for that very activity of mind and per- spicacity which originated and upheld their sagacity and suc- cess as practitioners, was sure to carry them far in whatever side-path the natural bent of their taste led them for the oc- cupation and entertainment of the leisure hours which the busi- est must have or may create. Idleness has no leisure. Were it necessary I might safely shelter myself under the cover of these exemplars, in the contemplation of whose lives I have of- ten nurtured my love to my profession, — and hence, perhaps, an ambition to follow them even at a far distance ; — but there never was a time when it was necessary to vindicate to any but the ignorant the erratic excursions of medical men into the fields of science and literature, for assuredly the rank which the pro- fession as a body has taken and holds in public estimation de- pends for its patent, in part at least, on the scientific and lite- ary character of its professors ; and by continuing to support that character they will best secure it from the vulgarity of a connnon mercature, or the selfishness of a venal quackery.

Zoophytes present to the physiologist the simplest indepen- dent structures compatible with the existence of animal life, cnabliufr him to examine some of its phenomena in isolation and free frtnn the obscurity which greater complexity of aiiato-

PREFACE. ix

my entails : the means of their propagation and increase are the first of a series of facts on which a theory of generation must rise ; the existence of vibratile cilia on the surfaces of membranes, which has since been shewn to be so general and influential among animals, was first discovered in their study ; and in them is first detected the traces of a circulation carried on indepen- dently of a heart and vessels. The close adhesion of life to a low organization, — its marvellous capacity of redintegration ; the organic junction of hundreds and thousands of individuals in one body, the possibility of which fiction had scarcely ventured to paint in its vagaries, have all in this class their most remark- able illustrations. On the geologist zoophytology has pe- culiar claims. Its subjects are apparently the first of animals which were called into existence, and from that high date to this time, they have played a part in the earth's mutations, from chaos to the present well ordered scene, greater perhaps than any other class of beings. Separating from the waters of the ocean the calcareous matter held in solution, they reduce it to a solid state ; constructing therewith their varied j)olypidoms or corals which, by their continual growth, their coalescences, their enormous numbers and extent, first roughen the smooth basin of the sea, raise up reefs and ridges that obstruct the hitherto open course of navigation, and become ultimately the founda- tion of islets and islands that remain the " monumental relics" of the puny race. As now the process and change goes on in tropical seas, — so operated it, in the preadamic times, over the waters of the globe, for it is principally from the debris of poly- pous excretions that the extensive beds and quarries of chalk and limestone which are found in every region of the globe take

their original.* But it is to the zoologist that I exclusively

address myself in this work, and however considerations like the above may enhance the importance of the subject in the es- timation of others, they sway him little, and lie apart from his

* See Lamarck's Anim. s. Vert. ii. 10- b

X PREFACE.

more immediate objects. He finds his pleasure in the con- templation of their novel forms, in the examination of those cha- racters which distinguish them as species, in the quest of their mutual affinities, their relations and analogies with other beings, the order in which Creative Wisdom may seem to have called them into existence, their habits, economy and uses ; — and in all these things he is ever watchful to find a " moral compli- ment" that the pursuit to which his taste and constitution of mind has led him may be neither uninfluential nor virtueless on his heart.

The plates and wood-cuts which illustrate the volume are, with few exceptions, original, — engraved from drawings made for it by Mrs Johnston, who is herself the engraver of fourteen of them. The naturalist who may have attempted similar il- lustrations will appreciate the labour, perseverance and skill which has been bestowed upon them, and will not harshly censure any errors of detail which a minute criticism may dis- cover. As I could not have undertaken this history without her assistance, I may crave, from any one who shall find a merit in it, the ascription of that merit to my colleague.

Behwick-upon- Tweed, August 15, 18.38.

CONTENTS.

History of Zoophytology,	Page 3—29
Opinions of the Ancients,	3—4
Imperato,	4
Peyssonel and Reaumur,	5—7
Jussieu,	8
Peyssonel and Parsons,	10—11
Baker,	11—13
Ellis,	13—17
Linnaeus,	17—20
Baster,	20—23
Pallas and Ellis,	24—27
Nature of Sponges,	28—29 and 325
Zoophytes, definition of	30—31
Polypes, what? - -	32
Their distinction into two classes,	33
The structure of Ascidian polypes.	33—36
Hydraform polypes.	36 38
Asteroid polypes,	38 41
Helianthoid polypes.	41
Circulation of the Sertulariadae,	41—43
Ascidian polypes.	43—45
Food of Polypes,	45—46
Generation of polypes, and their ova,	46—48
Evolution of the ova,	48—49
The ova of the Flustrae,	50—51
Polypidoms, Chemical composition of.	52—33 and 76 77
Their forms,	53—54
Their formation,	55
Zoophytes, classification of, by Ellis,	55
Linnaeus,	56
Pallas,	57
MuUer,	58
Blumenbach,	39
Cuvier,	59—6 1
Lamouroux,	62—64
Lamarck,	65—66

xii CONTENTS.

Zoophytes, classification of, by Fleming, - - Page 68 — 71

Latreille, - - - - 71

Rapp, - _ - 72

Blainville, - 73—75

Zoophytes, their division into four orders, - 75 76

Zoophyta Hydroida, definition of, - - 81

general observations on - 81 — 91

their Families and Genera, - 91 — 92

Family Hydraidae, - 93—108

Tubulariadae, - 109—118

Sertulariadae, - 119—159

Asteroida, definition of, - - 1^3

general observations on - 163 — 174

their Families and Genera, - I '*

Family Pennatulidae, - 175 — 181

Gorgoniadae, - 182 — 186

Alcyonida?, - 187—192

Helianthoida, definition of, - - 195

general observations on - 195 — 204

their Families and Genera, - 205

Family Madrephylliasa, - 206—209

Actiniidae, - 210—234

Ascidioida, definition of, - " 237

general observations on - 237 — 246

their Families and Genera, - 247 — 248

Family Vesiculariadse, - 249—259

Crisiadae, - 260—266

Tubuliporidae, - 267—272

Celleporidae, - 273—282

Escharidce, - - 283—299

Alcyonidulae, - - 300—307

Limniades, - - 308 — 324

Note on the sexes of Zoophytes, - - 325

the anatomy of the Hydra, - - 326

the cells of the Escharidoe, - - 327

BRITISH ZOOPHYTES.

PART I.

The History of Zoophytology ; and on the Structure, Physiology, and Classification of Zoophytes.

TUBULARIA RAMEA.

" In nova fert animus mutatas dicere formas " Corpora." — Ovid. Metamorph. i.

" Ipse maniis haustu victrices ahluit unda -. Anguiferumque caput dura ne laedat arena, Mollit humiim foliis, natasqiie sub tequore virgas Steniit, et imponit Phorcynidos ora Medusse. Virga recens, bibulaque etiamnum viva medulla Vim rapuit monstri, tactuque induruit hujus, Percepitque novum rarais et fronde rigorem. At pelagi nj'mpha; factum mirabile tentant Pluribus in virgis, et idem contingerc gaudent : Seminaque ex illis iterant jactata per undas. Nunc quoque curaliis eadem natura remansit, Duritiem tacto capiant ut ab aere, quodque Vimen in Eequore erat, fiat super sequora saxum."

Ovid. Metam. iv.

BRITISH ZOOPHYTES.

CHAPTER I. History of Zoophytology.

The natural productions about to occupy our attention, have been denominated Zoophytes because, according to some phy- siologists, they partake of the nature both of vegetables and animals, and connect the two kingdoms of organized matter ; or because, as others define the term, having the outward sem- blance of sea-plants, they are yet in reality the formations of little animals or polypes that nestle in the cells or tubes of the zoo- phyte, to which they are organically and indissolubly connected.

Little more than a century has elapsed since the first dis- coveries were made, on which these opinions are founded. Pre- viously to that time zoophytes were considered the undoubted subjects of the vegetable kingdom, naturalists being obviously led to this allocation of them by their arborescent appearances, in which it were vain to trace any likeness to any common ani- mal forms,— and by their permanent fixedness to the objects from which they grow, for zoophytes are attached by means of a disk or tubular fibres much in the same way that marine plants are, while the capabiHty of moving at will from place to place was deemed to be the principal character of distinction between the two classes of animated beings. The zoologist claimed none of them, if we except the Actinise or animal-flowers, for his province and study, but left them without dispute to botani- cal writers ; and if any of these, in reference to a very few zoo- phytes of the least arborescent character, hazarded a whispered conjecture that they were wrongly classed, it died away in the ut-

4 HISTORY OF ZOOPIIYTOLOGY.

terance, and raised no echo to awaken further inquiry. The only opposition to the botanical theory came from the mineralogists, who some of them questioned the vegetability of such of these productions as were of a hard and stony nature, contending they were rather rocks or stones formed by the sediment and agglutination of a submarine general compost of calcareous and argillaceous materials, moulded into the figures of trees and mosses by ,the motion of the waves, by crystallization, by the incrustation of real fuci, or by some imagined vegetative power in brute matter. But although not more — perhaps less repug- nant to the outward sense than the opposite hypothesis, yet the mineral theory seems at no time to have obtained very ge- neral favour or credit ; and accordingly we find that, in the works of Tournefort and Ray,* the leading naturalists of the age imme- diately antecedent to the discoveries which led to the modern doctrines, the zoophytes, whether calcareous and hard, or horny and flexible, were arranged and described among sea-weeds and mosses without any misgivings concerning the propriety of doing so.

Ferrante Imperato, an apothecary in Naples, was the first naturalist, according to M. De Blainville, distinctly to publish, as the result of his proper observations, the animality of corals and madrepores,-|- and he is said to have accompanied the de-

* III his " Wisdom of God in the Creation," Ray has, however, reckoned the Lithnphijta among " inanimate mixed bodies." Of these, he says, " some have a kind of vegetation and resemblance of plants, as corals, pori, and fungites, Avhich grow upon the rocks like shrubs." — p. 83, duod. Lond. 182G. His opi- nions on this point were probably unsettled ; and certainly many naturalists be- lieved that Ovid only exj)ressed the simple fact when he wrote — " Sic et curalium, quo primum contigit auras " Tempore durescit ; mollis fuit herba sub undis."

Metam. lib. xv.

f Man. d'Actinol. p. \A Lamouroux on the contrary places Imperato on the

same level with Gesner, Boccone, and Shaw — none of whom had any distinct notion of the animality of any zoophytes, and had no doubt of the vegetable nature of almost all of them. " Les observations de ces hommes celebres, au lieu d'eclairer les naturalistes sur cette branche interessante de la science, em- brouillaient encore plus son etude." — Lam. Cor. Flex. Introd. p. xiv. My copy of Imperato's work is of the edition printed at Venice in 167'2, folio. It is written entirely in Italian, and, being ignorant of that language, I can give no opinion of the value of its letter-press. The only copper-jjlate is a very curious one representing the interior of Imperato's museum, which appears to have been a very elegant and copious collection of curiosities, a servant pointing with a

HISTORY OF ZOOPHYTOLOGY. 5

scriptions of the species which fell under his notice with illus- trative figures of considerable accuracy. His " Historia Natu- vale," of which De Blahiville assuredly speaks in very exag- ireratinof terms when he represents it as one of the most im- portant works in the history of zoophytology, was prmted at Naples in 1599 ; but although reprinted some years after- wards (1672), the book, and the knowledge it contained, had sunk into such complete oblivion, that when Peysso^nel, in the year 17*27, communicated the same discovery to the Academy of Sciences in Paris, it was received by the members of that learned body in a manner which is sufficient to convince us that it was entirely new to them, and exposed the author to the ob- loquy and censure which are the usual portions of an original discoverer.

Some time previously to the publication of Peyssonnel's dis- covery, those who maintained that the stony zoophytes were plants had received a strong corroboration of their opinion from the researches of Count Marsigli, who, having detected the ex- istence of polypes in coral and madrepore, had, under the influ- ence of the fashionable theory, described them as being literal- ly their blossoms or flowers.* Peyssonnel, therefore, had to contend not only against the prejudices of the vulgar based on appearances which spoke direct to the outward sense, but against the actual observations of a naturalist of acknowledged merit ; and the observations of Peyssonnel, although numerous and unequivocal, were yet mixed up with so much that was fanciful or erroneous, that it is not wonderful his opinion was received with coldness and suspicion. Reaumur, to whom Peyssonnel's communication was intrusted, even concealed the name of the

rod and directing the attention of two wondering visitors to the more remarkable of them, while a third leans against a cabinet, and surveys,

" not without much content

" Its many singularities." The book contains besides many wood-cuts of a miscellaneous kind, very tolera- bly engraved for the age. The Zoophytes figured belong chiefly to the Litlio- phyta, with some Sponges and Alcyonia. The opinions of Rumphius seem to have been as explicitly stated as those of Impcrato, but they effected nothing — Pall. Elench. 14, and 275.

* " Ce fut une decouverte qui fit grand bruit dans le monde naturaliste, que celle des fleurs du corail." Reaumur — Marsigli's work was published in 1711. His name is sometimes written MarsillL — For an account of his works see Hal- ler, Bib. Hot. i. G30.

0 HISTORY OF ZOOPHYTOLOGY.

aitllior when he laid it before the Academy, with the benevo- lent intention doubtless of shielding him from the scorn and ri- dicule that might possibly be the lot of one who had ventured to contradict the observations of an Italian Count, and to oppose the established belief;* and he mimediately afterwards read, before the same academicians, an essay of his own, in which he opposed the theory of Peyssonnel with numerous objections, and attempted to explain the growth of coral in accordance to the admitted principles of vegetable physiology.f

The memoir in which Peyssonnel originally proposed his doc- trine does not appear to have been published : the only account

1 have seen of it is contained in the essay of Reaumur just al- luded to. He maintained that what Marsiofli had described as the blossoms of coral, were true animals or insects analogous to the Actiniae or sea-anemonies ; that the coral was secreted in a fluid form by the inhabitant Actinise, and became afterwards fixed, hard, and changed into stone ; and that all other stony sea-plants, and even sponges, are the work of different insects, particular to each species of these marine bodies, which la- bour uniformly according to their nature, and as the Supreme Being has ordered and determined. Reaumur remarks, that these opinions were not entirely the offspring of fancy : it would have been more candid and just had he said they were simply the convictions of a practical naturalist, who had long and pa- tiently studied the productions in question, in their native sites on the coasts of France and of Barbary. Peyssonnel had seen the polypes of coral and of the madrepores ; he recognized their resemblance to the naked animal flowers; he had witnessed their motions, — the extension of their tentacula, and the con- traction and opening of the oral aperture ; he ascertained, that, unlike flowers, they were to be found the same at all seasons ;

* " L'cstime que j'ai pour M. Peyssonnel me fit meme eviter de la nommer pour I'auteur d'un sentiment qui ne pouvoit manquer de paroitre trop hasarde." — Reaumur.

f Observations sur la formation du corail, et des autres productions appellees

Plantes pierreuses. Par M. de Reaumur " II prend pour une Plants I'ecorce

grossiere et sensible du corail, tres-distincte de ce que nous appellons corail, et de plus une autre ecorce bcaucoup plus fine, et que les yeuxne distinguent point do la vraye substance coralline qu'elle revet ; et tout le reste du corail, presque toute la substance coralline n'est qu'imc pierre sans organisation." — Hist, de I'Acad. Roy. des Sc. 17"27. p. 51. and more particularly his own memoir in the same vol. p. 380.

HISTORY OF ZOOPHYTOLOGY. 7

that their corruption exhaled the odour ; their chemical ana- lysis discovered the constituent principles of animal matters ; and that' the stony part of them exhibited no trace of vegetable or- ganization : and opinions deduced from such data, abstracting his analogical reasoning of no value and little applicability, might have been sufficient to have attracted at least some attention had his opponent been less influential, or his own reputation and rank somewhat greater. *

The name and doctrine of Peyssonel lay in this manner un- known and neglected, until the remarkable experiments of Abraham Trembley, in 1741, on the reproductive powers of the fresh-water polypes, "f- and more especially his discovery of the Plumatella, itself a plant-like animal production, while they ex- torted the wonder and admiration of every one engaged in the study of natural science, were the means of recalling to the re- collection of Reaumur the views of Peyssonnel ; and he now became forward in promoting such inquiries as seemed likely to confirm and extend them. He himself appears to have repeat- ed the experiments of Trembley, and had an opportunity of ob- serving the habits of the Plumatella ; and, as he remarks, since the number of species of animals which are covered by the wa- ters of the sea is much greater than that of the fresh waters, so it seemed natural to presume that not only would polypes be found in the ocean, but in greater numbers and variety than in ponds, rivers or rivulets. To ascertain the validity of this con- jecture, and to settle if possible the discrepancy between the observations of Marsigli and Peyssonnel, his friends Bernard

* Peyssonnel is remembered solely by this discovery. " M. Peyssonnel, dis- posed from his youth to the study of natural history, after having qualified him- self for the practice of medicine, applied himself mth great diligence to that sci- ence, to which his inclination so strongly prompted him, and being a native of, and residing at Marseilles, he had the opportunity of examining the curiosities of the sea, which the fishermen, more especially those who search for coral, fur- nished him with." — Phil. Trans. He was subsequently appointed Physician- Bo- tanist to " His Most Christian Majesty" in the island of Guadalupe, and had an opportunity of prosecuting his researches on the coast of Barbary. He is the author of two or three communications in the Phil. Trans., of which the most interesting is " An account of a \'isitation of the Leprous persons, in the isle of Guadalupe" in the volume for the year 1757.

+ In the Phil. Trans, for 1742, the reader will find a full account of this dis- covery.

8 HISTORY OF ZOOPHYTOLOGY.

de Jussieu and Guettard * proceeded, in the autumns of 1741 and 1742, to different parts of the coasts of France with the view of examining their zoophytical productions ; and both were soon satisfied of the truth of the animal theory. Bernard de Jussieu in particular shewed that it was equally applicable to many zoophytes which Peyssonnel had not examined, and whose animalityhad not yet been suspected, viz. the flexible and delic'ate iSertulariai, the Flustra, and the Alcyonium or Lobularia, the latter of which seems to have excited much astonishment by the protrusion of its thousands of polypes of a size large enough to be seen and examined at ease with the naked eye. f

The memoir which Jussieu presented to the Academy of Sciences in Paris is short, but characterized by great distinct- ness and precision in the detail of his observations, and illus- trated with excellent figures ; — his aim being evidently not to entrap our blind assent by a declamatory display of the new wonders opened up in science, but to prove his conclusion to be the true one in the eye of reason and sobriety. He limits his descriptions and remarks to four species, viz. Alcyonium di- gitatum, Tubularia indivisa, Flustra foliacea, and Cellepora pumicosa, which seem to have been selected as examples of the more remarkable tribes, for it is evident that he had examined manymore, buthisobservationson them were reserved for another memoir which, I believe, was never written. X — Reaumur's ad-

Lamouroux speaks highly of the labours of this naturalist, whose attention

seems to have been chiefly directed to fossil polypidoms and to sponges Corall.

Flex. Introd. p. xvii. See also Hall. Bib. Bot. ii. 341.

f E.vimen de quelques productions marines qui ont ete mises au nombre des Plantes, et qui sont I'ouvrage d'une sorte d'Insectes de mer. Par. M. Bernard de Jussieu. J 4th Nov. 1742. Published in 1745 See Hall. Bib. Bot. ii. 281.

I That Jussieu had ascertained the animality of the Sertulariadte is, I think, indisputable from the following passage. " II s'en presentoit ensuite quantite de celles qu'on appelle Corallines, les unes pierreuses dans lesquelles je ne se- marquai rien, et les auti'es dont les tiges et les branches, et ce qiu passoit pour feuilles, etoient d'une apparence membraneuse, dans lesquelles je decouvris que ce qu'on y prenoit pour feuilles disposees alternativement, ou dans un sens op- pose, n'etoit autre chose que de petits tuyaux contenant chacun un petit insecte." — Mem. de I'Acad. Roy. des Be. an. 1742. p. 292 Reaumur is still more ex- plicit. : " Apres avoir observe dans I'eau meme de la mer plusieurs especes deces productions si Men conformees a la maniere des plantes, il vit sortir des bouts de toutes leurs bi'anches et de tous leurs noeuds, ou de toutes leurs articulations, dc petits animaux qui, commeles polypes a panache d'eau douce, se donnoient tantot pins, tantot moins de mouvemcnt, qui coinme ceux-ci s't'panouissoient en

HISTORY OF ZOOPHYTOLOGY. 9

vocacy of the new doctrine was in a more popular style, but not the less excellent. He gave a short exposition of the ascertained facts, — reviewed with the clearness of an eye-witness the dis- coveries of Trembley, — pointed out their relations to the ex- periments of Jussieu and Guettard, and how they mutually lent and borrowed strength, — palliated and explained away his for- mer opposition to Peyssonnel, — and declared his complete faith in the animality of Zoophytes, and his conviction that a nume- rous list of productions hitherto unexamined would be found to be of the same nature. " All that we have said," he thus con- cludes, " of the polypes of the sea, is merely a sort of adver- tisement which, however, cannot fail to produce the effect which we promise ourselves from it : it will direct undoubtedly the curiosity of naturalists who reside by the sea to insects so worthy of being better known. They will seek out the different species ; they will delight to describe to us the varieties presented in their forms never but remarkable ; they will study the figure and disposition of the cells of the various species, their manner of growth and reproduction and wherewithal they are nourished ; they will in short, place in a clear light every thing that has reference to the different polypidoms and their formation, so that a department of natural history, so interesting, so new, and as yet only sketched in outline, may be rendered as perfect as it merits to be." *

The appeal, eloquent as it was and from one having great influence, was however made in vain ; for whether from the in- veteracy of habit and our fondness of opinions long cherished, or from the fewness of the published observations whence the general conclusion was drawn, it seems certain that the new doc-

ccrtains temps, et qiii dans d'autres rentroient en entier dans leur petite cellide, hors de laquelle leur partie posterieure ne se tiouvoit jamais. Enfin, il (B. de Jussieu) reconnut que plusieurs espeees de ces corps, dont chacun avoit I'ex- terieur d'une tres-belle plante, n'etoient que des assemblages d'un nombre pro- digieiLx de cellules de polypes ; en un mot, que plusieurs de ces productions de la mer, que tous les botanistes que les ont decrites ont prises"pour des plantes et ont fait representer comme telles avec complaisance, n'etoient que des poly- piers.'" — Preface, Vol. vi. p. 71, 72. See also Amoenitates Aradeinicse, Vol. i. p. 185, for an enumeration of the species of Sertularia, &c., which Jussieu had examined, and considered to be animal productions. His account, however, of the animal of the Sertularia? is altogether erroneous.

" Memoires pour servir a I'histoire des Insectes, Tome sixieme, Paris, 1742. Quarto. Preface, from p. 68 to p. 80.

10 HISTORY OF ZOOPHYTOLOGY.

trines were everywhere received with doubts and suspicion, and beyond the immediate sphere of the Parisian academy, excited apparently so Httle interest, that no one was induced to enter into a practical examination of them. Donati indeed shortly after gave a minute and accurate description of the coral and its polypes, and a somewhat less detailed one of the madrepores, but his phraseology being botanical and his opinions unformed,* his researches were of little immediate service to the cause of the zoologists, and perhaps rather tended to support the errone- ous hypothesis which they were combating.f

Peyssonnel was still living, and it was impossible that this dis- cussion should not interest him. Accordingly we find that in 1751, he transmitted to the Royal Society of London a manuscript treatise on coral and other marine productions, J of which Dr Watson has given a review in the 47th volume of its Transac- tions, pubhshed in 1753. The treatise was sent to the English society, because " that in France some lovers of natural history do attribute and even appropriate to themselves his labours and his discoveries, of which they have had the communication ;" — a charge probably directed against Reaumur, but which the con- duct of that illustrious man, so far as appears, did not warrant. The treatise contains upwards of 400 quarto pages, and is the

Shortly after this, however, he made other observations which convinced him of the animality of coral. He says—" I am now of opinion, that coral is nothing else than a real animal, which has a very great number of heads. I consider the polypes of coral as the heads of the animal. This animal has a bone rami- fied in the shape of a shrub. This bone is covered with a kind of flesh, which is the flesh of the animal. My observations have discovered to me several ana- logies between the animals of kinds approaching to this. There are, for in- stance, Keratophyta, which do not diff-er from coral, except in the bone, or part that forms the prop of the animal. In the coral it is testaceous, and in the Keratophyta it is horny. "—Phil. Trans. (1757) abridg. xi. p. 83.

t New Discoveries relating to the History of Coral, by Dr Vitaliano Donati. Translated from the French, by Tho. Stack, M. D. F. R. S. (Feb. 7, 1750.)— Phil. Trans. Vol. xlvii. p. 95. Haller characterizes the original as " nobile opus, ex proprio labcre natum."— Bib. Bot. ii. 400.

f Traite du corail, contcnant les nouvellcs decouvertes, qu'on a fait sur le corail, les pores, madrepores, scharras, litophitons, eponges, et autres corps et productions, que la mer fom-nit, pour servir a I'histoire naturelle de la mer. By the Sieur de Peyssonnel, M. D. Correspondent of the Royal Academy of Sciences of Paris, of that of Montpelier, and of that of Belles Lettres at Mar- seilles. This treatise was never published.

HISTORY OF ZOOPHYTOLOGY. 11

result of the observations of above thirty years, but we find in it no facts in support of his theory additional to those already men- tioned, for the greater portion of it is occupied with many de- tails on the medical uses and other applications of coral which have no relation to the question at issue. It seems at first to have excited considerable attention amongf the members of the Royal Society, but Peyssonnel's endeavours were doomed ever to be unfortunate, for whatever favour his theory was likely to receive here was nipt in the bud by the opposition of Dr Par- sons, a naturalist of considei'able eminence, and an active mem- ber of the society. The analysis of Peyssonnel's treatise was read in May 1752, and in June of the same year, Dr Parsons read his answer,* which savours much of the supercilious dog- matism of a sceptical philosophy. He does not pretend that he had tested the doctrine of Peyssonnel by any experiments or observations, nor does he question his veracity, but he chose to consider the animals observed by Peyssonnel in the coral and madrepores as merely accidental settlers which had nothing to do with their growth, — occupants of mansions prepared for them by more active entities, — there being no " seeming power, propor- tion, and stability" in the polypes to render them capable of per- forming such works as they were thought to have done. " And indeed it would seem to me," says the learned doctor, " much more difficult to conceive, that so fine an arrangement of parts, such masses as these bodies consist of, and such reo'ular ramifi- cations in some, and such well-contrived organs to serve for ve- getation in others, should be the operations of little, poor, help- less, jelly-like animals, rather than the work of more sure vege- tation, which carries on the growth of the tallest and largest trees with the same natural ease and influence, as the minutest plant."

The mineral theory also found at this period its latest advo- cate. Henry Baker, during his numerous microscopical enqui- ries, had become familiar with the beautiful and regular " ve- getations" which many salts and earths assume in their crystal-

* A Letter from James Parsons, M. D. F. R. S. to the Rev. Mr Birch, Seer. R. S. concerning the Formation of Corals, Corallines, &c. For an account of Dr Parson's writings see Hall. Bib. Bot. ii. 340 ; and there is a short biogra- phical notice of him in Phil. Trans, abridg. viii. 692.

12 HISTORY OF ZOOPHYTOLOGY.

lizations from a fluid state, and, seeing nothing more uniform or beautiful in the stony corals and corallines, he was naturally led to give an easy assent to that doctrine which taught that these were all the result of similar depositions. The new opinions might be true or not when restricted to the pliant horny coral- lines, (though he inclined to believe in their vegetable origin,) but it was unnecessary to call in the agency of animalcules to explain the formation of the hard stony kinds, which indeed seemed beyond the power of an almost gelatinous animalcule to excrete and laborate. Nor would he believe these to be sea- plants, but rather of a mineral nature and origin. " The rocks in the sea on which these corals are produced," he says, " are undoubtedly replete with mineral salts, some whereof near their surface, being dissolved by the sea-water, must consequently sa- turate with their saline particles the water round them to a small distance, where blending with the stony matter with which sea- water always abounds, little masses will be constituted here and there and affixed to the rocks. Such adhering masses may be termed roots .- which roots attracting the saline and stony par- ticles, according to certain laws in nature, may produce branch- ed or other figures, and increase gradually by an apposition of particles ; becoming thicker near the bottom where the saline matter is more abounding, but tapering or diminishing toward the extremities, where the mineral salts must be fewer, in pro- portion to their distance from the rock whence they originally proceed. And the different proportions of mineral saline par- ticles, of the stony or other matter wherewith they are blended, and of marine salt, which must have a considerable share in such formations, may occasion all the variety we see. Nor does it seem more difficult to imagine that the radiated, starry, or cellular figures along the sides of these corals, or at the extre- mities of their branches, may derive their production from salts incorporated with stony matter, than that the curious delinea- tions and appearances of minute shrubs and mosses on slates, stones, &c. are owing to the shootings of salts intermixt with mineral particles : and yet these are generally allowed to be the work of mineral steams or exhalations; by which must, I think, be meant the finest particles of some metal or mineral incorpo- rated with and brought into action by a volatile penetrating

HISTORY OF ZOOPIIYTOLOGY. 13

acid, which carrvino; them alono- witli it into the fissures at least, if not into the sohd substance of such stones or slates, there de- termines them to shoot into these elegant branchings ; after the same manner, and frequently in the same figures, as the par- ticles of merq^u'y, copper, &c. are disposed and brought together by the salts in aqua fortis."*

But the progress of truth, although it may be delayed by op- position, cannot be permanently arrested. The converts to the new doctrines were indeed few, but much had been done to fa- cilitate their future reception, for the slumber of prejudice had been broken, the hold of the ancient opinions on the affections had been loosened, and men no longer startled into scepticism when they heard of animals that in their productions mimicked the most beautiful and delicate vegetable forms, f The mind of naturalists was thus in some measure prepared for the change on the very eve of being effected by the labours and assiduity of a member of that very society which had lately listened, with apparent approbation, to the reveries of Dr Parsons.

John Ellis — the name of the individual alluded to — was a merchant in London, who devoted his leisure to the study of natural history, in which he attained so considerable knowledge as to gain easy access to the Royal Society, and the acquain- tance and correspondence of the most celebrated naturalists of his time. He seems to have attached himself more particular- ly to the economical department of botany, and seized every opportunity to introduce foreign plants to our gardens, especial- ly such as were remarkable from furnishing any material em- ployed in the arts and manufactures ; and he was equally solici- tous to acquire and diffuse accurate information relative to any natural productions which might be rendered subservient to the necessities or comforts of mankind. He was fond also of amusing himself in making imitations of landscapes by the cu- rious and skilful disposition of delicate sea-weed and corallines

* Employment for the Microscope, p. 218-20. Lond. 1753.

f " For it is not because an'opinion is true, that others mil therefore adopt it. It must at the same time be congruous with our other impressions, and admit of being dovetailed into them, or it wUl be rejected, for it is judged of by its conformity to the previous acquisitions, and is disliked and coudemned if incom- patible with them." — Turner, Sac. Hist, of the World, Vol. ii. p. 19.

14 HISTORY OF ZOOPHYTOLOGY.

on paper : and it was this amusement that directed his enquiries into the nature of the latter, for, attracted by their beauty and neatness, he was induced to examine them minutely with the microscope, by the aid of which he immediately perceived " that they differed not less from each other, in respect to their form, than they did in regard to their texture ; and that, in many of them, this texture was such, as seemed to indicate their being more of an animal, than vegetable nature." These " suspi- cions," as he modestly terms them, were communicated to the Royal Society in June 1752; and, encouraged by some of the members, he prosecuted this enquiry with such ardour, and care, and sagacity, that in August of the same year, he had fully convinced himself " that these apparent plants were ramified animals, in their proper skins or cases, not locomotive, but fixed to shells of oysters, mussels, &c. and to Fucus's."*

Ellis, however, was not forward to pubhsh his discovery : he waited further opportunities to confirm the accuracy of his first observations, and to institute other experiments to remove what- ever appeared hostile to the doctrine, which at length he fully explained to the members of the Royal Society in a paper read before them in June 1754: and it was made more generally known in the following year by the publication of his " Essay towards a natural history of the Corallines, and other marine productions of the like kind, commonly found on the coasts of Great Britain and Ireland ;"— a work so complete and accurate that it remains an unscarred monument of his well-earned re- See the Introduction to his Essay on the Corallines of Great Britain. It is from this work, and from the valuable " Selection of the Correspondence of Liimffius, and other naturalists, from the original manuscripts, by Sir James Ed- ward Smith/' 2 vols, 8vo. Lond. 1821, that I derive my account of Ellis's opi-

nions. Sir J. E. Smith commences his memoir by saying " John Ellis, F. R. S.,

iUustrious for his discover?/ and complete demonstration of the animal na- ture of Corals and Corallines, was a native of Ireland." We have seen that he has no claim to this discovery, though he himself seems to have thought so, and never makes mention of his predecessors in the same field. A Professor Butt- ner at Gottingen, who had been in England, and become acquainted with Ellis, who calls him an " excellent botanist," unhesitatingly claimed Ellis's discoveries for his own, but a more bare-faced literary theft has not been recorded, and its detection has rendered the name of the German Professor infamous— Lin. Cor- resp. Vol. i. p. 170 and 179,— For a list of Ellis's writings the reader may con- sult Hall. Bib. Bot ii. 433, and the Introd. to Soland. Zooph. p. viii.

HISTORY OF ZOOPIIYTOLOGY. 15

putation as a philosophical inquirer, and is even to this day the principal source of our knowledge in this department of natural history. In several essays presented subsequently to the Royal Society, and published in their Transactions, he continued to illustrate and extend his opinions, and defended them so suc- cessfully against his opponents, that they soon came to be very generally adopted.

There was nothing unformed nor mystical in Ellis's opinion. Certain marine productions which, under the names of Litho- phyta and Keratophyta, had been arranged among vegetables, and were still very generally believed to be so, he maintained and proved with a most satisfactory fulness of evidence, to be entirely of an animal nature — the tenements and products of animals similar in many respects to the naked fresh-water polype. By examining them, in a living state, through an ordinary mi- croscope, he saw these polypes in the denticles or cells of the zoophyte ; he witnessed them display their tentacula for the cap- ture of their prey, — their varied actions and sensibility to ex- ternal impressions,^ — and their mode of propagation ; he saw further that the little creatures were organically connected with the cells and could not remove from them, and that although each cell was appropriated to a single individual, yet was this united " by a tender thready line to the fleshy part that occu- pies the middle of the whole coralline,"" and in this manner con- nected with all the individuals of that coralline. The conclu- sion was irresistible — the presumed plant was the skin or cover- ing of a sort of miniature hydra, — a conclusion which Ellis strengthened by an examination of the covering separately, which, he said, was as much an animal structure as the nails or horns of beasts, or the shell of the tortoise, for it differs from " sea-plants in texture, as well as hardness, and likewise in their chemical productions. For sea-plants, properly so called, such as the Algae, Fuci, &c. afford in distillation little or no traces of a volatile salt : whereas all the corallines afford a considerable quantity ; and in burning yield a smell somewhat resembling that of burnt horn, and other animal substances ; which of itself is a proof that this class of bodies, though it has the vegetable form, yet is not entirely of a vegetable nature." *

• Dr Good is in error when he states that the ammoniacal smell from burnt

16 HISTORY OF ZOOPHYTOLOGY.

Ellis 'taught no novel doctrine, but he gave it fixidity and currency ; and he moreover applied it to those very zoophytes which possessed the vegetable appearance in the most perfec- tion, many of which he was the first to notice, and which he il- lustrated with a series of figures of unequalled accuracy. * He rarely went beyond the mere statement of the facts witnessed, or what seemed an unavoidable inference from them ; but, per- haps, he deserted his usual caution when, from analogy princi- pally, he asserted that the articulated calcareous corallines (Co- rallina, Lin.) and sponges, of a very different structure from coral, madrepore, or the horny corallines, were also like them, manifestly the places of abode of diflferent species of polypes. In the former ( Corallina) he had indeed detected some slender fibres which, it was presumed, might be parts of polypes, but this observation he was never able to confirm, and it was rather because of the porous structure of the corallines, than from any thing else, that he inferred the existence of polypes in them, — a structure which he had examined with minute accuracy, and shown to be essentially different from any known vegetable tis- sue,— and, secondly, because of their chemical constituents, of which he procured an accurate analysis to be made. — With re- gard to the Sponges, Ellis, as Peyssonnel had previously done, supposed at first that the regular holes observable in dry speci- mens, strongly indicated their being once filled with animals; but when after repeated examinations of recent sponge, he could detect none, this conjecture was abandoned, and so thoroughly

zoophytes was the principal fact for placing them in the animal kingdom. — Book of Nature, i. 175 and 210.

* As mentioned above, Bernard de Jussieu knew that the Sertulariadse — the zoophytes here alluded to — were animal productions, but no detailed account of his observations seems ever to have been published. Trembley had made the same discovery. Dr Watson, in his account of Peyssonnel's treatise in 1752, tells us that Mr Trembley shewed him, " at the late excellent Duke of Rich- mond's" the small white polypes of the Corallina minus ramosa alterna vice den- ticulata of Ray, " exactly in form resembling the fresh-water polype, but infinite- ly less." " When the water was still, these animals came forth, and moved their claws in search of their prey in various directions ; but, upon the least motion of the glass, they instantly disappeared." P. 463 — Linnseus, however, in refer- ence to the observations made previous to Ellis, says they are " inchoate, non ad pleimm confectae, et desiderentur adhuc quam plurima, quae dies forte reve- labit."— Amoen. Acad. Vol. i. p. 186.

I

HISTORY OF ZOOPHYTOLOGY. 17

was he afterwards satisfied of the non-existence of animalcules, that he combated the opinion of those who maintained the con- trary, pointing out where the error lay in mistaking small in- sects which had crept into the sponge in search of food or shel- ter for the real inhabitants and fabricators of the zoophyte. Yet not the less was Ellis convinced of its animality ; — its chemical constituents and its structure were to him conclusive proofs of this fact, particularly when added to the signs of irritability he saw them exhibit when in a fresh state. " I am persuaded," he writes to Linnaeus, " thejihroi intertextce of sponges are only the tendons that enclose a gelatinous substance, which is the flesh of the sponge. Mr Solander and I have seen the holes or sphincters in some of our sponges taken out of the sea, open and shut while they were kept in sea- water ; but discovered no animal like a polype, as in the Alcyonium manus mortui." And again — " I attended last summer in pursuit of the animals in sponges, but believe me there are none : but the whole is an ani- mal, and the water passes in a stream through the holes, to and fro, in each papilla."*

When Ellis published these discoveries, which form in fact an epoch in the history of natural science,-}- Linnaeus was in the

• Lin. Corresp. Vol. i. p. 161 and p. 163. in a subsequent letter Ellis explains himself more fully. " I am now looking into the nature of sponges, and think by dissecting and comparing them with what I have seen recent, and with the Alcy- onium manus mortua, that I can plainly see how they grow ; without trusting to Peyssonell's account of them, which is printed in our Philosophical Transac- tions, wherein he pretends to tell you, that he takes the anirn;d out of them, that forms them ; and that he put it into them, and it crept about through the mean- ders of the sponge. This kind of insect, which harbours in sponges, I have seen ; but sponges have no such animals to give them life, and to form them. Their mouths are open tubes all over their surfaces, not furnished, like the tubes of the Alcyonium manus mortua, with polype-like mouths or suckers. With their mouths they draw in and send out the water ; they can contract and dilate them at will, and the Count Marsigli has (though he thought them plants) con- firmed me in my opinion, that this is their manner of feeding. If you observe what he has wrote on sponges in his Histoire de la Mer, and the observations he has made on the Systole and Diastole of these holes in Sponges, during the time they are full of water, you will be of my opinion. Take a lobe of the officinal sponge, and cut it through perpendicularly and horizontally, and you will observe how near the disposition of the tubes are to the figure I have given of the sec- tions of the Alcyonium manus mortua in my plate of the Sea-Pens."-^Lin. Corresp. Vol. i. p. 79-80. f The Royal Society adjudged to Ellis the Copley medal, " as the most

B

18 HISTORY or ZOOPIIYTOLOGY.

zenith of his reputation,— the "prince of naturahsts," as his followers loved to style him, — from whose decision on all disput- ed points in natural history, there was scarcely an admissible appeal. And Linnaeus almost merited this distinction, for he was a man not only of superior capacity and acquirements, of great sagacity, ready apprehension, and fruitful fancy, but he was also of a candid and liberal disposition ; and the ingenious labours of Ellis received from him great and merited commen- dation. He had previously, in the belief that lime was never formed but by animals, placed the Lithophyta in the animal kingdom ; and he now adopted the opinions of Ellis so far as to include in it the horny and flexible polypidoms also, but at the same time he broached the conjecture, for it deserves no higher praise, that these were really intermediate between the animal and vegetable kingdoms, so that it could not be said they properly belong to either. The animalcules of the Litho- phyta, like the testaceous tribes, he said, fabricated their own calcareous polypidom, forming the whole mass into tubes, each ending on the surface in pores or cells, where alone the animal seems to dwell ;* but the polypes of the proper Zoophyta, so far from constructing their plant-like polypidoms, were, on the contrary, the productions or efflorescences of it, f just as the flowers do not make the herb or tree but are the results of the vegetative life proceeding to perfection. Polypes, according to this fancy, bore the same relation to their polypidom that flowers do to the trunk and branches of the tree ; both grew by vege-

public mark that the Council can give of their high sense of the great accession which natural knowledge has received from your most ingenious and accurate investigations." The medal was delivered to him, Nov. 30, 1768, by Sir John Pringle, the President — Soland. Zooph. Introd. p. xi. See also Swainson's " Discourse on the Study of Nat. History," p. 38-9.

* Lithophyta — " animalia moUusca, composita. Corallium calcareum, fixum, quod inffidificarunt animalia aflSxa." — Syst. 1270.

f Zoophyta — " animalia composita, efflorescentia. Stirps vegetans, meta- morphosi transiens in florens Animal."— Syst. 1287. " Zoophyta non sunt, uti Lithophyta, auctores suae testte ; sed Testa ipsorum ; sunt enim corpora (uti flores) imprimis generationis organa, adjectis nonnullis oris motusque instru-

mentis, ut motum, quern extrinsecus non habent, a se ipsis obtineant." Syst.

Nat. edit. 10. 799. When Berkenhout translates the first of these delinitions

" stems vegetating and changing into animals j" Synop. i. 15, he certainly de- parts, if not from the letter, yet from the meaning of Linnaeus.

HISTORY OF ZOOPHYTOLOGY. J 9

tation, but while the one evolved from the extremities blossoms which shrunk not under external irritations and were therefore properly flowers, — the other put forth flowers which, because they exhibited every sign of animality, were therefore with reason considered animals. " Zoophyta," he writes to Ellis, " are con- structed very differently, living by a mere vegetable life, and are increased every year under their bark, like trees, as appears from the annual rings in a section of the trunk of a Gorgonia. They are therefore vegetables, with flowers like small animals, which you have most beautifully delineated. All submarine plants are nourished by pores, not by roots, as we learn from Fuci. As zoophytes are, many of them, covered with a stony coat, the Creator has been pleased that they should receive nourishment by their naked flowers. He has therefore furnish- ed each with a pore, which we call a mouth. All living beings enjoy some motion. The zoophytes mostly live in the perfectly undisturbed abyss of the ocean. They cannot therefore par- take of that motion, which trees and herbs receive from the agi- tation of the air. Hence the Creator has granted them a ner- vous system, that they may spontaneously move at pleasure. Their lower part becomes hardened and dead, like the solid wood of a tree. The surface, under the bark, is every year fur- nished with a new living layer, as in the vegetable kingdom. Thus they grow and increase ; and may even be truly called ve- getables, as having flowers, producing capsules, &c. Yet as they are endowed with sensation, and voluntary motion, they must be called, as they are, animals ; for animals differ from plants mere- ly in having a sentient nervous system, with voluntary motion; nor are there any other limits between the two. Those there- fore who esteem these animalcules to be distinct from their stalk, in my opinion, founded on observation, deceive and are de- ceived."*

There was something in this hypothesis peculiarly captivating to an imaginative mind, and few poets have possessed a richer fancy than Linnaeus. He seems to have ever fondly cherished the opinion, for in his curious Diary, in which he has enumerat- ed with much complacency all his works and merits, it is men- tioned as one of his principal recommendations to the respect

* Lin. Corresp. Vol. i. p. 151-2.

20 HISTORY OF ZOOPHYTOLOGY.

of posterity. " Linne," he says, " decided that they (zoophytes) were between vegetables and animals : vegetables with re- spect to their stems, and animals with respect to their flores- cence. This idea is still entertained."* Before we notice the manner of its reception by Ellis, we may take a short review of the writings of some other of the opponents of the latter natu- ralist.

Ellis had indeed effected a revolution in the opinions of scien- tific men, but there were some even of considerable reputation who either wavered between the old and new, or continued to hold the notions of their fathers,f which, however, very few ventured to maintain publicly. Of these the only one who merits our particular notice is Dr Job Baster of Zurichsee in Zealand, who seems to have been very imperfectly qualified for the task he had undertaken. At first he boldly asserted the vege- tability of all zoophytes, attempted to prove that the Sertulari^ were really articulated Confervse, and that the little animals ob- served on them were merely parasites, which had as little to do with the formation of the object they rested on, as the maggots in a mushroom had to do with its moonlioht growth. These the results of his actual observation were set forth in a tone of arrogance calculated to wound the feelings and good fame of Ellis, nor is this conduct to be wondered at, for ignorance is usually as unfeeling as she is proverbially confident in her as- sertions, and the Dutch naturalist was truly very ignorant of all relating to the subject he attempted to elucidate. Unskilled in marine botany he actually mistook the objects of the enquiry, and instead of Sertulariae set himself to examine true Confervae, — a fact which the drawings illustrative of his paper demonstrate. His further experiments made him fully aware of this ridiculous error ; and having become better acquainted with his subject,

Pulteney's General view of the Writings of Linnaeus, by Dr Maton, p. 560. Lond. 1805.

t Count Ginanni was one of these, and had the hardihood to question the accuracy of the observations of even Jussieu — How far he was competent to observe himself will be made apparent to the zoophytologist by the following extract : — " Loco polyiiorum Bernardi de Jussieu, papillas septem glandulis con- sitas repcrit, et mucum pulat esse, quern vocant cornua : ex papillis vero pres- sisaqua, demde lac pull ulat, eiedemque ad corticem inseparabili nexu adherent." —Hall. Bib. Bot. ii, 444.

HISTORY OF ZOOPHYTOLOGY. 21

he appears to have been puzzled what to make of zoophytes ; they were certainly not sea-weeds, — and it were too humihating to adopt a once rejected theory, — when happily the Systema Naturae came to his aid, and he instantly adopted with zeal the vegeto-animal fancy, because, he says, it illustrated in a wonder- ful manner other things which were previously obscure and in- comprehensible, and because it was in perfect keeping with the doctrine which taught that animated beings were a series of links constituting one long chain that could not be broken without violation to the continuity of organization, — the different species being so closely connected on this side and that, that neither sense nor imagination can detect the line which separates one from the other. It must be allowed that in Baster the doctrine of Linnseus has found its best advocate. He tells us that in zoophytes there are too many signs of a perfect vegetation to permit us to believe that they can owe their origin to animal- cules so minute as to require a microscope to see them, and the great simplicity of whose organization altogether unfits them for perfecting such works : and as from the law of continuity indi- cated above it was reasonable to presume the existence of beings in which the distinctions between animals and plants should meet and amalgamate, so by a comparison of their definitions it may be made obvious that these distinctions disappear in zoophytes. A plant is an organized body without sense or spontaneous mo- tion, adhering by means of a root to some foreign substance whence it derives the material of its life and increase : an ani- mal, on the contrary, is an organized body endowed with sen- sation and perception, which can, of its own free will, make cer- tain movements peculiar to itself. Like the plant, zoophytes grow fixed by a root ; and yet at the same time they are ani- mals, for they show when touched that they feel by some mo- tion, and when they perceive food proper for them they seize and devour it by the action of certain members.

Having in this manner commended the theory to our favour, and shown its reasonableness and consonance to nature, Baster goes on to explain the manner in which he conceives his ex- periments prove that the Sertulariadse or flexible corallines grow. The ova or seeds of these zoophytes, he asserts, pullulate from the body of the mother in the likeness of tender articulations

22 HISTORY OF ZOOPHYTOLOGY.

or new branches, which fall off on maturity, and adhere to any stone, shell, or other hard body, by which they are protected until the young are excluded. Now the outer coat of this egg or seed is of a vegetable nature, and it throws out from the sides in the manner of other seeds, certain little roots by means of which it remains permanently attached ; but the internal part of the egg or seed is anhnal, and growing simultaneously with its vegetable covering, it is dispersed through all the ramifica- tions and occupies their hollow interior, being developed into polypes in the lateral denticles and extreme cells. Such was the deduction he came to from observations made on the growth more especially of the Sertularia abietina, which he had kept alive for nearlv four months in a vessel of sea water. When a new part was formed, there first emerged from the stem a mi- nute tubular joint, which rose to four, five, or even eight lines in height: after some days some lesser buds, regularly dispos- ed in an alternate manner, were seen on the sides of this branch, which in the course of four or six days grew into cells contain- ing perfect polypes. Hence it is obvious to Baster that the stem of this and similar zoophytes grows in thickness and length as plants do, and that the medullary pith is animal, which it is not wonderful should assume a dendroidal form, when we see zinc and quicksilver do the same by the mere force of affinity. Trembley had already pronounced the cells of the fresh-water zoophytes (Plumatella) to be not the work of the polypes, but rather compartments in which they concealed a part of their body ; and this fact, added to those already given, makes it cer- tain that the animalcules of the Sertulariadse are entirely pas- sive, and have no more to do with their polypidoms than the flower has with the increase and growth of the herb.*

There is some ambiguity in Easterns statement of his opinions, for it is not very obvious whether he believed the new formed branchlets to be themselves the eggs or seeds, or whether they only contained the eggs ; but be this as it may, it appears scarce- ly doubtful that he knew nothing of the true ova and their cu- rious ovaries. The phenomena observed in the production of new parts are correctly stated, but nothing but wilful prejudice

* Phil. Tniiis. Vol. Hi. p. lOe-118 For Baster's woiks see Hall. Bib. Bot.

i. 4G8.

HISTORY OF ZOOPHYTOLOGY. 23

could blind him to the fallacy of the consequent reasoning. The analogy attempted to be drawn between the eggs of zoo- phytes and the seeds of plants has no existence, for every tyro knows well that the coat or skin of a seed in no instance ever pushes forth radical fibres, or ever exhibits any sign of vegeta- tion ; — it is a dead part which is cast off or corrupts, and exerts no further influence on vegetation tlian as a protection to the cotyledons and embryo which it invests, so that if it is true that the coat of the ova of zoophytes is the source of their vegetative part, as Baster says, that coat must be of a very different na- ture from the skin of seeds. It would have been better to have compared the oviform bodies of the zoophyte with the buds of the tree, and he might have disported with this fancy to some effect, for there are many analogical resemblances, and the in- applicability of the illustration is not so very plain. Still it is inapplicable, for buds grow from the absorption of water and in- organic matter which is diffused and assimilated by means of a certain determinate organization, while the covering of zoophy- tes receives no increase except through the medium of its poly- pes;— it has no sap-vessels, no spiral tubes, no cellular paren- chyma^ no absorbent roots, no pores and spiracles on the sur- face, so that all its material must be derived from an internal source ; and to say that a body vegetates when the nutriment is received and assimilated in a different manner, and by a differ- ent structure from what it is in plants, and is productive in its assimilation of opposite principles, is to use terms in so vague a sense as would be intolerable in any science.

Neither the authority of Linnaeus, nor the imperfect experi- ments of Baster, had any effect on Ellis, who steadily opposed this vegeto-animal doctrine, and whose superior knowledge made it easy for him to detect and point out the erroneousness of the observations on which it principally rested. In reference to the opinion itself he wrote to Linnaeus, — " artful people may puzzle the vulgar, and tell us that the more hairy a man is, and the longer his nails grow, he is more of a vegetable than a man who shaves his hair or cuts his nails ;* that frogs bud like trees,

* Boliadsfh in answer to those who believed that the Pennatulae were plants uses the same argument — De Anim. Mar. p. 123. This author, who wrote in ] 761, was a strenuous advocate for the unmixed animality of zoophytes.

24 HISTORY OF ZOOPHYTOLOGY.

when they are tadpoles ; and caterpillars blossom into butter- flies. These are pretty rhapsodies for a Bonnet. Though there are different manners of growth in the different parts of the same animal, which the world has long been acquainted with, why should we endeavour to confound the ideas of vege- table and animal substances, in the minds of the people that we would willingly instruct in these matters ?"* And in a subse- quent letter he repeats, " I cannot reconcile myself to vegeta- ting animals : the introduction of the doctrine of this mixed kind of life will only confuse our ideas of nature. We have not proof sufficient to determine it ; and I am averse to hypo- theses."-f-

Pallas, who published at this period an admirable history of zoophytes, :{: was also the advocate of the Linnaean doctrine, but he adduced no other facts than those furnished by Baster in its aid, — setting, however, in bolder relief, the argument de- rived from its accordance with the hypothesis of a continuous series in the structure of organized beings, which, it was for long a point of orthodoxy to believe, formed a chain " in linked sweetness long drawn out," graduating insensibly from man to the monad, — as Bonnet maintained ; or branching off into les- ser series after the manner of a tree, — a simile suggested by Pallas himself as more correctly representing the " System of Nature." § He also adopted the opinion of Baster, who in this respect continued in opposition to Linnseus, that the true corallines ( Corallina) were entirely of a vegetable nature, and his arguments on this head may be summed up as follows : In external appearance and structure a few corallines resemble some fuci, and many of them are like confervse ; they differ from other zoophytes in chemical composition, for, on being burned, they emit the smell of vegetable matter, neither do they contain a volatile salt or animal oil ; the pores observable in their calcareous portion are too small to be the habitations of po-

* Lin. Conesp. Vol. i. p. 226. f Ilji'l- P- 260.

^ " Printeps in hac classe opus." — Hall. Bib. Bot. ii, 566 § " Didicimus in Zoophytis, sic jure vocandis, vcgetabilem natunun cum ani- mali ita misceri, iit veie anceps et dubia pa&sim sit." &c. Elenc. ^ooph. Prajf. viii. The Introduction to tlie work is beaded. " Dc zoopliytoruin inttrmedia iiatura et inventione." His ideas of the Natural System are given in an inte- resting passage at p. 23-4, which is too long for quotation in this place.

HrSTORY OF ZOOPHYTOLOGY. 25

lypes, and similar pores can bo detected on fuci ; no polypes nor any visible token of life could be discovered by Jussieu in any coralline, a species of which, moreover, a Mr Meese had found growing upon a heath in Friesland ; and lastly, the fructification of corallines is very similar to that of fuci and confervas.

Were these the deductions of correct observation and expe- riment they would unquestionably have been conclusive, but some of them were already known to be contrary to the fact, and the others were weakened with doubts and uncertainties. Ellis, conscious of his superior knowledge both of marine botany and zoophytology, put forth an answer to this attack which is remarkable for clear arrangement, and for candid and honour- able bearing to his opponent, who had scarcely deserved this at his hand. * Having shewn that the presumed coralline which Pallas had compared to a fucus or sea-weed, was in fact a fucus, Ellis proceeded to prove how widely different every coralline was in structure and texture from any confervae ; and that the former, contrary to Pallas's assertion, not only gave out when burned " an offensive smell like that of burnt bones or hair," but afforded also on careful analysis both volatile alkali and em- pyreumatic oil. -|- " Dr Pallas," Ellis continues, " proceeds to prove that corallines cannot be animals, as the pores of their calcareous substances are too minute for any polypes to harbour in. These words of the Doctor's seem to imply, as if the coral- line substances were only habitations for detached polypes, and not part of the animals themselves. How this affair stands, I hope to have clearly demonstrated long before this, for I have plainly seen, and endeavoured to shew mankind, that the softer and harder parts of zoophytes are so closely connected with one

" It appears from the Lin. Corresp. Vol. i. p. 18G, that Pallas had written disrespectfully of Ellis. In his Elen. Zoophytorum the latter, however, is pro- fusely complimented : — " Ellisium subtilitate atque acumine observationum om- nes super eminentem," — Pnef. p. x. — is praise enough surely, but its sincerity might be questionable.

"I- This character, as Lamouroux remarks, is insufficient, seeing that the major part of marine plants give out, in burning, odours and products analogous to those of animals — Cor. Flex. p. 12. It is now well known that chemistry affords us,

in its minute analyses, no test between animal and vegetable matter See Prout's

Bridgewater Treat, p. 415, and more particularly Ticdemann's Comp. Physiolo- gy, p. 48, &c.

26 HISTORY OF ZOOPHYTOLOGY.

another, that they cannot separately exist, and therefore have not hesitated to call them constituent parts of the same body, and that the polvpe-like suckers are so manv mouths belon^infir thereto.

" Now, forthesmallnessofthe pores, which the Doctor has men- tioned here (among the Corallines) to be a contradiction to ani- mal life ; he certainly has forgot one circumstance, when he in- troduces the CoralHum pumiluni album, (Essay Cor. t. 27. f. c.) or his Millepora calcarea (Pall. Elench. p. 265,) as an animal, which is, that he there says, it has absolutely no pores at all.

" As there can be no doubt, but every part of what is called Coralline is necessary to make out such an animal, or beinof, it will be very difficult, if not almost impossible, to determine the proportion there ought to be between softer and harder parts ; and therefore it cannot be thought unreasonable to say, that in some of this tribe the stony parts are by much the greater part of the whole, especially as Doctor Pallas's objection can be only against the crust, or lapidescent part, as the inside of many of them is far from being hard, being exactly like a Sertularia, so that I do not know if it would not be a good definition to one well acquainted with that tribe to say, a Coralline is a Sertula- ria, covered with a stony or calcareous crust ; if the mouths should happen to be very small, their number may make up that deficiency. We see in the greatest number of corallines their surface full of holes ; we saw the same in Escharas and Mille- poras thirty years ago ; since that time magnifying glasses have been improved, so as to shew us, that they are all orifices for polype-like suckers ; why should not we now admit that glasses may be still more improved, so as even to make us able to see what may be the intention and use of these minute orifices, which according to all rules of reasoning, we must suppose to approach in nature to them they are most alike. From this extreme mi- nuteness then of the pores of these Milleporse, confessed to be zoophytes, as well as those of Corallina officinalis as before men- tioned, it is no great matter of surprise, that Doctor Jussieu could not perceive any animal life in the corallines, nor Doctor Schlosser in the JMillepora calcarea. As these experiments ought to be attended with manv convenient coincidinof circum- stances that do not often happen to persons who only go to the

HISTORY OF ZOOPHYTOLOGY. 27

sea side, perhaps for a few dajs or hours, so that it is unreason- able to conclude, because they have been unsuccessful, that more accurate observers may not be more fortunate at another time." — Having thus disposed of an argument which he could not distinctly answer, Ellis goes on to notice the fact of the co- ralline which had been found on Beroummer heath in Fries- land, and which the vagueness of the manner in which the dis- covery was announced permitted or warranted him to ascribe to accident ; and he then concludes his admirable essay with a faithful and minute account of the fructification of the confervse, and proves to a demonstration that when Baster and Pallas at- tributed a similar fructification to corallines, they had very er- roneous ideas of the subject,*

The discussion rested here, and zoophytes, including the sponges and corallines, have been ever since enumerated among the subjects of the animal kingdom, although some, among whom Spallanzani may be particularized, continued in the belief that the corallines and the sponges were vegetables. But naturalists continue to be divided in opinion relative to the nature of acknow- ledged zoophytes, for many, of whom Bory de St Vincent may be considered the chief, -f- still speak of them as intermediate beings partaking of a twofold nature; while others, under the leading of Lamarck, defend their claims to pure animality. No new doctrine has been promulgated ; neither indeed have the old been defended or attacked by any other facts or arguments than those already referred to, and with these before me I cannot hesitate to give my assent to the opinion of Ellis. No one denies that the polypes considered abstractedly from their polypidoms are really animals ; — their quick and varied movements, — their great irri-

■ Phil. Trans. Vol. Ivii. p. 404, &c Pallas appears to have been con- vinced by this essay that the Corallines were animal ; and he acknowledged that in reference to the land species he had been imposed on. — Lin. Corresp. i. 227, and 568. Yet it should be remembered that Captains Vancouver and Flinders observed on the shores of New Holland, at considerable heights above the level of the sea, arborescent calcareous productions which they considered to be corals. Peron says they are either corals or vegetables incrusted with calcareous mat- ter; and Dr Clarke Abel has proved that they are the latter — Edin. Phil.Joum. u. 198.

f Encyclop. Method, ii, 647 — Cuvier in an early work gave countenance to this opinion, but in his Regne Animal, iii, 220, Paris, 1830, it is repudiated.

28 HISTORY OF ZOOPHYTOLOOY.

lability, — the existence of a mouth and stomach, — the nature of their food, its digestion, and the evomition of the indigestible remains are incontestible proofs of this ; — and it seems impro- bable, to say no more, that this animal should be fitted round with a case that grew independent of it and from a different cause. And the case itself has no analogy, as Ellis shewed very clearly, either to bark or to wood : it possesses the structure of neither of them, nor is it formed in the same manner by the addition of concentric layers, nor does it contribute to the formation of new parts, but, like the shell of testaceous mol- lusca, it is extravascular, and when once formed suffers no other change than what external injuries or time may operate. If possible its coincidences with the skin of cellular plants are even fewer : the one is a living part which has very important functions to perform in relation to the plant itself and to the at- mosphere or circumfluent medium in which it lives ; the other exhibits no action characteristic of life, and is nothing more than a condensed albuminous or calcareous sheath, appropriat- ed solely to support or protection.*

But although I aorree with the advocates of the animalitv of zoophytes in general, I cannot go the length of Ellis in consi- dering it proved that sponges and corallines belong to the same class. Ellis, we have seen, knew that no polypes were to be found in sponge, and their existence in the pores of corallines was inferred merely from the structure of these and their chemical composition. They have been examined by subsequent natu- ralists fully competent to the task, and under the most favour- able circumstances, — in particular by Cavolini and Schweigger, — and the result has been a conviction that these productions- are truly apolypous. Now this fact, in my opinion, determines the point, for if they are not the productions of polypes, the zoolo- gist who retains them in his province must contend that they are individually animals, an opinion to which I cannot assent, see-

* I do not enter into the question whether the Confervae are real animals or not, because, whatever conclusion we might adopt, they would not come within our definition of a zoophyte or polype, since they assuredly have neither mouth, tentacula, nor stomach. Nor need I discuss the propriety of instituting, with Treviranus, a fourth kingdom of animated nature, composed of the zoophytes and aquatic cryptogamia, as my object and plan is only to dcscrihe what have been almost universally considered zoophytes.

HISTORY OF ZOOPHYTOLOGY. 29

iiig that they have no animal structure or individual organs, and exhibit no one function usually supposed to be characteristic of that kingdom. Like vegetables they are permanently fixed, — like vegetables they are non-irritable, — their movements, like those of vegetables, are extrinsical and involuntary, — their nu- Iriment is elaborated in no appropriated digestive sac — and like cryptogamous vegetables or algae they usually grow and ramify in forms determined by local circumstances, and if they present some peculiarities in the mode of the imbibition of their food and in their secretions, yet even in these they evince a nearer affinity to plants than to any animal whatever.

30 STRUCTURE AND PHYSIOLOGY

CHAPTER II.

On the Structure and Functions of the Polypes abstractedly considered.

On the continent the term Zoophyte has of late been used in a very extensive sense, so as to include every animal which ex- hibits a circular disposition of parts radiating from a common centre, and many also in which this character is little or not at all obvious. In this country the word has never been so em- ployed excepting in translations from a foreign language : no English writer ever thinks of calling an intestinal worm, or a sea-jelly, or a star- fish, or even the infusory animalcules, a zoo- phyte ; but he applies the name to no other creatures than those which in their form, or most remarkable characters, recall the appearance of a vegetable or its leading properties. In this restricted sense I also use it in this work, or rather with a still narrower circumscription, having assigned what appear to be sufficient reasons for removing the corallines and sponges from the category, and restoring them to the vegetable kingdom, to which the earlier naturalists believed they had a rightful claim. The definition of a zoophyte is thus considerably simplified, but there remains sufficient variety and discrepancy in the consti- tuents of the order to render that definition in some degree vague and incongruous. The fact is — the classification of molluscous, and radiated, and acritous animals requires to be recast : the limits between them have not been determined with undisputed precision, and it seems probable that there are in each class some tribes which will pass from one to the other as discovery pro- ceeds. It has been recently proposed* to remove a large pro-

* Thompson's Zoological Researches and Illustrations, p. 92.

OF POLYPES. 31

portion of zoophytes hitherto considered legitimate subjects of their order to the molhisca, which, about the year 1815,* had received a considerable accession to its numbers from the same source; but so far from acknowledging the propriety of the pro- posed translation, I incline to agree with Lamarckf, that it would be better to separate again the colonized zoophytes from the mollusca, and form with them, and with such zoophytes as have an analogous organization, a distinct class, to occupy the wide interval between the molluscan and radiated types, allied to the former by the non-symmetrical figure of the body, and to the latter by the circularity of the oral members. It is, however, unnecessary to enter here upon this discussion, for my intention is to describe what are usually reckoned zoophytes, without having regard to the naturalness of the group considered as a whole, and with this view I adopt the class as it was long ago established by Solander and Ellis, excepting only the corallines and sponges, which will form the subject of separate monographs. The following definition may serve to characterize the class :

Animals avertebrate^ inarticulate, soft, irritable and contrac- tile, loithout a vascular or separate respiratory or nervous sys- tem : mouth superior, central, circular, edentulous, surrounded by tubular or more commonly by Jilifurm tentacula ; alimentary ca- nal variable, — where there is an intestine the anus opens near the mouth: asexual; gemmiparous : aquatic. — The individuals (Polypes) of a few families are separate andperfect in themselves, hut the greater number of zoophijtes are compound beings, viz. each zoophyte consists of an indefinite number of individuals or polypes organically connected and placed iv a calcareous, horny or membranous case or cells, forming, by their aggregation, corals or plant-like Polvpidoms.

In this definition there are two parts which require our par- ticular attention — the Polype whose presence is essential, and the Polypidom,X which is the house or support of the polype,

* Savigny's Memoires sur les Animaux sans Vertebres. Seconde Partie. Pa- ris, 1816, 8vo.

f Hist. Nat. des Anim. s. Vert. iii. 82 — 87.

\ I borrow this term from the translator of Lamouroux's work on Corallines. The Rev. Mr Kirby, in his Bridgewater Treatise, uses the word Pohjpary to ex- press the same thing. Both of them are translations of Puhjpier, a word in- vented by Reaumur, and now in general use among the French naturalists.

32 STRUCTURE AND PHYSIOLOGY

and which, though commonly present, is yet not necessary to the existence of a zoophyte. To the structure and functions of the former I hmit myself in this chapter ; and should the reader find the outhne given in relation to some of the families too slight and sketchy, I may advertise him that he will find it filled up with greater detail in the observations which it is in- tended to prefix to each separate order.

The description usually given of the structure and functions of polypes in general has been derived principally from an ex- amination of the Hydra— a naked species which inhabits ponds and ditches. A polype is thus represented as being a somewhat globular or cylindrical body of small size, of a homogeneous gela- tinous consistence, and very contractile, in the centre of which there is excavated a cavity ^for the reception and digestion of its food. The aperture to this cavity is placed on the upper disk of the body, and is encircled by one or two series of filaments or tentacula which are used to capture the necessary prey, and bring it within reach of the lips ; while the opposite end serves the purpose of a sucker to fix the creature to its site, or being- prolonged like a thread down the hollow sheath, to connect it with its fellow-polypes of the same polypidom, which by this means become compound animals, " the whole of whose parts are animated by one common principle of life and growth." There are no organs of sense, no limbs appropriate to locomo- tion, no circulating vessels, no nerves, nor lungs, nor gills, no chylopoetick viscera, nor intestine, for there is " but one con- duit both for purgation of their excrements, and reception of their sustenance ;" and when to these negations there is to be added the want of generative organs, a being of simpler organi- zation than the polype can scarcely be conceived ; and, perhaps, it is actually the simplest, for the infusory animalcules which had been placed underneath them in the scale of organization, are now known to possess a much more complex structure.

Such is the idea of a polype we obtain from the writings of Ellis, and the description of its general structure given by La- marck,* after an interval of seventy years, is identically the

* Anim. s. Vert. ii. 10. Bosc, Vers, ii. 216— Lamouroux in 1810 and 1812 bad indeed asserted that the polypes with polypidoms coidd not, hi relation to their structure, be compared mth the fresh-water hydra, but that they approxi-

OF POLYPn:S. 33

same. Some few species, classed by the predecessors of the latter among zoophytes, had in the meantime been ascertained to be differently constructed, and furnished with less simplicity, but being in consequence removed into a different category, they were not allowed to disturb the received opinions on polype ana- tomy. Still more recent discoveries have shewn, however, that these are very erroneous, and that the animals of even our na- tive polypidoms form at least two classes distinguished by a very remarkable dissimilarity of organization. By the one they are allied to the tunicated and acephalous mollusca, more especially to the compound families of the former, and hence may be de- nominated Ascidian polypes ; by the other they form a link of the chain or circle which associates the radiated animals, and, assuming the hydra for their representative, we shall call them Hydraform polypes.

The ascidian polypes never occur in a separate and naked form, but are always placed within the cells of a polypidom of a calcareous, membranous, or fibro-gelatinous consistence. The form of the cells in many genera, as Eschara, Flustra and Cel- lepora, suggests a belief that their tenants, although arranged in a close and determinate manner, are each separate from their neighbours and complete in themselves, — an opinion that is held by some of our best naturalists ; but the observations of Dujardin on some allied fossil polypidoms, render it very pro- bable that there are pores of communication between the cells;* while those made by Professor Grant seem to have proved that the polypes of the Flustra are connected together by a living axis, and are hence truly compound beings. Since the Vesiculi- fera also, which are admitted to be composites, belong unques- tionably to this remarkable form of animated entities, it is safer,

mated nearer than was believed to the mollusca, of which they might at some future time be considered a family. The opinion certainly rested on few and hasty observations, and no anatomical details were given in its support. See his Edit, of Soland. Zoophyt. pref. p. vii. For example, he not only recognizes a relationship between Lobularia and Actinia, but he tells us that the polypes of the FlustriB, Cellariie and Sertularioe are similar to those of Lobularia ! Coral. Flex. p. 332. Such loose observations as these are, have no influence on the progress of discovery. The observations of Savigny were evidently more spe- cific and correct ; but I am not aware that the details have been yet published. — See his Mem. sur les Anim. s. Vert. ii. p. G5. * Blainville's Actinologie, p. 675.

C

54

STRUCTURE AND PHYSIOLOGY

for the present, to consider all the ascidian as compound poly- pes.* T'here is nevertheless a remarkable difterence between them and the hydraform tribes in their mode of composition. In the latter the polypes are simply developements of the com- mon central fleshy mass, identical with it in structure and tex- ture ; in the former each individual is a distinct organism, and the medium which binds them together, whether vascular or li- gamentous, has its own peculiar character. The one we may compare to a chain of which all the hnks are welded,~the other to a necklace where the beads are strung together by a percur- rent thread. To express this distinction we shall call the hydra- form compound polypes, and the ascidian aggregated polypes.

The body of the ascidian polypes is lengthened, somewhat cylindrical or at times bulged at the base, and when at rest lies, in the form of a syphon, doubled up upon it- rig- ^'

self in the cell, (Fig. 2, \) to which it is con- nected by a tendon at the bottom, and by the duplicature of a thin membrane round the aperture, so that it is impossible it should ever voluntarily leave the cell to swim at large, as Baster and others have maintained. The head or upper end is surrounded by a single row of tentacula, (Fig. 3, «,) which are solid, filiform and non-contractile, for the animal can only shorten them, excepting to a slight extent, by rolling them up in a spiral manner: they are apparently smooth, but with a high mag- nifier it is ascertained that they are clothed with numerous fine cilia, % which are in ceaseless motion, and are supposed

* " The polypi are most intimately and inseparably connected with the axis by three parts of their body, and are only digestive sacs or mouths develoj.ed by the axis, as in all other zoophytes, for the nourishment of the general mass. By the axis of a zoophyte, I understand every part of the body excepting the polypi, whether of a calcareous, horny, or fleshy nature. The exact mathemaUcal ar- rangement and forms of the cells of Flustrs is incompatible with their existence as separate and independent beings, but is quite analogous to what we are ac- customed to observe in C'ellaria., Sertulan^e, Pluniularia^ and many other well- known compound animals."_Grant in Edin. New Phil. Journ. m. lib. ^ee also Blainville, Man. d'Actiiiologie, p. 99.

t The figure, for which I am indebted to my friend Mr William Scott, repre- sents the polypes of Flustra membraiiacea in a state of retraction.

\ For a history of this discovery, written with great learning and impartiality.

OF POLYPKS.

35

to perform the office of breathing organs by keeping up a constant current of water along their surfaces, which sets in towards the mouth in an invariable direction ; i'ig- 3.

and from tlie incessant revolution of particles within the mouth and the gul- let, observed by Professor Grant, this oro-an seems to be also ciliated internal- ly. The more especial use of the ten- taculais to arrest the prey which chance floats within their reach and conduct it to the mouth, — a simple aperture pla- ced in the centre of the tentacular cir- cle, and which is armless, having in no instance either jaws or teeth. It is the entrance into a long membranous gul- let (5,) of ))erfect transparency, and which can be traced through its equally transparent envelope, to its termination in a somewhat globular and comparatively large organ placed near the curvature of the body, and render- ed opaque partly by the greater thickness and fleshiness of its structure, but perhaps more so by the nature of its contents. This is the stomach (c,) and from the side of it there proceeds a narrow intestine {d,) which follows a straight upward course along the side of the gullet, and opens at the aperture of the cell by a separate orifice, from which the undigested remains of the food are ejected. There is another organ of a roundish figure appended to the bend of the intestine, which is supposed by some to be an ovarium (e,) but it seems not unnecessary to remark, that this appropriation of it to the generative function has perhaps no better proof than what is derived from a similari- ty of position between it and the supposed ovarium of the com- pound mollusca. It is, I presume, the organ which Blainville says he is vvilling to believe performs the functions of the liver,* an opinion in which I am disposed to concur.

see Dr Sbarpey's article " Cilia" in the Cyclopsedia of Anatomy and Physiology,

Vol. i. p. 609.

" Manuel d'Actinologie, p. 72. — In the Actiniae, Blainville adds, it is almost certain that there is no Liver ; nor in the Hydraform polypes ; but in the Pen- natulae " disseques vivans ou tres-frais, on remarque, dans les parois memes

du corps do I'estomac, des rangces d'organes en forme de petites taches jaunatres,

36 STRUCTURE AND PHYSIOLOGY

No trace of a nervous or vascular system of any kind has been detected, nor is there any organ of sense, but the polypes are notwithstanding very sensible of external impressions. * When left undisturbed in a glass of fresh sea water, they push their tentacula beyond the mouth of the cell by straightening the bo- dy ; and then expanding them in the form of a funnel or bell, they will often remain quiet and apparently immoveable for a long time, presenting a very pretty and most interesting object to an observer of " the minims of nature." If, however, the water is agitated they withdraw on the instant, probably by the aid of the posterior ligament or muscle ; — the hinder part of the body is pushed aside up the cell, the whole is sunk deeper, and by this means the tentacida, gathered into a close column, are brought within the cell, the aperture of which is shut by the same series of actions. The polypes of the same polypidom often pro- trude their thousand heads at the same time, or in quick but ir- regular succession, and retire simultaneously or nearly so, but at other times I have often witnessed a few only to venture on the display of their glories, the rest remaining concealed ; and if, when many are expanded, one is singled out and touched with a sharp instrument, it alone feels the injury and retires, with- out any others being conscious of the danger, or of the hurt in- flicted on their mate.

Of the anatomy of the hydraform polypes a sketch has al- ready been given in the beginning of this chapter. They differ from the ascidian in their figure, which is somewhat globular or cylindrical and straight ; in the position of the body, which is vertical ; in the homogeneity of their composition, which is a semitransparent glairy gelatine, full of microscopic coloured granules ; -f- and very remarkably, in being contractile at every

que je regarde comme analogues au foie." — Fig. 2 represents the polype of Vesicularia imbricata highly magnified. It is copied from Thompson's Zool. HI. Memoir v. pi. i. fig. 4.

' " But as we perceive, in these animals, phenomena which take place by the medium of nerves in animals of a more elevated order, that is to say, sensi- bility and voluntary motion, it is not inijjrobable that in them the nervous sub- stance is mixed with their gelatinous or mucous mass, without being demonstra- ble as a particular tissue." — Tiedemann's Comp. Phys. p. 64.

t Trembley having ascertained that the coh)ur of the polype resides in these granules, and that it varies with the quality of their food, of which the nutritive part or chyme passes first into the granules of the stomachal cavity and then

OF POLYPES.

37

point, so that they can change the figure of their bodies from a globe to a cyhnder, or distort it with strictures, and can shorten and extend the tentacula at will, sometimes to an extent which is astonishing, although nothing like muscular tissue can be de- tected in their structure. * When therefore they have occasion to conceal themselves within their cells, they are not necessitat- ed, like the ascidian, to bend the body in order to obtain suffi- cient space for the tentacula, but they shorten the body and the tentacula at the same time, causing the one to assume a more globular form, and the other to dwindle down to mere knobs or

Fig. 4.

^ /tp I

papillae (Fig. 4.) -f- The tentacula, even when fully extended,

gradually into those placed more towards the surface, infers that they are a kind of glands or rather vesicles, which have the power of sucking in and again tran- spiring the nutritive fluid — Hist, des Polypes, p. 132. Lamarck adopts this opinion, Anim. s. Vert. ii. 9, which is probably correct, but it ought to be remem- bered that it is somewhat hypothetical. Consult in relation to this subject Ro- get's Bridgewater Treatise, Vol. ii. p. 77-8, Carus's Comp. Anat. Eng. Trans. Vol. i. p. 2.5, §. 23; and the reader will find Edwards' and Dutrochet's opinions on the nature of the elementary corpuscles in Bostock's Elementaiy System of Physiology, Vol. iii. p. 348 et seq. Tiedemann sums up our actual knowledge in the following sentence. — " In animals of a simple structure, polypi, entozoa, and some others, in which no vascular system for the movement of the humours has hitherto been discovered, the nutritious assimilated liquid passes directly into the parenchyma of the body, with which it enters into combination." — Comp. Physiology, p. 35.

* Trembley, Mem. pour I'hist. des Polypes, p. 25. Carus' Comp. Anat. i. p. 43. — Mr Lister, however, says that " in the substance of the necks of the polypi (of Sertularia pumila,) transverse lines were visible, bearing a resemblance to those characteristic of voluntary muscles in the higher animals ;" but we may doubt whether they are truly muscular, for this accurate observer shortly after acknowledges, that " nothing like muscular contraction was seen in the pulp of this (Plumularia setacea,) or any other species." — Phil. Trans. 1-334, pp. 371-372.

f The figures represent Hydra viridis in various attitudes and states.

38 STRUCTURE AND PHYSIOLOGY

have not the same appearance, — they taper a little, and are roughened with minute wart*=; generally arranged in an imper- fectly verticiliate fashion ; and in their evolution they are less re- gularly campanulate, one or more being usually in action and movincr from the outline of the circle. The stomach is not a distinct sac, but a simple cavity towards the centre of the body, " neither figured nor limited by particular membranes," and from which the indigestible remains of the food are ejected at the same aperture by which it had entered, for the aperture in the base of the stomach or intestine seems to be appropriated to other offices. And in reference to its relation with the poly- pidom there is this difference, — the hydraform polype is not connected with the cell by any membrane or ligament, hut ra- ther sits free within its miniature cup, retained there only by the gelatinous living pedicle which is prolonged from its base down the sheath, and binds all the polypes of the polypidom in one sympathizing family.

But this description is applicable only to the Hydra itself, and to those compound species which tenant the cups of the plant-like polypidoms embraced in the order Zoophyta hydroida. The polypes of the Asteroid zoophytes, although evidently mo- delled on the same type, have made considerable advances to- wards complexity of organization, and their relation to the poly- pidom is entirely altered. Hitherto the polypidom has been, what its name imports, a cell for retreat in danger, and in ordi- nary an extravascular insensible sheath to protect the contained animal from the rude contact of the circumfluent element; but now we find it occupying an internal position, and instead of a covering it has become a sort of prop or skeleton to a fleshy crust in which the polypes are immersed. In the Alcyonium this interior support is scarcely to be recognized in some cal- careous snicula scattered throuoh the central mass, but in Pen- natula it forms a bone stretched like a vertebral column from one extremity to the other, and in Gorgonia it is ramified into branches after the manner of a tree. It is this axis, under what- ever shape it appears, which is the true analogue of the polypi- dom of the ascidian and hydraform polypes, although the name certainly has no suitableness here, for the polypes not only cannot nestle in that which is uncellular, but they have no immediate

OF POLYPES.

39

connection with it. They, as ah-eady mentioned, are found Iodised in a sort of Fig. 5.

cell (Fig. 5. a.) exca- vated in a sarcoid crust, which constitutes the main bulk of the po- Ivpiferous mass, and which, in fact, is no- thinof more than a mo- dification of the bases and outer skin of the polvpes hardened by a deposition of calcareous granules and spicula, and made more coria- ceous in texture, to bear with impunity^the contact and ruffling of the water.* This crust is accordingly a living irritable struc- ture, permeated by tubes prolonged from the polypes and by capillary canals, for the conveyance of water and nutriment to

every part.

The connection between the crust and the polypes is there- fore of the most intimate kind, and if for conveniency the latter are separately described, the reader should ever remember, that this separation is a forced and artificial one. An asteroid po- lype mass is known by the orifices of the cells forming on the sur- face a mark more or less resembling a star, as commonly repre- sented in maps— hence the name of the order: when the polype is

* " Lorsqu'on observe les Alcyons dans leiir etat naturel, la ligne de demarca- tion entre ces deux parties parait bien tranchie, et on pouvrait au premier abord, croire ces petits animaux loges dans des cellules au pourtour de rouverture des- qnelles ils adhereraient ; mais quand on eleve a I'aide d'un acide etendu d'eau, le depit calcaiie dont la base du polype est environee, on voit qu'il y a entre ces parties continuite organique, et que la ceUule polypifere n'est autre chose que la portion inferieure du corps du polype qui, en se contractant, rentre e,, luimeme, comme nous I'avons deja vu pour les Alcyonides. Le polypier com- mun n'est en effet autre chose que la rcsultat de I'aggregation intime de la por- tion basilaire des polypes." Milne- Edwards in Ann. des Sc. Nat. iv. 336. an 1835. The student may compare this with Lamouroux's description of the Gor- gonia. Corallina, j). VJH.

40 STRUCTURE AND PHYSIOLOGY

protruded from this cell the body has a cylindrical figure, its upper disk surrounded by eight short pectinated hollow tenta- cula, in the centre of which the mouth is situated, leading into a distinct stomach, which is as it were suspended in the centre, and sustained there by eight thin membranous septa, which, stretched between the outer surface of the stomach and the in- ner surface of the external tunic, divide the intervening space into eight equal compartments. The base of the stomach is perforated like the mouth, and from the margin of the aperture depend eight white tortuous filaments, which hang, either loose or connected to a continuation of the membranous septa, in a wide abdominal cavity, immediately underneath the stomach. This cavity is again continuous with a tube which penetrates the common mass, communicating freely bv anastomoses with the tubes of other polypes, and with a fine net-work of capilla- ry vessels, formed in the spaces between them, by means of small apertures in their walls. ( Fig. 5. *) In this manner there is effected a very free communication between the individuals of each common mass, so much so, that the water swallowed by iiny one polype of it rapidly permeates the whole, -f- By tra- cing the course of the fluid we may obtain a clearer view of the organization. The water then enters the mouth, and passes through the cylindrical gullet and stomach into the abdominal cavity ; thence part of it, flowing through the canals formed by the septa stretched between the stomach and outer tunic, passes into the tentacula with whose cavity the canals are con- tinuous, and by means of small apertures in the sides of the hollow tentacula, the water penetrates and unfolds the cilia, with which these tentacula are fringed. By the distension from the water thus introduced, the body of the polype and its ten- tacula are forced beyond the surface, and every organ fully dis- played. Another portion of the water in the abdominal cavity passes into the tube continuous with it, fills it and the others in connection with it, and by means of holes in their parietes finds access into the intermediate capillary net-work, so that the whole mass is permeated with the fluid, and all and every

* A longitudinal section of Aleyoiiium tligitatum.

-f- Milne- Edwards has proved this by a decisive experiment — Ann. dcs Sc. Nat. iv. 3:28, and 338, an. 18.3.5.

OF POLYPES. 41

portion distended to a bulk which may be more than double of that which it had previous to the introduction of the fluid, and which it resumes when, from the application of irritants, the polypes contract themselves, and by their contractions force out all the imbibed water.— The tortuous filaments suspended from the base of the stomach have been generally taken for ovaries, but the observations of Dr Grant and M. Edwards seem to have disproved this opinion. The latter of these eminent na- turalists believes them to be analogous to the biliary canals of

insects. *

The affinity in structure between the asteroid zoophytes and those which we name helianthoid, from their resemblance to some compound flowers, is evident, although in the latter there is a still further recession from the simplicity of polype anatomy . We find in them a mucous coat covering the surface, — beneath it a layer of transverse submuscular fibres, while the body is sup- ported by numerous strong cartilaginous lamellse arranged in longitudinal parallelism. Each of the lamellae is attached in- feriorly to the circular layer which constitutes the base of the animal, and divides into three fascicles,— one which goes to the stomach and to the rim of the oral aperture, — another to the roots of the tentacula,— and the third is prolonged to the outer labial border, where it is bent back to form its free margin, f The stomach has its distinct and proper parietes ; there are special organs for the developement of the reproductive gemmae ; and even some traces, as is asserted, of a nervous system ; while the numerous tentacula are perforated like canals, in order that the water of respiration may be introduced into the interior, and the nutritive fluids more thoroughly influenced by its oxygen.

It has been mentioned already that there is no proper circu- lation— no movement of a fluid analogous to blood in appropri- ate vessels — in any zoophyte, but in many of the hydroida it has been discovered that there is a continuous and uniform cur- rent of a fluid, containing granular bodies which have them- selves a rotatory motion, within the tubular portions of the horny polypidom. Cavolini first detected this sort of circulation, which

* Ann. des Sc. Nat. iv. 331 ; an. 1835. f Blaitiville, Man. d'Aftinologie, p. 68.

42 STRUCTURE AND PHYSIOLOGY

is very similar to what has been observed in the Chara and other plants, in the Sertularia; and recently Mr Lister has confirm- ed this discovery, and ascertained the existence of the same phenomenon in almost all the genera of the order. 'J he result of his curious observations is thus summed up by Dr Roget. " In a specimen of the Tubularia indivisa, when magnified one hundred times, a current of particles was seen within the tubular stem of the polype, strikingly resembling, in the steadiness and continuity of its stream, the vegetable circulation in the Chara. Its general course was parallel to the slightly spiral lines of ir- regular spots on the surface of the tube, ascending on the one side, and descending on the other ; each of the opposite cur- rents occupjing one-half of the circumference of the cylindric cavity. At the knots, or contracted parts of the tube, slight eddies were noticed in the currents ; and at each end of the tube the particles were seen to turn round, and pass over to the other side. In various species of Sertularise, the stream does not flow in the same constant direction ; but, after a time, its velocity is retarded, and it then either stops, or exhibits irregu- lar eddies, previous to its return in an opposite course ; and so on alternately, like the ebb and flow of the tide. If the cur- rents be designedly obstructed in any part of the stem, those in the branches go on without interruption, and independently of the rest. The most remarkable circumstance attending these streams of fluid is, that they appear to traverse the cavity of the stomach itself, flowing from the axis of the stem into that organ, and returning into the stem, without any visible cause de- termining these movements." *

The power which sets in motion and maintains this current is yet undiscovered. Professor Grant asserts that it depends on the action of minute vibratile cilia, — " the common agents of all analogous movements in the lowest tribe of animals, ""f* — but no direct observation has confirmed this explanation, which, it will be observed, is founded on analogy only, and it has this in opposition — that the non-existence of cilia in the external or- gans of the zoophytes in question has been distinctly proved.

* Bridgew. Treat. Vol. ii. p. 233. See also Tiedemann's Comp. Pliysiol. p. 150, Ent. Mag. Vol. iii. p. 174: and Grant's Outlines of Comp. Anat. p. 429-30.

t Oiitliiu's ()(' Coinj). Aunt. p. 430.

OF POLYPES. 43

As to the purpose of the circulation in the animal's economy, it appears, from the experiments of Mr Lister, " to be the great ao-ent in absorption, and to perform a prominent part in the ob- scure processes of growth; and its flow into the stomach of the polypi seems to indicate that in the very simple structure of this family it acts also as a solvent of the food.— The particles car- ried by it," continues Mr Lister, " present an analogy to those of the blood in the higher animals on one side, and of the sap of vegetables on the other. Some of them appear to be deriv- ed from the digested food, and others from the melting down of parts absorbed ; but it would be highly interesting to ascer- tain distinctly how they are produced, and what is the office they perform, as well as the true character of their remarkable acti- vity and seemingly spontaneous motions ; for the hypothesis of their individual vitality is too startling to be adopted without good

evidence."*

'Ihis sort of circulation is not to be confounded with those aqueous currents which flow over the surfaces of the external organs of the ascidian polypes.f It has been already stated

* Phil. Trans. 1834, p. 377.

f Dr Grant repeatedly asserts that the tentacula of the hydraform polypes are also ciliated, and I would not have dared to controvert this statement, although my ov.-n observations had long ago satisfied me of its incorrectness, had it not been at variance with the observations of others who have especially directed their attention to the subject Raspail states that he was not able to discover anything analogous to cilia on the tentacula of the Hydra, ( Org. Chem- p. 293 ;) and Dr Sharpey says, that in the form of polype " which exists iu most true species of Scrtularia, Carapanularia, and Plumularia, and in aUied genera, the tentacula or arms are destitute of cilia, and incapable of giving an impulsion to the M>«<e»-."— Cyclopedia of Anat. and Physiology, Vol. i. p. 611. The observa- tions of Mr Lister are equally decisive. Phil. Trans. 18-34, p. 377.

Raspail maintains that there are really no cilia, but that the appearance of them is occasioned by currents of fluid aspired or drawn to and within the body, and expired or driven from it, and these currents are said to be produced by the difference of temperature between the fluid in the body and exterior to it. " A happy conjecture led me to consider these vibratory cilia as being mere- ly streams of a substance either inspired or expired, but at any rate of a diflfe- rent density, and consequently of a different refractive power from the surround- ing medium." P. 293 " The cilia of a respiratory organ are, then, the effect

of a diflTerence of density between the water expired, and that in which the ani - mal swims. Now there is no difficulty in admitting that, since caloric is disen- gaged in the respiration of animals of a supeiior order, it may also be disengag- ed, although, if we may so speak, in a microscopic proportion, during the act of

44 STRUCTURE AND PHYSIOLOGY

that innumerable cilia or miniature lamellae clothe the surfaces of their tentacula, and by their rapid vibrations drive a constant equable stream of water along one side, which returns along the other in an opposite direction : and by this means the purposes of respiration are effected, and the nutrient fluid fitted for assimila- tion with the body. The cilia, to adopt the language of Pro- fessor Grant, " are disposed and moved in such a manner as that the streams which they produce in the surrounding water are driven along the one side of the tentaculum from the mouth of the polypus, and on the other side of the tentaculum always towards the mouth of the polypus. And we never find that di- rection of their motion reversed, or that direction of the cur- rents changed, by which their respiration is effected and their food obtained. They are vibratile on the arms of most of the lower zoophytes, as sertularise, plumularise, serialarise, cellarise, flustrse, alcyonia, which keep their arms stiffly out in a regular cam- panulate form, while the currents flow to their mouth. When we watch the sides of the tentacula of these animals with atten- tion, and by the aid of powerful glasses, we see the extreme ra- pidity of the movements, and the remarkable regularity of the form, disposition, and motions, of those singular vibratile bodies. From the number of them, exceeding sometimes 400,000,000 in a single animal, it is not probable that their extraordinary movements are the result of any spontaneous efforts of the ani- mal, or are accompanied with any kind of perception or con- sciousness in these animals, which have never been found to present a single nerve in their bodies. The independent na- ture of the motion of those minute respiratory organs is observ- ed when we cut off the tentacula altogether ; and observe, that

expiration in the Infusoria and the Molluscce. The difference, then, between the density of the water expired and that of the surrounding water, proceeds from a difference of temperature." P- '297 — Raspail has defended this explanation of the phenomena at great length in the Mem. de la Soc. d'Hist. Nat. de

Paris, Tome iv. p. 131 — 142 Dr Mayer also denies the existence of cilia,

and concludes that the motion is produced by a peculiar substance named by him " vibratory matter," which adheres to the surfaces on which the pheno- menon shows itself. Brit, and Foreign Med. Rev. Vol. iii. p. 467. The expla- nation of Raspail, and the foolish hypothesis of Mayer, are completely disproved by the observations of Professor Grant on the Bcroe ; (Trans. Zool. Soc. i. p. 11.) and of Dr Sharpey on numerous animals — Edin. New Phil. Journ. July 1835.

OF POLYPES. 45

they still continue the rapid vibration of their cilia ; and though severed from the polypus, the tentacula continue to move for- ward through the water; the severed tentaculum of a flustra is Seen to swim through the water like a worm. The number of those organs varies much ; they are eight in Serialaria lendigera, and in Plumularia falcata, fourteen in Cellaria avicularia, twenty- two in Flustra carbasea. The effect of those motions of the ciha again is obviously to change the stratum of water constant- ly in contact with the most delicate fleshy parts of those zoo- phytes, with the highly organized soft irritable fleshy polypi. Thus they aerate the cellular texture of their body, at the same time that they bring the animalcules — their ordinary food — within the grasp of the tentacula."*

All polypes — ascidian and hydraform — subsist on animal mat- ter, feeding upon it either in a living state, or dissolved and sus- pended in the circumfluent medium. The Hydrse and smaller species seize on worm.s and animalcules brought accidentally with- in reach, or carried into the vortex formed by the play of the tentacular cilia :-|- the larger kinds (Helianthoida) sw^allow small crabs and shelled mollusca, rejecting the shells after having sucked out the soft contents. The food, in the Hydroida, is dissolved and necessarily made chylous in the stomach, and di- rectly absorbed from it ; but in the ascidian it is probable that the process of chylification is not completed until the food has passed into the intestine. In the higher animals the chyle is mixed with the blood and exposed to the influence of atmosphe- rical air before it is fitted for assimilation and growth ; and though bloodless, this air is no less necessary to the growth and exist- ence of polypes, which soon languish and die in vessels of un-

* Lect. C'omp. Anat. in the Lancet, 1834, Vol. ii. p. 959 " All the cilia ap- pear to commence and to cease their motions at the same moment. The con- stancy with which they continue would seem to exclude the possibility of their being the result of volition ; and they are, therefore, more probably determined by some unknown physical cause, dependent, however, on the life of the animal.' Roget, Bridgew. Treat, i. 173.

f " II seroit cependant possible de croire que ces animaux pourroient aussi bien se nourrir d'animalcules que les Hydres ; mais Cavolini dit positivemeut que, quoiqu'il ait souvent observe des polypes de gorgones, de millepores dans des eaux remplies d'animalcules, il ne les a jamais vus essayer a en saisir avec leur tentacules." Blainville, Man. d'Actinol. p. 97. Raspail nevertheless proves that they feed on them Mem. Soc. Hist- Nat. iv. p. 88.

4() STRUCTURE AND PHYSIOLOGY

renewed water. Hence the current within the tubes of some polypidonis which has been noticed : it is the movement of the nutrient thiid which has found its way from the ahmentary sac to tile surface of the body, where it is subjected to that agent which alone can fit it for the purposes of Hfe.

Amongst zoophytes there is no distinction of sexes, but every individual appears to be capable of producing reproductive buds or gemmules, or even eggs.* For the production of these, there is, in the opinion of some good observers, a peculiar organ or ovarium in all the ascidian tribes, and it is certain that their eggs are aU ways generated within the polype cell. There are appropriate productive organs also in the Helianthoida and Asteroida, in the former situated between the ligamentous dissepiments which ra- diate from the mouth to the base, between the stomach and the skin ; and in some of the latter attached to the membranous dissepiments in the abdominal cavity, while in others the gem- mules appear to sprout from every part of the abdominal cavity, and of the tube continuous with it. On the contrary, there is no local generative organ in any Hydroida — all are " full of re- productive life :" in the Hydra germs, similar in all respects to the substance of the body, sprout indiscriminately from every part of the surface ; in the Tubulariadae they pullulate from underneath the tentacula where they may frequently be observ- ed in clusters, and, in both of these families, the germs are naked or uncovered. But in the extensive family which em- braces the Sertularia and all its subgenera, the gemmules, at- tached in general to a central placenta, (which is but a continu-

* " These corpuscles differ from true ova and seeds, which are ripened by fe- cundation, inasmuch as the substance of which the new being is formed is r.ot, as ova and seeds are, enclosed in a special envelope, which is separated from them at the moment of the developement of the germ, and inasmuch as the formation of the new individual is owing to the entire substance of the repro- ductive corpuscle." — Ticdemann's Comp. Phy. 42 — " In the present slate of our knowledge, however," as Dr Allen Thomson well remarks, " the distinction between an ovum and a sporule (orgemmule) must be admitted to be somewhat arbitrary." — Cyclop, of Anat. and Phys. ii. 4-34.

In reference to the asexual character of Zoophytes it seems proper to mention in this note, that S\n\ and M. Delle Chiaje consider the Actiniae to be bisexous or herma])hroditical, (Blainv. Actinol. p. 79) ; and Raspail has hinted that a si- milar doublencss may be the property of the Alcyonella — Mem- sup. cit. p. 112. Nothing has yet been advanced to give these opinions a probable aspect.

OF POLYPES. 47

Htion of the fleshy central part of "the stem,) are enclosed in ve- sicles of the same texture as the polypidom itself, and neither proceed from, nor have any immediate connection with, the proper body of the polype, being evolutions from the pith or fleshy axis which connects the polypes together, and binds the various heads into one whole. — Such is a brief summary of the facts ascertained on this head, but it behoves me to mention that it is, to a certain extent, at variance with the opinions of Professor Grant. He maintains from his numerous observa- tions on a great variety of zoophytes, that the gemmules by which these animals propagate are highly organized portions of the gelatinous substance of the parent, formed " in almost every known zoophyte," and not merely in the Hydrazoa, as we have limited it, " by the common connecting substance of the ani- mal, and not by the polypi, which appear to be only the mouths or organs of digestion. In Plumularia?, Sertulariae, Campanu- lariae, horny Cellarite, Antennulariae, the ova are formed in ve- sicles which originate from the centre of the stem. In Flustra?, calcareous Celiarise, and some others, the ova are formed in the cells, but exterior to the bodies of the poh/pi, which disappear before the ova arrive at maturity. In the Lobidarise, Gorgonise, Spongiae, Clione, &c. the ova are formed and matured in the common Jleshy substance of the body before they advance to be discharged through the polypi, or the fecal orifices."*

I'he oemmules exhibit considerable variety in colour, — they are milk-white, yellow, red, pink or green, but sometimes the colour is not fully developed until near maturity. In all the as- cidian polypes they are globular or have a tendency to that form, and appear to preserve it until after their discharge from the body ; but in the Hydroida this is not the case, for although spherical in their earlier stages, " their shape alters on approach- ing maturity ; it elongates, becomes elliptical, next prismatic, and at length each corpusculum issues as a perfect animal from the orifice of the vesicle," and exhibits in figure and in motion much resemblance to the little leech-like Planaria?. (Fig. 6.-}-)

' Edin. Journ. of Science, No. 14.

t The figures represent the gemmules of Plumularia pluma. For the draw- ing I am indebted to my friend Dr Coldstream of Leith.

48 STRUCTURE AND PHYSIOLOGY

The gemmules are all clothed uiili vibratile Fig. 6.

cilia similar to those of the tentacula of the

parents. Sometime previous to their dis- / <^j M \ r^

charge from the polypidom 'they are observ- I / I f) \J J

ed to be in a constant rotatory motion, by which their birth seems to be facilitated ; and now at liberty in the water they move and swim about as if they were guided by volition and sense, whirling at the same time on their own axis.* This freedom to move whither they hst may continue for several hours, or even for two or three days, before a proper site for their permanent stay and future growth is found, when they begin to shoot up rapidly into those beautiful forms particular to each species, as the Supreme Being has ordered and deter- mined. The transformation of the ova, says Di' Grant, " from their moving, irritable, and free condition of animalcules, to that of fixed and almost inert zoophytes, exhibits a new metamor- phosis in the animal kingdom, not less remarkable than that of many reptiles from their first aquatic condition, or that of insects from their larva state." One purpose of this mobility in the ova is obvious ; — it is a means ordained for their diffusion, for the parents being fixed immoveably to one spot, the reproduc- tive germs would have dropt and sprung up at their roots, had thev not, bv some such mechanism as we have described, been carried to a distance, and spread over the bosom of the deep.

The evolution of the gemmules, subsequent to their fixation, has been minutely traced by Professor Grant and Sir J. G. Dalyell. When the bud falls from the crested head of Tubularia indivi- sa, slight prominences, enlarged at the tips, pullulate from the under surface, and the " nascent animal" elevating itself on these rudiments of the tentacula, as on so many feet, enjoys the faculty of locomotion. " Apparently selecting a site, it reverses

♦ In reference to those of Flustra carbasea — and tlie observation appears to be very generally applicable — Dr Grant says — " they are very irritable, and are frequently observed to contract the circular margin of their broad extremity, and to stop suddenly in their course when swimming ; they swim with a gentle glid ing motion, often appear stationary, revolving rapidly round their long axis, with their broad end uppermost, and they bound straight forward, or in circles, with- out any other apparent object, than to keep themselves atloat till they tlnd them- selves in a favourable situation for fixing and assuming the perfect state." — Edin. New Phil. Journ. iii. 117.

3

OF POLYPES, 49

itself to the natural position with the tentacula upwards, and is then rooted permanently by a prominence, which is the mcipi- ent stalk, originating from the under part of the head. Gra- dual elongation of the stalk, afterwards continues to raise the head, and the formation of the zoophyte is perfected."*— So the worm-like embryo of the vesiculiferous Hydroida, a few days after its exclusion from the vesicle, becomes stationary and con- tracts into a circular or spherical spot which always retains its original colour. It is transparent and soft, but in a short time some opaque fleshy spots are visible within it, and are separated by a thin homogeneous transparent substance, which is to form the future polypidoni. " As yet it is exceedingly minute, soft, and gelatinous ; but in the progress of its growth, the soft, thin, homogeneous substance of the exterior becomes more dense, embracing the first formed parts of the fleshy substance, indeed all parts, and the whole jelly, with its thin covering, and con- tinues to advance and to radiate. Then we observe a stem be- ginning to rise from the centre of these radii of roots, which are, in fact, the first formed parts that the little round gemmule shoots out. So that the gemmule is become, not a polypus but a root. It begins then to rise from the centre of the roots, and at length to divide ; so it will at length form on its branches a cell, at the bottom of which cell will gradually be developed a polypus." -f In the Flustra and other ascidian zoophytes the pro- cess is very similar, but in these, instead of the rootlets and little embryo stalk, a cell is the part first formed, in which a polype quickly and almost coetaneously developes itself; and this ori- ginal cell and polypus is as large, as perfect, as fit for every pur- pose to which it is destined as any of those which are in rapid succession evolved from its sides and apex, for age adds only to the number of individuals in the polypidom, and nothing to their perfection.

* Dalyell in Edin. New Phil. Joiirn. xvii. 412. f Grant, in the Lancet, 1834, Vol. i. p. 229.

Additional Notes.

1. BaspaiVs Description of the Structure of Polypes.

" I have pointed out tliat the polypus is nothing but the continuation of its

case, which becomes bony or cartilaginous in the lower part, in proportion as

the upper part is developed. Consequently its tube, or rather its involucrum,

D

50 STRUCTURE AND PHYSIOLOGY

instead of being a shapeless transudation from its body, is formed by successive additions of epidermoid membranes applied over each other in proportion as they are successively ossified. 1 have pointed out also that these polypi are merely microscopic fixed Cephalopodes, having, hke the large species of this genus, a bag which is contained within the tube, an excrementitial funnel, ovaries, an intestinal canal with similar curvatures, and a head with all its aecessories equally corresponding ; so that, if the Sepia, for example, instead of having the dorsal part of its large bag ossified, had undergone the same change over the whole external circumference of this organ, and if its base had been fastened by an adhesive substance to a rock, it would have been exactly a gigantic polypus." — New System of Org. Chem. p. 281-2. — Obs. The species on which Raspail made these curious observations are not mentioned in the work from which the extract is taken : they are applicable only to the ascidian polypes, and were indeed derived from the Alcyonella stagnorum, as we learn from his Memoir on this species in the fourth vol. of " Mem. Soc. Hist. Nat. de Paris."

2. Dr Grant's Account nf the Ova of the Fhistra. " Although the ova of Flustrae have been often observed, no one appears to have hitherto examined either their mode of formation within the cells, or their mode of developement after expulsion, so as to determine the real nature of these globular bodies, and the erroneous conjectures of naturalists respecting them have greatly perplexed the history of this genus. The ova of the F. carbasea make their first appearance as a small yellow point, a little below the aperture of the cell, and behind the body of the polypus ; they are unconnected with the poly- pus, and appear to be produced by the posterior wall of the cell, in the same man- ner as the axis, or common connecting substance of the polypi, produces them in other zoophytes. In this rudimentary state, they are found in the same cells with the healthy polypi, but, before they arrive at maturity, the polypi of such cells perish, and disappear, leaving the entire cavity for the developement of the ovum. There is never more than one ovum in a cell, and it occupies about a third of the cavity, when full grown and ready to escape. When first visible, it has a round or slightly oblong and regular form ; when mature, it is ovate with the small end next the aperture of the cell. The ova do not appear in all the cells at one time, nor is there any discernible order as to the particular cells which produce ova, or the part of the branch which contains them. Cells con- taining ova are found alike on every part of the branches, from the base to with- in two or three rows from the apex, occupied only by young polypi. Some- times we find half a dozen or a dozen of contiguous cells all containing ova, sometimes two or three only ; and often such cells occur singly, at short and irregular distances from each other. We find the ova in all stages of maturity on the same branch at the same time ; and we seldom observe a specimen of the F. carhasea, during the months of February, March, and April, which does not contain numerous ova. The ova have a lively yellow colour ; and when they occur abundantly on a specimen or a part of a branch, they cause it to ex- hibit the same lively hue, which is very dilferent from the dull spotted brown appearance which the branches present at other seasons. Cells are often ob- served on different parts of the branches, containing neither polypi nor ova ; but the fewness of these, and the great lumiber of cells still containing only polypi at the season of generation, render it probable that polypi are regenerated in the

3

OF POLYPES.

51

empty cells after the escape of tlie ova. In the empty cells from wLich the ova have escaped, we frequently observe a few remains of the former polypus, lying at the place where the body of the polypus bifurcated, and where the prin- cipal connection seems to exist between the polypus and the axis ; we likewise perceive numerous nionades and other animalcules busily employed in consum- ing the remains of the dead polypus. The ovum, even before arriving at ma- turity, exhibits very obvious signs of irritability, frequently contracting different parts of its surface, and shrinking backward in its cell ; the cilia on its surface are likewise observed in rapid motion within the cell, as in the ciliated ova of other zoophytes. The matuie ova are often found with their small end pro- jecting from the opening of the cells, and their final escape is aided by the in- cessant vibrations of the cilia covering their surface, by the ova contracting them- selves in their lateral direction, by the waves agitating the branches of the flus- tra, and by the same incomprehensible laws which regulate the formation and growth of the ova, and the whole economy of this zoophyte." — Edin. New. Phil. Journ. iii. II 6-7.

Egg of Alcyoxidium hirsuti'm.

52 FORMS OF THE POLYPIDOMS.

CHAPTER III.

The Classifications of Zoophytes.

The existence of a polypidom is not, as has been already mentioned, essential to a polype ; nor does it exercise, when present, that great influence over the organization of its archi- tects and tenants which might have been anticipated. Thus the animal of the madreporous Caryophylisea does not essential- ly differ from the naked Actinia; and the gelatinous Hydra is a true representative of the tenant of the sheathed Sertulariadse and Tubularia. No ascidian polype, however, is ever found detached, and without a polypidom ; and it is the same with all our native Astroida, but, perhaps, the clustered animal-flower (Actinia sociata, Ellis, Zoanthus, Cuv.) of the Caribbsean sea, might take its place in this tribe with greater propriety than in any other.

In reference to their composition, Polypidoms may be divid- ed into 1. the stony or calcareous, 2. the membrano-calcareous, and 3. the horny and flexible ; but the line which separates these divisions is often as uncertain and debateable as that which is traced between the sister kingdoms. All are composed of the same materials, viz. lime, and a gelatinous or membranaceous substance ; and their peculiar characters depend on the differ- ent proportions in which the materials are mixed. The calca- reous, which are hard and inflexible, and, when dry, assume a white colour, consist principally of carbonate of lime, with a small quantity of the phosphate of the same earth, and the gelati- nous matter which cements them into one coherent mass, is in sparing proportion : that proportion is so greatly increased in the polypidoms of the second section, that when the earthy in- gredients have been removed by the action of diluted acids, the structure retains its original form, and is, in fact, reduced to the

FORMS OF THE POLYPIDOMS. 53

condition of the polypidoms of the third section, which contain no Hme, or very little of it, but are formed of a condensed gela- tinous membrane, which resembles horn in every essential pro- perty.*

These diversities in their chemical composition appear to be of little value, either in a physiological or systematical point of" view, for in every order of polypiferous zoophytes, we find calca- reous and horny polypidoms. A curious species of Actinia se- cretes a horny basis, the first rudiment of a madrepore ;-\- but all other madrepores are calcareous : the axis of the Astroida is sometimes of lime, sometimes of horn, and sometimes of mem- brane : the polypidoms of the Hydroida are flexible and horny without perhaps any exception; but there is no hesitation in as- serting, that the ascidian tribes fabricate productions, some of which are referable to every class that the chemist could devise.

The reader who is not already familiar with the outward forms of our native polypidoms, will most easily obtain a correct idea of them, by examining the figures which illustrate this work. The very few and insignificant madrepores, or helianthoid poly- pidoms, which inhabit the British shores, form either short cy- linders or reversed cones, having the apex cupped and starred with lamellae, which radiate from the depressed centre to the cir- cumference. In the major part of the Astroida, or corticiferous polypidoms, there is a central calcareous or horny axis, which may be compared to the wood of a tree, and which is formed by the successive deposition of layer over layer : this is coat- ed or barked round with a living irritable flesh or jelly, thicken- ed with calcareous matter, which has usually crystallized in the form of spicula. The cells of the polypes are excavated in this soft bark, on the surface of which they open by an aperture, which is always cut into eight rays disposed in a starred fashion, and corresponding to the number of the polype's tentacula; and this aperture can be opened and shut at the pleasure of the inmates. In Alcyonium, although an asteroid, there is no solid axis, but

" See Additional Note.

•f It has been doubted whether this horny base is formed by the Actinia, but I quite agree with Dr Coldstream, that " it is secreted by its base, and that it is as much part of the animal, in fact its skeleton, as are the calcareous axes of Caryophyllaea, Fungia, &c. , between which and the true Actinia, it seems to form a well-marked link." — See the Edin. New Phil. Journ. ix. p. 238.

54 FORMS OF THE POLYPIDOMS.

there is an evident tendency to its formation ; the materials lie scattered in the form of spicula in the soft gelatinous centre; and in the Cydonium these spicula have become so numerous, that they impart considerable rigidity to the whole mass.

The polypidoms of the Hvdraform and Ascidian zoophytes are more diversified in their fiijures and more decidedlv arbores- cent. The latter are formed by an aggregation of distinct cells, united in general after the fashion of the quincunx and spread out into leaves or layers or compressed branches ; or the cells being placed upon each other in pairs, or even in a single line, they form neat confervoid tufts ; or lying immersed without any very traceable pattern, the masses resulting from their union are amorphous, or at least inconstant and irregular. The horny material of the Hvdra tribe isalwavs formed into tubular sheaths encasing the living flesh, jointed at intervals, sometimes of the same calibre throuohout, but more commonlv dilated at intervals into vases or cups, or cells, in which the proper body of the polype is placed. The manner in which the sheath or tube is divided and branched, is limited in diversity only by the num- ber of the species, which are among the most delicate and in- terestincr of all polypidoms, and pre-eminently imitative of vege- table forms. These forms are of course altogether independent of their aniniated tenants, — these " have been specifically ap- pointed by Him to do what they have done, and are still effec- tuating. They are meie instrumentalities at His conmiand. They know nothing of the results they cause, nor mean to per- form any of them, nor could of themselves co-operate with each other, nor produce any systematical arrangement, or regulated or orderly effects. It is their Master and Maker who organizes, governs, and guides them to those movements and operations which they perform, and from all others ; so that by His direct- ing will they are made to do what we see them effect, and that only because He restrains and averts them from all else."*

The formation of polypidoms has been the subject of con- siderable discussion. The opinion of Ellis, as we have already seen, was, that they are the result solely of a transudation, or excretion of the constituent matters from the body of the poly- pes, and this opinion has been maintained recently by Lamarck,

" Turner's Sac Hist, of the World, Vol. ii. p. 71.

FORMS OF THE POLYPIDOMS. 53

and some other naturalists. It rests on the assumption that the polypidom is extravascuhir and inorganic, so that after its first sohdification, it suffers no aUeration in form and quahty, beyond what is evidently effected by the operation of chemical and me- chanical causes : the changes resulting from its increase in size, are not from the activity and pulsion of any inherent principle, but from the super-imposition of additional layers, or from the additions of new cells, or from the prolongation of the tubes, which additions are all coetaneous with the growth and multi- plication of the polypes, and the results of new secretions. Lin- nceus, Pallas and Baster opposed Ellis, and believed in a vege- tative principle, inherent in the polypidom itself, so that its growth was in some measure independent of the living tenant ; and va- rious arguments have been brought forward by Bory de St Vin- cent,* which appear to him to demonstrate the truth of this doctrine. We may act, however, not unreasonably in withhold- ing our assent, for with such a feeble and errant point was the argument handled that few felt its force, and the discussion has continued even to this day in an unsettled state. It seems pro- bable in fact that neither theory will explain the growth of all polypidoms ; and as the peculiarities which distinguish these are considerable and would render a general description involved and obscure, I shall reserve the explanation of their mode of increase for a section in the preface to each separate order. Enough has in the meantime been said to show how unimportant the polypidom must be as a primarij character in a natural classifi- cation of zoophytes, and yet, until very recently, no other basis was looked for or deemed available, and hence the artiiicialness of the proposed " Systems" which, as a matter of history, we now venture to review.

The Classifications of Zoophytes. The main object of Ellis being to prove the animality of zoo- phytes, he deemed a new classification of them unnecessary, and, as it was sufficient for his purpose, he followed very closely that which had been proposed by Ray in his Synopsisof British Plants, f In successive chapters he treats of the vesiculated corallines { Sertulariadse), the tubular corallines (Tubularise), of the cel-

• Encyclop. Method, art. Zoophyte.

t Syii. Meth. Stirpium Brit. Edit. 3. Load. M'lA.

•)6 CLASSIFICATIONS OF ZOOPHYTES.

liferous (Cellariadae), and of the articulated corallines (Coral- lina), of Keratophyta, of the Eschara, of the English corals, of sponges, .of the Alcyonium, and of tubular corals, under which head he describes several of the more common tubicolous worms, which are found on our coast, and which have no rela- tionship whatever to the other subjects of his treatise. Look- ing back on this arrangement from our present vantage ground, it appears disorderly and very defective, but when we reflect how fmperfect the knowledge of species was at that period, and how crude the notions were on the nature and use of systems, we may find much to commend in it. Some of the chapters indeed contain a mixture of very dissimilar things, but others may be justly considered as so many natural genera or families, which subsequent naturalists had merely to subdivide and name.

Linnffius — in every sense the first of systematists — published the tenth edition of his Systema Naturae in 1758. In it the avertebrate animals are arranged in two classes, Insecta and Vermes, — and of the latter zoophytes, with the exception of Ac- tinia which is placed amongst the mollusca, form the last two orders which he named Lithophyta and Zoophyta. That we may appreciate the nature and value of the changes proposed subsequently to his time, it will be necessary to give the defini- tions of his orders and genera.

I. " LITHOPHYTA Mollusca coraposita, basin solidam sedifi-

cantia. TuBiPORA CoraUimn tubis cylindricis. MiLT.EPORA CoraUium tubis obconicis teretibus. Madrepora CoraUium tubis stellatis."

II. " ZOOPHYTA PlantaB vegetantes floribus aniraatis.

Isis Stirps radicata, lapidea, nuda, geniculis corneis. GoRGONiA Stirps radicata, cornea, crustata, contlnua. Alcyonium Stirps stuposa, corticata, contlnua. TuBULARiA Stirps fistulosa, tunicata, subgeniculata. Eschara Stirps papyracea, nuda, porosa. CoRALLiNA Stirps fibrosa, crustata, artlculata : artlculls multi-

florls. Sertularia /.V^tVjo* fibrosa, nuda, artlculata: artlculls unifloris. Hydra Stirps subradlcata, gelatlnosa, apice florifera. Pennatula Stirpjs libera, pennata, basl ore instructa.

CLASSIFICATIONS OF ZOOPHYTES. 57

Tjenia Stirps libera, moniliformis, articiilata. VoLVox Stir-ps libera, globosa, sobole nidulante." *

The precision of the definitions in this arrangement, and the manner in which they are contrasted, is highly characteristic of its author, but into many of the genera species are introduced, which are not conformable to the definitions ; and some of these, Pennatula and Hydra, for example, are grossly erroneous. The theoretical character of the second order, and of some of its ge- nera, might also be objected to in a matter-of-fact work ; but it is an easy task for the student of the present sera to point out defects in the method of the master who had to plan the way, and who succeeded in making it level and easy to his followers.

Pallas, in 1766, embraced the Lithophyta and Zoophyta in one order, for which he adopted the latter denomination, for he very properly believed that the Linnsean distinctions served on- ly to " divide the things that are in nature join'd." He sepa- rated some spurious species of Hydra and formed them into the genus BrachioriKS, which, though a good genus, is a duubtful member of the order of zoophytes. His genus Antipathes, se- vered from Gorgonia, is well defined ; and m\h equal propriety he restored the celliferous corallines of Ellis, which Linnaeus had mixed with the Sertularia, to a separate generic rank — Cel- lularia. The claims of Taenia, Volvox, and Corallina to a place amongst zoophytes were disallowed, although he has described the species in an appendix, for he knew that Taenia properly belonged to the intestinal worms, and Volvox to the infusorial animalcules ; and he believed that Corallina was altogether of a vegetable nature.

In the twelfth edition of the " Systema," published in 1767, Linnaeus made no material improvements on his first system, but the errors relative to the Hydra and Pennatula are corrected, and the definitions in general are abridged and rendered less theoretical. To the Lithophyta he added the genus Cellepora — " corallium cellulis cavis ;" — and he followed Ellis and Pallas in now introducing the Sponges into his second order. In this we also find, for the first time, the genus Vorticella, which is near- ly synonymous with the Brachionus of Pallas ; the Flustra, which

* Syst. Nat. p. 646. Halte Magdeburg. 1760,

58 CLASSIFICATIONS OF ZOOPHYTES.

is the same as Eschara of his preceding edition ; the Furia, which is an apocryphal animal ; and the Chaos, which is an in- fusory animalcule. Were we to analyze the genera we should find, in almost every one of them, species which properly belong- to a different class of animals, or whose characters are at vari- ance with those assig-ned to the genus : but many of these mis- placements were the almost necessary consequences of the then state of knowledge relative to the beings in question.

Solander, in arranging the materials of Ellis, followed the system of Pallas, but he introduced and placed the Actiniae at the head of the order ; he entirely rejected all the intestinal worms and infusory animalcules; and he amended the defini- tions of the genera by carefully avoiding all theoretical phra- seology. He used the term " Zoophyta" exactly in the same sense, and with the same latitude, that it is used in the present work.*

The method of Miiller cannot be considered as any improve- ment on those of his predecessors, but there is an attempt after novelty in it. He places the Actinia and the Hydra among the MoUusca, an order full of heterogeneous things, embracing the cuttle-fish, snails and star-fish ; and in the same order we find the beautiful Lucernaria, one of the discoveries of this indus- trious and excellent naturalist. The proper zoophytes he de- nominates Cellularia, which are defined to be compound ani- mals, enclosed in cells, and propagating by means of buds. The genera are classed and defined as follows :

* Calcarea.

Articulata, tenera, . . Corallina.

Articulata, lapirlea, . . Isis.

Tubulosa, aggregata vel solitaria, . Tubipoka.

Foraminulosa, . . • Ckllepora.

Lamelloso-stellata, . . . Madrepora.

Pertusa poris, . . . Millepora.

** Subcornea. Tubulosa, tenlaculis simplicibus, . Fistula bia.

Tubulosa, lentaculis cristatis, . Tubularia.

• The Natural History of .many rurious and uncommon Zoophytes, by the late John Ellis, systematically arranged and desfribed by the late Daniel Soland- er. I. find. 17H6. -tto.

CLASSIFICATIONS OF ZOOPHYTES. 59

Ramosa, niida, ^ewtoCM^t* manifestis, . Sertularia.

Hamosu, incrustata, tent, inconspicuis, . Gorgonia.

*** Fungosa.

()ssiculum polypiferiim, . . Pennatula.

Suberosa, polypis stellatis, . . Alcyonium.

Stuposa, oscnlis hiantibus, . . Spongia.

Osculis atomiferis, . . . Clavaria.*

The last genus is a sort of mushroom \\hich Muller was led to arrange among zoophytes from having witnessed the appa- rent spontaneous movements of its sporules ; but no one has fol- lowed him in this, ahhough, it may be remarked, that some re- cent authors have no better reasons for their proposal to re- move a large proportion of the aquatic algse to the animal king- dom.

Blumenbach adopted the Linnsean class Vermes, and he also retained the Actiniae in the order MoUusca, but the proper zoo- phytes were differently arranged, and the alteration was unques- tionably for the worse. The " polypes and other zoophytes inhabitinof coral branches and similar structures" formed the or- der Coralliu ; and his Zoophijta included only the " naked plant-like animals without any habitations ; also the animalculse of infusions!" The genera were the same, or nearly the same, as the Linnoean, and followed one another apparently as their names had risen in random series to his memory.^

About the beginning of the present century Cuvier first of all pointed out the advantages of having our systematical arrange- ments in harmony with anatomical structure, — of making the one an index to the other, — of classifying animals not according to one or two external characters which might really have little or no influence upon their anatomy and habits, but according to their agreement in those great systems by which the life, growth, and propagation of creatures are upheld and carried on. When, however, he began to arrange the animal kingdom according- ly, the knowledge of the organization of Zoophytes was too im- perfect to permit him to follow out his principles in this depart-

* Zoologise Danicse Prodromus, p. xxxi. Havn. 1776.

t Elements of Natural History, p. 269 and 274. Loud. 1825.

60 CLASSIFICATIONS OF ZOOPHYTES.

ment, and even his latest systematical attempt exhibits many de- relictions of them. Having, at the suggestion of Pallas, establish- ed a section of avertebrated animals for the reception of such as exhibited in the disposition of their organs a radiated appearance, to the whole of which he applied the term Zoophytes, he sub- divided it into five classes, of which the last but one embraced the subjects of the present treatise. They were named Polypes because, from the tentacula encircling their mouth, they some- what resembled the cuttle-fish called Polypus by the ancients ; and they were defined to be little gelatinous animals the mouth of which, encircled with the tentacula, lead into a stomach some- times simple and sometimes furnished with intestines in the form of vessels. It is in this class that we find those innumerable com- pound animals, with a fixed and solid stem, which were so long re- garded as marine plants. The following is a synopsis of Cuvier's method, as it appears in the last edition of the " Regne Animal."*

Les Polypes.

Ord. I. P. CHARNUS.

Les Actinies. (Actinia, Lin.)

Actinia.

Zoanthus. Ctiv. (nov. gen.) Les Lucernaires.

Lucernaria.

Orel. II. P. GELATINEUX.

Hydra.

Corine.

Cristatella. Cuv. (nov. gen.)

Vorticella.

Pedicellaria.

Ord. III. P. A POLYPIERS.

Fam. i. Les Polypes a tuyaux. Tul)ipora. Tubularia. Sertularia.

Fam. ii. Polypes a cellules. Cellularia.

* Paris, 18.30, Vol. iii. p. 289 el seq.

CLASSIFICATIONS OF ZOOPHYTES. 61

Flustra. Cellepora. Tubiilipora. Corallina.

Fam. iii. Les Polypes corticaux. Tribe 1. Des Ceratophytes.

Antipatbes. ■

Govgonia. Tribe 2. Les Lithophytes.

Isis.

JNIadrepora.

Millepora. Tribe 3. Polypes Nageurs.

Pennatula. Subgenera — Pennatula, Cuv. Virgiilaria, Lam. Scirpearia, Cuv. Pavonaria, Cuiu Renilla, Lam. Veretillum, Cuv. Ombellularia, Cuv. Tribe 4. Alcyons.

Alcyonium.

Spong-ia.

In the definitions there is throughout a certain degree of vaofueness, or at least the absence of that finicalness, which is so pleasing to the practical systematist ; and in the value of the characters chosen to separate the orders and families there is great inequality. Hydra and Corine, for example, are more nearly allied to Tubularia and Sertularia, than the latter are to the Ceratophytes, yet these are placed in one and the same, and the Hydra in a separate order. Had the Ceratophytes been elevated to the rank of an order, and the Ma- drepora been removed to the Polypes chamus, the system would have been improved, and no very obvious alliances broken. In the subordinate parts of the system there are many misplace- ments of the subgenera, as the genera of his contemporaries were named, of which we may instance the Campanularia which is placed under Tubularia of Linnaeus, to which, however, it has certainly much less affinity than to the Sertularia, where it had always hitherto been assigned.

In 1810, Lamouroux of Caen presented to the Academy of Sciences of Paris a new classification of the flexible polypidoms; and it would appear that Lamarck was engaged at the same time

Cy2 CLASSIFICATIONS OF ZOOPHYTES.

in similar labours; but, proceeding on different principles, they arrived at very different results. The anatomy of the workers or polypes was, according to Lamouroux, so imperfectly ascer- tained, and from their situation as well as from their minute- ness, so little within attainment, that it seemed hopeless to pro- cure materials for a classification from that source, and he con- fined his attention solely to the polypidoms, on whose composi- tion he founded his primary divisions. Lamarck, although he also confined his examination to the polypidoms, took higher ground : he maintained that as these were secreted by the poly- pes and formed on and by them, a sameness in the structure of the one necessarily implied a sameness in the structure of the other; that in fact we might as safely infer a sameness of struc- ture or dissimilarity from the various configurations of the poly- pe-cells and coral, as we could from an actual inspection of the animated tenants themselves. The experience of a few years has shown either that Lamarck's examination of the coral was hasty, or that his principle was erroneous, for his arrangement is far from being in harmony with a physiological one, and, although greatly superior to Lamouroux's, yet is not the less ar- tificial ; there being even in some of his genera, species whose polypes are widely at variance with each other. I do not mean to trace the systems of either of these authors through their va- rious changes, from their first promulgation to their perfection ;* an outline of them in their latest state is sufficient for our purpose.

System of LAMOURoux.f (182L)

Division I. POLYPIDOMS FLEXIBLE, OR NOT ENTIRELY STONY.

Section 1. PoLYPiERS CELLULIFERES. — Polypes in non-irritable cellules. Ord. I. Celleporees. — Tubulipore. Cellepore. Ord. II. Flustrees. — Berenice. Pheruse. Elzerine. Flustre. Electre.

* Blainville has given a history of all the proposed classificatiors in chrono- logical series in his Manuel d'Actinologie, which the reader may consult with advantage.

t The primary sections of this systematist may have been borrowed from J. E. Roques de Maumont Sec Blainr. Man. d'Actinol. p. 2-3.

CLASSIFICATIONS OF ZOOPHYTES. 6;i

Ord. III. Cellariees — Cellarie. Caberee. Canda. Acamarchis

Crisie. Menipcc. Loricaire. Eucratee. Alocto. Lafaee.

Hippothoe. Aetee. Ord. IV. Sertulariees. — Pasythee. Amathie. Nemertesie. Aglao-

phenie. Dynamene. Sertulaire. Idie. Entalophore. Clytie.

Laomcdee. Thoee. Salacie. Cymodocee. Aniphitoite. Ord. V. Tubulariees. — Tibiane. Nais. Tubulaire. Cornulaire. Te-

lesto. Liagore. Neoraeris.

Section II. PoLYPiERS CAtciFERES — A calcareous substance mixed with the animal matter or covering it, apparent in all its states. Ord. VI. Acetabulariees — Acetabulaire. Polyphyse. Ord. VII. Corallinees. — Galaxaure. Nesee. Janie. Coralline. Cy- raopolie. Amphiroe. Haliraede. Udotee.

Section III. PoLYPiERS CoRTiciFERES. — Composed of two substances, an exte- rior and enveloping, named the bark or crust ; the other, called the axis, placed in the centre and sustaining the tirst. Ord. VIII. Spongiees — Ephydatie. Eponge.

Ord. IX. Gorgoniees .4nadyomene. Antipathe. Gorgone.

Plexaure. Eunicee. Municee- Primnoe. Corail. Ord. X. Isidees. — Melitee. Mopsee. Isis.

Division II. POLYFIDOMS ENTIPtELY STONY AND INFLEXIBLE.

Section I. PoLVPiERs FORAMiNES. — Cells small, perforated, almost tubular, without internal plates. Ord. XI. Escharees. — Adeone. Eschare. Retepore. Discopore.

Diastopore. Obalie. Celleporaire. Ord. XII. IVIilleporees. — Ovulite. Reteporite. Lunulite. Orbulite. Ocellaire. IVIelobesie. Eudee. Alveolite. Distichopore. Hornere. Krusensterne. Tilesie. Theonee. Chrysaore. Mil- lepore. Terebellaire. Spiropore. Idmouee.

Section II. PoLYPiERs LAMELLiFERES. — Stony, the cells in the form of lamel- lated stars, or waved furrows garnished with lamellae.

64 CLASSIFICATIONS OF ZOOPHYTES.

Ord. XIII. Caryophyllaires.— Caryophyllie. Turbinolopse. Tur- binolie. Cyclolite. Fongie.

Ord. XIV. Meandriiiees —Pavone. Apsendesie. Agarice. Mean- di-ine. Monticulaire.

Ord. XV. Astrees.— Echinopore. Explanaire. Astree.

Ord! XVI. Madreporees— Porite. Seriatopore. Pocillopore. Ma- drepore. Ociiline. Styline. Sarcinule.

Section III. PoLYPiERs TUBULES.— Stony, formed of distinct and parallel tubes. Ord. XVII. Tubiporees.— Catenipore. Favosite. Eunomie. Tubi-

pore.

Division HI-

POLYPIDOMS CARNOSE, MORE OR LESS IRRITABLE AND WITHOUT A CENTRAL AXIS.

Ord. XVni. Alcyonees.— Alcyon. Lobulaire. Ammothee. Xenia.

Anthelie. Alcyonidee. Alcyonelle. Hallirhoe. Ord. XIX. Polyclinees — Distome. SigiUine. Synoique. Aplide.

Polycline. Diderane. Eucelie. Botrylle. Ord. XX. Actinaires.-Chenendopore. Hypalime. Lymnoree.

Pelagie. Montlivaltie. Isaure. leree.

Remark on this system seems almost unnecessary. The student will deem it too complex with all its sections and sub- sections ; and the experienced naturalist will at once eschew it as only tending to embroil, and confuse and nulhfy all the know- ledae which has been acquired on the structure and physiology of the remarkable creatures which are here so elaborately mis- arranged. Animals which the admirable anatomical researches of Savignv had proved, by the consent of all, to belong to a dif- ferent category, are here forcibly degraded to their Linnaean rank, and stand in juxtaposition with true zoophytes on the one hand, and doubtful ones on the .other ; and, perhaps to make room for these pretenders, some rightful claimants, as Hydra and Pennatula, are altogether excluded : some genera so nearly aUied that their distinction may be questioned, for ex- ample, Flustra and Eschara, stand in different divisions at wide distances ; while others, which have not one character of im- portance to connect, and every thing to dissever them, are placed

CLASSIFICATIONS OF ZOOPHYTES. 65

almost in juxtaposition, as the Sponges and the Gorgoniae. The merits of Lamouroux have always appeared to me to have been much overrated : it is a very easy matter, by arbitrarily fixing on this or that character, to set in order any given number of objects in any pattern we may choose, and Lamouroux had no higher notion of the character of a systematist than this, and acted accordingly. It is very true that he named and distinguish- ed many genera, but who, on critically examining these genera, will deny that he proceeded without caution and without judg- ment,—determined apparently to make as many as could be made that his successors might be spared the unprofitable task of coining and inventing names ! *

System of Lamarck. (1816.)

Class POLYPI. Order I. P. ciliati. Polypes without tentacula, but having near the mouth, or at its ori- fice, vibratile cilise or ciliated and rotatory organs which agitate

or whirl the water.

I. ^gc«Jo».— ViBRATiLES.— Rattulus, Tiichocerca, Vaginicola.

II. Section. Rotiferes. — FoUiculina, Brachionus, Furcularia,

Urceolaria, Vorticella, Tubicolaria.

Order II. P. denudati. Polypes with tentacula, without an envelope or polypidom, and fixed either permanently or spontaneously.

Hydra Coryne — Pedicellaria — Zoantha.

Order III. P. vaginati. Polypes with tentacula, invariably fixed in an inorganic polypidom which envelopes them ; and forming, in general, compound animals.

* Polypidoms of homogeneous composition. I. Section. Polypiers fluviatiles.— Difflugia, Cristatella, Spongilla, Alcyonella.

* BlainviUe in criticising Lamouroux's latest work, says—" Nous nous bor- nerons a dire que Lamouroux a encore considerablement augraente le nombre des genres, surtout parniiles polypiers pierreux, pour y placer un grand nombre de corps organises fossiles, trouves dans le calcaire a polypiers de Caen, et que malheureusement la plupart de ces genres sent mal caracterises, ce dent je me suis assure directement sur les objets memes qui out servi a ses observations. Man. d'Actinol. p. 54.

06 CLASSIFICATIOXS OF ZOOPHYTES.

II. Section. Polypiers vaginiformes. * Polypidoms naked, not

varnished nor encrusted on the exterior. (J) Cells terminal

Plumatella, Tubularia, Cornularia, Campanularia. (2)

Cells lateral — Sertularia, Antennularia, Plumularia, Seria-

laria. ** Polypidoms varnished or slightly crusted on the

exterior. Liriozoa, Cellaria, Anguinaria, Dichotoraaria, Tibiana, Acetabulum, Polyphysa.

III. Section. PoLYPiERS A RESEAU. — Flustra, Tubulipora, Dis-

copora, Cellepora, Eschara, Adeona, Retepora, Alveolites, Ocellaria, Dactylopora.

IV. Section. Polypiers foramines. — Ovuhtes, Lunulites, Or-

bulites, Distichopora, Millepora, Favosites, Catenipora, Tu- bipora.

V. Section. Polypiers lamelliferes. — * Stars terminal — Sty-

lina, Sarcinula, Caryophyllia, Turbinolia, Cyclolites, Fungia. ** Stars lateral or spread over the surface — Pavonia, Aga- ricia, Meandrina, Monticularia, Echinopora, Explanaria, Astrea, Porites, Pocillopora, Madrepora, Seriatopora, Ocu-

lina.

VI. Section. Polypiers corticiferes — Corallium, Melitaea,

Isis, Antipathes, Gorgonia, Corallina.

VII. Section. Polypiers empates Penicillus, Flabellaria,

Spongia, Tethia, Geodia, Alcyonium.

Order IV. P. tubiferi. Polypes united on a common fleshy living body, either simple or lob- ed or branched, and attached by its base : no external polypidom ; no solid internal axis ; the surface loaded with numerous tubiform little cylinders, rarely entirely retractile. Mouth terminal ; ten- tacula 8, pectinated ; no anus ; 8 longitudinal semi-partitions un- derneath the stomach ; 8 intestines of two kinds ; 6 groups of gem- mfB resembling as many ovaries.

Anthelia, Xenia, Ammothea, Lobularia.

Order V. P. natantes. Polypes united on a common fi-ee elongated fleshy and organic body, enveloping a cartilaginous almost bony and sometimes stony inor- ganic axis. Tentacula set in a radiating manner round the mouth of each polype. Veretillum, Funiculina, Pennatula, Renilla, Virgularia, Encrinus,

Umbellularia.

CLASSIFICATIONS OF ZOOPHYTES. 67

In the outline this system is not very materially different from that of Cuvier, the deviations being sometimes for the better and sometimes for the worse. If the Polypi ciliati are to be numbered amongst proper zoophytes it is for the better to have them placed in a separate order ; but Zoantha is badly associat- ed with the Hydra, Coryne and the spurious Pedicellaria. The Polypi vayinati, considered as an order, is a most heterogene- ous collection ; and the manner in which it is subdivided into sections, although in general excellent and worthy of commen- dation, is yet far from unexceptionable ; and these exceptions are very obvious in the first, sixth and seventh sections, in which apolvpous, or it may be vegetable productions, are mingled with real zoophytes. The characters which divide the Polypi tuhiferi from the natantes are not of sufficient importance to be consider- ed ordinal, (it would have been preferable to have made them fa- milies in one order) ; and the location of the Encrinus in the latter is the result of a most unlucky conjecture.* As a systematist, how- ever, Lamarck has few equals, and probably, with the exception of Linnaeus, not a superior : there is no vagueness nor ambiguity about him, — all is clear, well arranged and ordered, and his characters, which are usually well chosen, are defined in expres- sive words and in a felicitous manner. These advantages have given his System great currency, and though the favour shewn to it has somewhat abated, it still holds its place, and is in frequent use, with those who are engaged in arranging local catalogues and museums.

Dr Fleming is the only British naturalist who has attempted

* According to Lamarck Nature could not have done othei-wise than she has done, and we are repeatedly assured that his System is a naked exposition of her necessitated steps in calling organized beings into existence ! After announcing with an almost ludicrous degree of confidence and complacency, that this ficti- tious Power can only complicate animal organizations in successive gradation, he adds, — " La connaissance de cette v^rite me suffit ; je reconnais le veritable rang des polypes, comme celui des infusoires ; j'aper9ois les rapports quiles lient les uns aux autres, ainsi que ceux qui lient les families entr'elles ; enfin, je con9ois les limites que la nature n'a pu franchir dans la composition de I'organization de ces animaux, d'apres celles que je decouvre dans ceux des classes superieures. Je puis done dire positivement, a I'egard des polypes, comme a celui de bien d'autres, ce que la nature n'a pas pu faire." Anim. s. Vert. ii. 8 — What a hu- miliating commentary and lesson have the discoveries of a few short years af- forded on this passage !

68 CLASSIFICATIONS OF ZOOPHYTES.

an original classification of Zoophytes, and although no one, from his previous studies and important discoveries relative to their structure and functions, ever came better prepared for the task, yet the system he framed is assuredly not superior to those of his predecessors. The Actinise and Lucernaria were collocated with the Radiata acalejjha or sea-jellies, and the Zoophyta divid- ed into four orders as follow:*

I. Carnosa. Polypi connected with a fleshy substance. Keeping this definition in view, who would have expected to find Sponges and Corallines and Madrepores under this order ? and yet they are there in defiance of the definition. The following is a sy- nopsis of this order —

I. Free ; marine ; moving by the contraction or expansion of the Jleshy part ; form symmet7'ical ; axis of the body supported by a

bone contained in a sac.

Pennatula. Virgularia.

II. Fixed or stationary,

A. Polypiferous matter covering a solid axis.

a. Axis with stellular discs LAMELLiFERiE.

b- Stellular discs terminal. Sarcinula. Lithostrotion. Caryophyllea. Turbinolia. Cyclotites. b b. Stellular discs aggregated. Explanaria. Astrea. Porites. Pocillopora. a a. Axis destitute of cellular discs.

b. Axis corneous and flexible ; polypiferous basis cre- taceous ; the axis with spines, c. Polypi developed. — GorgoniadjE. Gorgonia. Primnoa. c c. Polypi not developed. — Corallinad^. Jania.

" History of British Animals, Edin. 1828. 8vo.

CLASSIFICATIONS OF ZOOPHYTES. 69

Corallina. Halimeda. b b. Axis stony. Isis. B. Polypiferous basis destitute of a continuous solid axis. a. Polypi developed.

b. Polypi with 8 tentacula ; the base fibrous. Lobularia. Cydoniura. Cliona. b b. Polypi with tentacula exceeding- 8 in number ; basis nearly uniform. Alcyonium. Cristatella. a a. Polypi not developed. — Sposgiad^. Tethya, Halichondria. Spongia. Grantia.

II. Cellulifera. Polypi lodged in calcareous cells imperforate at the

BASE.

A. Substance rigid, stony.

I. Cells in the form of minute pores, imbedded — Mille-

PORADiE.

Millepora.

II. Cells tubular, and produced beyond the surface. — Tu-

BIPORAD^.

Tubipora. Favosites. Tubulipora. Discopora. Filipora. Terebellmna. III. Cells uti'icular, adjacent, or superimposed. — Escha-

RADJE.

Eschara. Retepora. Cellepora. Berenicea.

70 CLASSIFICATIONS OF ZOOPHYTES.

Hippothoa. Alecto. A A. Substance flexible. — Flustrad^. Farcimia. Flustra.

III. Thecata. Polypi surrounded by a membranaceous tube, covering

THE subdivisions OF THEIR COMPOUND BODY.

A. Sheath slightly calcareous ; cells single, or in rows.

I. Sheath slightly calcareous, cells enlarged, in rows, united or single. — Cellariad^. a. Cells united.

b. Cells with the orifices opening on the upper surface. Cellularia. Tricellaria. Crisia. b b. Cells in pairs, attached by the back, the orifices with opposite aspects. Notamia. a a. Cells single.

Eucratia. Anguinaria. A A. Sheath membranaceous, cells enlarged externally and lateral,

SERTULARIADiE.

I. Base of the cells broad, coalescing with the stem. a. Cells on opposite sides of the stem. Sertularia. Dynamena. Thuiaria. a a. Cells unilateral.

Antennularia. Plumularia. Serialaria. II. Base of the cells narrow, or pedunculated. Campanulai'ia. Valkeria. Cymodocia. AAA. Sheath membranaceous ; the cells are the simple extremities of the branches. — Tubulariad^e. Tubularia. Plumatella.

4

CLASSIFICATIONS OF ZOOPHYTES. 71

IV. NUDA.

Polypi naked, the mouth with marginal tentacula. Coryna. Hydra.

Latreille's method may next be noticed. He, following La- marck, divides the animal kingdom into three primary sections, the last of which is denominated Acephala, which, with various other classes, includes all the Zoophyta. The Actinia and Lu- cernaria constitute a distinct class — Helianthoida — which is placed between the sea-stars (Echinodermata), and sea-jellies, (Acalepha), being superior to the latter and to zoophytes by their organization, in which Spix had detected a nervous system. The Polypes follow the sea-jelhes, and are subdivided thus :

Order I. Brachiostoma. Month encircled with tentacula, often relractile. Family I. Calamides. Pennatula, Virgularia, &c.

• II. Alcvonea. Lobularia, Alcyonium, S:c.

III. Alveolaria. This family is portioned into tribes.

1. LamelUfera — the P. lamelliferes of Lamarck.

2. Foraminosa — the P. foramines of Lamarck.

3. Corticifera — the P. corticiferes of Lamarck, with

the genera Penicillus and Flabellaria.

4. Reticularia — the P. a resean of Lamarck.

5. Vaginiformia — the P. vaginiformes of Lamarck.

6. Spongites — the sea and fluviatile sponges. IV. Limnopolypi. 1. Tentacula i-etractile ; a sheath —

Plumatella, Cristatella, Difflugia. 2. Tenta- cula non-retractile ; no sheath — Pedicellaria, Coryne, Hydra.

Order II. Trichostoma. No tentacula at the mouth, which are replaced by rotatory organs or

cilice. Family I. Cancriformia — Brachionus, Follicularia, Tul)icolaria.

II. Campanulata — Vorticella, Urceolaria, Furcnlaria.

HI. Caudata — Vaginicola, Tricocercus, Ratulus.

Not having access to the original works, I pass over in silence the methods of Oken, Schweigger, and Van der Hoven, the

72 CLASSIFICATIONS OF ZOOPHYTES.

more willingly that they are but modifications, to no material extent, of one or other of those which preceded them, are in no respect preferable, and evolve no new principle, for surely the assumption on Oken's part that the orders, families, and ge- nera in this class, as in the animal kingdom generally, are re- gulated by a law which throws them into quaternary sections — the number 4 exercising throughout a paramount influence — scarcely deserves this praise. It is different with the attempt of Rapp, Professor of Anatomy at Tubingen, who in 1829 published a small work in German on the natural history of the Actiniae. He proposed to divide the zoophytes, understanding the term in the same restricted sense that I do, into two great or- ders, the ExoARiA and Endoaria, — the former producing their ova or reproductive gemmules from the exterior, while in the latter " the ova are produced in the interior of the body, and are either conveyed outwards by means of oviducts which open by separate orifices, or they are discharged by the mouth." The distinction here first pointed out is a very important one, but in common with all single characters is of itself insufficient, and if rigorously adhered to leads to artificial and unnatural com- binations. The Exoaria for example has all its members well and distinctly affined, embracing only three families, 1. the Hydra ; *2. Curynea, consisting of the genera Sertularia, Tubu- laria and Coryne ; and 3. Millepora^ limiting probably this de- nomination to M. triivcata. The Endoaria embraces a wider range — the Alcyonea equivalent to the Polypes tubiferes of Lamarck ; the Tupipora ; the Corallia including the genera Corallium, Gorgonia, Isis and Antipathes ; the Pennatulce ; Zoanthes ; and Madrejjores with the subdivisions which have been introduced by Lamarck. * So far the order labours under little error, or is perhaps unexceptionable, but its definition would entitle us to place in it also the Escharidae, the Celle- pores, and Lymnopolypi, which are all very alien to the families which Rapp seems to have had too exclusively under his view. The only other classification I shall notice is Blainville's, — the most elaborate of any ; and this author, as it appears to me, is the first who allowed the anatomy of the Polypes, abstractedly

* See Edin. Joiirii. of Geogr. and Nat. Science, ii. p. 406, and Blainv. Man.

d'Aetinol. p. 59.

3

CLASSIFICATIONS OF ZOOPHYTES. 73

considered, to have its due influence on our systems. Notwith- standing, however, Bhiinville's unquestionable merits, his very defective acquaintance with species will ever prevent him be- coming a first-rate systematist : he may sketch the outline, the details he cannot supply, and his attempt has exposed him to numerous errors : he is too fond of generalizations where his facts are few and specifical ; he wants the necessary neatness and brevity of definition, and he evinces everywhere such a to- tal disregard to the old nomenclature that his system is not like- ly to become popular, or to be generally adopted. Many of his alterations are excellent, and must meet the approval of all, for surely no one will henceforth reinstate the apolypous sponges and vegetating corallines, which he has so properly separated, to a rank amongst proper polypes ; and his removal of the Ma- drepores from the compound hydracolous polypidoms to a level with the Actiniae seems to be equally judicious, and beyond fu- ture cavil.

System of H. M. D. De Blainville. (1834.)

Class— ZOANTHA.

Body regular, resembling- a flower, more or less elongated, free or fixed, very contractile, furnished with an intestinal canal without distinct parietes, and with a single large terminal aperture encircled with multiform tentacula, always hollow, and in communication with the musculo-cavernous parenchyma of the skin.

The class is divided into three families :

The Soft — Actiniadse. Lucernaria, Actinia, &c. The Coriaceous — Zoanthus.

The Calcareous— divided into 1. the MadrephylUcea, in which are the genera Turbinolia and Caryophyllaea : and 2. the Ma- drepores.

Class— POLYPIARIA.

Animals like the Hydra, viz. in general slender, furnished with a single series of filiform and not numerous tentacula, naked or con- tained in multiform cells (but never lamelliferous), clustered so as to form a polypidom very variable in shape and structure. Sub-Class I. P. SoLiDA — Containing {he hxmWes Millepores, of which there is no British genus amongst recent zoophytes ; and TuhuUporea which contains Tubulipora only.

74

CLASSIFICATIONS OF ZOOPHYTES.

Sub-Class II. P. Membranacea — in which are the three families — 1. P. opercuUfera, of which the British genera are Es- chara, Retepora, Cellepora, Berenicea, Discopora,and Mem- branipora ; 2. P. cellaricea contains Flustra, Cellaria, Tri- cellaria, Acamai-chis, Bicellaria, Crisia, Gemicellaria, Uni- cellaria, Catenicella ; 3. Ser'tulariccea — arranged~thus : —

( Anguinaria.

'tubular, with a rounded aperture } Tibiana.

(^ Tubularia. f Coryne.

campanulate < Campanularia.

Cells, -^ (^Laomedea.

, J Serialaria.

I Plumiilaria.

not tubulous,

i Sertularia.

paired -| Biseriaria.

(^ Dynamena.

7 X- 1 i. 1 1 J fCymodocia.

denticulate, whorled -\ \ ^ ^ ■

[ Antennularia.

denticulate, scattered Thoa.

Sub-Class III. Sub-Class IV.

P. DUBiA — Cristatella, Pluraatella, Alcyonella. P. NUDA — Hydra.

Class— ZOOPHYTARIA.

Body rather large and somewhat variable in shape, furnished with a

single circle of pinnated tentacula of determinate number ; the

ovaries internal.

Family 1. Tuhijiorcea — divided into two sections, (1.) envelope fleshy — with the genera Cuscutaria, which is the same as Valkeria of Fleming, Telesto, Cornularia, and Claviilaria, of which last three we have no na- tive species : (2.) envelope calcareous — Tubipora.

Family 2. Corallia — Coi'allium, Isis, Gorgonia, Eunicea, Prim- noa, Antipathes, &c.

Family 3. Pennahdaria — represented by Pennatula of Lin. with the various genera into which it has been por- tioned.

Family 4. Alcyonaria — Lobnlaria, Alcyonium, Cydoniura, Pulmo- nellum, Cliona.

Type II.

AMORPHOZOA.

Bodies organized, animal, shapeless or without a determinate form,

CLASSIFICATIONS OF ZOOPHYTES. 75

pierced with oscula and numerous pores, but without mouths or distinct individual animals, always adherent, and composed of a fi- bro-gelatinous substance, intermixed or not with calcareous or si- liceous spicula, with internal buds or gemmules not localized. This embraces the sponges only, divided into the following- genera — Alcyonellum, Spongia, Calcispongia, Halispongia, Spongilla, Geo- dia, Cseloptychium, Siphonia, Myrmeciura, Scyphia, Eudea, Hallir- hoa, Hippelimus, Cnenimidium, Lymnorea, Chenendopora, Tragos, Manon, Jerea, Tethium.

PSEUDOZOA.

Organized bodies not animal but vegetable.

Class I. Calciphytje. Family 1 . Corallince — Corallina, Jania, and Flabellaria are British

genera. Family 2. Fucoidece — of which there are no native examples.

When some years since I planned this history of our native zoophytes these were all the classifications that the books ac- cessible to me furnished for my purpose, but their imperfections and incongruities had been made so apparent in the progress of discovery, that I was induced to devise that one for my guid- ance which is here adopted. This method, drawn up with- out any foreknowledge of it, is in its main features similar to that proposed by Audouin and Milne-Edwards ;* and from this co- incidence I feel the more assured that it will be found in closer harmony with the structure of the animals than any of its pre- decessors, and not less difficult in its practical applications. It is then proposed to divide the British zoophytes in the first place into the following sub-classes and orders, whose families and genera will be found characterized under their respective heads.

Sub-Class I. RADIATED ZOOPHYTES.

Body contractile in every part, symmetrical ; mouth and anus one ; gemmiparous and oviparous. Order I. Hydroida. Polypes compound, rarely single and naked,

* Recherches pour servir a I'Histoire Nat. du Littoral de la France, Vol. i. p. 73—6,— Ann. des Sciences Nat. Part. Zool. vi. 1.5, 16 ; and Lam. Anira. s. Vert. ii. 104. 2de edit. Paris, 1836.

76 CLASSIFICATIONS OF ZOOPHYTES.

the mouth encircled with roug-hish filiform tentacula ; stomach with- out proper parietes ; intestine 0 ; anus 0 ; rei^roductive gemmules pullulating- from the body and naked, or contained in external vesi- cles. Poli/pidcms horny, fistular, more or less phytoidal, fixed, ex- ternal. Marine, excepting Hydra., which is lacustrine.

Order II. Asteroida. Polypes compound, the mouth encircled with 8 fringed tentacula; stomach membranous, with dependant vasculiform appendag-es ; intestine 0 ; anus 0 ; reproductive gem- mules produced interiorly. Polype-mass variable in form, free or permanently attached, carnose, generally strengthened with a horny or calcareous axis enveloped with the gelatinous or creto-gelatinous crust in which the polype-cells are immersed, and which open on the surface in a starred fashion with eight rays. Marine.

Order III. Helianthoida. Polypes single, free or permanently attached, fleshy, naked or encrusted with a calcareous Polypidom, the upper surface of which is crossed with radiating lamellae ; mouth encircled with tubulous tentacula ; stomach membranous, plaited ; intestine 0 ; anus 0 ; oviparous, the ovaries internal. Marine.

Sub-Class II. MOLLUSCAN ZOOPHYTES.

Pody non-contractile, and nan- symmetrical ; mouth and anus separate ; gemmiparous and oviparous.

Order IV. Ascidioida. Polypes aggregate, the mouth encircled with filiform ciliated retractile tentacula ; a distinct stomach, with a curved intestine terminating in an anus near the mouth ; ova in- ternal. Polypidoms very variable, — either horny, fistular and con- fervoid, or calcareous, membranous, or fibro-gelatinous, formed of cells connected and arranged in a determinate and usually quin- cuncial manner. Marine and lacustrine.

Additional Note. The only extensive series of experiments we have on the composition of Polypidoms are those of Mr Hatchett, published in the Philosophical Transac- tions for 1800, and the subsequent progress of zoological and chemical science requires a new investigation of the subject. The general results of Mr Hatch- ett's experiments are, " that the Madrepores and Millepores are formed of a ge- latinous or membranaceous substance, hardened by carbonate of lime, the differ- ence consisting only in the mode in which these materials are combined : that in the Tubipora, Flustra and Corallina, some phosphate of lime is mixed with the carbonate of lime : that in the Isis the basis is a regularly organized mem- branaceous, cartilaginous and horny substance, hardened by carbonate of lime, one species only (the Isis ochracea) yielding also a small proportion of phos- phate of lime. That the hardening substance of the Gorgonia nobUis is like- wise the carbonate of lime, with a small portion of phosphate ; but that the matter forming the membranaceous basis consists of two parts, the interior being

o

CLASSIFICATIONS OF ZOOPHYTES. 77

gelatinous, and the external a complete membrane, so formed as to cover the stem in the manner of a sheath or tube. That the other Gorgonife consist of a horny stem coated by a membrane, which is hardened by carbonate of lime. That the sponges are of a natme similar to the horny stems of the Gorgoniee, and only differ from these and from each other by the quality of texture. And lastly, that the Alcyonia are likewise composed of a soft flexible membranaceous sub- stance, very similar to the cortical part of some of the GorgonicC ; and in like manner slightly hardened by carbonate, mixed with a small portion of phosphate of lime.

" From this mass of evidence we collect, in general, that the varieties of bone, shell, coral, and the numerous tribe of Zoophytes with which the last are con- nected, only differ in composition by the nature and quantity of the hardening or ossifying principle, and by the state of the substance with which this princi- ple is mixed or connected ; the gluten, or jelly, which cements the particles of carbonate or phosphate of lime, and the membrane, cartilage, or horny substance which serves as a basis, appearing to be only modifications of the same sub- stance, which progressively graduates from a viscid liquid, or gluten, into a ge- latinous substance, which again, by increased inspissation, and by the more or less perfect degrees of organic arrangement, forms the varieties of membrane, cartilage, and horn, which, it seems, form the peculiar differences of the several species." Abst. Phil. Trans, i. 25-26. There is a very full analysis of Hatch- ett's paper in Thomson's Syst. of Chem. v. p. 539, et seq. The paper itself will be found in Phil. Trans, abridg. xviii. p. 706.

Raspail has ascertained that a large proportion of iron enters into the com- position of the Alcyonella, which he thinks may be derived from the habitat, the zoophyte developing itself upon ferruginous rocks. The iron holds the same po- sition in the polypidom, that the carbonate of lime does in the Oculinae, or the crystals of silex in the sponges. Its great proportional quantity may be esti- mated from the following experiment " Un fragment sec du Polypier faisait

devier de trois degres la nouvelle aiguille aimantee, construite par notre collegue, M. Saigey, quoique ce fragment ne presentat a raiguille qu'une surface d'un cen- timetre environ. Cette deviation paraitra enorme si Ton veut se rappeler que I'Alcyonelle est une substance spongieuse extraordinairement legere ; ajoutes a I'importance de ce resultat que le fer parait y exister a I'etat de trioxide, puisqu' avant comme apres I'incineration, la substance est egalement rougeatre, et qu'en consequence son influence sur I'aiguille aimantee serait infiniment faible, si le fer existait en faible quantite dans son tissu lache et spongieux." — Mem. de la Soc. d'Hist. Nat. iv. p. 119.

" Non tamen, post tot ac tantos scriptores, pigebit meam quibusdam locis posuisse sententiam. Neque enim me cujusquam sectae, velut quadam super-

stitione imbutus, addixi : sicut ipse pliurium in unum confero inventa,

ubicumque ingenio non erit locus, curse testimonium meruisse contentus." — QuintiUan. iii. i.

BRITISH ZOOPHYTES.

PART II.

ZOOPHYTA HyDROIDA.

Fig. 8.

Plumularia Catharina.

" Involved in sea-wrack, here you find a race,

" Which science doubting, knows not where to place ;

" On shell or stone is dropp'd the embryo seed,

" And quickly vegetates a vital breed."— Cra66e.

" Interpone tiiis interdum gaudia curis, " Ut possis animo quemvis Sufferre laborem."'

Catullus.

" Early habits have made me prefer the entertainment resulting from the ex- position of the beauties of Nature, and the delight to be derived from examining the works of the Creator, in which infinite wisdom and intelligence are dis- played, to all other amusements." — Sir Everard Home.

" The works of the Lord are great, and sought out of all them that have pleasure therein." — Psalmist.

" And many disappointments could not cure " This born obliquity, or break the lure " Which this strong passion spread."

H. Taylor.

" Whate'er you study, in whate'er you sweat,

" Indulge your taste

" He chooses best, whose labour entertains " His vacant fancy most."

Armstrong.

ZOOPHYTA BRITANNICA.

ORDER I. Z. HYDROIDA.

Character. Polypes compound, rarely single and naked, the mouth encir- cled ivith roughishjiliform tentacida ; stomach without proper pa- rietes ; intestine 0 ; anus 0 ; reproductive gemmules pullulating

from the body and naked, or contained in external vesicles.

Polypidoms horny, Jistular, more or less phytoidal, fixed, external.

Observations.

" As for your pretty little seed-cups or vases, they are a sweet confirmation of the pleasure Nature seems to take in su- peradding an elegance of form to most of her works, wherever you find them. How poor and bungling are all the imitations of art ! When I have the pleasure of seeing you next, we will sit down, nay kneel down if you will, and admire these things."*" Thus did Hogarth — our great moral painter — write to Ellis in evident reference to the zoophytes of the present order ; and he must indeed be more than ordinarily dull and insensate who can examine them without catching some of the enthusiasm of the artist. They excel all other zoophytical productions in delica- cv and the graceful arrangement of their forms, some borrowing the character of the prettiest marine plants, others assuming the semblance of the ostrich-plume, while the variety and elegance exhibited in the figures and sculpture of their miniature cups and chalices is only limited by the number of their species.

The Hydroida vary from a few lines to upwards of a foot in

* Lin. Corresp. Vol. ii. p. 44. F

82 ZOOPHYTA HYDKOIDA.

height. They are all, with the exception of the hydra or fresh- water polype, marine productions, and are found attached to rocks, shells, sea-weed, other corallines, and to various shell-fish. Many of them appear to be indiscriminate in their choice of the object, but others again make a decided preference. Thus Thuiaria thuja prefers the valves of old shells, Thoa helicina is more partial to the larger univalves, Antennularia antennina grows on rocks, Campanularia genieulata delights to cover the broad frond of the tangle with a fairy forest peopled with its myriads of busy polypes, while the Sertularia pumila rather loves the more common and coarser wracks. The choice may in part be dependent on their habits, for such as are destined to live in shallow water, or on a shore exposed by the reflux of every tide, are in general vegetable parasites ; while the species which spring up in the deep seas must select between rocks, corallines or shells, the depths at which they are found being too great for the veofetation of sea-weed.*

The polypidoms are confervoid and more or less divided, the ramifications being disposed in a variety of elegant plant-like forms. The stem and branches are alike in texture, slender, horny, fistular, and almost always jointed at short and regular intervals, the joint being a mere break in the continuity of the sheath without any character of a proper hinge, and evidently formed by regular periodical interruptions in the growth of the polypidoms. Along their sides, or at the extremities, we find the denticles or cup-like cells of the polypes arranged in a de- terminate order, either sessile or elevated on a stalk, (Fig. 9, a.) Though of the same substance, the cell is something more than a simple expansion of the stem or branch, for near its base there is a distinct partition or diaphragm on which the body of the polype rests, with a plain or tubulous perforation in the centre, through which the connection between the individual polype and

* Lamouroux says, — " We find some polypidoms placed always on the south- ern slopes of rocks and never on that towards the east, west, or north. Others, on the contrary, grow only on these exposures, and never on the south. Some- times their position is varied according to latitude, and the shores inclined to- wards the south, in temperate or cold countries, produce the same species as the northern exposures in equatorial regions ; in general their branches appear di- rected towards the main sea."— Corall. Flex. Introd. p. L.

ZOOPHYTA HYUROIDA.

83

the common medullary pulp is retained, (Fig. 9, h.) * Besides the cells there are found, at certain seasons, a larger sort of ve- sicles, readily distinguished from the others by their size and the irregularity of their distribution.— The more robust tribes grow erect, and, beuig flexible and elastic, yield readily to the waves and currents ; but some of the very delicate species avoid a shock for which they are unequal by creeping along the surface.

Fiff. 9.

The polypidoms, when dried, are for the most part of a yel- lowish or horn colour. " When they are immersed in water, they recover the same form they appeared in when fresh in the sea ; and soon become filled with the liquid. This gives them a semitransparent amber colour, and makes them very elastic.""!* Their material appears to be analogous to horn or condensed

• Lister, in Phil. Trans. 1834, p. 371. t Ellis, English Corallines, p. 3.

84 ZOOPHYTA HYDROIDA.

albumen, which is moulded into a homogeneous investing sheath, for the protection of the semifluid pulpousbody. It seems to be in fact a sort of hardened epidermis, at first in contact and partial ad- hesion with the living interior pulp, from which it is subsequent- ly detached, in the natural progress of its consolidation, by a process of shrivelling in the soft matter, and by the motions and efforts of the polypes themselves.* Link says that the experi- ments he has made on the Plumularia falcata and the Sertularia cupressina have led him to adopt the opinion of Cavolini and Schweigger, that this sheath is vascular and organized, for, un- der a very powerful magnifier, he has seen coloured vessels ra- mified in the stem and branches of these polypidoms. He is also certain that their stems are often increased with age by con- centric layers, and that the calcareous matter is deposited in true cells.-|- These observations are intended to support the theory of the independent growth of the polypidom from innate living motions or a vegetative principle, but notwithstanding Link's high authority, I would caution the student against a too hasty reception of the facts. They are at variance with the experi- ments of Ellis, Grant and Blainville ; nor does Dr Fleming nor Mr Lister appear ever to have noticed traces of vascularity in these objects during their microscopical inquiries ; and I have in vain sought for the existence of vessels^ in some transparent species, as Sertularia rosacea and Campanularia gelatinosa, where it seemed likely they would most easily be detected. Dr Fleming, from observations of a different kind, as e. g. the con- version of cells into vesicles and of these into branches, or even of the polypes themselves into branches, in the Plumularia bullata and Campanularia gelatinosa, has come to the conclusion that the polypidom is, in its mode of growth, analogous to hone^ " a circumstance on which its apparent vegetating power de~ pends"j ; but since I suspect the accuracy of the alleged ob- servations, and cannot, on reflection, perceive where the analo- gy between these horny sheaths and bone lies, I am necessitated

* See Lister's Observations in Phil. Trans. 1834, p. 374; and Lam. Anim. s. Vert. ii. 119. 2de edit. Milne- Edwards also tells us that there is a canal down the centre of the soft pulp in which the circulation is carried on. Is not this a transcendental piece of anatomy ?

f Ann. des Sciences Nat. Part. Bot. Vol. ii. p. 321.,

X Memoirs of the Wernerian See. Vol. v. p. 303 — G.

ZOOPHYTA HYDROIDA. 85

to believe tlio polypidoni to be extravascular and inorganic — the result of an exudation from the interior pulp, and dependent, on this for its form and growth, however varied this may be. In the reproductive gemmule there are two substances, viz. the pulp and the thin cuticle or membrane, the latter of which is the germ of the future arborescent or cellular polypidom : by the growth of the pulp the membrane is distended and moulded into a cell, or pushed upwards in the form of a shoot, in which, after a time, the pidp is arrested in its growth longitudinally, swells out, and is developed into an animated polype, furnished with ten- tacula, a mouth, and digestive organs. Bursting the cell at the point which becomes the future aperture, it there dis- plays its organs, and begins the capture of its prey, for, unlike higher organisms, the polype is at this the period of its birth as large and as perfect as it ever is at any subsequent period, the walls of the cell having become indurated and unyielding, and setting a limit to any further increase in bulk. The growth being thus hindered in that direction, the pulp, incessantly in- creased by new supplies of nutriment from the polype, is con- strained and forced into its original direction, so that the extre- mities of the tube, which have remained soft and pliant, are pushed onwards, the downward shoot becoming a root-like fibre, and the upper continuing the polypidom, and swelling out as before, at stated intervals, into cells for the new developement of other polypes. The polypidom then, however like unto cer- tain vegetables in appearance, has, as Ellis said, nothing vege- table about it, but is entirely an animal production, and excret- ed by the animated pulp which fills its whole interior. Ellis and his followers are only so far wrong, that they have attributed to the polypes themselves what is actually due to the pulp. The latter is that from which the polypidom is exuded ; for, indeed, the cell always precedes the existence of the polypus which is developed within it ; while the polypidom begins to be develop- ed from the gelatinous substance of the reproductive gemmules before any polypes are formed, and it continues to be develop- ed and extended by the fleshy mass of the zoophyte, whether polypes are developed in the cells or not. " There is but one life, and one plan of developement, in the whole mass ; and this depends not on the polypi, which are but secondary and often

86 ZOOPHYTA HYDROIDA.

deciduous parts, but on the general fleshy substance of the

body."*

The polypes are placed in the cells within which, with the

exception of the Tubularise, they can hide themselves entirely

when danger threatens. When at rest and in their native sites,

they expand their tentacula and push them far beyond the rim

of their cups, in readiness to arrest any small worm or crusta-

ceous insect which may float within their circle.

" Utque sub sequoribus deprensum polypus hostem " Contiiiet, ex omni dimissis parte ilagellis."

Ovid. Met. vi. 366.

These tentacula are always simple but roughish, (Fig. 9 c,) and in the centre of the disk round which they are arranged we perceive the oral aperture (d,) leading to a stomachical cavity without intestine or other chylopoetick viscus. The body is somewhat globular, soft and irritable ; and it is prolonged posteriorly down the stalk or tube to be united with the central pulp which fills the branches and stem, (e,) so that in this manner all the po- lypes of the same polypidom are connected together by a living thread, and constitute a family whose objects and interests are identical, and whose workings are all regulated by one harmo- nious instinct.

" Unconscious, not unworthy, instruments,

By which a hand invisible was rearing

A new creation in the secret deep." Or if, with Linnaeus and Cuvier, we suppose that the " whole composure makes one animal," this may be described as a sort of hydra divided, after the manner of a tree, into many or in- numerable branches, from each of which pullulate one or more armed heads to capture and digest the prey that is to serve for the nutriment of their common trunk.

The reproductive gemmules of Tubularia and Coryne are generated in the interior and extruded near the base of the ten- tacula ; but in all the other genera they are produced in exter- nal vesicles, which were therefore appropriately named by Ellis the matrices or ovaries, and which we have already mentioned as being larger than the cells and irregular in their distribution. They are produced at certain seasons only, most commonly in spring, and fall off" after the maturity and discharge of their con-

* Grant's Outlines of Comp. Anatomy, p. 14.

ZOOPHYTA HYDROIDA. 87

tents. * The number of the gemmules in each vesicle, and their shape, varies in every species. In the vesicle they are connected to a central placentular column, though there are some exceptions to this, and when mature they escape outwards by a disruption or fall of the lid which closes the top, being extruded in succession and, in some cases at least, after intervals of some hours. It appears to be deducible from some figures of Ellis, f rather than from his expressions, X which are equivocal, that the ovules are sometimes developed into perfect polypi before their expulsion from the matrix, but the fact, though not incredible, needs confirmation, and it is certain that their birth in the ovi^ form condition is the general rule. At this period they are clothed with cilia, as Ellis has figured them, § and as Professor Grant first distinctly brought into view ; and by means of the rapid vibrations of these minute organs they are carried to and fro through the water for some time, varying from a few hours to two or three days, until, having at length in due course settled on a proper site, they throw out, in the man- ner of a vegetable seed, a root-like fibre to fix themselves, and then push up a shoot as a commencement to the fu- ture polypidom. || Polype-cells and polypes are rapidly evolv- ed on the sides of this shoot, and nourishment being now re-

* So that Hedwig's axiom, adopted by M. Virey, " that the reproductive organs of animals are contijiuous with the life of the individual, while the repro- ductive organs of perennial plants, when their functions have been performed, are thrown off, and replaced hi the succeeding season by others,"— must be re- ceived with some limitations — See Tiedemann's Comp. Physiology, p. 7G.

t Corall. pi. V. lig. A. t Corall. Introd. p. x.

§ Corall. pi. xxxviii. fig. B.

II Mr Lister has minutely described the ova of Campanularia gelatinosa. " The ova were roundish, and consisted of two portions ; the outer and more transparent, that might be called the white, inclosing an inner bag filled with particles in fluid like those in the currents of the stem, and connected with them by the cord. The current and agitation were seen in the inner bags only, and the flow into and from them alternately along the cord was strongly marked." As they approach maturity " the ova became more opaque, which hid the changes that might be taking place within them. The number in a full ovai-y was about seven." When mature they emerged from the cell " in succession at an average interval of six hours. The protrusion took about a quarter of an hour, and was connnonly preceded by a transparent projection, like torn mem- brane, before the end of the ovary, and a few active particles in tlie water." —Phil. Trans. 1834, n. o75.

88 ZOOPHYTA HYDROIDA.

ceived from an external source, and circulating throuoh the whole animal, there is not merely an upward growth, but creep- ing tubes, " full of the same living medullary substance with the rest of the body," are projected from the base along the surface of the object of fixture. " These tubes not only secure it from the motion of the waves, but likewise from these rise other young animals or corallines, which growing up like the former, with their proper heads or organs to procure food, send out other adhering tubes from below, with a further increase of these many-headed branched animals ; so that in a short time a whole grove of vesicular corallines is formed, as we find them on oysters, and other shell-fish, when we drag for them in deep water." *

There are many facts which prove that the growth of these polypidoms is very rapid, but not more so than might be anti- cipated when it is remembered how vast is the number of polype architects ; and no sooner is a new branch extended than it be- comes almost simultaneously a support of new workers which, with " toil unwearyable," add incessantly to the materials of in- crease. Their duration is various : some have only a summer's existence, as Campanularia geniculata ; many are probably an- nual, and the epiphyllous kinds cannot at most prolong their term beyond that of the weed on which they grow : but such as attach themselves to rocks are probably less perishable, for their size and consistency seem to indicate a greater age : it is thus with the Tubularise and some of the compound Sertu- lariadse.

But the life of the polypes considered abstractedly is proba- bly in no instance coetaneous with the duration of the polypi- dom, for the lower parts of this become, after a time, empty of pulp and lifeless, and lose the cells inhabited by the polypes,

" Ellis and Solander's Zoophytes, p. 33.

'* New buds and bulbs the living fibre shoots

" On lengthening branches, and protruding roots ;

" Or on the father's side from bursting glands

" The adhering young its nascent form expands ;

" In branching lines the parent-trunk adorns,

" And parts ere long like plumage, hairs, or horns."

Darwin's Temple of Nature, Canto Li. 4

ZOOPHYTA HYDROIDA. 89

which, in an old specimen, are to be found in a state of activity only near the summit, or on the new shoots. The Thuiaria thuja affords a remarkable example of this fact ; the branches which carry the polypes dropping off in regular succession as younger ones are successively formed, so that the polypidom re- tains, throughout its whole growth, the appearance of a bottle- brush, the naked stem and the branched top being kept in every stage in a due proportion to each other. Sertularia argentea, Plumularia falcata, &c. are subjected to the same law, — the pri- mary polypiferous shoots being deciduous, so that in them also the stalk becomes bare, while the upper parts are graced with a luxuriant ramification loaded with tiny architects. But in our eagerness to generalize, let us not forget that there are some species, as Sertularia pumila, abietina, &c., in which this pro- cess of successive denudation is not observable, — perhaps, how- ever, because of their form, which is not of a kind to be altered by it, and hence unnoticeable, or because the duration of the whole is too fugitive to permit the law to produce a visible ef- fect.

There are facts which appear to prove that the life of the in- dividual polypes is even more transitory than their own cells ; that like a blossom they bud and blow and fall off or are absorb- ed, when another sprouts up from the medullary pulp to occupy the very cell of its predecessor, and in its turn to give way and be replaced by another. When speaking of flexible corallines Ijamouroux says, " Some there are that are entirely covered with polypi through the summer and autumn, but they perish with the cold of winter : no sooner, however, has the sun resum- ed his revivifying influence than new animals are developed, and fresh branches are produced upon the old ones."* Of the Tu- bularia indivisa. Sir John G. Dalyell tells us that " the head is deciduous, falling in general soon after recovery from the sea. It is regenerated at intervals of from ten days to several weeks, but with the number of external organs successively diminishing, though the stem is always elongated. It seems to rise within this tubular stem from below, and to be dependent on the pre- sence of the internal tenacious matter with which the tube is oc-

* Corall. Flex- p. xvi.

90 ZOOPHYTA HYDROIUA.

cupied. A head springs from the remaining stem, cut over very near the root ; and a redundance of heads may be obtained from artificial sections, apparently beyond the ordinary provisions of nature. Thus twenty-two heads were produced through the course of 550 days, from three sections of a single stem."* The observations of Mr Harvey on the same, or a very nearly allied, species of zoophyte confirm the experiments of Sir J. G. Dal- yell, so far as these have i-eference to the deciduousness of the polypes and their regeneration ; -f- and it seems to me not alto- gether unwarrantable to infer a like temporary existence and re- vival in those of the Sertulariadse from a reflection on the ex- periments of Mr Lister, — incomplete certainly, but which prove that under certain circamstances their polypes disappear by a pro- cess of internal absorption,;]: and under convenient circumstances would probably have been renovated, as I have witnessed this re- sult in similar experiments. On Saturday, May 28th 1837, a spe- cimen of Campanularia gelatinosa was procured from the shore, and after having ascertained that the polypes were active and entire, it was placed in a saucer of sea-water. Here it remained undis- turbed until Monday afternoon, when all the polypes had disap- peared. Some cells were empty or nearly so, others were half-fil- led with the wasted body of the polype, which had lost, however, every vestige of the tentacula. The water had become putrid, and the specimen was therefore removed to another vessel with pure water, and again set aside. On examining it on the Thursday,

* Edin. New Phil. Joum. xvii. p. 415.

t " The most singular circumstance attending the growth of this animal, and which I discovered entirely by accident, remains to be mentioned. After I had kept the clusters in a large bowl for two days, I observed the animals to droop and look unhealthy. On the third day the heads were all thrown off, and lying on the bottom of the vessel ; all the pink colouring matter was deposited in the form of a cloud, and when it had stood quietly for two days, it became a very line powder. Thinking that the tubes were dead I was going to throw them iiway, but I happened to be under the necessity of quitting home for two days, and on my return 1 found a thin transparent film being protruded from the top of every tube : I then changed the water every day, and in three days time every tube had a small body reproduced upon it. The only difference that I can dis- cover in the structure of the young from the old heads, consists in the new ones wanting the small red papillce, and in the absence of all colour in the animal." — Proceed. Zool. Soc. No. 41, p. 55.

I Phil. Trans. 1834, p. 374, 376.

3

ZOOPHYTA HYDKOIDA. 91

(June 1st) the cells were evidently filling again, although no tentacula were visibly protruded, but on the afternoon of Friday (June 2d) every cell had its polype complete, and displayed in the greatest perfection. Had these singular facts been known to Linnteus, how eagerly and effectively would he have impres- sed them into the support of his favourite theory ! Like the flowers of the field the heads or " flores" of these polypidoms expand their petaloid arms, which after a time fall like blighted blossoms off a tree ; — they do become " old in their youth," and rendered hebetous and unfit for duty or ornament by age or accident, the common trunk throws them off, and supplies its wants by ever-young and vigorous growths. The phenomena are of those which justly challenge admiration and excuse a so- ber scepticism, so alien are they to all we are accustomed to ob- serve in more familiar organisms ; but besides that faithful ob- servation renders the facts undeniable, a reflection on the history of the Hydra might almost have led us to anticipate such events in the life of these zoophytes. " Verily for mine owne part, the more I looke into Nature's workes, the sooner am I induced to beleeve of her even those things that seem incredible."

I arrange the British species of this order under the follow- ing families and genera :

Family I. HYDRAID.F:. Polypes gemmiparous, the young pullulating from the body of the

parent.

1. Hydra. Polypes naked, single, locomotive.

Family II. TUBULARIAD/E. Polypes gemmiparous, the gemmules naked, pullulating from the

bases of the tentacula. * No Poly2)idom.

2. CoRYNE. Polypes naked, the tentacula filiform.

3. Hermia. Polypes tunicated, the tentacula with glandular tips.

** A distinct polypidom.

4. TuBULARiA. Polypes not retractile within cells : Polypidoms listular, simple or branched.

92 ZOOPHYTA HYDKOIDA.

Family HI- SERTULARIADiE.

Polypes gemmiparous, the gemmules enclosed in external ovarian persistent vesicles scattered on the polypidom. * Polype-cells sessile. 5. Thoa. Cells indistinct, tubular or campanulate, alternate. G. Sertularia. Cells biserial, vasiform, short, erect, the aper- tures everted.

7. Thuiaria. Cells biserial, tubular-conical, imbedded, the aper- tures looking- forward.

8. Plumularia, Cells uniserial ; the branchlets plumose or pec- tinate.

9. Antennularia. Cells uniserial ; the branchlets whorled.

** Polype-cells on ringed stalks.

10. Laomedea. Cells from a thickened joint of the stem, alter- nate, campanulate.

11. Campanularia. Cells continuous with the stem, irregular

or whorled, campanulate.

Fig. 10.

Fig. 11.

I. ZOOPHYTA HYDROIDA.

FAMILY I. HYDRAIDiE.

1. Hydra,* Linnaeus.

Character. — Polypes locomotive, single, naked, gelatinous, sub-cylindrical, hut very contractile and mutable inform, the mouth encircled with a single series of granulous filiform tentacula.

1. H. viRiDis, grass-green ; body cylindrical or insensibly

narroived downwards ; tentacula 6 — 10, shorter than the body.

Woodcut, No. 4, page 37.

Polyi)es verds, Trembley, Mem. 22, pi. 1, fig. 1 ; pi. 3, fig. 1 — 10

Fresh-water Polypus, Trembley, in Phil. Trans. Abridg. viii. 623. Folhes,

in ibid. 676. pi. 17, and pi. 18, fig. 1 — 3 Hydra viridis. Lin.

Faun. Suee. 367, No. 1283. Lin. Syst. 1320. Mull. Verm. I. ii. 13. Zool. Dan. prod. 230, No. 2783. Berk. Syn. i. 221. Ure's Rutberg. 232. Turt. Gmel. iv. 691. Turt. Br. Faun. 218. Lam. Anim. s. Vert. ii. 60. Steio. Elem. ii. 452. pi. 12, fig. 4, 5. Blumenhach's Man. 275. pi. 1 . fig. 10. Base, Vers ii. 274. Stark, Elem. ii. 443. Woodward in Mag. Nat. Hist. iii. 349, fig. 89. Roget, Bridgew. Treat, i. 162, fig. 59, and 176—8, fig. 73—76. Adams on the Microscope, 399, pi. 21, fig. 5.

* "TtTga — properly " a water serpent," but the name has been appropriated to the monster of Lake Lerna, fabled to have 50 or 100 heads, of which no sooner was one of them cut off, than two sprouted out in its place. From this property Linnaeus was obviously led to apply the name to the animalcules in question.

94 Z. HYDROIDA. Hydra.

Carus, Comp. Aiiat. tab. 1. fig. 1 H. viridissima, Pall. Eleiich. 31.

Third sort of Polype, Baker, Polyp. 19 c. fig Le Polype vert,

Cuv. Reg. Aiiim. iii. 293. L'Hydre verte, Blainv. Actinol. 494. pi.

85, fig. 1. Hab. Ponds and still waters, common throughout England, and the south of Scotland. In almost all the parishes in the vicinity of Glasgow, Ure.

The polypes of this species differ from the following, " not only in colour, but likewise in their arms, which were much shorter in pro- portion to their bodies, capable of but little extension, and narrower at the root than the extremity, which is contrary to the other spe- cies. Their arms were so short, they could not clasp round a very small and slender worm, but seemed only to pinch it fast, till they could master and devour it, which they did with as much greediness as any. I imagined these polypes owed their green colour to some particular food, such as weeds, &c. and that they would lose it upon being kept to worms ; but I find myself mistaken, for they retain their greenness after some months as well as ever, and are now grown of a moderate size, extending sometimes three quartei'S of an inch ; their arms are also lengthened very much to what they were, and are of a lighter green than the body, their number eight, nine, or ten. The tail is very little slenderer than the body, but more spread at the end than the tails of other kinds." — Baker.

Pallas says that the offspring are produced from every part of the body, while Blainville thinks he has remarked that they shoot always from the same place, " au point de jonction de la partie creuse et de celle qui ne Test pas." Blainville is candid enough, however, to in- form us that Professor Van der Hoven had made some observations adverse to his opinion ;* and our own are certainly in accordance with those of Pallas and of the Professor of Leyden.

Trembley is careful to tell us that he discovered this species in June 1740, nor can we smile at the particularity of the record when we remember that the discovery is the foundation of his immortal fame.f It was first observed in England in the spring of 1743 by a Mr Du Gane of Essex. It appears to be a hardy animal. I have kept it for more than twelvemonths in a small vial of water unchanged during the whole of that time, and it remained lively, and bred freely, feed- ing on the minute Entomostraca confined with it, and which propa-

• Bulletin des Sc. Nat. xvi. 337.

f " Trembley (Abraham), de Geneve, ne en 1710, mort en 1784; immortel par le decouverte de la reproduction du polype." — Cuvier, Reg. Animal, iii. 422. — Blumenbach also informs us that his observations on this polype first led him to his ingenious investigations on the Nisus formativus.

Hydra. Z. HYDROIDA. 95

gating- much more abundantly, furnished a good supply of what was evidently a favourite food.

2. H. VULGARIS, orange-broicn or sometimes oil-green ; body cylindrical ; tentacula 7-12, as long or longer than the body,

Plate I.

Polypes de la seconde espece, Tremb. Mem. pi. 1, fig. 2, 5 ; pi. 2. fig. 2 ; pi. 6. fig. 2 and 8; pi. 8. fig. 1—7; pL iO. fig. 1—7 ; pi. 11, 12, 13.

figs. omn. partly copied in Adams, Micros, 399, pi. 21. fig. 6 Hydra

vulgaris, Pall. Elench. 30. Ellis in Phil. Trans. Ivii. 430. Ellis and

Soland. Zooph. 9 H. grisea, Lin. Syst. 1320. Mull. Zool. Dan.

Prod. 2.30, No. 2784. Verm. i. ii. 14. Ure's Rutherg. 233. Berk. Syn. i. 222. Turt. Gmel. iv. 692. Turt. Brit. Faun. 218. Blumenb. Man. 295. Stew. Elem. ii. 452. Lam. Anim. s. Vert. ii. 60. Bosc, Vers ii. 275. Stark, Elem. ii. 443. Templeton in Mag. Nat. Hist. ix.

418 — H. brunnea, Templeton, loc. cit. 417. fig. 56 First sort of

Polype, Baker, Polyp. 17. c. fig L'Hydre commune, Blainv. Acti-

nol. 495. Hab. Weedy ponds and slowly running waters Probably common in all parts of the kingdom.

On comparing the descriptions of the authors quoted above, I am led to conclude that this species is either subject to much variety, or that two species have been confounded together, and given rise to a discrepancy which seems otherwise irreconcileable. My own expe- rience inclines me to the latter supposition, but since I have had no opportunities of making observations on specimens from different and distant localities, I deem it more prudent to indicate what appear to be two species as only varieties of the vulgaris, until the point can be settled by more leisured naturalists.

Var. a. aurantia, light reddish-brown or orange-coloured ; tenta- cula not longer than the body. Fig. 2.

Var. b. grisea, light olive-green ; tentacula paler and longer than the body. Fig. 1.

The first is by much the commoner, and does not exceed the H. yiridis in size, which it resembles also in its habits and form. It is always of an orange, brown, or red colour, the intensity ofWie tint depending on the nature of the food, on the state of the creature's repletion, becoming even blood-red when fed upon the small crim- son worms and larvse which usually abound in its haunts.* The ten-

* " I have found a bright red Hydra rather abundant on Putney Heath, near London. It does not much differ, except in colour, from the green one." J. E.Gray in lit. May 6, 1833 — See Trembley's Mem. p. 47, and 128.

96 Z. HYDROIDA. Hydka.

taenia in all my specimens have never exceeded the length of the body, are usually seven or eight in number, and taper to the point insensibly. Every part of the body is generative of young, which may frequently be seen hanging from the parent at the same time in different stages of their growth. Baker's figui'e represents this va- riety very well.

The second is a larger animal and comparatively rare, less sensible to external impressions, and of a more gracile form. Its colour is a dilute olive-green with paler tentacula, which are considerably long- er than the body, and hang like silken threads in the water, waving to and fro without assuming that regular circular disposition which they commonly do in the H. viridis. I have not observed more than one young at a time, pullulating from near the middle of the body, and after this has attained a certain growth, the polype has the appearance of being dichotomously divided.

Dr Fleming's Hydra vulgaris, Brit. Anim. 553, embraces this and the preceding, as well as the following species, which are consi- dered the mere variations of one protean original ; —

" Facies non omnibus una, Nee di versa tamen :" —

but the conviction of their permanent distinctness has been forced upon me by a long continuous observation of individuals in a state of confinement. Had, however, personal observation been wanting, the same conclusion would have been willingly adopted on the paramount authorities of Trembley and Baker, who had very carefully studied these creatures ; and Pallas speaks very decidedly to the same pur- port. " Species Hydrae a Linnaeo* pro varietatibus habitas, a Raese- lio primum bene determinatas adoptavi, cum de trium priorum con- stantia, propi'ia me experientia certissimum reddiderit." — Elench. 29.

3. H. FUSCA, hrown or griseous ; inferior half of the body sud- denly attenuated ; tentacida several times longer titan the body. Vignette, No. 11, page 93. Polypes a long bras, Tremh. Mem. pi. 1. fig. 3, 4, 6 ; pi. 2. fig. 1, 3, 4 ; pi. 3, fig. 11 ; pi. 5, fig. 1-4; pi. 6, fig. 3-7, 9, 10 ; pi. 8. fig. 8, 11 ; pi. 9. copied in Adams, Micros. 399, pi. 21, fig. 7, 8 ; pi. 2-3, A. B ; pi. 24, A,

B. fig. omnes. Cuv. Reg. Anim. ill. 295 Long armed fresh-water

Polype, Ellis, Corall. xvi. pi. 28. fig. C. (the tentacula shortened for the

conveniency of introducing them within the size of the plate.) Second

sort of Polype, Baker, Polyp. 18. c. fig Hydra oligactis, Pall. Elench.

29 H. fusca, Lin. Syst. 1320. Ellis and Soland. Zooph. 9. Berk.

In the lOtli edit, of Syst. Nat. p. 810, under the name oi Hydra Polypus,

Hydra. Z. IIYDHOIDA. 97

Syn. i, •2-21. Turt. Gmel. iv. 991. Blumcnb. Man. 275. Turt. Brit. Faun. 218. Stew. Elem. ii. 452. Lam. Anim. s. Vert. ii. 60. Bosc,

Vers, ii. 275. L'H. brune, Blainv. Actinol. 495.

Hab. Still waters in England, rare. In a pond at Hackney, Mr John Ellicot.*

" The tails of these are long-, slender, and transparent, and when placed before the microscope, a long- straight gut may plainly be dis- tinguished passing from the body-part or stomach to an opening at the end thereof. These are rather lighter coloured than the former, (H. vulgaris,) and have seldom more than six or eight arms, but those capable of great extension." — Baker.

Baker reckoned that his English exemplars were of a soi*t diffe- rent from those he had received from M. Trembley, but the only ap- parent difference lies in the greater shortness of the tentacula of the former, and this is a character liable to considerable variation, and in- sufficient of itself for specific distinction. The species has been beautifully illustrated in Trembley's " Memoires," by the pencil and graver of the celebrated Lyonet, for it is an interesting fact that all the figures, and most of the plates, which adorn the admirable book just mentioned, were drawn and etched by the author of the " Traite anatomique de la chenille du saule,"f and are indeed among the very earliest specimens of his extraordinary attainments in these arts.

It may be worth while to call attention to the remarkable resem- blance of the Hydra fusca to the Cucullanus cirratus of MuUer, Zool. Dan. tab. 38, fig. 1-7, which is an intestinal worm !

4. H. VERRUCOSA, pale cinereous ; body pedunculate, cam- paniform ; tentacula longer than the hody.

Hydra verrucosa, Templeton, in Mag. Nat. Hist. ix. 418, fig. 57.

Hab. Still waters, " In the pond at Cranmore (near Belfast,) Sept. 1812," J. Templeton, Esq.

" Of a pale cinereous hue, with six verrucated tentacula, of mode- rate length, and nearly equal thickness." " This species, when at

rest, assumes more of a campanulate form than any other species of the genus, except lutea and the following. The warts are not uni- formly diffused, as in pallens ; nor do the tentacula diminish much in size towards the tips." — Templeton.

* Elected F. R. S. Oct. 26, 1738; and the author of several papers on sub- jects in Natural Philosophy, published in the Phil. Trans, between the years 1745 and 1750. He was a watchmaker, and died in 1772.

t " Ouvrage qui est a la fois le chef-d'oeuvre de 1 'anatomic et celui de la gra- vure." — Cuvier.

G

98 Z. HYDROIDA. Hydiia,

** Marine species. 5. H. ? LiTTORALis, " white; head large ; about 10 extreme- ly short tentacula encircling the base." — Robert Jameson. *

Hydra lutea? Jameson, in Wem. Mem. i. 565— H. lutea, Flem. Brit.

Anim. 554 — H. corynaria, Templeton, in Mag. Nat. Hist. ix. 419, fig. 58.

Hah. Sea shore, adhering- to Fuci. Frith of Forth, Professor

.Jameson. " Found adhering- to Fucus vesiculosus, at White House

Point, Belfast Lough, Oct. 1810," J. Templeton, Esq.

The figure represents a branched animal with enlarged clavate heads encircled round the truncate apex, with tentacula rather short- er than the diameter. — To justify the change I have made in the name, it is only necessary to mention that nothing can be more cer- tain than that this species is not identical either with the Hydra lu- tea or corynaria of Bosc.

Observations.

Leeuwenhoek-|- discovered the Hydra in 1703, and the uncomrnon way its young are produced, and an anonymous correspondent of the Royal Society made the same discovery in England about the same time, but it excited no particular notice until Trembley made known its wonderful properties, about the year 1744. These were so con- trary to all former experience, and so repugnant to every established notion of animal life, that the scientific world were amazed ; and while the more cautious among natiu'alists set themselves to verify what it was difficult to believe, there were many who looked upon the al- leged facts as impossible fancies. The discoveries of Trembley were, however, speedily confirmed ; and we are now so familiar with the outlines of the history of the fresh- water polype, and its marvellous reproductive powers, that we can scarcely appreciate the vividness of the sensation felt when it was all novel and strange ; when the lead- ing men of our learned societies were daily experimenting on these poor worms, and transmitting them to one another from distant coun- ti'ies, by careful posts, and as most precious gifts ; and when even ambassadors interested themselves in sending early intelligence of the engrossing theme to their respective courts.

' The name affixed to tlie specific character is that of the person who, so far as I have been able to ascertain the point, added the species to the British Fauna. — Mr Jameson is the present Regius Professor of Natural History in the University of Edinburgh.

+ " Antonius v. Leeuwenhoek, civis Delphensis, peritus vitrorum politor, curiosus, et ad paradoxas opiniones pronus." Haller, Bib. Bot. i. 583. He was born 1632 ; elected F. R. S. .January 1680 ; and died in 1723.

4

Hydra. Z. HYDROIDA. 99

The Hydrae are found in fresh and, perhaps, also in salt waters, but the former species only have been examined with care, and are the objects of the following remarks. They prefer slowly running- or al- most still water, and fasten to the leaves and stalks of submerged plants by their base, which seems to act as a sucker. The body is exceedingly contractile, and hence liable to many changes of form : when contracted it is like a tubercle, a minute top or button, and when extended it becomes a narrow cylinder, being ten or twelve times longer at one time than at another, the tentacula suifering changes in their length and diameter equal to those of the body. " It can lengthen out or shorten its arms, without extending or contracting its body ; and can do the same by the body, without altering the length of its arms : both, however, are usually moved together, at the same time and in the same direction." — The whole creature is apparently homo- geneous, composed of minute pellucid grains cohering by means of a transparent jelly, for even with a high magnifier no defined organiza- tion of vessels and fibres can be detected. On the point opposite the base, and in the centre of the tentacula, we observe an aperture or mouth which leads into a wider cavity excavated as it were in the midst of the jelly,* and from which a narrow canal is continued down to the sucker. When contracted, and also when fully extended, the body appears smooth and even, but " in its middle degree of exten- sion," the sides seem to be minutely crenulated, an efi'ect probably of a wrinkling of the surface, although from this appearance Baker has concluded that the Hydra is annulose, or made up of a numl)er of rings capable of being folded together or evolved, and hence, in some measure, its extraordinary ability of extending and contracting its parts.-j- That this view of the Hydra's structure is erroneous, Trem- bley has proved ;J and the explanation it afforded of the animal's con- tractility was obviously unsatisfactory, for it was never pretended that

Pallas denies this. " Ab alimento recepto cavata, inquam, baud enim Hy- dra corpus naturaliter intestini instar cavum crediderim. Totum solidum et medullare, pro admoto alimento, cerae instar, digitum admittentis, cavari concipio parenchyma et alimentis insinuatis sese circumfundere. Qui alias per longi- tiidinem dissecta Hydra, illico qualibet portione deglutire, et cavo clauso alimen- ta condere posset ? quod tamen observai'e rarum non est." Elench. Zooph. 27, 28. — For a view of the Hydra's stomach see Tremb. Mem. pi. 4, fig. 7, copied by Roget in his Bridgew. Treat, ii. 74, fig. 241.

-|- " The outward coat is white like the arms, and made up of minute annuli or ringlets, that double in the midst, and can, occasionally, be folded close to- gether, in the manner of a paper lanthorn." — Hist, of the Polype, 25.

\ Mem. 27.

100 Z. HYDKOIDA Hydra.

such an anatomy could be detected in the tentacula, which, however, are equally or more contractile. These organs encircle the mouth and radiate in a star-like fashion, but they seem to originate a little under the lip, for the mouth is often protruded Hke a kind of small snout : they are cylindrical, linear or very slightly tapered, hollow and roughened, at short and regular intervals, with whorls of tuber- cles which, under the microscope, foi'ra a very beautiful and interest- ing object ; and I have thought, when viewing them, that every lit- tle tubercle might be a cup or sucker similar to those which garnish the arms of the cuttle-iish.* Trerabley has shewn us that this is a deception, and that there is really no exactness in the comparison. t The tentacula are amazingly extensible, from a line or less to one or, as in H. fusca, to more than eight inches ; and " another extraordi- nary circumstance is, that a polype can extend an arm in any part of its whole length, without doing so throughout, and can swell or les- sen its diameter, either at the root, at the extremity, in the middle, or where it pleases : which occasions a great variety of appearances, making it sometimes terminate with a sharp point, and at other times blnnt, knobbed, and thickest at the end, in the figure of a bob- bin." We naturally enquire how this wonderful extension is made, — by what power a part without muscularity is drawn out until it ex- ceeds by twenty or even by forty times the original length ? The dissections of Trembley have proved beyond any doubt that the body is a hollow cyhnder or bowel, and that the tentacula are tubular and have a free communication with its cavity ;J and in this structure, combined with the loose granular composition of the animal, we find an answer to the question. Water flows, let us say by suction, into the stomach through the oral aperture, whence it is forced by the vis a tergo, or drawn by capillary attraction, into the canals of the tentacula, and its current outvvards is sufficient to push before it the soft yielding material of which they are composed, until at last the resistance of the living parts suffices to arrest the tiny flood, or the

* Pallas has the same suggestion Elench. 26. See also Roget's Bridgew. Treat, i. 182. — Baker says that " two or three pretty long hairs" issue from each of the papilke or tubercles, p. 36 ; and Trembley has figured a short hair issu- ing from some of them, Mem. 62, pi. 5, fig. 3. This appearance of hairs is, I presume, produced by the glutinous secretion from them being drawn out into fine lines and drying on the glass. The tentacula probably adhere to foreign bodies principally by means of a mucous excretion, and being as it were en- grained into the microscopic interstices of the body to which they are applied — Tremb. Mem. 46.

t Mem. 108.

t Ibid. 123—5; and 26-3.

Hybra. Z. HYDROIDA. 101

tube has become too fine in its bore for the admission of water attenu- ated to its smallest possible stream, — how inconceivably slender may indeed be imagined, but there is no thread fine enough to equal it, seeing- that the tentacula of Hydra fusca in tension can be compared to nothing- gi-osser than the scarce visible filament of the gossamer's web.

The Hydra, thoug-h usually found attached, can nevertheless move from place to place, which it does either by gliding- with impercep- tible slowness on the base, or by stretching- out the body and tenta- cula to the utmost, fixing- the latter, and then contracting- the body towards the point of fixture, loosening at the same time its hold with the base ; and by reversing these actions it can retrograde. Its or- dinary position seems to be pendant or nearly horizontal, hanging from some floating weed or leaf, or stretching from its sides. lu a glass of water the creature will crawl up the sides of the vessel to the surface, and hang from it, sometimes with the base, and some- times with the tentacula downwards ; and again it will lay itself along horizontally.* Its locomotion is always very slow, and the disposi- tion of the zoophyte is evidently sedentary ; but the contractions and mutations of the body itself are sufficiently vivacious, while in seiz- ing and mastering its prey it is surprisingly nimble ; seizing a worm, to use the comparison of Baker, " with as much eagerness as a cat catches a mouse." It is dull and does not expand freely in the dark, but enjoys light, and hence undoubtedly the reason why we generally find the Hydra near the surface and in shallow water.

The Hydrae are very voracious, feeding only on living- animals, f but

* " The position in which they appear to take most delight, is that of re- maining suspended from the surface of the v/ater by means of the foot alone : and this they effect in the following manner. When the flat surface of the foot is exposed for a short time to the air, above the surface of the water, it becomes dry, and in this state exerts a repulsive action on the liquid, so that when drag ged below the level of the surface, by the weight of the body, it still remains uncovered, and occupies the bottom of a cup-shaped hollow in the fluid, thereby receiving a degree of buoyancy, sufficient to suspend it at the surface. The principle is the same as that by which a dry needle is supported on water, in the boat-like hollow which is formed by the cohesive force of the liquid, if care be taken to lay the needle down very gently on the surface. If, while the Hydra is floating in this manner, suspended by the extremity of the foot, a drop of water be made to fall upon that part, so as to wet it, this hydrostatic power will be destroyed, and the animal will immediately sink to the bottom." — Roget. Bridgw. Tr. i. 179. This passage is nearly a literal translation fron Trembley's Hist, des Polypes, p. 37-8.

f In confinement however, Trembley found that they might be fed on min- ced fish, beef, mutton, or veal — Mem. 104.

102 Z. HYDROIDA. Hydra.

when necessary they can sustain a fast of many weeks without other loss than what a paler colour may indicate. Small larvae, worms, and entomostracous insects seem to be the favourite food, and to en- trap these they expand the tentacula to the utmost and spread them in every direction, moving them gently in the water to increase their chances, and when a worm, &c. touches any pait of them it is im- mediately seized, cari'ied to the mouth by these flexible and contrac- tile organs, and forced into the stomach. " 'Tis a fine entertainment,'' says Baker, " to behold the dexterity of a polype in the mastering its prey, and observe with what art it evades and overcomes the su- perior strength or agility thereof. Many times by way of experi- ment, I have put a large worm to the very extremity of a single arm, which has instantly fastened on it with its little invisible claspers. Then it has afforded me inexpressible pleasure to see the polype poising and balancing the worm with no less seeming caution and judgment than a skilful angler shows when he perceives a heavy fish at the end of a single hair-line, and fears it should break away. Contracting the arm that holds it, by very slow degrees, he brings it within the reach of his other arms, which eagerly clasping round it, and the danger of losing it being over, all the former caution and gentleness is laid aside, and it is pulled to the polype's mouth with a surprising violence."* Sometimes it happens that two polypes wiU seize upon the same worm, when a struggle for the prey ensues, in which the strongest gains of course the victory ; or each polype begins quietly to swallow his portion, and continues to gulp down his half until the mouths of the pair near and come at length into actual con- tact. The rest which now ensues appears to prove that they are sensible of their untoward position, from which they are frequently liberated by the opportune break of the worm, when each obtains his share, but should the prey prove too tough, woe ! to the unready ! The more resolute dilates the mouth to the requisite extent; and de- liberately swallows his opponent, sometimes partially, so as, however, to compel the discharge of the bait, while at other times the entire polype is engulped ! But a polype is no fitting food to a polype, and his capacity of endurance saves him from this living tomb, for after a time, when the worm is sucked out of him, the sufferer is disgorged with no other loss than his dinner.f This fact is the more remark- able when it is contrasted with the fate which awaits the worms on which they feed. No sooner are these laid hold upon than they evince every symptom of painful suffering, but their violent contortions ore

* Hist, of the Polype, G5. Also Roget's Biidgw. Treat ii. 76 t Trembley, Mem. 112.

Hydka. Z. HYDROIDA. 103

momentary and a certain death suddenly folloivs their capture. How this effect is produced is mere matter of conjecture. Worms, in or- dinary circumstances, are most tenacious of life even \inder severe wounds, and hence one is inclined to suppose that there must l)e something- eminently poisonous in the Hydra's grasp, as it is impos- sible to believe, with Baker, that this soft toothless creature can bite and inject a venom into the wound it gives. " I have sometimes," says Baker, " forced a worm from a polype the instant it has been bitten, (at the expence of breaking off the polype's arms,) and have always observed it to die very soon afterwards, without one single instance of recovery."* To the Entomostraca, however, its touch is not equally fatal, for I have repeatedly seen Cyprides and Daphnise entangled in the tentacula and arrested for some considerable time, escape even from the very lips of the mouth, and swim about after- wards unharmed ; perhaps their shell may protect them from the poisonous excretion — The grosser parts of the food, after some hours' digestion, are again ejected by the mouth ; but, as already mention- ed, the stomach is furnished with what, in one sense, may be called an intestine to which, according to Trembley and Baker, there is an outlet in the centre of the base, and the latter asserts that he has, " several times, seen the dung of the polype in little round pellets discharged at this outlet or anus."f

* Hist, of the Polype, 33 — comp. with 67-8 " That insigiiilicant and inac- tive insect called the fresh water polypus, of all poisonous animals, seems to possess the most powerful and active venom. Small water-worms, which the polypus is only able to attack, are so tenacious of life, that they may be cut to pieces without their seeming to receive any material injury, or to suffer much pain from the incisions. But the poison of the polypus instantly extinguishes every principle of life and motion. What is singular, the mouth or lips of the polypus have no sooner touched this worm than it expires. No wound, how- ever, is to be perceived in the dead animal. By experiments made \\\t\\ the best microscopes, it has been found, that the polypus is neither provided with teeth, nor any other instrument that could pierce the skin." Smellie's Phil, of Nat. History, ii. 462 — The fact that fishes cannot be made to swallow Hydraj, seems to prove the presence of some irritating quality in the latter See Trem- bley, Mem. 137.

f Lib. s. cit. 27. — He adds, — " Much the greater and grosser part of what the polype eats, is most certaiidy thrown out again by the mouth, after lying a proper time to become digested in the stomach -. and, for a good while, I ima- gined there was no other evacuation ; but am now convinced, that the finer part, in small quantity, is carried downwards through the tail, and passed off that way. I believe however there is also another purpose to which this passage serves, and that is, to convey a mucus or slimy matter to the end of the tail, for its more ready adhesion to sticks, stalks, or other bodies."

104 Z. HYDROIDA. Hydra.

But the Hydra is principally celebrated on account of its manner of propagation. It is of course like zoophytes in general, asexual; and every individual possesses the faculty of continuing and multiply- ing its race, principally, however, by the process of subdivision. During the summer season, a small tubercle rises on the surface, which lengthening and enlarging every hour, in a day or two de- velopes in irregular succession, or in successive pairs,* a series of tentacula, and becomes in all respects, excepting size, similar to its parent. It remains attached for some time, and grows and feeds, and contracts and expands after the fashion of this parent, until it is at length thrown off by a sort of sloughing or exfoliation. These buds sprout, in the common species, from every part of the surface of the body, but not from the tentacula; and very often two, three or four young may be seen depending at one time from the sides of the fruit- ful mother, in different stages of gi'owth, every one playing its part independent of the others :

" where some are in the bud,

" some green, and rip'ning some, while others fall."

They are evolved with rapidity in warm weather especially, one no sooner dropping off than another begins to germinate ; " and what is most extraordinary, the young ones themselves often breed others, and those others sometimes push out a third or fourth genera- tion before the first fall off from the original parent." — Trembley found in one experiment that an individual of H. grisea produced forty-five young in two months ; the average number per month in summer was twenty, but as each of these began to produce four or five days after its separation, the whole produce of a month was pro- digious, f

" No sooner is a young one furnished with arms, than it seizes and devours worms with all possible eagerness ; nor is it an unusual thing to behold the young one and the old one struggling for, and gorging different ends of the same worm together. Before the arms come out, and even sometime afterwards, a communication continues between the bodies of the old and young, as appears beyond dispute by the swelling of either when the other is fed. J But a little before the young one separates, when its tail-end begins to look white, trans- parent, and slender, the passage between them, I believe, is closed. And when the young one comes away, there remains not the least

Baker's Hist. 35. f Mem. pour I'Hist- des Polypes, 174 — 5. Also Baker, lib. s. cit. 53 — 4. ^ By some clever dissections, Trembley demonstrated the reality of this com- munication. Mem. 161-2.

Hydra. Z. HYDKOIDA. 105

mark where it had been protruded." — " After a young polype once gets all its arms, it alters indeed in size, but neither appears to shift its skin, or undergo any of the changes most other insects do." *

Instead of buds or little protuberances, the body sometimes push- es forth single tentacula scattered irregularly over it, and these ten- tacula can be metamorphosed into perfect polypes, the base swelling out to become the body, which, again soon shoots out additional ten- tacula to the requisite number ! f

This is a mode of generation which the term viviparous does not correctly embrace, unless we give to that word a signification so ex- tensive as to include all generations which are not oviparous : It is an example of equivocal, or what some foreign physiologists deno- minate, the generation by the individualisation of a tissue previously or already organised, jj — and seems to be the usual way of propaga- tion among the Hydrae during the summer months. But in autumn the Hydra generates internal oviform gemmules which, extruded from the body, lie during the winter in a quiescent state, and are stimulat- ed to evolution not until the return of spring and its genial weather. Few observations have been made on these apparent ova, so that their structure, their source, their manner of escape from the body, and their condition during winter are scarcely known. Trembley de- sci'ibes them as little spherical excrescences, of a white or yellow co- lour, attached to the body by a very short pedicle. He never saw more than three on the same polype. After some time they became separate, and fell to the bottom of the glass of water in which the creatures were kept, where they came to nothing, excepting one only which was presumed to have evolved into a polype, for although his experiment renders this conclusion probable, it was still x'ather an inference than an actual observation, so much so, that Trembley con- tinued to entertain doubts of their nature. Jussieu, it seems, con- ceived that each little excrescence was a vesicle filled with ova of

" Baker, lib. s. cit. 50. t Baker ut cit. 110—11 ■. 121—3.

\ La generation n'est pas pour cela spontanee ; una generation spontanee doit etre la production d'un etre organise de toutes pieces, lorsque des elemens in- organiques se reuniront pour produire un animal, une plante. Cette generation est impossible, et n'a jamais lieu. Une generation equiuoque est celle ou des tis- sus organises prealablement par un etre deja pourvu de vie, sHndividualisent, c'est-a-dire se separent de la masse commune et participent encore, apres cette separation, de I'etat dynamique de la masse, c'est-a-dire de sa vie, mais, a son propre profit. C'est ainsi qu'un tissu produit un Entozoaire. C'est de la vie continuee." — Ch. Morren in Ann. des Sc. Nat. an. 1836, Vol. vi. j). 90. Part. Zool.

106 Z. HYDROIDA. Hvlua.

microscopic minuteness, but there is no foutulation for any such hy- pothesis. *

These are the modes in which the Hydra naturally multiplies its kind, but it can be increased, as already hinted, by artificial sections of the body, in the same manner that a perennial plant can be by slips and shoots. If the body is halved in any direction, each half in a short time grows up a perfect Hydra ; if it is cut into four or eight, or even minced into forty pieces, f each continues alive, and de- velopes a new animal, which is itself capable of being multiplied in the same extraordinary manner. If the section is made lengthways, so as to divide the body into two or more slips "connected merely by the tail, they are speedily resoldered, like some heroes of fairy tale, into one perfect whole ; or if the pieces are kept asunder, each will become a polype, and thus we may have two or several polypes with only one tail between them ; but if the sections be made in the contrary direction — from the tail towards the tentacula — you produce a mon- ster with two or more bodies and one head. If the tentacula, — the organs by which they take their prey, and on which their existence might seem to depend, — are cut away, they are reproduced, and the lopt off parts remain not long without a new body : if only two or three tentacula are embraced in the section, the result is the same ; and a single tentaculum will serve for the evolution of a complete creature. :{: When a piece is cut out of the body the wound speedily heals, and, as if excited by the stimulus of the knife, young polypes sprout from the wound more abundantly, and in preference to un- scarred parts ; when a polype is introduced by the tail into another's body, the two unite and form one individual ; and when a head is lopt

* Trenibley, Mem. 196—7.

f " J'ai ouvert sur ma main iin Polype, je I'ai etendu, et j'ai coupe en tout sens la peau simple qu'il formoit, je I'ai reduit en petits morceaux, je Tai en quelque maniere hache. Ces petits morceaux de peau, tant ceux qui avoient desbras, que ceux qui n'en avoient point, sout devenus des Polypes parfaits." — Tiembley, Mem. 248. Rome de Lisle attempted to lessen the remarkableness and singularity of this fact by supposing that the Hydra was a colony of minute aninialcides held together in a moveable polypidoni, represented by the thin outer cuticle, and of course that this cutting and division only set free a number of in- dependent entire beings. The hypothesis is a bold one, but has nothing in the way of observation to support it. See Blainv, Actinol. p. 56.3.

I From the experiments of Trembley, (Mem. 235,) of a correspondent of Baker's and of Baker himself, it would seem that a tentaculum cannot produce a new body unless a part of the head or body is removed with it (Hist. 19.3-4,) ; but other experimentalists are said to have succeeded when this was not done. I'or the particulars stated in the text, and others equally incredible, the reader may consult the works of Trembley and Baker, passim.

Hydra. Z. HYDROIDA. 107

off it may safely be ingrafted on the body of any other which may

chance to want one. You may slit the animal up, and lay it out flat

like a membrane, with impunity ; nay it may be turned inside out,

so that the stomachal surface shall become the epidermous, and yet

continue to live and enjoy itself. * And the creature even suffers

very little by these apparently cruel operations,

— " scarce seems to feel, or know His wound, — "

for before the lapse of many minutes, the upper half of a cross sec- tion will expand its tentacula and catch prey as usual ; and the two portions of a long-itudinal division will, after an hour or two, take food and retain it. " A polype cut transversely, in three parts, re- quires four or five days in summer, and longer in cold weather, for the middle piece to produce a head and tail, and the tail part to get a body and head, which they both do in pretty much the same time. The head part always appears a perfect polype sooner than the rest." " And what is still more extraordinary, polypes produced in this man- ner grow much lai'ger, and are far more prolific, in the way of their natural increase, than those that were never cut. It is very common when a polype is divided transversely, to see a young- one push out from one or other of the parts, and sometimes from both of them, in a very few hours after the operation has been performed : and par- ticularly from the tail part, two or three are frequently protruded in different places, and at different times, long before that part acquires a new head, and consequently whilst it can take in no fresh nourish- ment to supply them with : and yet the young ones proceeding from it, under these disadvantages, thrive as fast, and seem as vigorous as those produced by perfect and uncut polypes." t

When such things were first announced — when to a little worm the attributes of angelic beings were assigned J — it is not wonderful that

* Trembley had several by him " that have remained turned in this manner ; their inside is become their outside, and theif outside their inside : they eat, they grow, and they multiply, as if they had never been turned." — i'hil. Trans. Abridg. \-iii. 627 ; and his Mem. 253, &c. f Baker, lib. s. cit. 92, 93.

X " Vital in every part, not as frail Man In entrails, heart or head, liver or veins, Cannot but by annihilating die ; Nor in their liquid texture mortal wound Receive, no more than can tlie fluid air, All heart they live, all head, all eye, all ear, — — — — and, as they please, They limb themselves, and colour shajie or size Assume, as likes them best." Millon.

108 Z. HYDROIDA. Hydra.

the vulg-ar disbelieved, albeit credulity may be their besetting sin, when even naturalists, familiar with all the miracles of the insect world, were amazed and wist not what to do. " II faut" — exclaimed Reaumur — " il faut porter la foi humaine plus loin qu'il n'est permis a des hommes eclaires, pour le croire sur le premier temoignage de celui qui le raconte, et assure I'avoir vu. Peut-on se resoudre a croire qu'il y ait dans la nature des aniraaux qu'on multiplie en les hachant, pour ainsi dire, par raorceaux ?" * But this illustrious na- turalist was himself the first to promulgate, and experimentally to verify, the discoveries of Abraham Trembley, which have been fully confirmed by many subsequent inquirers, and are now made so familiar to us by their admission into elementary works and treatises on na- tural theology, that we read of them with little surprise and without incredulousness.

* Hist, des Insectes, vi. pref. 49.

Fig. VI.

FAMILY 11. TUBULARIAD^.

2. CoRYNE,* Gsertner. Character. — Polypes Jixed, single^ naked, cylindrical, 07' claviform hut contractile, the head with scattered Jilifoi'm smooth tentncula •■ mouth 0 ?

1. C. SQUAMATA, body more or less clavate ; the tentacula shorter than the body. Gaertner.-f-

Plate II.

Hydra squamata, Mull. Zool. Dan. prod. 230, no. 2786. Zool. Dan. tab.

iv. fig. 1-3. Fabric. Faun. Groenl. 347 Polyporum species margine

conchee insidentes, Bast. Opusc. Subsec. i. 44, tab. 5, fig. 2, c Tubu-

* Coryne = clava = a club.

■)■ Goertner, Joseph, M. D. a native of Wurtemburg, born in 1 732 ; elected F. R. S. in 1761 ; died in 1791. Having visited England, he made several zoological discoveries on the southern coast, published in the Phil. Trans., and the Spicilegia Zoologica of Pallas. He is celebrated for his work " De Fruc- tibus et Seminibus Plantarum." There is an interesting biographical sketch of him in Thomson's Histonj of the Royal Societt/, p. 46-7.

110 Z. IIYDROIDA. CoRYNE.

laria affinis, Turt. Gmel. iv. 6G8. Turt. Brit. Faun. 210. Stew. Elem. ii.

438. Bosc, Vers. iii. 92. Coryne squamata, Jameson in Wem. Mem. i.

565. Lam. Anim. s. Vert. ii. 62, 2de edit. ii. 73. Bosc, Vers. ii. 279.

Fleming in Edin. Phil. Journ. ii. 87- Flem. Pbil. Zool. ii. 616, tab. 5.

fig. 1. Flem. Brit. Anim. 553. Coldstreamin Edin. New Pbil. Journ. ix.

234. Stark, Elem. ii. 443 La Coryne ecailleuse, Blainv. Actinolog.

471 C. multieornis, Templeton in Mag. Nat. Hist. ix. 419 Hy- dra capitata, Mull. Zool. Dan. prod. 230. Hab. Parasitical on sea weeds, corallines, stones and dead shells, at and within low-water mark. " On the shore of the island of Bur- ra, and on the Holm of Cruster, in Bressay Sound, in Shetland," Jameson. At Abercoru ; and at the Isle of May, i?ei;. /)r i^/em««^. Island of Bute, Dr Coldstream. Maybole, Ayrshire, Rev. George Gray. " Found in great plenty on Fucus vesiculosus at the White House Point, Belfast Lough ; Aug. 1807," J. Templeton, Esq. In Berwick Bay, not uncommon.

Polypes in general gregarious, fixed by a narrow disk, from two to six or eight lines in height ; clavate or cylindrical with a knobbed head, rose-coloured or wliite, smooth, fleshy ; the head or upper part furnished with from 5 to 25 scattered filiform tentacula, which are usually much shorter than the body, and not always of equal lengths. In gravid individuals the oviform gemmules hang from the bases of the tentacula in one or several clusters ; they are of a round or el- liptical figure, rose-coloured with a darker centre, and large in pro- portion to the animal.

Towards the roots of the tentacula we can frequently observe a reddish spot which probably indicates the position of the stomach ; and a dusky line prolonged down the centre of the body appears to show that the latter is hollow, the canal being doubtless intestinal. The tentacula are also tubular, as I infer from their being marked with a similar line : unlike those of the Hydra they are smooth, or merely crenulate, but like them they are capable of being shortened and elongated at will, though to a less extent. The form of the body is also varied at pleasure, but all its motions are slow, and indicate a very inferior degree of irritability. I have never been able to disco- ver a mouth or aperture on the top on the body, but Dr Coldstream says, " after having been kept in small vessels of sea-water for some hours, without renewal of the water, some of the animals protrude the inner surface of the mouth, so as to present a convex disc, with the tentacula ranged round it." — The young are of a fine pink or rose colour : at first they resemble little smooth rounded tubercles, which gradually elongate, and soon acquire one, then two, three or four tentacula, and so on imtil the number of maturity is completed, for these organs are developed in succession.

Hermia. Z HYDROIDA. Ill

The clavate rose-ivd specimens I have generally found between tide marks, and the white ones with a long filiform stalk on dead shells dredged from deeper water. On the latter is undoubtedly founded the " Hydra capitata aiha, pedunculo riigoso longo, cir- ris capitis longitiidine" of MuUer ; while the former answer better to his H. squamata, but although at one time disposed to consider them distinct, I am now satisfied of their identity as species, for they graduate so insensibly into one another as to lose even the character of fixed varieties. I am also led to suspect that the H. brevicornis and viinuticornis of Muller, Zool. Dan. prod. p. 230, will be found to be modifications of this species.

The Hydra Tuba of Sir J. G. Dalyell probably belongs to this genus, and may be distinguished by its tentacula being much longer than the body. It inhabits the Frith of Forth near Edinburghj where its natural abode seems the internal concavity of the upper oyster- shell. It extends " about two inches in whole, with its long white tentacula waving like a beautiful silken pencil in the water. It pro- pagates by an external shapeless bud issuing fi'om the side of the pa- rent, and withdrawing, though very long connected by a ligament, on approaching maturity. In thirteen months a single specimen had eighty-three descendants. Singular and distorted forms appear from the successive and irregular evolution of the buds, during subsistence of the connecting ligament." Edin. New Phil. Journ. xvii. 411 ; xxi. 92. and Rep. Brit. Assoc, an. 1834, p. 599.

3. Hermia,* Johnston. Character. — Polype fixed., slieatUeJ. in a thin horny mem- brane, clavate or branched and suhpliytoidal, the apices of the branches clubbed and furnished laith scattered glandular tentacu- la : mouth 0.

1. H. Glandulosa, irregularly or dichotomously branched ;

* I found the name in Shakspeare ;

" What wicked and dissembling glasse of mine,

" Made me compare with Hermia's sphery eyne." When I defined this genus in the Mag. Zool. and Bot. V. ii. p. 326, I was not aware that the same had been instituted by Sars under the name of Stipula, and by Ehrenberg who called it Syncoryne. The latter designation is in direct oppo- sition to the Linntean axiom — " generic names, derived from others by the ad- dition of a syllable, are disapproved ;" — and Sars' name seems to me even more inadmissible, since it is a descriptive term in Botany. The fancy that the glands which surround the heads were the guardians of the animal, — its " sphery eyne" — suggested the name here adopted.

112 Z. HYDIIOIDA. Hermia.

the tentacula shorter than the enlarged heads of the branches.

Gaertner.

Vignette, No. 12, and Plate IV. Fig 1, 2. Tubularia Corjaia, Turt. Gmel. iv. 668. Turt. Brit. Faun. 210. Stew.

Elem. ii. 438. Bosc. Vers. iii. 91. Hydra ramosa, Fabric. Faun.

Groenl. 348 Coryne Glandulosa, Lam. Anim. s. Vert. ii. 62. 2de

edit. ii. 74. Fleming in Edin. Phil. Journ. ii. 87, and viii. 295. Flem.

Phil. Zool. ii. 616, tab. v. fig. 2. Flem. Brit. Anim. 533. Encyclop.

Method, tab. 69. fig. 15, 16. Johnston in Trans. Newc. Soc. ii. 253 ;

and in Mag. Nat. Hist. v. 631. fig. 110. C. glanduleuse. Blainv. Ac-

tinol. 471. pi. 85, fig. 3, 3 a Coryne, Lister in Phil. Trans, an.

1834, p. 376. pi. 10. fig. 3. Hah. On the under surface of stones between tide-marks ; on old shells, and often parasitical on Tubularia indivisa. Isle of May ; and on the Bell Rock on the coast of Angus, Rev. Dr Fleming. May- bole, Ayrshire, 7?^?'. Geo. Gray. Brighton, J/r Z«>^e>-. Scarborough, Mr Bean. Berwick Bay.

Polypes adherent by a tubular fibre which creeps along the surface of the object on which they grow, seldom an inch in height, irregu- larly branched, the stem filiform, tubular, horny, subpellucid, wrink- led and sometimes ringed at intervals, especially at the origin of the branches, each of which is terminated with an oval or clubshaped head of a reddish colour, and armed v.'ith short scattered tentacula tipt with a globular apex. The ends of the branches are not perfo- rated, but completely covered with a continuation of the horny sheath of the stem. The animal can bend its armed heads at will, or give to any separate tentaculura a distinct motion and direction, but all its movements are very slow and leisured.

When parasitical on Tubularia this zoophyte surrounds the stalks, for the space of an inch or more, with a thick beard-like mossiness composed of entangled corneous fibres, not coarser than a sewing thread, and more irregularly branched than when the polypes have greater freedom to spread. This variety is figured on Plate IV. Fig. 1, 2. The stem is filled with a pulpous medulla, enlarged in the heads and continued up the tentacula, the round tips of which ap- peared to be smooth and areolar under a magnifier, but Mr Lister says they are covered with " short projections like blunt hairs," " and it seems to be by their means that the polypi attach with a touch, or release at will, substances that drift within their reach." Mixed with the tentacula, on some heads, there are a few round and larger bodies of a deep red colour in the centre with a transparent al- buminous envelope : these are supported on a very short stalk, and

are evidently the gemmules by which this .s])ecies is propagated.

3

TuBULARiA. Z. HYDROIDA. 113

On examining a few tubes under the microscope I perceived in one of them, and only in one, a crowd of minute elliptical bodies which were in active motion, running up the tube on one side, and down on the other, but frequently crossing, nor was it uncommon to see one ac- celerate its pace and beat the others in the race. The tube had lost its head, and the moving bodies were evidently, as I think, infusory animalcules which had got admission into it ; — the currents they created are therefore to be distinguished from those observed by Mr Lister, analogous to the circulation in the Tubularia and Sertula- riadae.

4. Tubularia,* Linnaeus. Character. — Polypidom rooted, more or less plant-like, hor- 7iy,Jistular, simple or branched ; no cells — Polypes protruding at the ends of the tubes or branchlets, non-retractile, the head crested with one or two circles oftentacida.

* Tubes undivided. L T. iNDiviSA, tid)es clustered, simple, cylindrical, narrowed and interwoven at the base : head of the polype crested with tivo rows of tentacula. E. Lhwyd. f

Plate IIL Fig. 1, 2. Remarkable Sea-plant, Lhwyd m Phil. Trans, abridg. vi. 7.3, pi. .0, fig. 1.

(pessima.) Adianti aurei minimi facie planta marina, Rail, Syu. 31,

no. 4. Jussieu in Mem. Acad. Roy. des So. 1742, p. 296, tab. 10, fig.

2. Tubular coralline like oaten pipes, Ellis in Phil. Trans, xlviii.

tab. 17, fig. D. Ibid, abridg. x. 453, pi. 10, fig. D. Corall. 31, no.

2. tab. 16, fig. C. Tubularia indivisa, Lin. Syst. 1301. Soland.

Zooph. 31. Berk. Syn. i. 214. Turt. Gmel. iv. 666. Blumenb. Man. 272. Turt. Brit. Faun. 210. Steiu. Elem. ii. 437. Wern. Mem. i. 563. Lam. Anim. s. Vert. ii. 110. 2de edit. ii. 125. Lamour. Cor.

* Formed from tuhulus — a little hollow pipe.

t Edward Lhwyd or Lloyd (as Dillenius spells the name) was born in 1670 and died in July 1709. He was keeper of the Ashmolean Museum, Oxford, and was distinguished among his contemporaries for knowledge in antiquities and natural history. " He is indeed," writes Archdeacon Nicolson, afterwards Bishop of Carlisle, and a very competent judge, " if I may judge of him, the greatest man (at antiquities and natural philosophy together) that I have had the happiness to converse with." Letters to R. Thoreshy, F. R. S. v. i. p. 206. Ray gratefully records his assistance in the Synopsis and Hist. Plantarum ; and Petiver frequently mentions him as his " worthy," " curious," and " generous friend." Of his life and writings the reader wall find an account in Pulteney's Sketches of Botany in England, v. ii. p. 110-116 : and some additional particu- lars in the " Analecta Scotica," especially in the Seco7id Series published at Edinburgh during the present year.

H

114 Z. HYDROIDA. Tubularia.

Flex. 230. Corall. 100. Cuv. Reg. Anim. iii. 299. Bosc, Vers, iii. 89, pi. 28, fig. 3. Fkm. Brit. Anim. 552. Johnston in Trans. Newc. Soc. ii. 252. Dalyell in Edin. New Pbil. Journ. xvii. 411 ; and xxi, 93; and in RejJ. Brit. Assoc, an. 1834, 600. Lister in Pliil. Trans, an. 1834,

366, pi. 8, fig. I Tub. calamaris. Pall. Elench. 81 Tub. gigan-

tea, Lamour. Soland. 17, tab. 68, fig. 5 Tub. gracilis? Harvey in

Proc. Zool. Soc. no. 41, p. 54 La Tubulaire ehalumeau, Blainv.

Actinolog. 470.

Hub. On shells and stones from deep water. Leith shore ; Ork- ney and Shetland Islands, Professor Jameson. Scarborough, Mr Bean. Coast off Dunstanborough Castle, 31r R. Emhleton. Cul- lercoats, Northumberland, 3Ir J. Alder. Berwick Bay.

The tubes are simple or sometimes divided once at the base, where they are twisted and flexuous, fistular, even, continuous or sometimes wrinkled at distant intervals with a few annulations, horn-coloured, from 6 to 12 inches in height, and about a line in diameter. Ellis's comparison of them to " part of an oat-straw, with the joints cut oiF," is very apt. They are filled with a soft almost fluid reddish-pink pulp in organic connection with the Polypes, which project from the open ends of the tubes, and are not retractile within them. The body, or naked portion, of the polype forms a globular knob of a scarlet colour, produced above into a sort of proboscis encircled with a series of nu- merous short tentacula of the same colour. Around the base of this body there is another circle of much long-er tentacula from 30 to 40 in number ; and between their insertion and the body clusters of ovi- form g-emmules are produced at certain seasons. The neck of the polype is greatly constricted ; and we find that the recent tube is marked with several longitudinal pale lines, placed at equal distances, and which are evidently caused by some structure of the interior pulp, for when empty the tubes exhibit no such appearance. What is their relation to the currents observed by Mr Lister? — As the animal be- comes weak when kept in a basin of sea-water, the head drops off, like a flower from its stalk ; and if it is immersed, even when most vivacious, in fresh-water, the pulp is expelled from the tubes until these are almost emptied. If this is efl"ected by a contraction of the tube (and the phenomenon is not otherwise easily explained), does not this imply a degree of irritability in the polypidom inconsistent with the theory of its extravascular character ?

I can find no characters either in the description or fig-ure of Tub. gigantea which warrant its separation as a distinct species. The character of Lamouroux is : " T. tubulis rectis, simplicissimis, ad basim attenuatis, gradatim dilatatis, deinde tequali crassitie, laevibus nitidisque." — Neither do I find in Mr Harvey's description of his

TuBULARiA. Z. HYDROIDA. 115

Tub. gracilis any essential specific character : the differences he points out between it and T. indivisa seem to depend on the pecuHar locali- ty of the former, viz. on chains or wood exposed to a rapid current.

2. T. Larynx, tubes clustered, slender, cylindrical, ringed at regular intervals : polypes tvith a double series of tentacula. Plate III. Fig-. 3, and Plate IV. Fig. 3-5.

Var. a. The tubes simple or undivided. Plate III. Fig. 3. Fucus Dealensis fistulosus, laryngae similis, Raii, Syn. i. 39, no. 8. Petiv. Oper. iii. 39, no. 406. Ellis in Phil. Trans, abridg. x. 453, pi. 10, fig. c, and xi. pi. 5, fig. 3, young Tubulous Coralline wrinkled like the windpipe, El- lis, Corall. 30, no. 1. tab. 16, fig. h. Corallina tubularia laryngi similis, Bast. Opusc. Subs. 41, tab- 2, fig. 3-4 ; and tab. 3, fig. 2-4 Tubu- laria muscoides. Pall. Elench. 82. Berk. Syn. i. 214. Turt. Gmel. iv. 667. Turt. Brit. Faun. 210. Stetv. Elem. ii. 438. Bosc, Vers, iii. 90. Flem. Brit.

Anim. 552. Tub. Larynx, Soland. Zooph. 31. Lavi. Anim. s. Vert.

ii- 110. Hogg's Stock. 34. — La Tub. muscoide, Blainv. Actinolog. 470.

Var. b. The tubes sparingly and irregidarhj branched. Plate IV. Fig. 3,

4, 5, and Plate V. fig. 3, 4. Tubularia muscoides ? Lin. Syst. 1302.

Corall. 101. Fistularia muscoides ? Mull. Zool. Dan. prod. 254, no.

3068 Fistulana muscoides ? Fabric. Faun. Groenl. 442.

Hab. On shells, corallines, Sec. beyond low-water mark, (a.) " Found about Deal by the Reverend Mr Hugh Jones* and Mr James Cuninghame f " Petiver. " Found in great plenty in the sea, near the opening- of the Thames, adhering to other marine bodies, and often to the bottoms of ships," Ellis. Stockton-on-Tees, J. Hogg, Esq. Scarborough, Mr Bean. — (b.) Berwick Bay, parasitical on Tu- bularia indivisa and ramea.

Polype-tubes, in var. a, clustered, about 2 inches in height, un- divided and fiHform, more or less entwined at the base, of a thin pel- lucid pale corneous texture, wrinkled and annulatedat intervals, whence

* " A very curious person in all parts of Natural History, particularly in Fos- sils, some of whicli he hath sent me from Maryland, \\Tth several volumes of Plants very finely preserved ; with divers Insects and Shells. From this oblig- ing gentleman, I am promised frequent remittances of whatever those parts af- ford, as well Animals and Fossils as Vegetables." — Petiver.

f Cuninghame was a Surgeon, probably in the East India Company's service, and had visited those places which lie in the course of its trade, whence he brought numerous plants, &c. to enrich the museum of Petiver. The latter styles him " that industrious promoter of Natural Philosophy, and my very ingenious friend ;" — " my very worthy friend ;" — " my hearty friend ;" and the 20th plate of Petiver's English Plants is gratefidly dedicated to the memorij of this " his curious friend," to whom he says he was " beyond expression obliged." Cuninghame is the author of a paper on the plants of the island of Ascension in Phil. Trans, no. 255 ; and seems to have deserved the praises which his con- temporaries bestowed.

110 Z. HYDROIDA. Tubularia.

each tube assumes somewhat the appearance of the wind-pipe of a small bird. In var. b, the tubes are distinguished by being- slightly branched, the branches coming- off irregularly and at vai'ious angles. They rise to about 3 inches in height, and are smooth in a fresh state, but when dried exhibit the annulations distinctly, especially at the origin of the branches. The naked body of the polypes is rose-red, more or less deeply tinted, while the tentacula are milk-white, or sometimes faintly tinged with red. Of these there are two series : one round the oral aperture composed of short threads usually held in an erect position ; the other forms a circle round the most bulging part of the body, and consists of more than 20 long filaments which spread like rays from a centre, or droop elegantly, being usually held still, or allowed listlessly to follow the undulations of the water. When the polypes are all displayed, they afford a very interesting and pretty spectacle, equalled by no other species I have seen, the crimson heads contrasting finely with their white polypidoms, es- pecially when loaded with the gemmules which pullulate from the inner side of the bases of the inferior tentacula. When few in num- ber and immature these gemmules are sessile and separate, but in their progress to evolution they form grape-like clusters : each sepa- rate gemmule is of a roundish or oval shape, consisting of a white al- buminous coat with a dark red cylindrical centre. — Plate IV. Fig. 5. According to Agardh and Lamouroux the Tubularia muscoides of Linnaeus is distinct from the T. Larynx of Ellis and Solander, but his specific character — " T. cuhnis subdicJiotomis, totis annuloso-ru- gosis," — answers sufficiently to our b in a dried state to induce me to quote it as a synonyme, the more so as Linnaeus refers to Ellis's fi- gure for a representation of what he intended. The Tubularia po- lyceps of Sir J. G. Dalyell in Rep. Brit. Assoc, an. 1834, p 601, and Edin. New. Phil. Journ. xxi. 93, appears to be referable to the same variety. From the observations of this ingenious naturalist we must infer that the mimher o\ tentacula is an uncertain character : he says, " a specimen had originally 21 tentacula, but only 16 were renovated with the second head ; and with the seventh they had diminished to six.

* * Tubes ramous. (Eudendrium, Ehrenberg.) t3. T. RAMOSA, tube single, irregularly branched, the branches erecto-patent, ringed and rather narrower at their origins : poly- pes with a single series oj" tentacula. J. Ellis.

Small ramified tubular coralline, Ellis, Corall. 31, No. 3, tab. 16, fig. a ; and tab. 17, fig. a, A Tubularia trichoides, Pall. Elencb. 84. T.

TuBULARiA. Z. HYDROIDA. 117

ramosa, ZiK. Syst. 1302. Soland. Zooph. 32. Berk. Syn. i. 214. Turt. Gmel. iv. 6G6. Turt. Brit. Faun. 210. Stew. Elem. ii. 437. Wern. Mem. i. 56S. Lam. Anim. s. Vert. ii. 110. 2de edit. ii. 12G. Bosc, Vers, iii. 89. Lamonr. Corall. Trans. 101. Flem. Brit. Anim. 552. Hogg's Stock. 34. Stark, Elem. ii. 441, pi. 8, fig. 15. Templeton in

Mag. Nat. Hist. ix. 466 Fistiilaria ramosa. Mull. Zool. Dan. prod.

254, no. 3067 Fistulaiui ramosa. Fabric. Faun. Groenl. 441 — Tu-

bulaire rameuse et trichoide, Blainv. Actinolog. 470, pi. 30, fig. 3, 3 a, copied from Ellis. ffab. On oysters and other marine productions. " At Whitstable on the Kentish shore ;" and " at Emsvvorth, on the borders of Sussex," £^/lis. " Leith shore, found by the late Mr Mackay," Jameson. Very common on stones, muscle and oyster shells near Stockton-on- Tees, J. Hogg, Esq. " Found on the shore of Dublin Bay," Tem- pleton.

Though said to be common, I am but imperfectly acquainted with this species, which it must be difficult to distinguish from the branch- ed variety of the preceding- except in a living- state, when the polypes afford a certain means of discrimination in the arrangement of their tentacula. In size and texture the two species seem to be nearly alike. Ellis says, " I have often met with specimens of this coral- line that have been regularly branched in a doubly pinnated form ; and when I was at Emsvvorth, on the borders of Sussex, I found a spe- cimen of this Tubularia, with its ovaries placed in a circle round the lower part of its heads." I have had small and imperfect specimens of Thoa halecina sent me as T. ramosa ; nor is it impossible to mis- take the variety of Hermia glandulosa which infests Tubularia indi- visa for it. Lamouroux and Blainville make of Ellis' figure in Plate XVI. their Tub. trichoides, and they restrict the name ramosa to that figured in Plate XVII., but Ellis himself knew no difference, nor am I aware on what grounds these authors place the distinctions between them.

4. T. RAMEA, arborescent, the stem and branches formed of agglutinated fUform tubes irregularly branched : polypes with a single series of tentacula.

Plate V. Fig. 1, 2.

Tubularia ramea. Pall. Elench. 83. Bosc, Vers, iii. 90. T. ramosa,

Johnston in Trans. Newc Soc ii. 253, pi. 10 Fistulana ramosa?

Fabric. Faun. Groenl. 441 Thoa Savignii? Lamour. Corall. 93,

pi. 6, fig. 2, male. Hub. On old shells and on stones from deep water. Shetland and Leith shore, Dr Coldstream. Frequent on the coasts of Northum- berland and Berwickshire.

118 Z. HYDROIDA. Tubularia.

This coralline so perfectly resembles a tree in miniature, deprived of its leaves, that persons unacqiiainted with the nature of zoophytes cannot be persuaded that it is not of a vegetable nature. It is from 3 to 6 inches high, rooted by a densely interwoven mass of tubular fibres, which by their cohesion and intertwining form the stem, which is sometimes as thick as the little finger. This is irregularly divided into many compound branches, formed like the stalk itself, but the ultimate branches consist of a single short tube, ringed at the base, and terminated by the non-retractile polypes. The separate tubes are filiform, not thicker than ordinary thread, of earthy brown colour, horny, wrinkled at intervals. The polypes placed at the extremities of the branches are of a reddish colour and appear indolent in dispo- sition, contracting slowly under external irritations : they have about twenty whitish tentacula arranged in one row round a broad oral disk.

It is possible this may be a state of T. ramosa, but its arborescent character and the complexness of its structure are so remarkable that I have willingly followed the example of Pallas, who has given a description of the species in his usual accurate and expressive style. I find it noticed by no other author, unless perhaps by Otho Fabri- cius, but his description is not sufficiently explicit to remove all doubts of the correctness of his synonyme. The Sertolara racemosa of Cavolini, Polip. Mar. p. J 60, tav. 6, fig. 1, is a nearly alhed species.

The Tubularia flabelliformis of Adams in Lin. Trans, v. 12. {Turt. Gmel. iv. 669. Turt. Brit. Faun. 211. Stew. Elem ii.438.) is a minute parasitical alga of the family Diatomacese.

Fig. 13.

FAMILY III. SERTULARIADiE.

5. Thoa,* Lamouroux. Character. — Polypidoms rooted, arbuscidar : the stem com- posed of aggregated suhparallel capillary tubes ; the branches al- ternate, spreading bifariously : cells tubular, indistinct, alter- nate : ovarian-vesicles irregularly scattered. — Polypes hydraform, scarcely retractile loithin their cells.

1. T. HALECiNA, vesicles oval, the aperture shortly tubuloiis subterminal. Mr. Newton. -f-

Plate VL

* From fleof, sharj) ; or more probably a mispelling of Thoe — one of the Nereids.

f Mr James Newton, a good practical botanist, contemporary with Ray, to whom he sent many contributions for the Synop. Stirp. Brit., and the Hist. Plantarum. He died before the publication of the 3d edition of the Synopsis in 1724, but Dillenius acknowledges his obligations, and introduced several species into our Flora, for the first time, on Newton's authority. I am not aware

120 Z. HYDROIDA. Thoa.

Coralliiia scniposa pennata, cauliculis crassiusculis rigidis, Eaii, Sjii. i. 36,

no. 15 Herring-bone Coralline, Ellis in Phil. Trans, abridg. x. 454.

pi. 10. fig. E, F, G. Coral. 17, no. 15, pi. 10. Phil. Trans, xlviii, 506,

pi. 17, fig. f, E Sertularia halecina, Lin. Syst. 1308. Pall, Elench.

113. Mull. Zool. Dan. prod. 255. Fabr. Faun. Groenl. 443. Ellis and Soland. Zooph. 46. Berk. Syn. i. 217. Turt. Gmel. iv. 678. Turt. Brit. Faun, 213. Wern. Mem. i. 564. Stew. Elem. ii. 442. Bosc, Vers,iii. 109. Lam. Anim. s. vert. ii. 1 1 9. 2de edit. ii. 1 46. Hogg's Stockton, 32. Flem. Brit. Anim. 542. Johnston in Trans. Newc. Soc. ii. 259, pi. 12, fig. 2.

Thoa halecina, Lamour. Cor. Flex. 211. Corallina, 93. Templeton

in Mag. Nat. Hist. ix. 468 La Thoa halecine, Blainv. Actinol. 488,

pi. 84, fig. 4, 4 a. Hah. On old shells and stones in deep water, common. Common on oyster shells in the Frith of Forth, Prof. Jameson. Vicinity of Stockton-on-Tees, J. Hogg, Esq. Found on the shore of Belfast Lough, Mr Templeton. Cork Harbour, J. V. Thompson. Coasts of N. Durham aud Berwickshire.

Polypidom from 4 to 6 inches high, fixed by numerous fibres " ir- regularly matted together like apiece of sponge," of an earthy-brown colour, stiff, brittle when dry, irregularly branched, the stem and prin- cipal branches composite, tapered upwards, pinnate ; the pinnae alter- nate, patent. Cells alternate, tubular, bi-articulate, the aperture even. Vesicles unilateral, scattered, of an oval shape " with a tube arising from the pedicle, and passing up on one side to a little above

the top of each," Ellis Young specimens are often partially

coloured a bright yellow, dependent apparently on the colour of the in- terior pulp. When the specimen is recent and clean the cells are seen to be divided by one or two wrinkles or joints, but in general they are obscurely marked.

2. T. Beanii, vesicles calceoliform, the aperture suhcentral^

shortly tuhulous. Mr William Bean.*

Plate VII. Fig. 1, 2. Hah. " Near Scarborough, in deep water, very rare," Mr Bean. Polypidom 1 1 inch high, irregularly branched, the branches alternate, spreading, the principal composed of many parallel tubes, the ulti- mate of a single tube, with a joint between each cell, which is small,

that any genus of plants has been dedicated to his memory, — an honour of which he seems not unworthy. He must not be confounded with another James New- ton, author of a " Compleat Herbal," Lond. 1752.

"■ Mr B. of Scarborough, well known to naturalists generally by his numerous discoveries in British Zoology, recent and fossil. To some of his new species the trivial name fabalis has been applied, but the justice of such a conceit or puzzle is questionable, since it veils the discoverer's name from those who are not good guessers.

SfiRTULARiA. Z. HYDllOIDA. 121

articulated, cylindrical or somewhat dilated at the aperture. Vesicles mimerous, scattered or imperfectly clustered, large and shaped some- what like the flower of a Calceolaria, with a short tubulous aperture in the middle of its concavity, which is on the superior and inner as- pect.

I have named this curious and very interesting species after its discoverer, to whose kindness I am indebted for the specimen that fur- nished our figure and description. In habit and structure it closely resembles Th. halecina, from which it is, however, at once distin- guished by its remarkable ovaries.

3. T. MURiCATA, vesicles roundish or ovate, echinated. Dr David Skene.

Plate VII. Fig. 3, 4. Sertularia muricata, Ellis and Soland. Zoopb. 59, pi. 7, fig. 3, 4. Turt. Gmel. iv. 681. Turt. Brit. Faun. 215. Stew. Elem. ii. 445. Jame- son in Wem- Mem. i. 564. Flem. Brit. Anim. 543. Hogg's Stockton,

34. JBosc, Vers, iii. 115 Laomedea muricata, Lamoiir. Cor. Flex-

209. Corallina, 92 La Sertulaire muriquee, Blainv. Aotinol. 480.

La Campaniilaire muriquee, Ibid. 473. Hah. On old shells in deep water. The sea at Aberdeen, Skene. Frith of Forth, Jameson. Seaton, J. Hogg. Near Scarboi'ough, TV. Bean.

Polypidom from 2 to 4 inches high, rooted by a fibrous entangled mass, irregularly bi'anched, stout and rigid, yellowish-brown ; the stem and branches composed of capillary tortuous tubes closely ag- glutinated, but the extremities of some of them become free and ap- pear hke simple fibres ; branches erecto-patent, slightly tapered at the point. Cells visible only on the simple fibres, small, alternate, separated by an oblique joint, sessile, campanulate, with an entire even aperture. Vesicles very numerous and often crowded, shortly stalked, roundish or ovate, somewhat compressed, and rough with prickles arranged in lines on elevated striae : when filled with ova the centre is of a deep chesnut-brown colour.

May not the obscure Sertularia echinata of Linnaeus be re- ferable to this species ?

6. Sertularia,* Linnaeus. Character. Polypidoms rooted, plant like, variously branch- ed, the divisions or branches formed of a sinr/le tube divided at regular intervals by imperfect septa : cells paired or arranged in

* From sertula, the diniiruitive of serta, a garland.

122 Z. HYDROIDA. Sektularia.

tuw opposite rotos, sessile, distinct and separated by a joint from the stem, short icith everted apertures : vesicles scattered. — Po- lypes hydraform.

* Cells distinctly alternate. 1. S. PoLYZONiAS, erect, subjlexuous ; cells ovate, with a wide somewhat uneven aperture ; vesicles obovate, wririkled across^ the orifice contracted and plain. Mr Newton, Plate VIII. Fig. 1, 2, 3. Corallina minus ramosa, alterna vice denticiilata, Raii, Syn. 35, no. 13,

tab. 2, fig. 4, male Great Tooth Coralline, Ellis, Coral. 5, no. 3,

pi. 2, fig. a, A. and pi. 38, fig. 1, A. Sertularia polyzonias, Lin.

Syst. 1312. Ellis and Soland. Zooph. 37. Berk. Syn. i. 219. Turt. Gmel. iv. 683. Blumenb. Man. 273. Turt. Brit. Faun. 216. Wern. Mem. i. 564. Stew. Elem. ii. 447. Lam. Anim. s. Vert. ii. 117. 2de edit, ii 142. Lamour. Cor. Flex. 190. Corallina, 83. Risso, L'Europ. merid. v. 130. Bosc, Vers, iii. 119. Hogg's Stockton, 31. Flejn. Brit. Anim. 542. Johnston in Trans. Newc. Soc. ii. 256. Templeton

in Mag. Nat. Hist ix. 468 S. ericoides, Pall. Elench. 127 Ser-

tolara polizonia, Cavol. Polip. Mar. 224, tav. 8, fig. 12-14 La Ser-

tulaire zonee, Blainv. Actinolog. 480. Hah. On shells and other corallines, in deep water. Near Queen- borough in the island of Sheppey, Ellis. Leith shore, Jameson. Coast of Ayrshire, Mr P. W. Maclagan. On the shore of Belfast Lough, Templeton. Cork Harbour, J. V. Thompson. Scarborough, Mr Bean. Coasts of N. Durham and Berwickshire. — (/3.) Corn- wall, Pallas. Isle of Wight, Ellis. Berwickshire.

Polypidoms affixed by a creeping tubular fibre, from 1 to 2 inches high, of a yellowish horn-colour, filiform and slender, scarcely zig- zag, simple or sparingly branched in general, but specimens occasion- ally occur which are bifariously pinnated ; the pinnae alternate, erec- to-patent. Cells rather distant with an oblique joint in the stem above the origin of each of them, urceolate, smooth, the aperture wide and obsoletely tridentate. Polypes white or sometimes bright-yel- low, with numerous tentacula. Vesicles large, sessile, ovate with a short tiibulous apex, smooth or transversely wrinkled on the upper half.

Pallas describes a variety (/3) worthy of notice, not unfrequent on the coast of Cornwall, 3 inches and upwards in height, with a compound stem, and branched in a pinnate manner similar to Thoa halecina, which this variety indeed very closely resembles. Ellis mentions that he had received specimens of the same from the Isle of Wight ; and I have found it on the coast of Berwickshire. In the col- lection of my friend Dr Coldstream there are specimens also, from

Sertularia. Z. HYDROIUA. 123

the Cape of Good Hope, of a still greater size and more robust and shrubby habit, with numerous and compound branches, — evidencing- the genial intluence of climate on the growth and appearance of these corallines.

2. S. Ellisii, climbiny^ Jlexuous ; the cells urceolate, bulged at the hase^ with a ^-toothed rim : vesicles with the opening 4- toothed. Ellis.

Ellis, Corall. (j, pi. 2, fig. h, B. Sertularia Ellisii, M. Edwards in Lam. Anim. s. Vert. ii. 142, 2de edit.

Hah. Parasitical on other corallines.

Under the " Great-tooth Coralline" Ellis describes this shortly : " The other species, which is the climbing one, is more branched, the denticles are placed more asunder, and their mouths are wider : The vesicles of both species are wrinkled." It has been always con- sidered a variety of the preceding until separated from it by Milne- Edwards on what appear to be sufficient characters of distinction. I have seen no specimen.

3. S. Templetoni, ^^ stems simple ; cells short and narroio.*^ Mr Templeton.*

Sertularia Temijletoni, Fleming in Edin. Phil. Journ. ii. 88. Flem. Brit.

Anim. 543 — La S. de Templeton, iJ/flin;;. Actinolog. 480. Lam. Anim.

s. Vert. ii. 152, 2d edit.

Hab. " Loch of Belfast, Mr Templeton," Fleming.

" Height about an inch ; slightly branched ; cells narrow, tubular,

produced ; the vesicles oval, lengthened, narrow at the base, covered

towards the summit with lanceolate spines. This species is of a

more delicate texture than the preceding, (Thoa muricata), the ve- sicles are of a different shape, and the stem is simple. It was given to me by an accomplished naturalist, the late Mr Templeton of Orange Grove, Belfast. It adheres apparently to a gramineous leaf, proba- bly of a zostera, and therefore may be considered an inhabitant of shal- low water." Fleming.

4. S. KUGOSA, cells ovate, twinkled transversely, the mouth nar- row with 3 or 4 small teeth on the rim. J. Ellis.

Pirate VIII. Fig. 4, 5, 6.

Snail-trefoil Coralline, EUis, Corall. 26, no. 23, tab, 15, fig. a, A

Sertularia rugosa, Lin. Syst. L308. Pall. Elench. 126. Ellis and Soland.

* John Templeton, Esq. bom in Belfast in 1 766, where he died, I believe, in 1827. For an interesting memok see the Mag. Nat. Hist. v. i. p. 403, and v. ii. p. 305.

124 Z. HYDROIDA. Sektularia.

Zooph. 52. BeTk. Syn. i. 216. Fahr. Faun. Groenl. 443. Turt. Gmel.

iv. 678. Wem. Mem. i. 364. Tar^ Brit. Faun. 213. Stew.Eiem.n.

442. Lam. Anim. s. vert. ii. 121. 2d edit. ii. 149. Bosc, Vers, iii. 108.

Flem. Brit. Anim. 542. Hogg's Stockton, -32. Johnston in Trans. Newc

Soc ii. 257, pi. 11, fig. 3 Clytia rugosa, Lamour. Cor. Flex. 204.

Corallina, 89. Templeton in Mag. Nat. Hist, ix 466 La Campanu-

laire rugueux, Blainv. Actinol. 473. Hab. Parasitical on Flustrae, Sponges and Fuci at low water-mark, common. Brighthelrastone, Ellis- Near Hai'tlepool, common, Mr Hogg. Leith shore, Jameson. Shores of N. Durham and Berwick- shire.

A small species not exceeding an inch in height, and well distin- guished by its strongly wrinkled cells which resemble a barrel in miniature. Polypidoms gregarious, the shoots united by a radical branching fibre, erect or creeping, obliquely twisted or ringed between the cells, simple or sparingly branched, the branches irregular, pa- tent. Cells crowded, alternate, subsessile, ovate, coarsely wrinkled, especially when dried, contracted at the orifice which is obsoletely tridentate. The ovarian vesicles are sparingly evolved, and differ from the cells only in being a little larger, and in having three teeth in the opening at the top of each. As a parasite it does not confine itself to Flustra foliacea^ as Pallas would have us to believe, but in- fests the roots and stems of many sea- weeds.

* * Cells in pairs, opposite or semialternate. 5. S. ROSACEA, cells opposite, tubulous, the upper half free and divergent, the aperture entire, truncate ; vesicles croicned with spines. Ellis.

Plate IX. Fig. 1, 2. Lily or Pomegranate-flowering Coralline, Ellis, Corall. 8, no. 7, pi. 4, fig.

a, A. Phil. Trans, abridg. x. 492, pi. 12, fig. 5, s — H Sertularia

rosacea, Lin. Syst. 1300. Ellis and Soland. Zooph. 39. Berk. Syn. i. 215. Turt. Gmel. iv. 676. Turt. Brit. Faun. 212. Wern. Mem. i. 564. Stew. Elem. ii. 440. Lam. Anim. s. Vert. ii. 119. Bosc, Vers, iii. 105. Hogg's Stockton, 32. Johnston in Trans Newc. Soc. ii. 258.

Templeton loc. cit. 468 Sert. nigellastrum. Pall Elench. 129..

Sert. abietina ? Fabric. Faun. Grcenl. 442. — Dynamena rosacea, La-

mour. Cor. Flex. 175. Corallina, 79. Flem. Brit. ;Anim. 544. La

Dynamene rosacee, Blainv. Actinol. 484. Hah. Frequent on Corallines, and occasionally on old shells, from deep water. At Brighthelmstone adhering to oyster-shells, Ellis. Scarborough, Mr Bean. A rare species near Hartlepool, Hogg. Coast at Dunstanborough Castle, Mr R, Embleton. Leith shore, Jameson. Shore of Belfast Lough, Templeton. Coast of Berwick- shire and N. Durham.

3

Sertularia.

Z. HYDllOIDA.

125

Polypidom from one to two inches in height, attached by a creep- ing tortuous tubular fibre, very slender and delicate, of a white or pale horn colour, pellucid, variously branched, the branches bifarious, alternate, patent, similar to the stem. Cells opposite, with a joint between each pair, rather long, tubular, the upper half suddenly di- vergent with an oblique entire aperture. Ellis compares the vesicles to a " Lily or Pomegranate flower just opening," but Pallas asserts that the comparisons, as well as the figures of them in Ellis's work, are inaccurate, — a criticism the truth of which Ellis denies in his sub- sequent volume on zoophytes. They appear in fact to vary some- what according to their age, and also from the manner in which they have been dried. They are large and pear-shaped, subsessile, pucker- ed at the top where they are crowned with several spines ;

Fig. 14.

and though scattered over the polypidom, they appear to be produced from one side only, and are often arranged in close rows along the branches. — Our figure is the exact portrait of a beautiful specimen in the collection of Dr Coldstream ; and I have a similar one from Mr Bean, but in general the species is very small and sparingly branched.

6. S. I^VMiLAy cells opposite, approximated, shortly tubular, the top everted with an oblique somewhat mucronated aperture ; vesi- cles ovate. Doody,*

Plate IX. Fig. 3, 4.

" Doody, Samuel, an apothecary in London, contemporary with Ray, Peti- ver and Sloane, admitted F. R. S. in 1695. He was chosen superintendant and demonstrator of the garden at Chelsea, an office which he held for some years before his death, which took place in 1706- Petiver characterises him as an " in- defatigable botanist," and "memorable naturalist." Jussieu speaks of him as " inter Pharmacopoeos Londinenses sui temporis Coryphaeus." Pulteney styles him, " the Dillenius of his time ;"and Brown has crowniedhis praise by bestow- ing his name on a genus of New Holland plants. " In memoriam dixi Samuelis Doody, Pharmacopoei Londinensis, qui primus fere in Auglia plantas cryptoga-

126 Z. HYDROIDA. Sertularia.

Coralliiia pumila repens, minus ramosa, Rail, Syn. i. 37, no- 19 C-

pumila erecta, lamosior, Ibid. 37, no- 20. pi. 2, fig. 1. Muscus ma-

rinus lendigenosus minimus arenacei coloris, Morris. Plant, hist, iii, 650,

tab. 9, fig. 2 Reaumur in Mem- de I'Acad. Roy. des Sc. an. 1711,

394, pi- 11, fig. 4, M Sea-oak Coralline, £Z/js, CoraU. 9, no. 8, pi.

5, fig a, A- Phil- Trans, xlviii- 632, pi. 23, no. 6. Phil. Trans. Ivii. 437, pi. 19, fig. 11. Phil. Tians. abridg. x, 493, pi. 12, fig. 6, F Sertu- laria pumila, Lin. Syst. 1306. Pall. Elench. 1-30. Ellis and Soland. Zooph. 40- Berk. Syn. i. 213. Turt. Gmel. iv. 676. Wern. Mem. i. 564. Turt. Brit. Faun. 212. Stew. Elem. ii. 441, pi. 12, fig. 10, 11, copied from Ellis. Lam. Anim. s. Vert. ii. 119. 2de edit, ii, 145. Bosc, Vers, iii- 105. Hogg's Stockton, 32. Stark, Elem. ii. 440, pi. 8, fig. 14. from Ellis. Johnston in Trans. Newc. Soc. ii. 259. Lister in

Phil. Trans, an. 1834, 371, pi. 8, fig. 3. Templeton, lib. cit- 468

Sertolara pumila, Cavoh Pol- mar. 216, tav. 8, fig. 8-10 Dynamena

pumila, Lamoiir. Cor. Flex. 179. Corallina, 79. Flem. Brit. Anim. 544.

La D. naine, Blainv. Actinol. 484.

Hah. Near low-water mark common, parasitical on various Fuel, particularly F, vesiculosus and serratus- Also on oyster shells.

The polypiferous shoots oi'iginate from a slender tubular thread which creeps along- the surface of the fucus, and connects them all together. The shoots are very numerous, often covering a considerable space of the sea-weed, seldom more than half an inch in height, of a dusky horn colour, and thickish texture, sparingly branched, filiform, flattish, serrated with the cells, which are divided in paii's by a dissepiment or joint. The polypes have 14 tentacula, and when the animal displays them, it at the same time extrudes the body far beyond the rim of the cell. The vesicles are copiously produced during the summer months, and are irregularly distributed over the branches; they are sub- sessile, ovate with a short tubulous rim, smooth, or sometimes wrink- led circularly : in the centre a placentular column is at seasons obvi- ous, and in June 1 have found them filled with innumerable pellucid granules floating in an amniotic liquor.

" This species, and probably many others, in some particular states of the atmosphere, gives out a phosphoric light in the dark. If a leaf of the above Fucus (serratus,) with the Sertularia upon it, receive a smart stroke with a stick in the dark, the whole coralline is most beautifully illuminated, every denticle seeming to be on fire." Steivart,

" While thus with pleasing wonder you inspect Treasures the vulgar in their scorn reject, See as they float along th' entangled weeds Slowly approach, upborne on bladdery beads j

micas investigavit." Prod. Flor. Nov. HoU. p- 7 — See also Pulteney's Sketches, V. ii. p. 107-9.

Sertularia. Z. HYDROIDA. 127

Wait till they land, and you shall then behold The fiery sparks those tangled fronds infold, Myriads of living points ; th' unaided eye Can but the fire, and not the form descry." — Crabhe.

7. S. EvANSii, " has op])osite hranchesy and short denticles placed opposite to each other ; the ovaries are lobated, and arise from opposite branches, which proceed from the creeping adher^ ing tube." Mr John Evans.*

Sertularia Evansii, Ellis and Soland. Zooph. 38. Turt. Gmel. iv, 681. Bosc, Vers, iii, 115. Lam. Anim. s. Vert. 2de edit, ii, 154. Turt. Brit.

Faun. 215. Stew. Elem. ii, 445 Dynaniena Evansii, Lamour. Cor.

Flex. 177. Corallina, 78. Flem. Brit Anim. 543 La D. d'Evan,

Blahiv. lib. cit. 484. Hab. " Among- some sea productions brought from Yarmouth, in Norfolk, in the year 1767/' Ellis.

" This coraUine is about tvi^o inches high, very slender, and of a bright yellow colour. It creeps on fucus's. The ovaries differ from all the rest of the genus : they are lobated, and the lobes are placed opposite to one another : these appear to be full of spawn, of a deep orange colour, which is sent forth from holes at the end of the lobes." Ellis.

8. S. PiNNATA, cells opposite, tubular, the upper -part free and divergent, toith an even patulous aperture ; vesicles obconical, tri- tuberculate on the top. Pallas. f

PjvAte IX. Fig. 5, 6.

Sertularia pinnata. Pall. Elench. 136 S. fuscescens, Turt. Gmel- iv.

677. Turt. Brit. Faun. 213. Steiv. Elem. ii, 442. Lamour. Cor.

Flex. 195. Corallina, 85. Bosc, Vers, ili, 107 Dynamena pinnata,

Flem. Brit- Anim. 545. Dyn. tubiformis ? Lamour. Soland. Zooph. 12,

pi. 66, fig. 6, 7 La D. brunatre, Blainv. Aclinol. 483.

Hab. " Oceanus ad Prom. Lacertse, Cornubiae," Pallas. " On oyster-beds, common," Fleming. Frith of Forth, plentifully, Dr Coldstream.

Polypidom attached by tortuous tubular fibres, between two and three inches in height, pinnated with alternate branches, of a blackish or dusky horn colour, with a slight gloss on the surface, rather rigid

' Ellis calls him " a sea-officer in the East India Company's service." Pro- bably the same Mr E., a surgeon, whom Petiver mentions amongst the contri- butors to his museum.

f Peter Simon Pallas, M. D. born at Berlin, Sept. 22, 1741 : elected V. R. S. in 1764 : died Sept. 8, 181 1. See Brewster's Edin. Encyclop. xvi, 278 ; Clarke's Travels, i, 458, &c. Pennant's Literary Life, p. 7 ; but above all Cuvier's Me- moir in Edin. New Phil. .Journ. iv. i). 211, &c.

128 Z. HYDROIDA. Sertularia.

when dry, straig-ht, flattish, jointed, with a pair of opposite cells on each interspace ; branches patent, mostly undivided, jointed like the stem. Cells tubular, the upper portion free, erecto-patent, with an even aperture often girded with two or three faint circular wrinkles. Pallas says that the cells incline to one side of the stem, a character which Dr Fleming- failed to observe, and which is not perceptible in any of the specimens sent me by Dr Coldstream. " Ab eodem la- tere," says Pallas, " ovaria in pinnis plerisque mediis crebra, in se- riem conferta, minuta, obverse conica, supra trituberculata, et inter tubercula osculo instructa."

9. S. HiBERNiCA, " greater and lesser branches alternately pin- nated ; denticles alternate, elliptical, ivith emarginate mouths ; vesicles ovate, with a, denticulate mouth and transverse undidated

stricB."

Sertiilaria pinnata, Templeton in Mag. Nat. Hist, ix, 468.

Hah. " Dredged up, with other marine productions, in the sound of Donaghadee. Received from Mr J. Gilles, Aug. 1805," Tem- pleton.

" The branching of this species is somewhat peculiar, each of the primary and secondary branches springing out at an angle of 40° or 50°. That part of the stem which bears the denticles is waved so as to bear each denticle on the projecting part ; the denticles are el- liptic, and the mouth of each apparently a little hollowed inwards, perhaps arising from the extremity being fractured ; the vesicles are ovate, with 4 or 5 blunt teeth surrounding the mouth, and divided into 6 or 8 portions by annulated undulating lines. It might be classed among the large and strong sertularias, the principal shoot being of the thickness of a sparrow's quill at its base, and 4 in. or 5 in. long. The branches shoot forth from opposite sides, the whole coralline thus assuming a flat form, to the extent of 4 in. or 5 in." Templeton^

10. S. NIGRA, cells nearly opposite, small, ovate, appressed, with

a scarcely everted aperture ; vesicles ovate or elliptical. — Pallas.

Vignette, No. 13, page 119.

Sertularianigra,Pa//. Elench.135. Turt. Gmel.iv.676. 5osc, Vers, iii. 106.

Turt. Brit. Faun. 212. Jameson in Warn. Mem. i. 365. Corallina, 86.

S. Lichenastrum, Lin. Syst. 1313. (exelus. syn.) Dynamcna

nigra, Flem. Brit. Anim. 545 La D. noire, Blainv. Actinolog. 484.

Hab. Lizard Point, Cornwall, Pallas. Coast of Aberdeenshire, Robert Brovm. Scarborough from deep water, Mr Bean. Coast of Northumberland at Dunstanborough Castle, Mr R. EmbJeton.

Sertularia.

Z. HYDROIDA.

129

Polypidom 3 or 4 inches high, rigid, pinnate, lanceolate, dusky or blackish-brown, varnished. Stalk straight, compressed, jointed, with a series of alternate cells on each side : pinnae alternate, close, bifa- rious, several originating from each space between the joints of the stalk, simple, narrow at their origins, filiform, often gangrened at the apex. The cells are arranged in a close row along each margin, and directed alternately to opposite sides (Fig. 13) ; they are small, ovato-tu bular, short and adnate with a wide mouth having a small tooth on the outer edge. Vesicles unilateral, superior, elliptical or orate, sub-pedicellate, smooth.

Fie/. 15.

To this description, derived from specimens furnished by Messrs Bean and Embleton, I append that of Pallas, for Milne-Edwards denies the identity of his nigra with the British species (^Lcim. Anim. s. Vert. 2de edit. ii. 155) ; for which in my opinion there are no sufiS- cient grounds, but a comparison of the descriptions will enable every one to decide for himself. " Radices sunt tubi intestinuliformes, lu- tescentes, implexi, usque ad pinnarum originem assurgentes. Stit'ps ad summum quadripollicaris, simplex, pennata, sublanceolata, testaceo nigra et tenuior molliorque quam tubuli radic antes. Rachis stirpis est tubulus crassitie fere calami avenacei, compressus, e planiusculis lateribus, et ipsis denticulatis, pinnas proferens. Pinnce s. ramuli

I

130 Z. HYDROIDA. Sertularia.

teretiuscuH, depress!, lineaves, saepe longissimi, tenuiter a scapo ori- iintur, bifariam serrulati denticulis, uti ipse quoque scapus s. rhachis. Denticuli (sic potius in hac specie vocandi) subtubulosi, exigui, sim- plices. Ovaria ab altero stirpis latere in ramulis crebra, secunda, parallela, versus rami extremitatem sensim minora, membranacea, stirpi concoloria, obovato-subquadrangula, clan§a."

11. S. TAMARiscA, cells opposite^ tubular, the upper half di- vergent ivith a wide aperture sinuaied on the margin ; vesicles oval, truncate, loith ttvo small points at the corners and a tuhu- lous mouth. Ellis.

Plate X. Fig. 2, 3, 4.

Sea Tamarisk, Ellis, Corall. 4, no. 1, pL 1, fig. a, A Sertularia tama-

risca, Lin. Syst. 1307- Pall. Elencli. 129- Ellis and Soland, Zooph. 36. Berk. Syn. i. 216- Tiirt Gmel. iv. 676. Turt. Brir. Faun. 212. Stein. Elem. ii. 441. Bosc, Vers, iii. 106. Lamoiir. Cor. Flex. 188.

Corallina, 82. Lam. Anim. s. Vert. 2de edit. ii. 133 Dynamena ta- ^

marisca, Flem. Brit. Anim. 543 La D. tamarisque, Blainv. Acti-

nol. 483. Hah. On old shells in deep water, not common. Near the island of Dalkey, t the entrance of the harbour of Dublin, Ellis. Near Aberdeen, Dr David Skene. Frith of Forth, Dr Coldstream. Very- rare at Scarborough, Mr Bean.

Polypidom from four inches to " sometimes nearly a foot" in height, rooted by a creeping vermicular fibre, stout and erect, denticulated throughout, bifariously branched, the branches alternate, rather dis- tant, either simple or semipennated with secondary shoots, for these appear only to spring from the upper side of the branch, and are erect. The cells ai'e of a thin transparent corneous texture, large, smooth, exactly opposite, in approximated pairs, the upper half free and di- vergent, and the margin of the aperture obsoletely tridentate. Ve- sicles large, unilateral, scattered, obcordate or pyriform with a tubu- lar aperture. It seems that the little spine on each side is dependant on the age of the vesicle, and not perceptible when this is young. When mature it is filled with orange-coloured ova — In the thin tex- ture of the polypidom generally, and in the form of its cells, this spe- cies resembles Sert. rosacea ; but its robust habit, and the manner of its branching, give it at least equal claims to affinity with the fol- lowing.

12. S. ABiETiNA, cells nearly opposite or suhaltemate, ovato- tuhular, the mouth entire ; vesicles oval.

Plate X. Fig. 1, 1. Abies marina, Ger. emac. 1374, fig. Sibbald. Scot. ill. lib. quart. 55

Sertulakia. Z. HYDROIDA. 131

Corallina marina abietis forma, Rati, Syn. 35, no. 12. Bast. Opusc.

Subs. 41, tab. '2, fig. 6 ; and tab. 7, fig. 1 — 3, pessimal Muscus ma-

rinus major argute denticulatis, Plunk. Phytog. tab. 48, fig. 5. Raii,

Hist. i. 78 Muscus maritimus filicis folio, Morris. Plant. Hist. iii.

650. Uib. 9, fig. 1 Sta-fir, Ellis, Corall. 4, no. 2, pi. 1, fig. b. B.

Sertularia abietina, Z(7i7i. Syst. 1307. Pall Elench. 133. Mull

Zool. Dan. prod. 265. Ellis and Soland. Zoopli. 36. Berk. Syn. i. 216. Turt. Gniel. iv. 676. Blumenb. Man. 273. Wern. Mem. i. 564. Turt. Brit. Faun. 212. Stew. Elem. ii. 441. Lam. Anim. s. Vert. ii. 116, 2de edit. ii. 141. Stark, Elem. ii. 440. Risso, L'Europ. merid- V. 311. Lamour. Cor. Flex. 189. Corallina, 81. Bosc, Vers, iii. 106. Hogg's Stock. 31. Johnston in Trans. Newe. Soc ii. 256. Templeton

in Mag. Nat. Hist- be. 468 Dynamena abietina, Flem. Brit. Anim.

543 La Sertularie sapinette, Bluinv. Actinolog. 480, pi. 83, fig. 6.

Hah. On shells and stones in deep water, common. " This elegant coralline is frequently found on our coast, adhering- by its vermicular tubes to most kinds of shells : it grows very erect, and is frequently infested with little minute shells called Serpulas." — Ellis. Polypidom from 4 to 6 inches high, of a yellowish horn co- lour, smooth and varnished, stout, regularly pinnate, the stem flat- tened, slightly zigzag ; the branches rather close, linear, alternate, bifarious, simple, or sometimes pinnated. Cells g-enerally semialter- nate, rather small, bellied at the base with a narrow everted neck and plain aperture, so as somewhat to resemble a Florence-flask. Vesicles scattered, subsessile, proportionably small, smooth, ovate, with an even shortly tubulous mouth : they are produced pi'incipally in the winter season, when they are sometimes " in such abundance as al- most to cover the denticles, but placed in a very regular order," El- lis, and always on the upper edge of the branch from which they originate.

13. S. FILICULA, cells of the form of a Florence-flask^ opposite., a single one in the axilla of each pinna ; vesicles pear-shaped^ smooth^ the aperture shortly tubulous, entire. Hudson. *

Plate XI. Fig-. 1, 1. Sertularia filicula or Fern Coralline, Ellis and Soland. Zooph. 57, pi. 6, fig. c, C. Turt. Gmel. iv. 681. Bosc, Vers, iii. 114. Turt. Brit. Faun. 215. Stew. Elem. ii. 445. Jameson in Wern. Mem. i. 564. Lam. Anim. s. Vert. ii. 119. Lamour. Cor. Flex. 188. Corallina, 82. Johnston in Trans. Newc. Soc. ii. 257. Hogg's Stockton, 32 S.

• William Hudson, a London apothecary, elected F. R. S. in 1761 : the author of the " Flora Anglica," the publication of which, in 1762, " marks the establishment of Linnican principles of Botany in England, and their applica- tion to practical use." — Sir J. E. Smith.

132 Z. HYDROIDA. Sertularia.

ftbietina, /3, Pall. Elench. 134 DjTiamena filicula, Flem. Brit. Anim.

544. La D. fUicule, JSlainv. Actinolog. 48-3.

Ilab. Parasitical on sea- weeds, particularly on the entangled roots of Laminaria digitata. Coast of Yorkshire, Hudson. Scarborough, Ellis. Frequent about Seaton, Hartlepool, Whitburn, and other places on the coast of Durham, Hogg. Cullercoats, Northumber- land, ^bs. ^/rfer. Diinstanhorongh, H. Embleton. Common on the shores of N. Durham and Berwickshire, Go J. Frith of Forth, Ja77ieson.

Polypidom arising from a creeping fibre, 1 to 4 inches in height, spreading bifariously, irregularly branched, slender and flex- ible, of a straw-yellow or brownish colour, homologous throughout; the rachis zig-zag, or " bent to and fro into alternate angles," close- ly pinnated, the pinnae shooting from every bend alternately on op- posite sides, linear, patent, simple or composite. Cells closely set, minute, giving a serrulated appearance to the ramifications of the polypidom, shaped something like a Florence-flask, smooth, the aper- ture oblique, entire. The vesicles are rarely produced, nor have I seen a specimen with them : they are represented by Ellis as of a pear shape with a short tulnilous aperture.

This, like its ally the S. abietina, is often infested with Serpulae, but it is a much more delicate species, and, notwithstanding the si- milarity of their specific characters, perfectly distinct. " The singu- larity of its waved stem, with its erect single denticle at the insertion of the branches, together with the single pair of denticles on each part of the stem, that form the angles, make it a very distinct spe- cies from any of this genus." Ellis.

14. S. OPERCULATA, cells Opposite, inversely conical, the aper- ture patulous, obliquely truncate, pointed on the outer edge, with two small lateral teeth ; vesicles obovate. Mr Newton.

Plate XL Fig. 2, 2. Muscus marinus denticulatiis, procumbens, caule tenuissimo, denticulis bi- jugis, Rail, Hist. i. 79. Morrison, Plant. Hist. Oxon. iii. 650, tab. 9,

fig. 3. Pluhenet, Phytogr. tab. 47, fig. 11 Corallina muscosa denti-

culata procumbens, Raii, Syn. 36, No. 18 Sea- Hair, Ellis, Corall. 8,

No. 6, tab. 3, fig. h- B. Sertularia operculata, Lin. Syst. 1307- El- lis and Soland. Zooph. 39. Berk. Syn. i. 216. Turt. Gmel. iv. 676. Jarneson'irv Wern. Mem. i. 564. Turt.Wit. Faun. 212. Steiv. Elem. u. 441. Base, Vers, iu. 106. Lam. Anim. s. Vert. u. 118. Hogg's Stockton, 32. Johnston in Trans. Newc. See. fi. 258, plate 11, fig. 2.

Templeton, ut supra cit, 468. S. usneoides. Pall. Elench. 132

Dynamena operculata, Lamour. Cor. Flex. 176. Corall. 78. Flem. Brit. Anim. 544 — La Dynamene operculte, Blainv. Actinolog. 483, pi. 83, fig- 5.

Sertularia. Z. HYDROIDA. 133

Hab. Near low- water mark on Fuci. particularly on the stalks of Laminaria digitata. Common on all parts of the British coast.

Grows in tufts from 2 to 4 inches high. The shoots are slender and neat, filiform, tlexuose or widely zig-zag, always erect, alternate- ly hranched, the branches erect, and, like the first shoot, serrulated with the polype- cells which are exactly opposite, and less everted than is usual to the genus. The outer angle of the aperture of the cell is produced into an acute point, and there is a sharp tooth on each side, which is omitted in the otherwise admirable figure of Ellis, although it could not escape his lyncean eye. * The vesicles are irregularly scattered on the branches, large, smooth, egg-shaped, the top often covered with a sort of rounded operculum : they are produced abun- dantly in the winter season and in spring, when indeed, I think, the ovaries appear on the greater number of this order of corallines. It was from the great resemblance of these vesicular ovaries to the cap- sules of mosses, that the early botanists drew an additional argument in behalf of the vegetability of the corallines themselves ;f and a Dar- winian might be, perhaps, forgiven were he even now to feign how the Nereides stole them from the mossy herbelets of Flora's winter and vernal shews, to deck and gem the arbuscular garnitures of their own coral caves ! J

The shoots are usually so little waved that Pallas' term " subflex- uosi" is very appropriate, but in the collection of Dr Coldstream there

* " Zoophytorum lynceus Ellisius," Lin. Syst. 1071.

f " These vesicles appearing at a certain season of the year, according to the different species of corallines, and then falling off, like the blossoms or seeds of plants, has made some curious persons, who have not had an opportunity of see- ing the animals alive in the vesicles, conclude them to be the seed-vessels of plants ; and into this mistake I was led myself, in the account laid before the Royal Society in 1752. In which account I had taken some pains to point out the great similitude between the vesicles, and denticulated appearance of some of these corallines ; and the tooth-shaped leaves and seed-vessels of some spe- cies of land-mosses, particularly of the Hypnum and Bryum." — Ellis, CoralL In- trod. be.

\ " Nymphs ! you adorn, in glossy volutes roll'd,

" The gaudy conch with azure, green, and gold.

*«*■♦••*

" You chase the warrior shark, and cumbrous whale,

" And guard the mermaid in her briny vale j

" Feed the live petals of her insect-flowers,

" Her shell-wrack gardens, and her sea-fan bowers ;

" With ores and gems adorn her coral cell,

" And drop a pearl in every gaping shell."

Botanic Garden, Canto iii.

134 Z. HYDROIDA. Sertularia.

is a larg-e specimen, from the Frith of Forth, in which they are re- markably zig-zag or kneed, so as to give it a pecuhar character and appearance. In the same collection are specimens from the Cape of Good Hope, which differ in no respect from those of our shores.

15. S. AUGE'STE A, polT/pidojn cauliferous ; cells nearly oppo- site or suhalternate, urceolate, acutely pointed^ the upper half di- varicated ; vesicles oval. Merret.

Plate XII. and Plate XI. Fig. 3, 3. Corallina miiscosa, alterna vice denticulata, ramulis in creberrima capilla-

menta sparsis, Rail, Syn. i. 36, No. 17. Muscus maiinus denticulatus

minor ramulis in creberrima eapillamenta sparsis, Pluknet, Phytog. tab.

48, fig. 3 Muscus marinus minor denticulis alternis, Morris. Hist.

Plant. Oxon. iii. 630, tab. 9, fig. 4 Squirrel's-tail, Ellis, Corall. 6,

No. 4, pi. 2, fig. c, C. Sertidaria cupressina, /3, Lin. Syst. 1308

S. argentea, Ellis and Soland. Zooph. 38. Tiirt. Gmel. iv. 677. Wern. Mem. i. 564. Berk. Syn. i. '216. Tiirt. Brit. Faun. 213. Stew. Elem. ii. 442. Bosc, Vers, iii. 108- Lam. Anim. s. Vert ii. 117. Lamonr. Cor. Flex. 192, Corall. 84. Hogg's Stockton, 32. Templeton in lib.

cit. 468. Johnston in Trans. Newc. Soc. ii. 258, pi. xi. fig. 4 La

S. argentee, Blainv. Actinol. 480 Dynamena argentea, Flem. Brit.

Anim. 544. Hab. In deep water. On oysters and other large bivalved shells, as also on the stalk of Laminaria digitata, common.

Polypidom from 6 to 18 inches high, caulifei"ous, the stem percur- rent, fihform, waved or straight, smooth, of a dark brown colour, di- vided at rather wide but regular intervals by an oblique joint, clothed with short panicled dichotomous branches which spread out on every side, and being all of the same size or nearly so, (excepting at the bottom where they are less branched and smaller, and at the top where they also frequently become gradually shortened,) the whole coralline assumes somewhat of the shape of a squirrel's tail, and has given ori- gin to its English name. Two branches usually arise from each in- ternode of the stem, and they come off in such a manner that four or five of them complete a whorl. The polype-cells on the stem are alternate, appressed, and appear to be less than those on the branches, which are placed in two I'ows with their orifices inclined to one side ; they are bellied like a Florence-flask with a narrow divaricated neck terminated with a small oblique aperture : on some of the branchlets every pair is separated by a joint or stricture, while on others several pairs occur in succession without the interference of such a structure. Vesicles scattered, oval, smooth, attenuated at the base.

In young specimens of an inch or two in height the polypidom is simply pinnate, and as it rises the branches gradually divide into more

Sertularia. Z. HYDROIDA. 135

numerous seg-ments. In Plate XI. Fig. 3, I have given a fig-ure of such a specimen selected from many others on account of its greater diverg-ence from the usual character of the species. When, on the contrary, the polypidom attains a foot or more in height, the lower half of the stem loses its branches and cells, and becomes entirely naked. I think it likely that such a specimen, of the unusual size of 3 feet, constitutes the Sertulm'ia uber of Sir J. G. Dalyell in Edin. New Phil. Journ. xvii. 412.

16. S. CUPRESSINA, polypidom cauliferous ; cells nearly op- posite, tubulous, adnate, the aperture scarcely contracted, bilabiate, uiith two minute spinous teeth ; vesicles nearly oval. — Ellis.

Plate XIII.

Sea- Cypress, ^ffis, Corall. 7, No 3, pi. 3, fig. a, A. Sertularia cupres-

sina, Lin. Syst. 1308. Ellis and Soland. Zooph. 38. Berk. Syn. i. 216. Turt. Ginel. iv. 677. Wern. Mem. i. 564. Turt. Brit. Faun. 213. Stew. Elem. ii. 442 Bosc, Vers, iii. 108. Lam. Anim. s. Vert, ii. 118. Lamour. Cor. Flex. 192. Corall. 84. Hogg's Stock. 32. Tem- pleton in loc. cit. 468. Stark, Elem. ii. 440, pi. 8, fig. 12. Risso,

L'Europ. merid. v. 311 La S. cypres, Blainv. Actinol. 480 Dy-

namena cupressina, Flem. Brit. Anim. 543.

Hab " The Sea-cypress is chiefly found in deep water on the coast of Yorkshire, Scotland, and the north of Ireland," Ellis. Scarbo- rough, Mr Bean. Frith of Forth, Jameson. Cork Bay, Mr J. V. Thompson. On the shore of iNIagilligan Strand, County Derry, TempJeton.

This is in general a larger and stouter species than the preceding, with longer branches more decidedly fan-shaped, the pinnae being closer and more parallel to one another. The cells are in two rows, nearly opposite, smooth and pellucid, adnate, with the margin of the comparatively wide aperture sinuated so as to form two or some- times three prominent denticles. The branches in some specimens are gTacefully arched, bending as it were under the load of pregnant ovaries which they carry, and which are arranged in close-set rows along the upper side of the pinnae. They are of an oval shape, smooth, attenuated at the base, with sometimes a sharp spine at each corner of the apex, but these are oftener absent.

This and the preceding have a distinct stem, in which they differ from all the other native species, which are pre-eminently frondose or homologous, the offsets and pinnae being in all respects the same as the primary shoot. Pallas maintains that they constitute but one

species, his S. cupressina, Elench. 141 the charactei's assigned to

them respectively being far from specilical, since he found, on one

136 Z. HYDROIDA. Sertularia.

and the same specimen, that the young vesicles had long- spines at their tops, the more mature shorter ones, and on full-grown vesicles they were nearly or altogether obsolete ; while bluntly tubulous and acutely pointed cells occurred promiscuously, on the same stalk, in specimens of every size and exterior habit. Linnaeus, apparently swayed by these assertions, followed Pallas ; but Ellis, in a later work, adhered to his first opinion, for, " besides the difference of their denticles (cells) and ovaries," which he evidently regarded as per- manent, they have, he says, " quite a different habit and manner of growing." All subsequent writers have assented to Ellis's views, most of them, at the same time, expressing- a suspicion of their cor- rectness, and my own limited observations have possessel me with the same dubiety. Specimens can be readily produced which, from habit and the figure of their cells, will be at once pronounced the re- presentatives of distinct species, but a larger examination may lead to another conclusion. I have seen no specimens of S. cupressina with the cells of S. argentea, * but I have seen several which, from their habit, I would refer to the latter, with the cells and vesicles of the former. Such a specimen is figured in Plate XII. I can also state that on the same specimen I have observed cells that might be con- sidered as belonging to either species ; and with these facts I should, perhaps, have amalgamated the synonymes, had I not been aware that some of our best naturalists, for example Bean and J. V. Thomp- son, are opposed to the junction. " Besides," to adopt the words of Professor Lindley in a somewhat similar discussion, " our daily ex- perience shows us that excessive analysis is far preferable to excessive synthesis, especially for the purposes of students ; the former leads to no other inconvenience, than that of increasing the degree of in- vestigation which species must receive to be understood ; the latter has a constant tendency to render investigation superficial, and cha- racters confused," Syn. of the British Flora, Pref. p. ix.

Professor Jameson has inserted Sertularia cupressoides among those species found in the Frith of Forth, Wern, Mem. i. 564 ; and in the work entitled " Corallina," p. 83, the elegant Aus- ti'alasian S. elongata and S. pectinata are said to be found on

the English coast. I believe there is some error in all these in- stances.

I have repeatedly observed on oyster-shells, and among the roots

• It deserves to be remarked, in connection with this point, that the charac- ters of S. argentea given by Lamarck are really those of S. cupressina ; and this has ascribed to it the diagnostics of S. argentea.

TiiuiARiA. Z. HYDIIOIDA. 137

of corallines, a sessile vesicular body filled with milk-white granules, resembling- very exactly the oviferous vesicle of a Sertularia, but of what species I am unable to say, if indeed it belongs to any. It is rooted, subsessile, roundish, slightly flattened on the sides, smooth, with a short tubulous even aperture. Fig. 10, page 92. It has no at- tachment to any organized body. Can it be the nidus of some mi- nute Fusus or Purpura ?

7. Thuiaria, * Fleminor. Character. Pulypidom plant-like, rooted hy a tubular Jihre, erect, dichotomously branched or pinnated ; the cells sessile, bise- rial, adnate to the racliis or " imbedded in the substance of the stem and branches ;" vesicles scattered. — Polypes hydraform.

1. Th. Thuia, cells ovato-elliptical, rather acute; vesicles pear-shaped. Sir Robert Sibbald.f

Plate XIV. and XV. Fig, 1, 2.

Plaiita marina equiseti facie, Sib- Scot. ill. ii. lib. iv. 55, tab- 12, fig. 1

Fucus equiseti facie, Ibid- lib. i. 56. Rail, Syn. 50, no. 47 — ^ — Bottle- brush Coralline, Ellis, Corall. 10, no. 9, pi. 5, fig. b. B Sertularia

thuja, Z(«. Syst. 1308. Pall. Elench. 140. Ellis and Soland. Zooph. 41. Berk. Syn. i. 217. Turt. Gmel. iv. 678. Wern. Mem. i. 564. Turt. Brit. Faun. 213. Bosc, Vers, iii. 109. Slew. Elem. ii. 442. La- moitr. Cor. Flex. 193. Corall. 84. Hogg's Stock. 32. Risso L'Europ.

Mend, v, 311 Cellaria thuia, Lam- Anim. s. Vert ii. 339. Stark,

Elem. ii. 439 Thuiaria thuia, Flem. Brit. Anim. 545. Johnston in

Trans. Newc See. ii. 261 — La Biseriare thuia, Blainv. Actinol. 482, pi. 81, fig. 3.

Hab. On shells from deep water. " They are found on the coast

Formed from ^u'ttt — a cedar. There is a Thuarea in Botany, so near to the zoophytical genus in sound as to render this name objectionable. The Thu- area is formed from the name of the botanist A. du Petit-Thouars.

■f There is a very interesting life of Sir Robert, written by himself, in the Analecta Scotica, v. i. p. 126 et seq. It is printed in a separate form with the title " The Autobiography of Sir Robert Sibbald, Knt. M. D. ; to which is pre- fixed a short account of his MSS." 8vo, published by Thomas Stevenson, Edin. 1833. The pamphlet forms the basis of his Life prefixed to the 20th vol. of the " Naturalist's Library," with which a portrait is also given. Sir Robert was born 15th April 1641 ; graduated in 1662 ; was knighted in 1682 ; and died probably in 1 722, for the precise date has not been ascertained. See Pulteney's Sketches of the Progress of Botany, v. ii. p. 4-8. The following Elogium is from the Second Series of the ATialecta Scotica, p. 153, Edin. 1837.

" Illustrata simul decorat, pariterque Sibaldum

" Scotia, scriptori lumine grata suo."

138 Z. HYDROIDA. Thuiaua.

of Scotland, and in the noi'tb of England, ])articularly about Scar- borough, where the fishermen have given them the name of Bottle- brushes," Ellis. " Very frequently found on the coast of Durham," J. Hogg. Common on N. Durham and Berwickshire, G. J. Leith shore, Jameson.

This remarkable coralline is sometimes a foot in height, generally less, affixed by a tubular fibre, which is sometimes agglutinated to others from other shoots, so as to form a lichen-like ci'ust concentri- cally wrinkled. Stem percurrent, erect, filiform, rigid, zig-zag, knotted, naked underneath, bearing on the upper part a cylindrical tuft of dichotomous short equal branches, coming off alternately and so disposed that four complete a whorl. The knots on the lower part are the remains of former branches which seem to drop off as the portion of the stem immediately beneath them successively loses its vitality. The stem has no cells, and neither it nor the branches are jointed. Cells close-pressed, arranged in two rows, sub-alternate, smooth, tapered from the base to a contracted orifice. Vesicles sub- pedicellate, pear-shaped, smooth, placed in clusters or solitary on the upper side and towards the base of the branches ; they are produced mostly in the winter season, and are filled with a milk-white grumous fluid previous to the discharge of the ova.

Young specimens of this polypidom are simply pinnate, but these may be always distinguished from the following by the greater inter- vals between the origin of the pinnae, and by the shape of the cells. The Fig. 1,2 of Plate XV. represents a specimen of this kind, which has been the more readily introduced, since it exhibits the living polypes in an active state, and proves that the coralline has no relationship to Cellaria. — The Sertularia thuia of Fabricius in his Fauna Groen- landica, p. 444, I am inclined to refer to Sert. pumila.

2. Th. articulata, cells ovate, obtuse or truncate ; ovarian vesicles elliptical. Ellis.

Plate XV. Fig. 3, 4.

Sea-Spleenwort or Polypody, £ffis, C'orall. 11, no. 10, pi. 6, fig. a, A

Sertularia articulata, Pall. Elench. 137 S. Lonchitis, jBffis and A'o-

land. Zooph. 42 S. Liclienastrum, J5erA. Syn. i. 219. Turt. Gmel.

iv. 683. Turt. Brit. Faun. 216. Stew. Elem. ii. 447. Bosc, Vers,iii.

119. Cellaria Lonchitis, Lam. Anim. s. Vert. ii. 1.39. Thuiaria

articulata, Flem. Brit. Anim. 545 La B. articulee, Blainv. Actinol.

482. Hab. On shells and stones in deep water, very rare. In the har- bour of Dublin, Ellis. At Scarborough, 3Ir Bean.

Polypidom about 4 inches high, pinnate, lanceolate, corneous, sub-

3

Antennularia. Z. HYDliOlDA. 139

pellucid, the stem nearly equal in diameter throughout, compressed upwards, finely wrinkled when dry, divided by joints not regularly equidistant, naked on the lower halt, pinnated above and celliferous: pinnae simple, patent, rather close-set, not exactly opposite nor yet properly alternate. Cells in a single series along each side, semial- ternate, ovato-tubular, short with a round plain aperture. Vesicles issuing from both sides of the pinnae, most numerously from the up- per, subpedicellate, elliptical, smooth, the oi'ifice contracted and even. , Through the liberality of Mr Bean, I am enabled to give a figure — the most perfect one which has been yet published — of this rare species. Its synonymes are somewhat confused. Pallas aflSrms, cor- rectly in my opinion, that the Sea-Spleenwort of Ellis is not the Ser- tularia Lichenastrum of Linnaeus as generally asserted, and he has described a different species considered by him as identical with the Linnsean. The figure of Ellis is quoted by Pallas as an admirable re- presentation of his own S. articulata, but in the description of this the branches or pinnae are said to be opposite, whereas in Ellis's fi- gure, and in our own, although less decidedly, they are regularly al- ternate. Elhs notices under his S. Lonchitis a foreign variety with op- posite cells and pinnae, having " the joints both on the stem and branch- es much closer together ;" and it will probably be found that this con- stitutes a distinct species, hitherto confounded with others nearly allied.

8. Antennularia,* Lamarck. Character. Polypidom ■plant-like^ hoimy, simple or hranch- ed irregularly, the shoots fistular, jointed, clothed with hair-like verticillate hranchlets : cells small, sessile, campanulate, unilate- ral : vesicles scattei'ed, unilateral — Polypes hydraform.

1. A. ANTENNiNA. — Mrs Ward, -f-

Plate XVI.

Lobster's -boin coralline or Sea-beard, Ellis, Corall. 15, no. 14, pi. 9, fig. a, b, A. B. a Phil. Trans, xlviii. G30, tab. 22, no. 3. Phil. Trans.

abridg. x. 491, pi. 12, fig. 3, C. Sertularia antennina, Lin. Syst.

1310. Pall. Elench. 146. Ellis and Solaiid. Zooph. 45. Berk. Syn. i. 217. Tint. Gmel. iv. 679. Wern. Mem. i. 564. Turt. Brit. Faun.

* From Antennula, diminutive oi antenna, a term applied to the feelers of in- sects.

•)• " Found on the rocks by Mrs Ward, an ingenious gentlewoman of Gisburgh in Cleveland, Yorkshire, and by her named Sea-beard ; I suppose from its grow- ing in a thick tuft; Mr Lawson." — Raij.

140 Z. HYDROIDA. Plumularia.

214. Stew. FAem. u. 443. i?osc, Vers, iii. 1 1 1 . Antennularia anten-

iiina, Flem. Brit. Anim. 546. Johnston in Trans. Newc. Soc. ii. 260. Var. 1. The stem simple — Corallina astaci corniculorum semula, Raii, Syn.

i. 34, no. 10. Corallina affinis, nonramosa, Pluhen. Almag. Bot. 119.

Muscus marinus s. coralloid. non ramosus, erectus, Pluhen. Phytog.

tab. 48, fig. 6 Sertularia antennina, Hogg's Stock. 33 Nemer-

tesia antennina, Lamour. Cor. Flex. 163, Corall. 71 Antennularia, in-

divisa, Lam. Anim. s. Vert. ii. 123. 2de edit. ii. 156. Templeton in Mag.

Nat Hist. ix. 468 L'Antennulaire simple, Blainv. Actinolog. 486,

pi. 83, fig. 3. Var. 2. The stem branched — Corallina minima, Ger. Herb. emac. 1572, no. 4, quoad fig C. ramosa cirris obsita, Raii, Syn. 35, no. 11 Ser- tularia seticornis, Hogg's Stock. 33 Nemertesia ramosa, Lamour.

Cor. Flex. 164. Corall. 71 Antennularia ramosa. Lam. Anim. s.

Vert. ii. 123. 2de edit. ii. 156- Stark, Elem. ii. 440. Templeton in ]ib.

cit. 468 L'A. rameuse, Blainv. Actinolog. 486.

Hab. On shells and rocks in deep water, frequent. " In littore Dubrensi colleg-it D. Dare Pharmacopseus Londinensis," Bai/. Sus- sex coast, Ellis. From deep water in the Frith of Forth, Jameson. Common on the coasts of Durham, Northumberland, and Berwick- shire, G. J. Cork harbour, J. V- Thompson. (I.) " On the shore of Dublin Bay ; (2.) Found on the shore of Belfast Lough," Temple toti.

Stems clustered, rooted by numerous implexed tubular fibres, erect, straight, attaining a height of 8 inches and upwards, cylindrical, of a clear yellowish-horn colour, irregularly branched or undivided, and in the latter instances resembling, when dried, the Lobster's antenna, to which they have been appropriately compared. The branches are exactly like the primary shoot, and are equally beset with hair-like branchlets arranged in numerous whorls. These are often broken short in specimens cast on shore after storms, but in recent ones dredg- ed from their native sites they are as long as represented in our fi- gures. They carry the polype cells, which are distant, small and cam- panulate with entire rims, and divided from each other by a joint. The ovarian vesicles are situated in the axils of the whorls, subpedi- cellate, ovate, smooth, with a subterminal aperture.

I can detect no essential difference between the two varieties, and I have had, through the kindness of friends, an opportunity of exa- mining specimens from various parts of the coast.

9. Plumularia ;* Lamarck. Character. Polypidum plant-like^ rooted, simple or branch-

» Formed from Plumula, the dimin. of Pluma, a feather — I have, in common with most French authors, adopted the generic names of Lamarck in preference

Pi.uMULAuiA. Z. HYDROIDA. -141

ed, the shoots and offsets plnmous : cells small, sessile, unilateral, usually seated in the axilla of a horny spine : vesicles scattered, unilateral. — Polypes hydrajvrm.

* Stem a single tube. 1. P. FALCATA, stein leaved, branched ; branches alternately pennated ; cells close-ranked, shortly tubulous with a plain rim ; vesicles oblong- oval. Merret. *

Plate XVll. Fig I, 2. Corallina mnscosa pennata, ramulis et capillamentis falcatis, Raii, Syn. i.

36, No. 16 Muscus pennatus, ramulis et capillamentis falcatis,

Pluken. Phytog. tab- 47, fig. 12 Muscus maritimus pennatus ramu- lis et capillamentis falcatis, Morris. Plant, hist. Ox. iii. 650, tab. 9, fig.

2 Sickle Coralline, Ellis, Corall. 12, No. 11, pi. 7, fig. a, A. and

pi. 38, fig. 6 Sertularia fdlcata, Li?i. Syst. 1309. Pall. Elench. 144.

Ellis and Soland. Zooph. 42- Berh. Syn. i. 217. Turt. Gmel. iv. 679. Blumenb. Man. 278. Wern. Mem. i. 564. Tart. Brit. Faun. 213. Stew.

Elem. ii. 443. Bosc, Vers, iii. 110. Hogg's Stock. 32 Aglaophenia

falcata, ZamoM/-. Cor. Flex. 174. Corall. 77 Plumulariafalcata, Zam.

Anim. s. Vert. ii. 125. 2de edit. ii. 160. Grant m Edin. New Phil. Journ. i. 155. Flem. Brit. Anim. 546. Johnston in Trans. Newc. Soc.

to those of Lamouroux, although aware that the claim of priority is generally allowed to the latter ; but let us hear what Milne-Edwards says — " Pendant que Lamarck preparait le grand ouvragedont le second volume est consacreaux Polypes, Lamouroux s'oecupait du meme sujet, et fit paraitre a Caen un traite special sur les Polypiers coralligenes flexibles. D'apres la date de la presenta- tion de son manuscrit a I'Institut, on pourrait meme lui attribuer I'anteriorite sur Lamarck, et penser que ce dernier savant, nomme par I'Academie des Sciences commissaire pour I'examen du memoire de Lamouroux, avait profite de cette circonstance pour s'approprier les resultats obtenus par ce zoologiste. Un au- teur recent semble porte a croire que les choses se sont passees de la sorte ; mais les traditions du museum prouvent qu'il n'en est rien, et je me plais a ren- dre ici toute justice a la conduite de Lamarck. En efFet, M. Valenciennes, qui etait alors attache a Lamarck en qualite d'aide-naturaliste, m'a assure que de- puis long-temps toutes les divisions generiques etablies par ce professeur dans la classe des Polypiers se trouvaient indiquees dans la collection publique de mu- seum, et que pour faciliter le travail de Lamouroux sur le meme sujet, Lamarck avait mis genereusement a sa disposition toutes les richesses de cet etablissement deja denominees et classees par ses soins." — Ann. des Sc Nat Part. ZooL Tom. vi. second ser. p. 12-

* For an account of Dr Christopher Merret see Pulteney's Sketches, v. i. p- 290, &c J and Thomson's Hist, of the Roy. Soc. p. 22. He was born in 1614 ; was one of the original members of the Royal Society; and died in 1695. Ray's character of him in 1688 is, — " annis et scientia gravis, de Professione sua deque Repub. Botanica optime meriti." Hist. Plant, ii. prsf. Contrast this with the character in Sir J. E. Smith's Eng. Flora, i. pref. vii-viii.

142 Z. HYDROIDA. Plumularia.

ii. 259. Templeton in Mag. Nat. Hist. ix. 466. Risso, L'Europ. merid.

V. 31.3 I.a P. en faux, Blainv. Actinolog. 477.

Hah. On shells and rocks near low water-mark and in deep water. A common and very eleg-ant species, generally from 4 to 6 inches in height, rising- in wide spiral turns, and sending out from its filiform percurrent stem, at regulated intervals, alternate spreading plumous branches which are placed one above the other on the outer side. Pinnae alternate, bifarious. In young speciniens the branches are two- ranked and alternate, and I have seen this character remain in one specimen of considerable size. There are no cells on the spiral stem, but they occur on the branches as well as on the pinnae, and are arranged in two rows pointing alternately to opposite sides. There is a fine figure of the coralline in the centre of the curious frontis- piece to Ellis's Essay ; and the magnified figure in tab. 38 is a more correct representation of the cells than that given in tab. 7, which has been drawn from a dried specimen. The ovarian vesicles are of uncertain occurrence, and I have seldom seen them ; they are scattered irregularly on the branches, stalked, ovate or pear-shaped, with a short tubulous aperture, and occasionally wrinkled longitudinally when dry* " This species is very common in the deeper parts of the Frith of Forth ; its vesicles are very numerous, and its ova are in full matu- rity at the beginning of May. The ova are large, of a light-brown colour, semi-opaque, nearly spherical, composed of minute transpa- rent granules, ciliated on the surface and distinctly irritable. There are only two ova in each vesicle ; so that they do not require any external capsules, like those of the Campanularia, to allow them suf- ficient space to come to maturity. On placing an entire vesicle? with its two ova, under the microscope, we perceive through the transparent sides, the cilise vibrating on the surface of the contained ova, and the currents produced in the fluid within by their motion. When we open the vesicles with two needles, in a drop of sea-water, the ova glide to and fro through the water, at first slowly, but after- wards more quickly, and their cilise propel them with the same part always forward. They are highly irritable, and frequently contract their bodies so as to exhibit those singular changes of form spoken off by Cavolini. These contractions are particularly observed when they come in contact with a hair, a filament of conferva, a grain of sand, or any minute object ; and they are hkewise frequent and remarkable at the time when the ovum is busied in attaching its body permanent- ly to the surface of the glass. After they have fixed, they become flat and circular, and the more opake parts of the ova assume a radiat- ed appearance ; so that they now appear, even to the naked eye, like

Plumularia. Z. HYDROIDA, 143

so many minute grey coloured stars, having the interstices between the rays filled with a colourless transparent matter, which seems to harden into horn. The grey matter swells in the centre, where the rays meet, aud rises perpendicularly upwards surrounded by the trans- parent horny matter, so as to form the trunk of the future zoophyte. The rays first formed are obviously the fleshy central substance of the roots, and the portion of that substance which grows perpendicularly up- wards, forms the fleshy central pai'tof the stem. As early as I could observe the stem, it was open at the top ; and, when it bifurcated to form two branches, both were open at their extremities, but the fleshy central matter had nowhere developed itself as yet into the form of a polypus. Polypi, therefore, are not the first formed parts of this zoophyte, but are organs which appear long after the formation of the root and stem, as the leaves and flowers of a plant." Professor Grant.

2. P. CRiSTATA, shoots simple, plumoiis, the pinna alternate ; cells in a close roio, cup-shaped ivitii a toothed margin and a short lateral spine ; vesicles gibbous, girt with crested ribs. Ellis. Plate XIX. Fig. 1—3, and Plate XX. Fig. 1.

The Podded Coralline, Ellis, Coiall. 13, no. 12, pi. 7. fig. b. B Ser-

tularia pluma, Lin. Syst. 1.309. Pall. Elench. 149. Ellis and Soland. Zooph. 43. Berk. Syn. i. 217- Tiirt. Gmel. iv. G79. Turt. Brit. Faun. 214. Stew. Elem. ii. 443. Bosc, Vers, iii. Ill, pi. 29, fig. 1, pe.ssima.

Lister in Phil. Trans, au. 1834, 369, pi. 8, fig. 2 Aglaophenia pluma,

Lamour. Cor. Flex. 170- Corall. 75 Plumularia eristata, Lam. Anim.

s. vert. ii. 125. 2de edit. ii. 161. Stark, Elem. ii. 440. Templeton'm Mag.

Nat. Hist. ix. 467. Risso, L'Europ. merid. v. 313 PI. pluma, Flem.

Brit. Anim. 546 La Plumulaire plume, Blainv. Actinol. 477

Sertolaria pluma, CavoL Pol. mar. 210, tav. 8, fig. 5 — 7.

Hah. On Fuci, particularly Fucus siliquosus, and sometimes " on muscles and other shells." Common on the southern coasts of Eng- land. Picked up on the shox'e at Stevenston, Ayrshire, Rev. D. Landsborough. On the coast of Ireland near Dublin, Ellis. On the shore of Belfast Lough, &c. 3Ir TempJeton.

Attached to sea-weeds by a flexuous horny anastomosing tubular fibre, which throws up, at intervals, plumous shoots from one to one and a half inch high : these are very elegant and erect when in the sea, but when dry become curved in a falcate manner with all their pinules, which are also frequently laid to one side. " Siccatione surculi sursum seu contrario modo qiiam fuerant, recurvantur, pin- nulseque curvatae ad invicem accedunt." Pallas. The polypidom is of a honey-yellow colour with a dark brown rachis, which is smooth, and divided by numerous oblique septa or joints, there being one be-

144 Z. HYDROIDA. Plumularia.

tween every pair of pinnae. Pinnae alternate, close, parallel, celluli- ferous on the upper side ; the cells separated by a joint and set in a sort of indentation in the stalk. They have been aptly compared by Ellis to the flower of the lily of the valley, being- of a campanulate form with the rim cut into eight equal teeth, while in front there is a stronger spinous process which does not project beyond the cell. The ovarian vesicles are large and remarkably curious : they are pro- duced both from the main stalk and pinnae, are shortly pedicellate, and resemble a swollen pod girded round with from 5 to 9 cristated ribs or bands proceeding from a dorsal tube, and rising- into short spines on the anterior margin. When recent " they are translucent, and six or seven dark oval masses can be seen within each. These seemed to be ova. The vesicle being torn up, and the ova allowed to escape, they were seen to be in form irregularly oval, but contain- ing an opake elongated body in their centre. (Fig. 6, p. 48.) The form of this central body varied in different ova, but it was generally some- what hammer-shaped. Neither the general mass of the ovum, nor this central body were seen to move." Dr Coldstream^ June 10, 1833. — Polypes " minute, delicate ; tentacula 10, annulated ; mouth infundibuliform." Dr Coldstream.

" Each plume," says Mr Lister in reference to a specimen of this species, " might comprise from 400 to 500 polypi ;" and a specimen, of no unusual size, before me has twelve plumes, with certainly not fewer cells on each than the larger number mentioned, thus giving 6000 polypes as the tenantry of a single polypidom ! Now many such specimens, all united too by a common fibre, and all the off- shoots of one common parent, are often located on one sea-weed, the site then of a population which nor London nor Pekin can rival ! But PI. cristata is a small species, and there are single specimens of PI. falcata, or Sertularia argentea, of which the family may consist of 80,000 or 100,000 individuals. It is such calculations, always un- der-rated, that illusti'ate the " magnalities of Nature," and take us by surprise, leaving us in wonderment at what may be the great ob- jects of this her exuberant production of these " insect-milhons peopling every way." But

" So He ordain'd, whose way is in the sea,

His path amidst great waters, and his steps

Unknown ; — whose judgments are a mighty deep,

Where plummet of Archangel's intellect

Could never yet find soundings, but from age

To age let down, drawn up, then thrown again,

With lengthened line and added weight, still fails ;

And still the ciy in Heaven is ' O the depth' !" — Montgomenj.

Plumularia. Z. HYDHOIDA. 145

I have a specimen of PI. cristata gathered in Cork Bay, and present- ed to me by J. V. Thompson, Esq., which is nearly 3 inches in height, spreading laterally, the rachis divided in a regular dichotoraous man- ner, and rough or muricated on one side, wherever it is naked of pinnae. The vesicles have from 7 to 9 crested ribs with a spinous dorsal keel. The roughness of the I'achis is produced by the remains of the deciduous pinnae. I give a figure of this specimen, (Plate XX. Fig. ],) as an additional proof that little reliance can be placed on ex- ternal habit as a character in determining the species of this order.

3. P. PENNATULA, plumous, the pimia opposite ; cells in a close roio, cup -like icith an unequally crenated margin, support- ed on the under side hy a lengthened incurved spinous process. Montagu.

Plate XVIII. Fig. 1, 2.

Sertularia perinatula, Ellis and Suland. Zooph. 56, tab. 7, fig- 1, 2- Bosc,

Vers, iii. 114. Fleming m Edin. Phil. Journ. ii. 83 Aglaophenia

pennatula, Lamour. Cor. Flex. 168. CoraU. 74 Plumiilaria penna.

tula, Lam. Anini. s. Vert ii. 128. 2de edit. ii. 165. Flem. Brit.

Anim. 546 La P. pennatule, Blainv. Actinolog. 478.

Hub. Coast of Devonshire, rare, Mr Montagu. " This coralline is as remarkable for the elegance of its form, as its likeness to the feather of a pen." Specimens from the seas of tropi- cal climates are from 5 to 6 inches high, but my British specimen, which I owe to the liberality of J. E. Gray, Esq., is scarcely one inch and a half. The polypidom rises from implexed tubular fibres : the lower portion of the cylindrical jointed rachis is naked, the upper pennate and gracefully proportioned. The cells are small with a waved margin and a little spine on each side, and they are seated in the axil of a long tubular incurved process which rises much above them. Lamouroux has conjectured that the PI. pennatula of Flem- ing is only a repetition of PI. myriophyllum ; and Milne-Edwards refers it to PI. cristata. I cannot see the slightest foundation for these suspicions.

4. P. FINN at a, stem plmnous, the pinnce alternate ; cells ra- ther distant, one on each internode, campanulate, leaning, the mouth entire ; vesicles ohpyriform, strongly toothed above. Dil-

lenius.*

Plate XVII. Fig. 4, 5.

* Born in 1687 at Darmstadt in Germany ; came to England in 1721 ; and died at O.xford in 1747. He was the first Professor of Botany there, and has not been equalled in celebrity by any successor. It is unnecessary to give particulars of

K

146 Z. HYDROIDA. Plumularia.

Fucoides setis minimis indivisis constans, Rail, Syn. i. 39, no. 7. tab. 2, fig. 2.

lit. a, (injm-ed and deprived of the pinnte. ) Sea Bristles, jE/fc, Corall.

19, no. 16, pi. 11. fig. a. A Sertularia pinnata, Lin. Syst. 1312.

Ellis and Soland. Zooph. 46. Berk. Syn. i. 219. Turt. Gmel. iv. 683. Turt. Brit. Faun. 215. Stew. Elem. ii. 446. Bosc, Vers, iii. 118.

Aglaophenia pinnata, Lamour. Cor. Flex. 172. Corall. 76.

Plumularia pinnata, Zam. Anim. s. Vert. ii. 127. 2de edit. ii. 164- Eisso, L'Europ. merid. v. 313. Johnston, Trans. Newc See. ii. 260,

and in Mag. Nat. Hist. vi. 498 La P. pinnee, Blainv. Actinolog.

477. Hab. On shells, stones and other corallines in deep water. " In littore maris pone Sheerness," D. Dillenius. At Brightelmstone and Whitstable, Ellis. Scarborough, Mr Bean. Cullercoats, Northum- berland, Mr J. Alder. Common in Berwick Bay, G. J. Frith of Forth, Dr Coldstream. Cork Harbour, J. V. Thompson, Esq.

In general about on,e inch and a half, but sometimes attains the height of four inches, very delicate, simple, plumous, white, and pretty. The rachis is compressed, straight, jointed, the internodes al)out six times longer than their diameter, and each giving origin to three pinnae, in which character I find an invariable and ready dis- tinction between this and the following species. There is a minute tooth-like spine, only visible under the microscope, between the cells, which are perfectly transparent, and admit a distinct view of the po- lypes. These have a reddish body and numerous tentacula. The vesi- cles are rarely produced, but then profusely, and the specimens on which I have seen them have lost almost all their polypiferous pinnae. At the base of the remnants they occur clustered, and are pear-shaped with an aperture cut into a circle of spinous teeth, or, as Ellis ex- presses it, " the tops of the ovaries are divided like a coronet."

5. P. SETACEA, pinnate, the pinncs alternate, one originating at each ringed joint of the rachis ; cells very remote, campanulate, ivith an even margin ; vesicles elliptical, smooth. Ellis. Plate XVIII. Fig. 3—5.

Corallina setacea, Ellis, Corall. tab. 38, fig. 4 Sertularia pinnata 0,

Lin. Syst. 1312 S. setacea, Pall. Elencli. 148. Ellis and Soland.

Zooph. 47. Turt. Gmel. iv. 683. Wern. Mem. i. 564. Turt. Brit. Faun. 216. Stew. Elem. ii. 446. Bosc, Vers, iii. 119- Hogg's Stock. 33. Lister in Phil. Trans, an. 1834, 371, pi. 8, fig. 4, but the vesicles

so eminent a man ; for his life I may refer the reader to Pulteney's Sketches V. ii. p. 154, &c. ; Thomson's Hist. Roy. Society, p. 26 ; and Brewster's Edin. Eneyclopffidia, v. vii. p. 742 ; a good article contributed by my worthy friend Dr Neill. Haller's notice of his friend is short, but interesting. Bib. Bot. v. ii. p. 124.

Plumulaiiia. Z. HYDROIDA. 147

belong to PI. i)iiiiiata Aglaopheiiia sotacea, Lainoitr. Cor. Flex. 172.

Coiall. 70 Pluimilaria setacea, Lam. Aniin. s. Vert, ii, 129. "ide

edit. ii. 165. Flem. Brit- ATiim. 547. Templeton in Mag. Nat. Hist.

ix. 467. Starh, Elem. ii. 440. Bisso, V Eiirop. merid. v. 313

La p. setacee, Blainv. Actinol. 177. Hab. Parasitical on other corallines, not uncommon. At Brigh- ton on flag, Lister. Frequent near Hartlepool, growing on the roots of the Palmated Fucus, Hogg, On scallop shells in the Frith of Forth, Jameson. Berwick Bay, G. J. Belfast Lough, Templeton. Co^k Harhour, Thompson.

In favourable sites this coralline will sometimes attain a height of six inches, but in general it is smaller, more delicate, and less plumous than PI. pinnata with which it has been confounded, although its habit and minuter characters prove it to be quite distinct. The stem is somewhat waved and regularly jointed, the joints consisting of two or three I'ings, and immediately under each joint the internode is somewhat enlarged in consequence of the pinna originating there, a single pinna only springing from under each joint, whereas in P. pinnata, as already remarked, three pinnae proceed from each inter- space, the joints of which, moreover, consist of a single fracture. The pinnae are jointed like the stem, celliferous, the cells small and dis- tant. At the base of each there is a minute tubular process (abor- tive cell ?), visible only with a high magnifier. The vesicles are el- liptical, smooth, with a narrow plain orifice, .and originate in the axils of the pinnae. — " The ova within were opake and yellow. Its polypi had from sixteen to nineteen arms, and when they were full blown it was an object of remarkable beauty." Lister.

6. P- Catharina, stem plumous^ the pinna opposite, hent inioards ; cells distant, campamdate icith an even margin ; vesi- cles scattered, pear-shaped, smooth. G. J.

Vignette, No. 8, page 79. Plumiilaria Catharina, Johnston in Mag. Nat. Hist. \\. 498, fig. 61, 62.

Hah. On old shells, corallines, and ascidia in deep water. At Scarborough, rare, Mr Bean. Frith of Forth, Dr Coldstream. Frequent in Berwick Bay.

This equals PL pinnata in size and delicacy, but diifers from it very obviously in having opposite pinnae, which, instead of being arched, bend inwards, so as to render the general form of the coralhne con- cave on a front view ; an appearance produced by the pinnae origi- nating, not from the sides, but from the anterior face of the stem. The stem itself is straight or slightly bent, jointed, pellucid, filled with a granular fluid matter ; and, in which it diff"ers from its congeners, bearing cells, there being always one at the base and be- tween the insertion of the pinnae, and generally another on the

148

Z. HYDROIDA.

Pl-umularia.

interval between them. Be- tween the cells there is a series of minute tubular or tooth-hke cells, visil)le only with a high mag-nifier. The ovarian vesicles are produced in summer : they are stalked, shaped like a pear or vase, solitary, scattered, and originating always at the base of a polype cell. From the interme- diate cellules, particularly from the one next the polype-cell, there often grows up a small trumpet-hke tube ; and I have seen, in one specimen, all the ends of the branches terminated by four of these tubes diverg- ing in pairs. — To this very distinct and elegant species I have taken the liberty of assigning the Christian name of the lady to whom this work is indebted for nearly all its illustrations.

" O quse fontibus integris

Gaudes, apricos necte flores,

Necte meo Lamiae coronam, Pimple'i dulcis ! nil sine te mei Possunt honores." Hor. Carm. i. ode 26.

* * Stem composed of many parallel tubes. 7. P. MYRiOPHYLLUM, clustered, the stems undivided, bellied at distant intervals, pinnate ; pinncR leaning to one side ; cells shortly tubular, seated in the axil of a curved spinous process, the aperture wide and nearly even, Ellis.

Plate XIX. Fig. 4, 5.

Corallina fruticosa pennata, Petiv. Plant. Ital. tab. 2. fig. 11. Pbea-

sanfs-tail Coralline, Ellis, Corall. 14, no. 13, tab. 8, fig. a. A Ser-

tularia myriophyllum, Linn. Syst. 1309. Pall. Elench. 153. Ellis and Soland. Zoopb. 44. Berk. Syn. i. 217. Turt. Gmel. iv. 678- Turt.

Br. Faun. 213. Stew. Elera ii. 443. Bosc, Vers,iii. 109 Aglaophenia

myriophyllum, Za7Bo«r. Cor. Flex. 168. Corall. 74. Plumularia myrio- phyllum, Zam. Anim. s. Vert. ii. 124. 2de edit. ii. 159. Flem. Brit. Anim. 547. Templeton in Mag. Nat. Hist. ix. 466. Stark, Elera. ii. 440.

Risso, L'Europ. Merid. v. 312 La P. myriophylle, Blainv. Actino-

log. 477, pi. 83, fig. 4. Hah. Deep water, rare. Near Dublin, Ellis. Coast of Devon- shire, Dr Coldstream. " Found by R. Brown, Esq., on the shore at Ballycastle. In Dublin Bay," Templeton.

4

Tlumularia. Z. HYDROIDA. 149

The roots are matted together with numerous entangled fibres. Stalks 6 inches in height or more, the largest as thick as a crow-quill, yellowish-brown, straight or slightly curved, swollen at intervals on the back, and simple or once divided : they are each of them com- posed of a number of tubes bound together, as is easily seen on a transverse section, and the oblong dorsal knobs seem to be produced by a less close adhesion of the tubes at these places, " marking pro- bably the stages of growth." The branches or pinnag spring from both sides beginning about the middle of the stalk, the lower part be- ing naked, but they incline so much one way as to appear unilateral. The wide cylindrical cells are divided from each other by a joint, and are seated in the axil of a curved spinous process which projects far

enough to form a short tooth at the under side of the aperture.

When dry the stalk is twisted and more distinctly perceived to be composed of a bundle of tubes, and consequently furrowed. In each of the furrows there is a row of small holes with a raised brim as if punctures had been made by an instrument pushed from within. The holes are close- set, and regular in their size, form, and in the distances between them.

8. P. FRUTESCENS, stcm branched, the branches primate ; pinnce alternate, bifid; cells infundibidiform, leaning, rather dis- tant, the mouth plain. Ellis.

Plate XX. Fig. 2, 3.

Sertiilaria Gorgonia, Pall. Elench. 158 S. frutescens, Ellis and So-

land. Zooph. 55. pi. 6, fig. a, A. and pL 9. fig 1, 2, encrusted with a Gorgonia. Turt. Gmel. iv. 680. Turt. Brit. Faun. 214. Steiu. Elem. ii. 445. Bosc, Vers, iii. 113. Hogg's Stock. 33.— Aglaophenia fru- tescens, Lamour. Cor. Flex. 173. Corall. 76 Plumularia frutescens,

Flem. Brit. Anim. 547. Lam. Anim. s. Vert. 2de edit. ii. 166 La

P. frutesceiite, Blainv. Actinolog. 477. Hah. Found at Scarborough in Yorkshire, Ellis, — whence I have specimens from 3Ir Bean, who states that it inhabits deep water, where it grows attached to stones and shells by a fibrous base, and is very rare. Hartlepool, Durham, J. Hogg, Esq.

Polypidom between four and five inches in height, firm and woody, black or dusky-brown, varnished, irregularly branched. Stem and branches tapered, composed of many parallel twisted capillary tubes, the branches erecto-patent, spreading laterally, pinnate ; pinnsE rather close, alternate, two or three from each space between the joints, and each divided into two branches. Cells rather distant, adnate, cylin- drical widening outwards, smooth, with an entire slightly everted margin : there is a small cell in the axils of the pinnae, and a den-

150 Z. HYDROIDA. Laomedea.

tide at the base of all the cells, each of which occupies a joint. Vesi- cles scattered, small, pear-shaped, the rim of the opening plain.

10. Laomedea.* Lamouroux. Character. Polypidom rooted by a creeping jihre^ plant- like^ erect ; jointed at regular intervals^ the joints ringed, incras- sated, giving origin, alternately on opposite sides, to the shortly pedicled cells ; cells campanulate : vesicles axillary. — Polypes hydraform.

1. L. DicHOTOMA, stem filiform, branched dichotomously ;

cells alternate, campanulate, the rim even. Ellis.

Plate XXII. Fig. 1, 2. Sea-thread Coralline, Ellis, Corall. 21, no. 18, pi. 12, fig. a, A Sertu-

laiia dichotoma, Lin. Syst. 1312. Ellis and Soland. Zooph. 48. Berh.

Syn. i. 218. Turt. Gmel. iv. 682. Wern. Mem. i. 564. Turt. Brit.

Faun. 215. Stew. Elem. ii. 446. Bosc, Vers, iii. 118. Hogg's Stock.

3-3 S. longissima. Pall. Elencb. 119. Sert. volubilis. Fabric.

Faun. Groenl. 444. Laomedea dichotoma, Lamour. Cor. Flex. 207.

CoraU. 91. Risso, L'Europ. Merid. v. 314. La Laomedee dichotome,

Blainv. Actinol. 474. Campanularia dichotoma. Lam- Anim. s. Vert.

ii. 113. Flem. Brit Anim. 548. Stark, Elem. ii. 441. iJjsso, L'Europ.

Merid. v. 309- Grant in Edin. New Phil. Journ. i. 151. Grant in

Cyclop. Anat. and Phys. i. 108, fig. 30. Grant, Comp. Anat. 10, fig.

5. Johnston in Trans. Newc- Soc. ii. 255. Templeton in Mag. Nat.

Hist. ix. 469. Lister in Phil. Trans, an. 1834, 372, pi. 8, fig. 5. Hab. On old shells in deep water, common. " This is found in great abundance on the south-west coast of England, and seems most curiously contrived, from its structure, to resist the violence of the waves, allits joints bein^ furnished with springs," JEllis. Scarborough, Mr Bean. Dunstanborough Castle, Mr R. Embleton- Berwick Bay, G. J. Leith shore, Jameson. Found on the shore of Dublin Bay, &c. Templeton.

Polypidom confervoid, rooted by a creeping flexuous fibre, from four to six inches high, slender, filiform, smooth, of a blackish colout-, wavy, branched in a dichotomous or alternate manner, the branches ringed at their origins, simple or divided like the primary stem. The cells are bell-shaped, on ringed stalks, transparent and very tender, so that specimens gathered amongst the rejectamenta of the sea are mostly deprived of them. Polypes reddish. Vesicles ovate, smooth, axillary, filled with ova in spring. These are numerous, " amount- ing to twenty or thirty in each vesicle," and like the ova of zoophytes

* A*ofjiiS'ii», — the name of one of the Nereids, according to Hesiod's Theo- gony. V. 257.

Laomedea. Z. HYDROIDA. 15J

in general, clothed with cilia and moveable. Every three of them are inclosed, while in the vesicle, within a thin transparent motion- less capsule, presenting at its free extremity several stiff, straight^ diverging pointed processes, which Ellis mistook for the tentacula of a young polypus. Dr Grant.

Sir John G. Dalyell has made some singular observations on this species, which seem irreconcileable with those of Professor Grant and Cavolioi. He tells us that it rarely produces vesicles. When pre- sent they contain from 20 to 30 greyish corpuscula with a dark cen- tral nucleus. " At first, all are immature and quiescent, but motion at length commences : the corpuscula become more distinct ; sevei'al slender arms protrude from the orifice of the vesicle, which are seen in vehement action, and, after many struggles, an animated being es- capes. But this has no relation either to the planula of the Sertu- larise, or the corpusculum of the Flustra, Alcyonium, or Actinia. It might be rather associated with the Medusariai. Before ascertaining its origin, I had named it Animalculum tintinnabuluvi, from its gene- ral resemblance to a common hand-bell, for the purpose of recogni- tion. This creature is whitish, tending to transparency, about half a line in diameter ; the body is like a deep watch glass, surmounted by a crest rising from the centre, and fringed by about twenty-three tentacula pendant from the lip below. These are of muricate struc- ture, or rough, and connected to the lip by a bulb twice their own diameter. The summit of the crest unfolds occasionally into four leaves, and four organs prominent on the convexity of the body, ap- pear at its base. When free, the animal swims by jerks, or leaps through the water, or drops gently downwards ; it is invited to move by the light, and it has survived at least eight days. Then it disap- pears, at least I have not been able to pursue its history longer. No other product has ever issued from the vesicles of the Sertularia di- chotoma." Edin. New Phil. Journ. xxi. 91-2.

2. L. GENICULATA, stem zig-zag, simple or sparingly brandi- ed ; cells on annular stalks from the joints, alternate, campanu- late, the 7'im plain ; vesicles ovate. Doody.

Plate XXI. Fig. 1, 2. Corallina confervoides gelatinosa alba, gcniculis crassiusculis pellucidis,

Baii, Syn. i. 34, no. 7. Fucoides setaceum tenuissime alatiini, Ibid.

38, no. 6, pi. 2, fig. 2. Ellis, in Phil. Trans, abridg. x. 491, pi. 12, fig.

1, a, A. Knotted-thread Coralline, Ellis, Corall. 22, no. 19, pi. 12.

h. B Sertularia geniculata, Z/». Syst. 1312. Pull. Elencli. 117.

Mull. Zool. Dan. tab. 117, fig. 1-4. Ellis awA Solund. Zooi)li. 49. Berk. Syn. i. 218. Tiirt. Gmel. iv. 682. Weni. Mem. i. 564. Tint. Brit. Faun. 215. .S^ew. Elem. ii. 446. ^osc. Vers, iii. 117. Z«»(. Anim. s.

152 Z. HYDROIDA. Laomedea.

Vert. ii. 120. 2de edit. ii. 149. Hogg's Stock. 33 Laomedea geni-

culata, Lamour. Cor. Flex. 208. Corall. 91. Templeton in Mag. Nat.

Hist. ix. 466. La L. geniciilee, Blainv. Actinol. 474 Campanularia

geniculata, Flem. Brit. Anim. 548. Johnston in Trans. Newc. Soc. ii. 235. Hab. Parasitical and gregarious on sea weeds that grow near low- tide mark, especially on tlie frond of Laminaria digitata, very com- mon.

Polypidom attached by a creeping tulnilar thread, erect, about an inch in height, simple or sparingly branched, regularly zig-zag, slen- der and flexile, of a clear white colour, often tinted more or less with rose-red, and filled with a dusky granular pulp : at every flexure, the stem is divided by a single joint and incrassated, a twisted pedicle originating from the incrassated part alternately from opposite sides ; the pedicle consists of 4-6 nearly equal rings, is erecto-patent, taper- ed slightly and terminated with a bell-shaped cell, perfectly transpa- rent and entire. The vesicles are matured in spring : they originate from the incrassation of the joints at the side of the cells, and re- semble an elegant Greek vase or urn, being of an elliptical or ovate shape, with a very short tubular opening on the flattened apex. The ova are comparatively large.

The polypidom is occasionally tinted of a pink or rose-red colour, . — an accident which is not unfrequent with the Sertulariadse in ge- neral, especially with Sert. abietina and pumila. On what the colour depends has not been ascertained. Some specimens so tinted retain the colour after being dried, while others lose it. The nature of the habitat has apparently no influence on it, for I have often observed coloured and colourless specimens on the same stone or sea-weed.

f5. L. GELATINOSA, " Sill) Ordinate branches dichotomously branched ; cells on twisted footstalks^ companulate^ icith even mar- gins." Ellis.

Plate XXI. Fig. 3, 4. and Plate XXIII. Fig- 1. Corallina tiliformis ramosa pedunculis calyeulonim contortis, Ellis, Corall. pi. 38, fig. 3, and p. 23, pi. 12, fig. c, C. — Sertiilaria gelatinosa, Pall Elench. 116. *S^ew. Elem. ii. 444. jBosc, Vers. iii. 112. Fleming in

Edin. Phil. Journ. ii. 84. Flem. Phil. Zool. ii. 616. pi. 5, fig. 3

Campanularia gelatinosa, Flem. Brit. Anim. 549. Johnston in Trans.

Newc. Soc. ii. 254. Sertularia dichotoma, in part. Lister in Phil. Trans.

an. 1834, 372, 375, pi. 10, fig.^^l — Laomedea gelatinosa, Corallina, 92.

La L. gelatineuse, Blainv. Actinol, 475 — La Scrtolara dictoma, Cavol.

Pol. mar. 194, tav. 7, fig- '5 — 8.

Hab. On stones ^tween tide marks. "Very common in the

Tay above Balmerino, towards Flisk beach," Fleming. In Berwick

Bay, abundantly, G. ./,

Laomedea. Z. HYDROIDA. 153

This species, in its most perfect state, rises to the height of 8 or 10 inches. The stena is as thick as small twine, straight, opake, and composed of many tubular threads twisted together. It does not properly divide itself, but sends off branches from all sides, which are either opposite or alternate, and much ramified into diverging branch- lets, each of them marked with three or four rings at its base, and terminated with a bell-shaped polype-cell of a very thin corneous texture. A specimen of this description from Shetland, in the col- lection of my friend Dr Coldstream, is figured in Plate XXII I.

But more commonly Laom. gelatinosa is found in a much hum- bler condition, and under a guise that requires for its discrimination from Laom. geniculata, a careful examination. It occurs thus in Berwick Bay, growing gregariously on the sides and under surface of stones lying in shallow pools between tide-marks, and seemingly giving a preference to those that contain an impure or brackish water. The shoots are all connected with one another by the ra- dicle fibre which creeps in an irregular manner along the rock ; they are rarely above an inch in height, simple or sparingly branched, consisting of a single tube of a light corneous colour and texture, ringed above the origins of the long twisted filiform pedicles on which the polype-cells are raised. These cells are deeply cupped, transparent, with a wide even margin. Vesicles urn-shaped, smooth, shooting from the axils of the pedicles. They are matured during the summer months, when we find them filled with ova of a circular flat- tish form, marked with a dark speck in the centre. At first they fill not more than half of the vesicle, but by their increase in size they soon come to occupy the whole cavity, and are ultimately extruded from the top, after which the empty vesicle soon disappears. The ova while in the vesicle are ai'ranged round a central placentular column, and the lid which closes the vesicle is a mere dilatation of this column, which appears to be composed of two pieces soldei'ed together, and bulged at intervals, where perhaps the ova are more immediately af- fixed in their immature state.

The Polypes have about twenty long filiform tentacula roughened with minute tubercles placed in whorls. In their centre is the mouth, which assumes the shape sometimes of a rounded projecting tubercle, sometimes of a narrow column, and sometimes of a broad flat disk with a stricture under it simulating a neck. It leads directly to the stomachal cavity which is large and undivided, and I have occasional- ly witnessed within it currents of a fluid filled with minute granules, as has been more fully noticed by Mr Lister and Dr Fleming.

Milne-Edwards, in the belief of there being a specific difference between the zoophytes described by Pallas and Fleming, has propos-

154

Z. HYDROIDA.

Camp A NUL ARIA

ed to call the latter Campanularia Flemingii, distinguished by the cells having an even rim, whereas it is stated to be serrulated in the other. I have preferred following the judgment of Fleming, who has very carefully studied the species.

1 1. Campanularia, * Lamarck. Character. Polypidom rooted, creeping or when compound erect, the main tube filiform, continuous, giving off its peduncu- lated cells irregularly or in whorls ; pedicles ringed, usually long ; cells campanulate ; vesicles scattered, sessile. — Polypes hydra- form.

* Stem a single tube. 1. C. voLUBiLis, stem creeping, filiform ; cells on long slen- der annidar pedicles, campaniform ivith a serrated rim ; vesicles ovate, lorinkled concentrically. Ellis.

Fig. 17

ri \ \

Small climbing Coralline with bell-shaped cups, Ellis, Corall. 24, no. 21 , pi. 14, fig. a. A. Phil. Trans, xlviii. 629, pi. 22, no. 2. Phil. Trans.

abridg. x. 491, pi. 12, fig. 2, B. Sertularia volubilis, Lin. Syst. 1311.

Ellis and Soland. Zooph. 31, pi. 4, fig. e, f, E. F. copied into Kirb,/'s Bridgew. Treat, i. pi. 2, fig. 2. Berk. Syn. i. 218. Turt. Gmcl. iv. 080. Fabric. Faun. Grcenl. 444. Wern. Mem. i. 3G4. Turf. I5rit. Faun. 214. Slew. Elem. ii. 444. Bosc, Vers, iii, 112. Hof/y's Stock.

* From Campanula, a bell. 3

Campanularia. Z. HYDROIDA. 155

34, S. imiflora, Pall. Elench. 121. Ellis, in Phil. Trans. Ivii. 437,

pi. 19, fig. 9 Clytia volubilis, Lamour. Cor. Flex. 202. Corall. 88.

Campanularia volubilis,ZaHi. Anim. s. Vert. ii. 113. 2de edit. ii. 132. Flem. Brit. Anim. 348. Risso, L'Europ. merid. v. 309. Johnston in Trans

Newc. Soc. ii. 255. Templeton, in Mag. Nat. Hist. ix. 466 La

Campamilaire grimpaute, Blainv. Actinolog. 472, pi. 84, fig. 2. Ilab. Parasitical on other corallines, frequent. Brighthelrastone, on the coast of Sussex, JEllis. Frith of Forth, adhering to Flustrae and Fuci, Jameson. Berwick Bay, G. J. Found in Belfast Lough, Templeton. On specimens of Sertularia tamarisca, &c. from Scar- borough, Bean.

A minute species, and a beautiful object for the microscope. I have seen the antennae of a crab (Lithodes spinosa) so profusely invested with this zoophyte as to resemble hairy brushes. The coralline in this instance had chosen a station by which it obtained all the bene- fits of locomotion. Our figure represents a specimen which had adorned in a similar manner the remnant of a Pluraularia falcata. The stem is a capillary corneous tube which creeps and twists itself upon its support, throwing out, at alternate intervals, a long slender stalk twisted throughout or only partially, that supports a bell-shaped cup of perfect transparency and prettily serrulated round the brim. The ovarian vesicles arise from the creeping tube, are sub-pedicellate, ovate, coarsely wrinkled, and contain each several ova. Polypes with numerous slender white tentacula.

2. C. SYRiNGA, stem creeping, capillary ; cells on shorter twisted pedicles, tubulous, ivith a plain margin. Ellis.

Fig. 18.

Creeping Bell-Coralline, Ellis, Corall. 25, pi. 14, fig. h. B Sertularia

syringa, Lin. Syst. 1311. Berk. Syn. i. 218. Turl. Gmel. iv. 680.

Turt. Brit. Faun. 214. Stew. Elem. ii. 444. Bosc, Vers, iii. 113

S. volubilis, Pall. Elench. 122 S. repens, JEJWs- and Soland. Zooph.

156 Z. HYDROIDA. Campanularia.

52. Hogg's Stock. 34 Clytia syringa, Lamour. Cor. Flex. 203.

Corall. 89. Campanularia syringa, Lam. Anim. s. Vert. 113. '2de

edit. ii. 132. Flem. Brit. Anim. 548. Johnston in Trans. Newc. Soc. ii. 256. Blainv. Actinolog. 472. Hub. Parasitical on other corallines and the lesser fuci, less com- mon than the preceding.

This is only to be distinguished from C. volubilis by the aid of the microscope. The two species frequently grow intermixed, and their habit is the same, but the syringa is easily distinguished by its denser corneous structure, its cylindrical tubular cells, and the shortness of the pedicles which support them. Polypes with 8 filiform equal ten- tacula. — Pallas describes a branched variety from the coast of Corn- wall, which, however, undoubtedly belongs to C. dumosa. His words are — " Nuper ex Oceano Cornubiam alluente, ubi haec Sertularia in testaceis et Zoophytis omnibus abundat, accepi ramescentem eandem, seu vegetantem ; dum tubuli 2)lurimi proprii simul assurgentes effi- ciunt stirpes sponte erectas, stepe sesqui-pollicares, ramumque unum vel alteram exserentes, totas ab imo ad summum calyculis tubulifor- mibus, sine ordine, quaquaversum muricatae/'

* * Stem composed of many parallel tubes. 3. C. VERTiciLLATA, erects branched ; cells on verticillate pe- dicles, campanulate icith a serrulated rim. Dr Brownrigg.*

Plate XXII. Fig. 3, 4. Horse-tail Coralline with bell-shaped cups, Ellis, Corall. 23, no. 20, pi.

13, fig. a, A Sertularia verticillata, Z>znw. Syst. 1310. Pall. Elench.

115. Ellis and Soland. Zooph. 50. Berk. Syn. i. 218. Titrt. Gmel. iv.. 679. Turt. Brit. Faun. 214. Stew. Elem. ii. 444. Base, Vers,

iii, 112. Hogg's Stock. 34. Clytia verticillata, Lamour. Cor. Flex.

202. Corall. 88. Campanularia verticillata, Lam. Anim. s. Vert. ii.

113. 2de edit. ii. 131. Flem. Brit. Anim. 550. Templeton'm Mag. Nat.

Hist. ix. 466. Stark, Elem. ii. 441.- La Laomedee vertieillee, Blainv.

Actinolog. 475, pi. 84, fig. 3. Hah. " Near Whitehaven, in Cumberland," Dr Brownrigg. Near Hartlepool, Durham, not very frequent, J. Hogg, Esq. Not uncom- mon on the coast at Scarborough, adhering to shells, &c. Mr Bean. Cullercoats, Northumberland, Mr Joshua Alder.

* Dr William Browmrigg, born at High Close Hall, Cumberland, March 24, 1711 ; graduated M. D- at Leyden in 1737 ; elected F. R. S. in 1742 ; in 1748 published his valuable work on the art of making common salt ; received the Copley medal for the year 1765 ; continued to prosecute with zeal his chemical and philosophical experiments, and to eiijoy his literary taste, until the period of his death, which took place at Ormathwaite, January 6, 1800, aged 88 years. For an able biographical account of this learned and excellent physician, see the Annals of Philosophy, Vol. x. p. 321, he.

Campanulakia. Z. HYDROIDA. 157

Polypitloiu adhering; by creeping- tubulous fibres, erect, iiTegularly branched, the stem and branches composed of many closely applied parallel tubes ; branches erect or erecto-patent, cylindrical, straight, hirsute from the capillary pedicles of the cells which originate in whorls at stated intervals : the pedicles are ringed at top and bottom but generally smooth about the middle, patent, simple : the cell itself campanulate, thin and transparent with a serrated brim. Vesicles scattered, arising- from the branches, solitary, very shortly stalked, oval, smooth, with a narrow aperture.

4. C. ? DUMOSA, erector climbing, ii^regularly branched, hirsute with the cells, lohich are long, tubular, patent, almost sessile, the aperture entire. Rev. Dr Fleminor.

PLATEXXIII.Fig-. 2— 5.

Coralliiiii astaci corniculorum semiili, Petiv. Plant. Ital. pi. 2, fig. 10 —

Sertularla dumosa, Fleming in Edin. Phil. Jouni. ii, 83 Tubularia

tubifera, Johnston in Edin. Phil. Journ. xiii. 222, pi. 3, fig. 2, 3 La-

fea cornuta, Lamour. Soland. ^ooph. 5, pi. 65, fig. 12-14 Campanu-

laria dumosa, Flem- Brit. Anini. 548. Johnston in Trans. Newc Soc ii. 254. pi. 11, fig. 1 La Laomedee touffue, Blainv. Actinol. 474.

Hah. On rocks, shell-fish, and other corallines, in deep water. On the shores of Devonshire, Montagu. At Newhaven in the Frith of Forth, at Aberbrothick and in Zetland, Fleming. Berwick Bay, ver}^ common, G. J.

There are two varieties of this species : the first is from 2 to 4 inches in height, bushy, irregularly branched, the branches straight, square, slightly tapered upwards, and formed of several parallel tubes ; (Fig. 4.) the second is a single thread-like tube which climbs up the stalks of other flexible corallines, giving off on all sides its long spreading- trumpet-shaped cells, which are not unlike those of C. syringa, but are to be distinguished by their thicker and much more horny texture, and by being almost or altogether sessile (Fig. 2, 3.) Small specimens of the first variety are very common on some sorts of crabs, but the larger specimens have their roots or base almost invariably immersed in the substance of a sponge, the Halichondria panicea or papillaris. Neither the vesicles nor polypes have been observed, and there is something in the habit, and in the form of the cells, which renders it very doubtful whether this species belongs to this order.

This appears to be the proper place to notice two doubtful zoo- phytes which have been I'eferred to the genus

158 Z. HYDROIDA. Cymodocea.

Cymodocea,* Lamouroux. Character. " Plant-like ; cells cylindrical, varying in length, Jiliform, alternate or opposite ; stem Jistular, marked loith rings beloiv, plain above, and without interior division."

1. C. SIMPLEX, stems simple, slightly undulated, tivig-like ;

cells long and filiform, alternate. Dawson Turner.-f-

Cymodocea simplex, Lamour. Cor. Flex. 216, pi. 7, fig. 2. Corallina, 95,

pi. 7, fig. 2 La Cymodocee simple, Blainv- Actinolog. 487. pi. 81,

fig- 4.

Hab. The sea near Yarmoiith, and in Ireland, Turner. Height nearly three inches : colour a yellow-fawn.

2. C. coMATA, stems straight, cylindrical, almost simple ;

branchlets capillary, whorled, numerous, fiexuous, jointed and

ceiliferous. Dr Leach.J

Cymodocea comata, Lamour. Ellis and Soland. Zooph. 15, pi. 67, fig- 12, 13. Flem. Brit. Anim. 551. La C. chevelue, Blainv. Actino- log. 487.

Hab. Coast of Devonshire, Leach.

Height about one decimetre : colour yellowish. At each joint of the branchlets there is a short cell ringed at its base, and almost in- visible to the naked eye.

I have seen no authentic specimen of either species, the above descriptions being translated from the works of Lamouroux. He says that Cymodocea has the closest relations with Tubularia, from which, however, it differs in the position of the polype-cells which are placed, not at the top of the branches, but upon these branches or upon their divisions. From this circumstance La- mouroux classes the genus amongst the Sertulariadse, to which alli- ance the absence of ovarian vesicles seems opposed, nor can we hope to locate the genus with any certainty until the polypes have been discovered. The very existence of the genus has in fact been ques-

* The name of one of the sea-nymphs into which the ships of iEneas were changed by Cybele.

f D. Turner, Esq. of Yarmouth, F. L. S. : — very eminent for his knowledge of cryi^togamic botany, and for his skill in antiquities. He is the author of a beautiful work on the Fuci. The genus Dawsonia of Robert Brown is a just tribute to his merit.

\ William Elford Leach — a naturalist of most indomitable enthusiasm and very extraordinary acquirements. He died in Italy in 1836, of cholera. " We may say, with respect to the extent and effect of his zoological labours, — Nihil non tetigit, et omnia quae tetigit ornavit." — Kirhy.

Cymodocea. Z. HYDROIDA. 159

tioned. IMr J. E. (Jray, a high authority in matters of this kind, says, " the Cymodocea) appear to be only Sertularite which liave lost their cells," (Synop. of Brit. Mus. p. 75) ; and Blainville makes the same assertion in reference to the above species.* Dr Fleming is of opinion that C. simplex has been established from an individual of Campanularia dichotoma in a depauperated state ; (Brit. Anim. 548,) while again IMr Hogg informs me that he is almost satisfied that this Cymodocea is Plumularia pinnata with its pinnae rubbed off by the waves or tide on the beach ; and the specimens he has sent me in confirmation of this supposition are certainly very exact to Lamou- roux's figure, nat. size, — for it must be observed that his magnified fi- gure represents the polypidom as unjointed or continuous, whereas it is regularly jointed both in the Campanularia and Plumularia. But I make this remark not to invalidate the opinions either of Dr Flem- ing or Mr Hogg, for that of the latter I am disposed to adopt ; but it gives me an opportunity of warning the student against an implicit reliance on the figures of Lamouroux, which we are assured by Blain- ville, who has compared them with the specimens from which they were made, are in many instances very erroneous.

* Milne-Edwards also adopts this view. Lam. Anim. s. Vert 2de edit- ii. 157.

" All the works of the Lord are exceeding good : and none may say, What is

this ? Wherefore is that ? for at time convenient they shall all be sought out

All the works of the Lord are good : So that a man cannot say, This is worse than that ; for in time they shall all be well approved." — Ecclesiasticus.

BRITISH ZOOPHYTES.

PART III.

ZoOPHYTA ASTEROIDA.

Fii(. li).

GORGONIA FlABELLUJI.

" — — — — — all the firmament

" Was throng'd with constellations, and the ^v;\

" Strown with their images " — James Montgomery.

" Nicostratus in ^lian, finding a curious piece of wood, and being wondered at by one, and asked what pleasure he could take to stand as he did still gaz- ing on the picture ? answered, Hadst thou mine eyes, my friend, thou wouldst not wonder, but rather be ravished as I am at the inimitable art of this rare and admirable piece- I am sure no picture can express so much wonder and excel- lency as the smallest insect : but we want Nicostratus his eyes to behold them.

" And the praise of God's wisdom and power lies asleep and dead in every creature, until man actuate and enliven it. I cannot, therefore, altogether con- ceive it unworthy of the greatest mortals to contemplate the miracles of nature, and that as they are more visible in the smallest and almost contemptible crea- tures, for there most lively do they express the infinite power and wisdom of the great Creator, and erect and draw the minds of the most intelligent to the first and prime Cause of all things, teaching them as the power, so the presence of the Deity in the smallest insects. " Samuel Purchas.

ZOOPHYTA BRITANNICA.

ORDER II. Z. ASTEROIDA.

Character.

Polypes compound, the mouth encircled icith 8 pectinate tenta- cida ; stomach membranous ivith dependant vasculiform appen- dages ; intestine 0 ; anus 0 ; reproductive gemmules produced in- teriorly. Polype-mass variable in form, free or permanent- ly attached, carnose, generally strengthened with a horny or cal- careous axis enveloped ivith the gelatinous or creto-gelatinous crust in which the polype-cells are immersed, and which open on the surface in a starred fashion with 8 rays.

Observations. On a cursory view the Polypidoms of the three families em- braced in this order appear very dissimilar, and accordingly, by many recent authors, they have been scattered over the class, and placed widely asunder. The affinity between them, how- ever, is generally acknowledged, and had been distinctly per- ceived by some of the earliest zoophytologists. Thus Bohadsch found so much in common between the typical Pennatulae and a species of Alcyonium, that he has not hesitated to describe them as members of the same genus ; and although the more systematic character of Pallas prevented him falling into this error, — if error it can indeed be called, — he did not the less recognize the relationship between the genera or families.* Pal-

" " Pennatulae Alcyoniis specierum gradatione ita propinquse sunt et tamen simul structura, habitu, vitseque sensitivse gi-adu discrepant, ut exempliini majoris siraul affinitatis et discordantise inter duo genera in rerum natura vix dari exis- timem. Certo respectu Pennatulae ad Alcyonia sunt, quod Hydraead Sertularias." Elench. p. 362 — In' relation to this paragraph consult also p. 370, 343, 162, 191:— and Misc. Zool. p. 177.

164 ZOOPHYTA ASTEHOIDA.

las also tells us that his Pennatula cynomorium ditfers from the Alcyonium only in this, that the former is a moveable, and the latter a fixed polypidom ; and he saw with equal clearness, the connection which exists between these genera and the shrub- like Gorgonia. Of the Pennatula mirabilis he had entertained doubts whether it was not rather a species of Gorgonia until he perceived that the stem was attenuated at each end and free ; and of the Sea- Pens generally, Ellis remarks, that they are " a genus of zoophytes not far removed from the Gorgonias, on ac- count of their polype mouths, as well as having a bone in the inside, and flesh without." On the other hand the Gorgoniae, says Pallas, seem, with the exception of their horny skeleton, to be nearly similar in structure to the Alcyonia ; but as there are species of Gorgonia which are suberose internally and almost of a uniform medullary consistence, even this mark of distinction fails to separate the tribes, and we have little left to guide us in arranging these osculant species excepting their external habit, or, if we may so express ourselves, their physiognomy. Gorgonia Briareus has been described by some authors as an Alcyonium ; and Pallas would have enumerated the Gorgonia radicata in the same genus, had not its gorgon-like habit interfered. I am satis- fied that no zoophytologist can examine Ellis's figure and de- scription of Gorgonia suberosa without being convinced that it pertains rather to the congenerous family, or holds at least very debateabie ground between them.

The names which the fishermen have conferred on the poly- pidoms of this order will convey to the student a better idea of their general appearances than any laboured description. The Pennatuhe in their language are Sea- Pens ; the Virgularige are Sea- Rushes ; Sea- Paps, Deadman's hand or Dead-man's toes, if not agreeable, are yet expressive names for the Alcyonia ; and the Gorgoniae are Sea-shrubs when they branch away irre- gularly, but when the branches inosculate and form a sort of net, they become Sea- Fans, which some naturalist, of more than our usual fancy, has appropriated to the use of Venus — Fla- bellnm Veneris.*

* Kay has especially culleil attention to the fan-like growth of submarine bodies. — "That the motion of the water descends- to a good depth, I prove from those plants that grow deepest in the sea, because they all generally grow flat in man- ner of a fan, and not with branches on all sides like trees ; which is so contriv-

ZOOPIIYTA ASTEROIDA. 165

In every polypidom of this order there are three parts which require notice, — the polypes, the fibro-fleshy calcareous crust in which they are placed, and the internal axis. The con- nection between these parts is indissoluble, and although we may treat of them separately, and as if they were some- what independent, yet we must guard against the entertain- ment of any such opinion. * It was once indeed a debated question whether each polypidom might not rightly be con- sidered a mere aggregation of separate animalcules, but all that we know of their habits and structure goes to prove the contrary, so that no one probably now disputes that the polypidom with its polypes constitute but one body, the latter being in the place of as many mouths and stomachs scattered over the surface. The whole mass, with the exception at most of the axis in those which possess a stony or horny one, is living and organized, re- ceiving the material of its nourishment and growth from the food captured and digested by the polypes ; and as they have not only an organical union with the irritable flesh in which they are immersed, but are many of them more intimately associated to- gether by means of canals and intestines, so they participate in every benefit and every evil. When, therefore, one pinna of a Sea- Pen is lacerated or cut away, the remaining pinna? gradu- ally shrink, the polypes withdraw, and the whole body con- tracts in every dimension ; or if a portion of the Alcyonium be subjected to irritation, the gradual collapse and contraction of the polypidom renders it obvious that the irritation has been communicated and felt through the entire mass.-f- On the con- ed by the providence of nature, for that the edges of them do in that posture with most ease cut the water flowing to and fro ; and should the flat side be ob- jected to the stream, it would soon be turned edge-wise by the force of it, be- cause in that site it doth least resist the motion of the water : whereas did the branches of these plants grow round, they would be thrown backward and for- ward every tide. Nay, not only the herbaceous and woody submarine plants, but also the lithophyta themselves afl^ect this manner of growing, as I have ob- served in various kinds of corals and pori." — The Wisdom of God in the Crea- tion, p. 77.

• Tiedemann has inadvertently asserted that the polypes '• are able to leave the crust and return to it." Comp. Phy. 306.

}• " Unknown to sev the pregnant oyster swells, And coral-insects build t/ieir radiate cells ; Parturient Sires caress their infant train, And heaven-born Storge weaves the social chain ■

166 ZOOPHYTA ASTEROIDA.

trary, when at rest and undisturbed, the polypes protrude their tentacula and a portion of the body, and, imbibing the circum- fluent water, this percolates into the interior through numerous anastomosing canals, and distends the polypidom so much that it will more than double or treble its former size. In this re- spect the Zoophyta asteroida show an affinity to the Helianthoida, and differ from the hydraform and more especially from the as- cidian orders.

The axis of the Alcyonidse is imperfect, but exists neverthe- less in the form of calcareous or siliceous spicula diffused through the gelatinous interior, or more or less densely clustered at the centre; and the appearance of these spicula is such that we are almost tempted to believe they may possibly be the products of crystallization rather than of any regular secretion.* It might not be difficult, but it is beyond my province, to trace the gra- dual increase and consolidation of these spicula through many intermediate species to the horny flexible axis of Gorgonia, where it has become such an efficient support to the whole soft envelope as to claim not improperly the name of its skeleton ; thence to the stony axis of the coral ; and having there reached its maximum of developement, I might, on the other hand, have marked its progress towards degeneration until it became again only a partial support, such as we find it in the naked middle portion of the Pennatulidae, more especially in some of the fo- reign and less typical species of that family.

According to Lamarck, this axis, under all its modifications, is inorganic, containing neither vessels nor any portion of the body of the polypes, but formed of matter excreted by them, and afterwards thickened, solidified and depurated by af- finity.-f- Although this is rather, on Lamarck's part, the de-

Successive births her tender cares combine, And soft affections live along the line."

DarwiiVs Temp, of Nature, canto ii. * They may be compared with the Raphides found in the intercellular pas- sages of certain monocotyledonous plants. See Lindley's Introd. to Botany,

p. 29 Mr Children found in the ashes of a piece of the axis of Gorgonia

Flabellum, a distinct trace of pure silica, sufficient to form a globule before the

blow-pipe Ann. of Philosophy, New Series, Vol. ix. p. 43).

t " L'obscrvation constate que I'axe central de ccs polypiers, quoiqu' offrant quelquefois dcs couches concentriqurs, ne fut jamais organise, n'a contenu ni vaisseaux quelconques, ni aucune portion du corps dcs polypes ; qu'il est le rcsultat dc matieres excretees par ces polj'pes, matieres qui se sont epaissies,

ZOOPHYTA ASTEROIDA. 167

duction of theory than of observation, yet the opinion is in the main correct, and in correspondency with what had been long previously maintained by Ellis. In the spicula of Alcyonidae certainly, we can find no traces of organism, and they lie seem- ingly unconnected with the adjacent parts. The axis of Pen- natula is a solid bone formed of laminae laid over each other, softer and cartilaginous at each extremitv where it seems to be organically connected with the soft surrounding flesh : it is evi- dently secreted, and deposited successively in layers, from the inner surface of a thin pellucid membrane which Bohadsch has described as investing it in the manner of a periosteum,* and probably is endowed with that low degree of vitality which pre- serves the horns, hairs and feathers of the higher animals in that elastic and fresh condition which they have only when in connection with living parts. The horny axis of Gorgon ia, notwithstanding some observations of Ellis which apparently tend to a different conclusion,-}- is not more distinctly organized, and is doubtless formed in the same manner as the axis of Pen- natula, for it is also of a lamellated structure, and, according to Lamouroux, is invested with a similar periosteum. % A cross section of the stem or of a principal branch will show the layers to be disposed concentrically round a central medulla, the layers

coiidensees, epurees par I'affinite, reunies, juxta-posees successivement, et ont forme, par leur reunion, I'axe central et longitudinal dont il s'agit. Aussi cet axe est-il d'une substance continue, non poreuse." — Anim. s. Vert. V. ii. p. 294. See also p. 78—80 ; and p. 311.

• " Totum OS membrana tenuis, lutescens, pellucida cingit, atque in utroque extremo in ligamentum contorquetur, quod ex una parte in apice trunci pinnati, ex altera vero in apice trunci nudi in.seritur." — De Anim. mar. p. 104. See also Corall. p. 214,218,224.

f " Proceeding thus far, I was led on to observe, what kind of communica- tion there was between the suckers (or polypes) and the bone of the animal ; for this end I examined several specimens, both dry, as well as those that were preserved in spirits, with good magnifying glasses, and could distinctly trace an infinite number of minute winding canals, that lead from the suckers through the flesh into those parallel longitudinal tubes, which closely surround the bone or solid part on all sides ; perhaps these may not improperly be called the peri- osteum ; for all along that side of those tubes by which they adhere to the bony part, I could discover the pores very plainly from whence the juices flow, that supply it with proper materials to answer this great end." — Soland. Zooph. 69.

\ " L'ecorce des Gorgoniees ne se lie pas immediatement a I'axe, elle en est separee par une membrane d'une nature particuliere, si mince dans Ic genre Horgonia, qu'il est tres-difficilc de I'apcrrevoir ; elle est plus apparentc dans les Plexaures et les Eunicees." — Polyp Corall. Flex. p. 391.

168

ZOOPHYTA ASTEROIDA.

more or less compactly pressed according to the nature of the spe- cies. (Fio-. 21.) The whole section presents a certain resemblance to a similar section of a dicotyledonous tree : (Fig. 20.) the me- dulla in position and outward appearance is a pith ; the horny axis is the wood ; and the fleshy crust has been denominated the bark;* — nor perhaps could fault be found with this language, since it is sufficiently illustrative, had it not been the mother of some very erroneous notions, and a great means of their propa- gation and continuance. Thus Linnaeus, in his definition of Gorgonia, calls the axis a vegetating stem ; and as if this was not sufficiently explicit, we find Pallas entering into detail and telling us that the concentric circles are produced by successive transmutations of the fleshy crust, in the same manner that the circles of the wood of trees are formed by transformations of the inner layers of the bark.f And this opinion, if we may judge from their language, has been adopted by many, and even re- cent, authors, though Ellis had previous to its promulgation:}:, Fig. 20. Fig. 21.

and also shortly afterwards, demonstrated that there was not on- ly no real resemblance, but such remarkable differences as rendered the hypothesis altogether untenable. § The pith of

* Lin. Syst. 1289.

f Elcneli, p. 162. He seems, however, to have had his suspicions that the theory was questionahle, for he adds — " Qiianquam diversissima corticis natura, ejusdemque facilis a ligno separatio, siiggerere possent : hujus strata potius ex depoi-ito intiis succo fieri, aut lignum, prout ossa animalium sanguineorum intra periosteum, generari, augeri, durescere."'

t Coral. 65. Lin. Corresp.. i. 225. Phil. Trans, (an. 1776) abridg. xiii. 721.

§ What then could induce Blumenbach, so late as in 1825, to write thus?— " The stems appear to be reallt/ vegetables (the woody nature of which in the larger ones cnnnot be mistaken) incrusled with corals." — Man. of Nat. Hist. Trans, p. '271-

ZOOPHYTA ASTEROIDA. 169

the Gorgonia is not continued, as in the tree, from the trunk through the branches, but is interrupted at their origins by se- veral intervening hxyers of fibres, so tliat they are rather, as it were, inserted upon the stem than propagations of it ; the axis possesses none of that curious complexity of structure, — of fibres, of sap and air vessels and utricular cells, — which renders the wood so beautiful an object under the microscope ; and lastly there is between the bark and the crust of the zoophyte nothing but contrasts and discrepancies.*

The axis of a Gorgonia, at least of our native species, resem- bles a tree in this, that the stem always bears a certain propor- tion in thickness to the size of the polypidom, being slender in the small, and thicker in the larger specimens : it tapers from the rock or dilated base, and becoming gradually more gracile and attenuated, disappears at the extreme points of the branch- es. It is covered throughout with the fleshy which is the same in structure at all points, but thicker and more loaded with po- lypes towards the ends of the branches than on the stem or near their base, whence the former generally assume a cylindri- cal form. This flesh when dry is earthy and friable, a consi- derable proportion of carbonate of lime entering into its compo- sition ; but in a recent state it is soft and fleshy, and excavated with numerous cells for the lodgement of the polypes. When a portion of a branch is macerated in a weak acid, the lime is entirely removed, but the branch retains its original size and figure, and shows the frame-work to be an irregular close tex- ture of corneous fibres, the interstices of which had been pro- bably filled in part with a gelatinous fluid. And this is much the same structure that we find in the Alcvonium. The skin is coriaceous, strengthened with calcareous particles, but the in- terior off"ers a fibrous net-work containing a transparent jelly in the squares, and permeated with a certain number of longitu- dinal cartilaginous tubes. The soft part of Pennatula seems more uniformly fleshy or gelatinous, and its polypes are placed only on certain wings or appendages of the polypidom, but the skin is also coriaceous, and has moreover in its substance a great number of calcareous spicula placed parallel to one another, and which must greatly add to its consistency and strength.

* Ellis and Soland. Zoophytes, 76 — 70.

170 ZOOPHYTA ASTEROIDA.

The polypes are placed in this external fleshy crust, which, indeed, is but a continuation of their tunic, and serves as a connecting medium to the whole assemblage. Their position in it is marked by an orifice on the surface distinguished by its being cut into eight rays in a starred fashion, and which open when the superior portion of the body is forced outwards. * This exsertile portion, in a state of expansion, resembles a cy- lindrical bladder or nipple crowned with a fringe formed by the eight short thick pectinated tentacula which encircle the mouth. (Plate xxvi. Fig. 1.) Under this orifice we perceive the stomach, readily distinguished through the transparent parietes by its opacity, occupying the centre of the cylinder, and itself of a cylindrical figure. The space between it and the outer envelopes is divided into eight equal compartments or cells by as many thin ligamentous septa, which, originat- ing in the labial rim, between the bases of the tentacula, de- scend through the cylinder, attached on the one side to the inner tunic of the body, and on the other to the stomach, which is by this means suspended and retained in its position. The canals or cells formed by these septa communicate freely with the tubulous tentacula above ; and they have a still wider com- munication with the abdominal cavity underneath the stomach, into which we may observe the septa are also continued for a certain way, adhering still to the tunic, but free on their inner edges, for now instead of septa, they form only the same num- ber of plaits of more or less prominence and width. Attached to them, and indeed forming a part of them, there are an equal number of twisted somewhat glandular filaments, which, origi- nating round a small aperture in the base of the stomach, appear to be suspended in the cavity, gradually losing them- selves in its depth. By most authors these have been mis- taken for ovaries, -f- but though this assignation of function to

• See on this part of zoophytology Milne- Edwards Memoires " sur les Alcy- ons" in Ann. des Sc Nat part. Zool. iv. p. 333, &c. an. 1835 : and in the 2de edit, of Lam. Anim. s. Vert. ii. p. 465.

f Cuvier, Reg. Anim. iii. p. 309, 310, 319. Lamarck gives us Savigny's opinion in the following passage : " Les huit intestins d'un Polype semblent de deux sortes, car ils ne se ressemblent pas tou.s par la forme, ni vraisemhlable- ment par les fonctions. Deux d'entre eux descendent distinctementj usque an fond du corps du Polvpe, et n'arrivent a aucun ovaire. Les six autres, plus

3

ZOOPHYTA ASTEROIDA. 171

them is easily proved to be erroneous, their true office remains conjectural. Milne-Edwards says they have great analogy with the biliary vessels of insects ; and they probably secrete some fluid subservient to digestion and to the more complete assimila- tion of the food.

As already remarked the protrusile portion of the polype is very delicate, the internal viscera being as it were enclosed in a serous bladder so transparent as to permit a view of their dis- position. This envelope is itself, however, composed of two very thin membranes in intimate union : at the base of the body the outer of these assumes a considerable thickness, and in coalescing with that of the adjacent polypes, constitutes the common cortical portion into which each animalcule retreats at will by a process of invagination, which we have had occasion al- ready to compare to that by which a snail shortens its horns. (PI. xxvi. Fig.2.) In the greater number of the Asteroida this common portion secretes carbonate of lime, which is deposited in the meshes of its tissue either in granules or in crystalline spicula, and im- parts more or less of consistency to the whole. The inner tunic on the contrary continues unaltered, and prolonged within the polypiferous mass, it lines the cell, the abdominal cavity, and the longitudinal canals which permeate the mass, as well as the very tine tubular net-work with which the spaces between these ca- nals isoccupied, (Fig. 5.) for Milne- Ed wards has shewn that there is a free communication between these parts through the medium of numerous minute apertures perforated in the sides of the ab- dominal cavity. * It is probably in this tenuous inner tunic that the buds or gemmae by whose increase and evolution the polype- mass is enlarged are generated, the shape and size of the mass depending upon the manner, or pre-ordained fashion, in which the buds are evolved, for in some, as in Pennatula, determinate spots only have the appropriated organization ; while in others, as in Alcyonium, the generative faculty appears to be undefined and diffused. These buds are produced in the net -work of the crust ; while the gemmules or ova by which the species is pro- varies dans leur forme, selon les genres, paraissent s'arreter a. six grappes de gemmules oviformcs qui imitcnt six ovaires." — Aiiim. s. Vert. ii. p. 4"5 — 7; 417.

♦ Lam. Anim. s. Vert. ii. 46.3. 2de edit.

172 ZOOPHYTA ASTEROIDA.

pagated are the peculiar products of the Hning of the abdominal cavity. The ova sometimes originate in its lamellae, sometimes from the interspaces, and in other cases from the walls of the permeating canals. In Pennatula we first detect them between the membranes of the polypiferous pinnae ; in Alcyonium in the cartilaginous canals which are traced through the polype-mass, or in the abdominal sac sprouting from the plaits ; and in Gorgo- nia, Cavolini informs us, they germinate in eight distinct " ova- ria at the base of each polypus." They first appear like a minute smooth wart which gradually rises up from the surface, enlarging itself at the same time, and when a certain size has been attained, the wart becomes constricted at its base, then shortly pedicelled, and at lastit separates afree egg by the absorp- tion ofthis retaining neckor umbilical cord. (Plate xxvi. Fig. 6.) The eggs now at liberty to move, gradually approach the base of the stomach, which, as already mentioned, is perforated with an opening that can be made wider or closed by means of its sphincter muscle. After several approaches and as many repul- sions, the aperture at length allows the egg to pass through into the stomach, whence it is ejected through the mouth into the open sea. Professors Grant and Milne-Edwards have witnessed this process in the Alcyonia, and the former also in the Penna- tula and Virgularia ; but in the Gorgonia, according to Cavo- lini, the ova pass upwards " through eight small oviducts," and are discharged, by as many apertures, " between the bases of the e\a\\i tentacula." *

The structure of the ova has been well described by Cavolini, and more especially by Professor Grant. Before their detach- ment they seem, in general, to be white, but when mature they are almost always vividly coloured, globular, and apparently smooth, but clothed, as the microscope shews, with short ciliae, which by their vibration cause them to move to and fro as if they were actuated by volition. They are membranous capsules filled with a gelatinous matter composed of very minute transpa- rent globules similar to those which compose almost all the soft parts of animals, or like the sporules of the lower cryptogamic plants. The investing capsule is soft and irritable, for during their motions the ova are seen frequently to contract themselves

' Edin. Now I'hil. Jouiii. i. 15-2.

ZOOPMYTA ASTKROIDA. 173

and alter their form. " When placed under the microscope," says Professor Grant,* " and viewed by transmitted light, they appeared as opaque spheres surrounded with a thin transparent margin, which increased in thickness when the ova began to grow, and such of the ova as lay in contact united and grew as one ovum. A rapid current in the water immediately around each ovum, drawing along with it all loose particles and floating animalcules, was distinctly seen flowing with an equal velocity as in other ci- liated ova, and a zone of very minute vibrating ciliae was per- ceptible, surrounding the transparent margin of all the ova. The progressive motion of the ova, always in a direction contrary to that of the current created by their cilise, was very obvious, though less rapid than in any other zoophyte in which I have observed the same remarkable phenomenon. The specimen suspended in a glass jar filled with pure sea- water I now brought so close to the transparent side of the vessel, that I could ex- amine through it, with the assistance of a powerful lens, and without disturbing the animal, the motions and progress of the groups of ova passing through the colourless bodies of the poly- pi. To the naked eye at first sight all appeared motionless. The deep vermilion hue of the small round ova, and the colour- less transparency of the outer covering of the polypi, formed a beautiful contrast with the pure white colour of the delicate longitudinal folds, the central open canal, and the slender fila- ments which wind down from its sides towards the clusters of white ova at the base ; but the living phenomena discovered within were even more admirable than the beautiful contrast of colours, the elegant forms, and the exquisite structure of all the parts. When observed with a lens the ova were seen to be in constant motion, and quite free within the bodies of the polypi. They moved themselves backwards and forwards, and frequent- ly contracted their sides, as if irritated or capable of feeling. I could observe none passing upwards between the stomach and the sides of the polypi. They never assumed the appearance of a string of beads inclosed in a narrow shut curved tube, as represented by Spix, but swam freely in the water which dis- tended the polypi, as figured by Ellis. Their motions in the

* Dr Grant's observations, quoted in tlif text, were made on Alcyonium di- gitatum, but the generalities may be safely applied to the other families, agree- ing as they do with the observations of Cavolini on Gorgonia.

174 ZOOPHYTA A STEROID A.

polypi, though circumscribed, were so incessant, that by watch- ing attentively I could observe them with the naked eye, and they became more conspicuous as the ova advanced to the open base of the stomach. From their restlessness, as they approach- ed that last passage which separates them from the sea, they seemed to feel the impulse of a new element, which they were impatient to enjoy, and by following the direction of that im- pulse they appeared to find their way into the lower open extre- mity of the stomach, w^ithout any organic arrangement to lead them into that narrow canal. In their passage through the sto- mach, which was effected very slowly, the spontaneous motions of the ova were arrested, unless some imperceptible action of their ciliae, or some contractions of their surface, might tend to irritate the sides of that canal, and thus direct or hasten their escape."

The native species referable to the Order are not well ascer- tained. They are apparently few in number, but belong to three distinct families.

Family I. PENNATULID.E.

Polype-mass free, pennated, carnous, the skin spicuUferous, the axis hony, simple, continuous : Polypes arranged along the margin of the pinna.

12. Pennatula. Polype-mass plumous.

13. ViRGULARiA. Polype-mass linear-elongate.

Family II. GORGONIADiE. Polype-mass fixed, arborescent, the axis covered with a thick cre- taceo-gelatinous celluliferous crust : Polypes scattered over the whole surface.

14. GoRGONiA. Polype-mass arborescent with a horny continu- ous flexible axis: " cells for the polypi sessile."

Family III. ALCYONIDiE.

Polype-mass fixed, coriaceous or somewhat carnous, without any distinct axis hut strengthened by variously disposed calcareous or siliceous spicula : polype-cells subcutaneous, scattered over the sur- face.

15. Alcyonium. Polypes scattered over the whole surface : the spicula calcareous.

16. Cydonium. Polype-mass tuberous : the spicula siliceous.

Fig. 2'2.

FAMILY IV. PENNATULID^.

12. Pennatula,* Linnaeus. Character. Polype-mass free^ plumous^ the shaft suhcylin- dricalf nahedbeneath, pennated above ; piniue two-ranked^ spread- ing, flattened^ and poly piferous along the upper margin.

\. P. phosphorea, purplish-red, the base of the smooth stalk pale ; rachis roughened with close set papilla and furrowed down the middle ; pinnce close ; polype-cells uniserial, tubular, with spinous apertures. Sir R. Sibbald.

Vignette, Fig. 22.

' Formed from Penna, a quill — which the species so remarkably resemble that we may say in the words of Lamarck — " II semble, en effet, que la nature, en formant ce corps animal compose, ait voulu copier la forme exterieure d'une plume d'oiseau." — Anim. s. Vert. ii. 425.

176 Z. ASTEROIDA. Pennatula.

Penna niarina, Sib. Scot. ii. lib- teit. 28 P. rubra, Bohad. Anim.

Mar. 101, pi. 8. lig. 1-G Pennatula pLospliorea. Lin. Syst. 1332.

Ellis in PhU. Trans, liii. 420, pi. 19- fig. 1-5. Mull Zool. Dan.

prod. 255, no. 3075. Turi. Gmel. iv- 688. Wern. Mem. i. 565.

Tint. Brit. Faun. 217- Stew. Elem. ii. 450. Blumenb. Man. 274. Lam.

Anim. s. Vert. ii. 426. 2de edit. ii. 643. Citv. Reg. Anim. iii. 318.

Bosc, Vers, iii. 62, pi. 28, fig. 3, 4. (pessima) Flem. Brit. Anim. 507.

Stark, Elem. ii. 420. Johnston in Trans. Newc. Soc. ii. 248, pi. 7-

Roget, Bridgew. Treat, i. 174, fig. 71, 72. (bad.) P. rubra, Pall.

Eleneh. 368 P. Britannica, Ellis and Suland. Zoopli. 61. La

Pennatule luisante, Blainv. Actinolog. 517. Hab. Deep water. " Jt is found in great plenty sticking- to the baits on the tishermen's lines, ronnd the coasts of this kingdom; es- pecially when thty make use of muscles to bait their hooks. Great numbers have been taken on the coast of Scotland, especially near Aberdeen," Ellis. Frith of Forth. Jameson. Coast of Berwick- shire, abundant, G. J

Our fishermen call this zoophyte the Cock's-comh, a name which is not unapt, but less expressive of its general form than that of Sea- pen conferred by naturalists. It is from two to four inches in length, and of a uniform purplish-red colour, except at the tip or base of the stalk, where it is pale orange-yellow. The skin is thickish, very tough, and of curious structure, being composed of minute crystalline cylinders, densely arranged in straight lines, and held together by a firm gelatinous matter or membrane. These cylinders are about six times their diameter in length, straight and even, or sometimes slightly curved and bulged, closely compacted yet distinct, and of a red colour, for the colour of the zoophyte is derived from them, and they are accordingly less numerous where the purple is faint or de- fective. They are apparently inorganic and calcareous, being dis- solved, with effervescence, in the mineral acids.* Their form and ar- rangement is the same in every part of the skin ; and the papillae on the back of the rachis, as well as the polype-cells, are constructed of them, but none can be detected in the subcutaneous uncoloured ge- latinous flesh.

The stalk is hollow in the centime, and contains a long slender bone, which is white, smooth, square, and tapered at each extremity

* Dr Coldstream, of Leith, on wbose observations I place a greater reliance tban on my own, writes me tbus — " The spicula of the Pennatula appear to me to be solid. I have examined them with high powers, after having exposed them to a high temperature, and have not been able to see any evidence of a cavity within ; — whether viewed with reflected or transmitted light they seemed to be opaque. When connected with the body of the animal, they certainly seem to be red, but a slight degree of heat is sufficient to bleach them."

4

Pknnatula. Z. ASTEROIDA. 177

to a fine point. It seems intended to stiffen the polypidom, but it does not extend the whole length of the stalk, for before it reaches either end, the point is bound down and bent backwards like a shep- herd's crook. It consists, according to Sir E. Home, of phosphate and carbonate of lime, making thus a near approach to the bone of vertebrate animals. Lect. Comp. Anat. i. p. 59.

The papillae on the back of the rachis, and between the pinnae, are disposed in close rows, and do not differ from the polype cells except in size. The latter are placed along the upper margin of a flattened fin ; they are tubular, and have the aperture armed with eight spinous points, which are moveable, and contract and expand at the will of the animated inmates. These are fleshy, white, provided with eight rather long retractile tentacula beautifully ciliated on the inner aspect with two series of short processes, and strengthened moreover with crystalline spicula, there being a row of these up the stalk, and a series of lesser ones to the lateral cilise. The mouth, in the centre of the tentacula, is somewhat angular, bounded by a white H- garaent, a process from which encircles the base of each tentaculum, which thus seems to issue from an apei tui'e. The ova lie betvi^een the membranes of the pinnae ; they are globular, of a yellowish co- lour, and by a little pressure can be made to pass through the mouth.

Bohadsch says that the Pennatulae swim by means of their pinnae which they use in the same manner that fishes do their fins. Ellis says it " is an animal that swims freely about in the sea," " many of them having a muscular motion as they swim along ;" and in ano- tber place he tells us that these motions are effected by means of the pinnules or feather-like fins, — " these are evidently designed by nature to move the animal backward or forward in the sea, conse- quently to do the office of fins." — Phil. Trans, abridg. xii. 42. Pal- las adopted, with some reservation, J the opinion of Bohadsch ; but Bosc, in an effort to be original, fancied that these remai'kable zoo- phytes lay during the winter at the bottom, concealed among sea- weed and in the crevices of rocks, while in summer they often swam at the surface ! Cuvier tells us that they have the power of moving by the contractions of the fleshy part of the polypidom, and also by the combined action of its polypes ; and, to adopt the words of Dr Grant, " a more singular and beautiful spectacle could scarcely be con- ceived, than that of a deep purple Pen. phosphorea, with all its deli- cate transparent polypi expanded and emitting their usual brilliant phosphorescent light, sailing through the still and dark abyss by the

• Misc. Zool. p. 177.

178 Z. ASTEROIDA. Pennatula.

regular and synchronous pulsations of the minute fringed arms of the whole polypi." And Bohadsch asserts that he has been a witness of this spectacle. " Deget nostrum Zoophyton in altiori mari, ubi in- terdum cum aliis piscibus capitur. Dum versus maris supei'ficiem fertur, buUulae innumerae corpus ejus circumdant, quae stellarum instar de die splendent ; id quidem non hac occasione, sed anno 1749, dum Liburno Marsiliam versus per mare proficiscerer, observavi. Quo tempore in historia naturali minime versatus corpus bullulis nitens ad quatuor circiter pedes infra superficiem maris conspiciens e nautis quaesivi, quidnam rei esset ? qui Pennam esse pro responso dedere." An. Mar. p. 107 — Linnaeus had thei'efore some grounds for inserting the " phosphox'escent Sea- Pens, which cover the bottom of the ocean, and there cast so strong a light, that it is easy to count the fishes and worms of various kinds sporting among them" — amongst the most memorable productions in Nature, See Smith's Tracts relating to Nat. History, p. 43. But some authors, as Lamarck and Schweigger, reasoning from what is known regarding other compound animals, have denied the existence of this great locomotive power in a zoo- phyte placed so low in the scale, as contrary to every analogy, and not necessary to the existence or wants of the animal. And there is little doubt these naturalists are right, for, when placed in a basin or plate of sea-water, the Fennatulae are never observed to change their position, but they remain on the same spot, and lie with the same side up or down just as they have been put in. They inflate the body until it becomes in a considerable degree transparent, and only streaked with interrupted lines of red ; they distend it more at one place and contract it at another ; they spread out the pinnae, and the polypes expand their tentacula, but still they never attempt to swim or perform any effort towards locomotion. Our fishermen believe that they are fixed at the bottom with their ends immersed in the mud, and the paleness of the base, when viewed in connection with the preceding observations, go far, in my opinion, to prove this statement to be correct. " Si les pennatules nagent aussi," says Blainville, " ce dont je doute un peu, quoiqu'elles rampent tres-lente- ment, c'est peut-etre en chassant le fluide qui est entre dans leur systeme acquifere, plutot qu'a I'aide des pinnules polypiferes." — Ac- tinolog. p. 83.

As the name imports, this Pennatula is a phosphorescent animal, but the light, of a faint blue colour, is emitted only under circum- stances that tend to shew that the polypes have felt some painful ir. ritation which they would drive away by the dread influence of their tiny lamps. I have repeatedly kept living specimens for several days

ViRGULAKiA. Z. ASTEROIDA. 179

in sea water, and have observed them at all hours, without once de- tecting them in a vohintary emission of the fiame. It proceeds solely from the polypes themselves, and can only be elicited by mechanical irritations, which have no sooner ceased than the phosphorescence declines and dies away.

" Spangling the waves with lights as vain As pleasures in this vale of pain, That dazzle as they fade."

Sir W.Scott.

13. ViRGULARiA,* Lamarck. Character. — Polype-mass free-, linear-elongate, " support- ing, towards the upper extremity, sessile lunate lobes embracing the stem obliquely, and bearing a row of cells on their margin."

1. V. uiKXBii.is, stem filiform, with alternate lobes transverse^ ly ridgedr Mr Simmons, f

Plate XXIV. Pennatiila mirabilis, Lin. Syst. 1322. Mull. Zool. Dan. prod. 255, no- 307-t — Zool. Dan. tab. 11, fig. 1-3. Ellis and Soland. Zooph. 63. Sowerhy, Brit. Misc. 51, pi. 25. Turt. Brit. Faun. 217. Jameson in

Wern. Mem. i. 565. Stew. Elem. ii, 450. Bosc, Vers, iii. 62

Virgularia mirabilis, Lam. Anim. s. vert- ii. 430, 2de edit. ii. 647. Flem. Brit. Anim. 507. Grant in Edin. Joiirn. of Science, no. 14. Stark,

Elem. ii. 420. Scirpearia mirabilis, Templeton in Mag. Nat. Hist. ix.

470 La Virgulaire aailes laches, £laitiv. Actinol. 514, pi. 90, fig. 3.

Hab. Dredged up by Mr Simmons off Inch-Keith, Sowerhy. Pres- tonpans Bay, Jameson. " On the east and north coast of Scotland, where it is believed by the fishermen to have one end lodged erect in the mud ; in Zetland it is called the Sea-rush," Fleming. Dredged up in Belfast Lough, Templeton.

" Seems to represent a quill stripped of its feathers. The base looks like a pen in this as in the other species, swelling a little from the end, and then tapering. The upper part is thicker, with alter- nate semicircular pectinated swellings, larger towards the middle, ta- pering upwards, and terminating in a thin bony substance, which

passes through the whole." Soiverby. " From 6 to 10 inches

in length." " They perfectly correspond in form and external ap- pearance with the elegant coloured figure given by INIuller. Their axis is calcareous, sohd, white, brittle, flexible, cylindrical, of equal

* Formed from Virgiila, the diminutive of Virga — a rod. f " A young man who has since fallen a sacrifice to his zeal for Natural His- tory in the West Indies." — Leach- He was, I believe, a native of Edinburgh.

180 Z. ASTEROIDA. Virgularia.

thickness throughout, and exhibits no mark of attachment at either end. When broken, it exhibits a radiated surface, like the broken spine of an echinus. The axis appears to have little connection with the fleshy part, and to consist of concentric layers deposited by the soft parts surrounding- it. When a portion of the axis is broken off from either extremity, the animal retracts at that part, so as con- tinually to expose a fresh naked portion of the axis : hence we can take out the axis entirely from its soft sheath, and we always find the lower pinnae of the animal drawn up closely together, as if by the frequent breaking of the base. These very delicate and brit- tle animals seem to be confined to a small circumscribed part of the coast which has a considerable depth and a muddy bottom, and the fishermen accustomed to dredge at that place believe, from the clean- ness of the Virgularise when brought to the surface, that they stand erect at the bottom with one end fixed in the mud or clay. Mul- ler's specimens were likewise found on a part of the Norwegian coast with a muddy bottom. The Polypi, much resembling those of the common Lobularia digitata, are long, cylindrical, transparent, marked with longitudinal white lines, and have eight tentacula which pre- sent long slender transparent filaments or cilise on each of the lateral surfaces when fully expanded. The polypi are easily perceived ex- tending through the lateral expansions or pinnae, to near the solid axis, where we observe two transverse rows of small round white ova placed under each pinna, and contained within the fleshy substance. These ova appear to pass along the pinnae, to be discharged through the polypi, as in the Lobularia, Gorgonia, Caryophyllea, Alcyonia, &c." Grant.

The figures in our plate were drawn from specimens with which I was favoured by Dr Coldstream, and which had been preserved for some time in spirits ; but to shew the difference between the animal in this contracted condition and when alive, I have placed beside them Figures 5 and 6, copied from Muller. The dissimilarity between figures taken in these diff"erent states has rendered the synonymy of the species perplexed and almost inextricable. According to Cuvier, Lamarck, and Blainville, the species delineated by Muller, and which is certainly identical with the British one, is not synonymous with the Linnaean ; but this opinion rests solely upon the circumstance of Linnaeus having quoted a figure in the " Mus. Ad. Fr." — belong- ing confessedly to another Zoophyte — as a representative of the spe- cies he intended, which may have been done from the then un- certainty of the limits of the species, or from having seen specimens in spirits only. His character is verv applicable to our animal, —

ViRGULARlA.

Z. ASTEROIDA.

181

" P. stirpe Jiliformi, rachi distiche pennata : pinnis lunatis remotis alternis ;" and the habitat " m O. Norvegico," seems to confirm the reference.

Virgularia differs from Pennatula remarkably in this that no spi- cula enter into the composition of its soft parts. The polypiferous pinnules are secund, leaving- the posterior part naked, and this is marked with a deep furrow extending- from one end to the other, dividing the polypidom into two symmetrical halves.

Fig. 24.

Fig, 25.

FAMILY V. GORGONIAD^.

14. GoRGONiA,* Linnaeus. Character. — Polype-mass rooted^ arborescent, consisting of a central axis barked with a polypiferous crust : the axis horny, continuous and flexible, branched in coequality icith the polype- mass : the crust when recent soft and fleshy, ivhen dried porous and friable : the orifices of the polype-cells more or less protube- rant.

1. G. VERRUCOSA, much and irregularly branched, the branch- es spreading laterally, cylindrical, flexuous, barked when dry loith a lohite icarted crust : segments of the cells unequal, obtuse.

Cole, t

Plate XXV. Fig. 1. Frutex marinus flabelliformis, Rail, Hist. Plant, iii- 7. Sir H. Sloane in

Phil. Trans, abridg. (an. 1746) ix. 198, pi. 4, fig. 4. Keratophyton

flabelliforme, cortice verrucosa obductum, Eaii, Syn. 32. Erica ma- rina alba frutescens, Petiv. Mus. cent. prim. 9, no. 50. Warted Sea- fan, Borl. Cornw. 238, tab. 24, fig. 1 Gorgonia verrucosa, Lin.

Syst. 1291. Pall. Elench. 196. Ellis and Soland. Zooph. 89- Turt.

• From Gorgon — the name of a daughter of Phorcys, whose locks of hair were changed into serpents by Minerva.

f Ray, in his Historia, mentions Mr, afterwards Dr, Cole of Bristol as the finder of this zoophyte on the coast of Cornwall. Cole is well known to natu- ralists by his ingenious enquiry into the purple liquor of the Purpura lapillus.

GoRGONiA. Z. ASTEROIDA. 183

C.mel. iv. 648- Turt. Brit Faun. 206. Cavol. Polyp, mar. 29, tav. 1, Hg. 1-11, and tav. 4, fig. 1-16. Lam- Anim. s. Vert. ii. 315. 2de edit. ii. 491. Bosc, Vers, iii. 36. Lamarck in Mem. du Mus. ii. 82. Corall. 207. Stew. Elem. ii. 430. Flem. Brit. Anim. 512- Risso,

I'Europ. Merid. v. 327 Gorg. viniinalis, Soiver- Brit. Misc. 81, pi.

40. Jameson iii Wern. Mem. i. 560. Turt. Brit. Faun. 206 La

G. verruqueuse, Blainv. Actinol. 505, pi. 87, fig. 3.

Hah. Deep water. " Mount's Bay in Cornwall," 3h' Batten. Plentiful on the Devonshire coast, Montagu. Said by Dr Walker to occur in Scotland, Jameson. " I have also received it from Scot- land," Sowerhy.

Polype-mass more than 12 inches in height, and 15 or 16 in breadth, fixed to rocks by a broad circular fibro-corneous disk, shrub-like, branched from near the base, the branches expanded la- terally, cylindrical, erect or erecto-patent, warty. Axis black, smooth and somewhat glossy, round or a little compressed, compact and cor- neous, with a snow-white pith in the centre, irregularly cellular and very like the pith of a rush ; near the extremities of the branches the axis appears to be a single tube striated longitudinally, but this appeai-ance is produced by drying, for when steeped in water the striae are removed ; it is often bulged or knotted at uncertain inter- vals, but no pores can be detected in its parietes. Crust white, cre- taceous, friable, warted with numerous polype-cells and wrinkled in the small spaces between them ; thickest towards the ends of the branches which it covers over. Cells partly filled with a yellowish fi- brous substance being the remains of the polypes, their orifices clos- ed with eight converging obtuse small segments, one of which is so much larger than the others as to occupy a half or a third of the whole circumference.

2. G. PLACOMUS, irregularly branched, the branches disposed in a dichotomous order and a Jlattish form, cylindrical, warty ; cells protuberant, conical, surrounded at top by little spines. Ellis.

Plate XXV. Fig. 2.

Warted Sea-fan, £//is, Corall. 67. no. 1. t. 27. fig. a, A. 1, 2, 3 Gor-

gonia placomus. Pall. Elench. 201. Lin. Syst. 1290. Mull Zool. Dan. prod. 254. no. 3061. Ellis and Soland. Zooph. 86. Turt. Gmel. iv. 649. Lamarck in Mem. du Mus. ii. 83. Turt. Br. Faun. 206. Berk. Syn. i. 212. Lam. Anim, Vert. ii. 316. 2de edit. ii. 492. Bose, Vers, iii. 31. Corall. 207. Stew. Elem.ii. p. 430. Flem. Brit. Anim. 512. La G. plac'ome, Blainv. Actinolog. 505.

Hah. Coast of Cornwall, Ellis.

184 Z. ASTEROIDA. Gorgonia.

" This Sea- Fan is of a reddish brown colour ;" " has its branches disposed in a dichotomons order and a flattish form ; they bend irre- gularly towards one another, but rarely unite. Their mouths are co- nical, project, and are surrounded at top by little spines. The bone or support is nearly of the substance of wood." Ellis.

3. G. ANCEPS, branched, suhdichotomous ; branches with the jieshfiat on each side, with a row of little mouths along both the margins. Mr Dale. *

Plate XXV. Fig. 3. Keratophyton dichotomum ; caule et ramulis leviter compressis, Rail, Syn.

.32 Sea Willow, Ellis, Corall. 68. no. 2, tab. 27, fig. g Gorgonia

anceps, Pall. Elench. 183. Ellis and Soland. Zooph. 89. Berk. Syn.

i. 212. Lin. Syst. 1292. Turt. Br. Faun. 206. Lam. Anim. s. Vert.

ii. 317. 2de edit. ii. 494. Lamour. Cor. Flex. p. 395. Turt. Gmel. iv.

649. Bosc, Vers, iii. 37. Lamarck in Mem. du Mus. ii. 84. Corall.

200. Stew. Elem. ii. p. 430. Flem. Brit. Anim. p. 512. La Gorgone

gladiee, Blainv. Actinol. 505.

Hab. Deep water, very rare. Found by Mr Dale growing near

Margate, Dillenius. Now and then found on the coast of Great

Britain and Ireland ; but not frequently, Ellis.

" This Gorgon is branched nearly in a subdivided manner." " The bone is roundish, and small at the ends, of a horny nature, inclining to leather." Specimens recent from the sea " are of a fine violet co- lour ; but when we receive them, some are yellow, others white." Ellis. The claims of this species to be considered a British native are doubtful.

The following species, referable to this family, have been indicat- ed as British, but neither figures nor descriptions of any of them, de- rived from native specimens, have been as yet published :

Gorgonia Flabellum, ^^ grows inform of a net, with its branches compressed inwardly : the flesh is yellow, sometimes pur-

• " Samuel Dale, Medicus et Pharmacopoeus vicinus et familiaris noster, Bantriae in Essexia degens," one of the four botanists to whom Ray acknowledges his greatest obligations in the compilation of his " Historia Plantarum." Praf. 1686 — He died in 1739, at. 80. Petiver aflfectionately styles him " my very kind friend," and " our curious brother." — In the latter peiiod of his life he set- tled as a physician at Bocking. He is the author of a " Pharmacologia," and of a History of Harwich, — both works of merit, and once of repute. See Pul- teney's Sketches, Vol. ii. p. 122-8- Pulteney says he was a F. R. S., but I do not find his name in the list of Fellows given by Dr Thomson.

GoRGONiA. Z. ASTEROIDA. 185

ple^ with stnall mouths placed irregularhj, having polypes with eight tentacles : the hone is black, horny, and slightly striated on the large branches.""

Vignette, No. 19, Page 161. Flabellum Veneris, Ellis, Corall. 61. pi. 26. fig. A— M. (foreign). Borl.

Cornw. 238 Gorgonia Flabellum, Lin. Syst. 1298. Mull. Zool.

Dan. prod. 253. Ellis and Soland. Zooph. 92- Berk. Syn. i. 212.

Turt. Grael. iv. 651. Turt. Brit. Faun. 206. Jameson m Wern. Mem.

i. 561. F/e/n. Brit. Anim. 511.

Hah. " The Flabellum veneris has been found on the shores of

Mount's Bay after a storm, but whether from a wrecked vessel, or

torn off by the violence of the waves from some rock in the Bay, is

not to be asserted positively," Borlasse. " Leith Shore, found by

the late Mr Mackay," Jameson, " Mr Neill informs me that he saw

Mr Mackay's specimen shortly after it was found, and that it had

all the aspect of being fresh and recent," Fleming.

Gorgonia lepadifera, " this Gorgon is dichotomous : it is almost covered ivith mouths, which are placed close together, hang- ing over one another ; they are bell-shaped, bent doivnicards, and full of small scales : the flesh is covered with minute whitish scales. The bone in the larger branches is testaceous, or rather like bone,

and in the smaller ones horny ^

Gorgonia lepadifera, Lin. Syst- 1289. Mull. Zool. Dan. prod. 254. Ellis in Phil. Trans, abridg. xiii. 728, pi. 12, fig. 12. Ellis and Soland. Zooph.

84. tab. 13, fig. 1, 2. Wern. Mem. i. 560. Stew. Elem. ii. 430

Primnoa lepadifera, Flem. Brit Anim. 513. Hab. " Found on the coast of Aberdeenshire, and coasts of Shet- land islands," Jameson.

Isis HiPPURis, " has a jointed stony stem, which rises into many loose branches. The bone or support of the animal consists oj white, cylindrical, stony, channelled joints, connected together by black contracted horny intermediate ones. The flesh is lohit- ish, plump and full of minute vessels ; the surface of it is full of the little mouths of the cells, which are disposed in a quincunx order, covering the polypes with eight claws."

Isis Hippuris, Lin. Syst. 1287- Ellis and Soland. Zooph. 105, tab. 3, fig. 1 — 5. Jameson in Wern. Mem. i. 560. Stew. Elem. ii. 429. Stark, Elem. ii. 427, pi. 8. fig. 7, 8- Hab. " Said by the late Dr Walker to occur on the east coast of Scotland, and also in the Orkney islands," Jameson.

186

Z. ASTEROIDA.

Isis,

Drayton, in the Poly-olbion, mentions the Isis as a product of Portland isle, but his Isis is probably the Corallina officinalis. I glad- ly quote the lines :

" Upon whose moisted skirt, with sea-weed fring'd about. The bastard coral breeds, that, drawn out of the brack, A brittle stalk becomes, from greenish tum'd to black ; Which th' ancients for the love that they to Isis bare (Their goddess most ador'd) have sacred for her hair. Of which the Naiads and the blue Nereids make Them taudries for their necks : when sporting in the lake, They to their secret bowers the sea-gods entertain."

Song 2.

The Isis Entrochus of Turt. Brit. Faun. 206, is a fossil species of Pentacrinus.

Fig. 26.

OrA OF THE GORGONIA.

Fig, 11.

FAMILY VI. ALCYONID^.

14. Alcyonium,* Linnaeus. Character. — Polype-mass lohed or incrusting^ spongious, the

♦ From Alcyon — the King's-fisher : the word itself signifies " sea-foam" of wbich the Halcyons were supposed to make their nests. See Lib- Entert- Knowl- " The Architecture of Birds ;" p. 45, &c.

" And every thing dispos'd it to my rest,

" As on the seas when th' Halcyon builds her nest.

" When those rough waves, which late with fury rush'd,

" Slide smoothly on, and suddenly are hush'd :

" Nor Neptune lets his surges out so long,

" As nature is in bringing forth her young."

Drayton's Heroical Epistles. To the reasons adduced by Milne- Edwards for retaining the name Alcyonium to this group, I would add that Lohularia is inadmissible, having been preoc- cupied by the botanists. The Alcyonium of Lamarck is composed of certain sponges, of which the true character remains unknown.

188 Z. ASTEROIDA. Alcyonium.

skin coriaceous, marked with stellated pores ; interior gelatinous, netted icith tubular fibres and -perforated loith longitudinal ca- nals terminating in the polype-cells, ichich are subcutaneous and scattered. Polypes exsertile.

1. A. DiGiTATUM, polymorphous, greyish-xchite or orange-co- loured, the skin someiohat wrinkled, studded over with stellated pores even tvitk the surface. Dillenius.

Plates XXVI. and XXVI*.

Alcyonium ramosa-digitatuni molle, astericis undiquaque oniatum. Raii, Syn. 31, no. 2. Breynius in Ephemerid. Acad. Leopold, cent. 8, app.

\ 59. Bast. Opus. Sub. i. 24. tab. 3. fig. 6, 7. pessima Main de mer,

Jussieu in Mem. Acad. Roy. des. Sc. an. 1742, 294, tab. 9, fig. 1

Dead Man's hand or Dead Man's toes, Ellis, Corall. 83, no. 2, pi. .32, fig.

a, A. A. 2. Alcyonium manus marina, Ellis in Phil. Trans, liii. 431.

tab. 20, fig. 10—13 A. digitatum, Ztn. Syst. 1294. Mull. Zool.

Dan. prod. 255, no. 3078. Fabric. Faun. Groenl. 447. Ellis and Soland. Zooph. 175, pi. 1, fig. 7. Berk. Syn. i. 212. Turt. Gmel. iv. 652. Jameson in Wern. Mem. i. 563. Turt. Brit. Faun. 207. Stew. Elem. ii. 431. Bosc, Vers, iii. 156, pi. 30, fig. 4, 5. Fleming in Edin. Phil. Journ. ix. 251. Cuv. Reg. Anim. iii. 321. Hogg's Stock. 38. Tem- pleton in Mag. Nat. Hist. ix. 470. Harvey in ibid, new series, i. 475,

fig. 56. 57, (very inacciu-ate) Ale. lobatum. Pall. Elench. 351.

Lamour. Cor. Flex. 336, pi. 12, fig. 4, and pi. 13, fig. omn. Corall. 243,

pi. 12, fig. 4 ; pi. 13, and pi. 14, fig. 1 Lobularia digitata, Lain.

Anim. s. Vert. ii. 413. 2de edit. ii. 631. Flem. Brit. Anim. 515. Grant in Edin. Joura. of Science, no. 15. Stark, Elem. ii. 421. Johnston in Trans. Newc Soc. ii. 250, pi. 8. Roget, Bridgvv. Treat, i. 162, fig.

56. Le Lobulaire digite, Blainv. Actinol. 521.

Hah. On stones, old shells, &c. in deep water. This is one of our most common marine productions, so that, on many parts of the coast, scai'ce a shell or stone can be dredged from the deep that does not serve as a support to one or more specimens. It appears often in the form of a mere crust about the eighth of an inch in thickness when removed from the sea and in a state of con- striction, but more commonly it rises \ip in conoid masses of vari- ous sizes and lobed in a very irregular manner. Sometimes the polypidom is a simple obtuse process, very much resembling the teat of a cow's udder, whence our fishermen have happily named it Coivs-paps : other polypidoms are more or less divided into finger- like lobes, and assume figures that have suggested the names of Dead Man's toes or Dead Man's hands. The outer skin is tough and coriaceous, studded all over with stellate figures which, if attentively

4

Alcyonium. Z. ASTEROIDA. 189

examined, are seen to be divided into eight rays, indicating the num- ber of the tentacula of the polypes, which issue hei'e. The body of the polypes is as it were enclosed in a transparent vesicular mem- brane, dotted with many minute calcareous grains, and marked with eight white longitudinal lines or septa which, stretching between the membrane and the centi'al stomach, divide the intermediate space in- to an equal number of compartments. These lines not only extend to the base of the tentacula, but run across the oral disk, and termi- nate in the central mouth. The tentacula are short, obtuse, ciliated on the margins, and strengthened at their roots by numerous linear straight crystalline spicula. From the base of the white longitudi- nal lines an equal, number of white tortuous glandular filaments de- pend, hanging loose in an abdominal cavity placed underneath the fleshy cylindrical stomach, and continuous with the aquiferous canals.* The Polype-cells are oval, placed just under the skin, and are the ter- minations of the long aquiferous canals which run through the whole polypidom. These canals divide in their course into branches that diverge towards the circumference where they dilate into the cells ; they have strong cartilaginous, perhaps muscular, coats ; and are fil- led with a much less consistent matter than that of the body of the polype itself. It appears, from this disposition of the tubes, that many polypes communicate together and form a compound animal, but that all the polypes of the same polypidom do not communicate directly by their medium. The space between the tubes is occupied by a loose fibrous net-work, and the threads being a little more crowded at particular places, they form lozenge-shaped compartments within which are smaller meshes ; and the interstices of the whole are filled with a transparent gelatine, in which numerous crystalline irregular spicula lie immersed. These spicula are mostly in the form of a cross and toothed on the sides, but they have no organic connection either with the reticular fibres or with the tubes : they are calcareous, for if a portion of the zoophyte is immersed in a mineral acid, a strong effer- vescence immediately takes place, and spicula are no longer discernible.

* A classical friend on seeing the specimen from which our figure was taken in full expansion, when it is translucent and permits a view of the interanea, was reminded of the following lines :

" In liquidis translucet aquis ; ut eburnea si quis " Signa tegat claro, vel Candida lilia, vitro."

" salientia viscera possis

" Et perlucentes numerare in pectore fibras."

Ovid. Met. vi. 354 and .390.

190 Z. ASTEROIDA. Alcyonium.

The ova are placed in tbe polype-tixbes ; they are white at first, but ultimately become of a scarlet colour, opake, globular, and about the size of a grain of sand. Each ovum is filled with a mass of ex- tremely minute pellucid granules, and is ultimately discharged through the mouth. They seem to be produced in spring and summer, for in June and July I have seen many specimens with not more than three or five polypes developed, and these are as large and perfect as the polypes of the oldest specimens.

Dr Fleming is of opinion, that the Alcyonium lobatum of La- mouroux, whose figure I have quoted without any mark of doubt, is a perfectly distinct species, because its tentacula " are sub-cylindrical, rounded at the extremity, and covered above and on the margin with blunt tubercles;" whereas of the British Alcyonium "the tentacula in Ellis's figures (and, having compared these with nature, we can pronounce on their accm'acy,) are pinnate and pointed." But of these figures of Ellis's, it may be observed that the one he has given in his essay on Corallines * is very unlike the figure of the same parts in his Nat. Hist, of Zoophytes ; and 1 must acknowledge that neither of them correspond with what 1 have myself seen. When a specimen of Alcyonium digitatum is placed in a vessel of sea-water, the polypes protrude themselves amazingly, and extend their tenta- cula, which are thick, obtuse, grooved along the centre, and not long- er than the diameter of the oral disk, being in fact very like what they are represented to be by Lamouroux ; but when these organs are removed and slightly pressed between plates of glass, they be- come so much elongated that 1 can readily believe they may, when the animal is active and in its native site, assume the shape and ap- pearance of Ellis's latter figure. And I am thus drawn to the con- clusion that the differences in the different figures will not justify the establishment of distinct species, but are to be attributed to the ani- mal being- in different states when observed, — a conclusion which a writer in the Encyclop. Method. Supp. p. 497, has also come to. *' Les figures donnees par Ellis, Spix et Lamouroux ne se ressemblent guire; je pense neammoins que cette difference ne peut etre rapportee a aucune inexactitude, mais depend de I'etat du polype a I'instant ou il a ete dessine."

The Alcyonium rubrum oi Mailer defined to be ^^ crust aceum, molle, miniatmn, punctis sparsis saturatiorihus," — Zool. Dan. prod. 255, no. 3081, — is, moreover, surely nothing else but this species in its primary crustaceous condition, and of a reddish-orange colour, as

* This figure it appears, was taken from specimens which had been immers- ed in spirits. Introd. to Corall. p. xii.

Cydonium. Z. ASTEROIDA. 191

I have occasionally met with it. I have not seen the original figure, but the copy of it given by Blainville, Man. d'Actinol. pi. 88, B, fig. 7, does not diminish the strength of my suspicion, which, how- ever, some may deem a very vague guess, when they observe that it has been referred even to a diftereut genus, and forms the Ardhelia rubra of the author just mentioned, Actinolog. p. 524 ; and the Sym- podium 7'ubrum of Ehrenberg. Lam. Anira. s. Vert. 2de edit. ii. 625.

16. Cydonium,* Fleming. Character. — " A coriaceous skin, internally carneous, with numerous straight ridged spicida, perpendicular to the surface. Polypi with a central opening, and an orifice at the base of each of the eight pinnated tentacula"

1. C. MuLLERi, ^^ skin yelloivish, ivith numerous stellate pores ; internally broivn." Jameson.

Alcyonium cydonium, " Mull. Zool. Dan. tab. 81, fig. 3, 4, 5-" Fabric- Faun. Groenl. 448, no. 464. Javieson in Wern. Mem. i. 563. Stew.

Elem. ii. 432 Lobularia conoidea, Lam. Anim. s. vert. ii. 413

Cydonium Mullen, Flem. Brit. Anim. 516. Grant in Edin. New Phil.

Journ. i. 195 La Cydonie de Muller, JBlainv. Actinolog. 525, pi. 92.

fig. 2. Hab. " Island of Fulah and Unst," Jameson. " Base of adhesion narrow, body massive, surface irregular ; the skin consists of animal matter cementing innumerable round siliceous grains ; the cells leading from the stellate pores are indistinct ; the spicula, which converge towards the centre, are fusiform, grouped in small bundles, and many of them at the skin are tricuspidate. In a dried specimen from Zetland, which I have had an opportunity of ex- amining through the kindness of Professor Jameson, the surface is slightly villous, owing probably to the contraction of the skin, leav- ing the extremities of the fibres free. With the exception of the stellate pores, it agrees with the Alcyonimn primum Dioscoridis of Donati ( Adriat. 56. t. ix. f. 1.) in the villous skin and the simple and tricuspidate spicula." — Fleming.

In the 2d edit, of Lamarck's Anim. s. Vert. ii. 632, I find it stated that Ehrenberg considers the Alcyonium cydonium of Muller as founded on a young individual of Alcyonium digitatum, of which, in- deed, it has much the appearance ; but the zoophyte which Dr Flem- ing has had in view, seems to be different.

* Cydonium — a quince, in allusion to the figure of the Zoophyte.

192 Z. ASTEROIDA.

In the " Annals of Natural History" for May 1838, Mr J. E. Gray has inserted the following notice — " Miss AttersoU has lately discovered, on the coast of Sussex, the Cornularia rugosa of Cavolini, growing on a Tubularia, and has communicated specimens of these interesting zoophytes to the British Museum. This genus has hitherto been believed to be confined to the Mediterranean. It diifers from most other horny zoophytes in the tentacles being pin- nate like those of Gorgonia." V. i. p. 238.

To enable the student to identify this species— certainly among the most singular of its order — I have given a copy of Cavolini's figure, (Vignette, No. 27, p. 187) ; and it may be useful to add the generic cha- racter : " Polyparium basi affixum, corneum ; surcuHs simplicibus, in- fundibuliformibus, erectiusculis, polypum unicum singulis continenti-

bus. Polypi solitarii, terminales : ore tentaculis octo dentato-pinna-

tis, uniserialibus." Lam. Anim. s. Vert. ii. 128, 2de edit.

On the eve of the preceding remarks being sent to press, I receiv- ed from Mr J. E. Gray a specimen of the Cornularia from " Wey- mouth." I agree entirely with this sagacious naturalist in his opinion of the identity of the zoophyte with Cavolini's. In texture it accords with Sertularia. The root-like fibre is filiform and tubu- lar, creeping in a flexuous manner, along the stem of Tubularia indi- visa, and putting out at irregular intervals, tubular vase-like cells from two to three lines in height. The cells are smooth, with a narrow base and a wide even aperture. (Fig. 23, a and b, p. 181.)

The examination of it has thrown new light on the Polypidom described at p. 157, under the name of Campanularia dumosa. I have there expressed my doubts as to the real position of that species, and I had indeed a suspicion of its being an ascidian zoophyte allied to the Vesicularia. Now, however, there can be little doubt that it

a Cornularia, probably identical with the C. rugosa, for its com- paratively smaller size may depend on peculiarity of habitat. To shew their similarity, 1 place a figure of it beside the other. (Fig. 24, a, i. p. 181.)

IS

BRITISH ZOOPHYTES.

PART IV

ZOOPHYTA HeLIANTHOIDA.

Fig. 28.

0^

0

°*^^f^;^^'^-'i^

Css?

l#

'm^m^^Wj'^^/^'

■3

LUCERNARIA AURICULA-

in the waters we may see all creatures.

Even all that on the earth are to be found,

As if the world were in deep waters drown'd.

For seas have

As well as earth — Vines, Roses, Nettles, Melons,

Mushrooms, Pinks, Gilliflowers, and man}' millions

Of other plants, more rare, more strange than these,

As very lishes, living in the seas."

Du Bartas. N

" Mihi firme persuadeo, eum, qui plantas marinas et insecta marina perscru- tari velit, magna perfusum iri voluptate : est enim hie novus raicrocosmus, cujus incolae parum innotuerunt, sed qui propter proprios propagandi modos, ri- tus, oeconomiam, aliasque qualitates, attentione Naturae venatoris sunt dignissi- mi." — J. Basterus.

" and made their beauties known,

" Not without moral compliment."

Crabbe.

" Still life was theirs, well pleasing to themselves,

" Nor yet unuseful, as my song shall show.

* * * * v

"_ — — _ — — All

" Life's needful functions, food, exertion, rest,

" By nice economy of Providence

" Were overruled to carry on the process,

" Which out of water brought forth solid rock."

Montgomerij.

ZOOPHYTA BRITANNICA.

ORDER III. Z. HELIANTHOIDA.

Charactku. Polypes separate or compound, free or attached, Jlosculous ; the body regular tvith a circular periphery, contractile, internally divided into numerous spaces by perpendicular muscular septa : mouth superior and central, encircled ivith one or more series of tubular tentacula : stomach membranous : anus 0 : ovaries and cceca placed in the septa between the stomach and skin.

Observations. I borrow the name of this order from Latreille, * but give to it a wider appUcation than it has in the classification of that il- lustrious naturalist, that it may embrace the madrepores and starred stones, which the observations of Le Sueur, confirmed as they have been by subsequent voyagers, demonstrate to be the products of zoophytes similar, in all essential points, to the naked Actiniae. The order thus corresponds to the class " Zoantha" of De Blainville, — a name which has the claim of priority, and might have been adopted by me, had not its con- junction with zoophyta appeared inappropriate, as involving a tautology. The term preferred expresses the resemblance which the animals it designates have to the compound or syngenesious flowers, — a resemblance which has been very generally re- marked, and the source of the name — Sea Anemonies — by which the typical species are known in this country. When speaking of these Ellis says, — " their tentacles, being disposed in regu- lar circles, and tinged with a variety of bright lively colours, very nearly represent the beautiful petals of some of our most

* Fam. du Rcgiic Animal, p. 535.

196 ZOOPHYTA HELIANTHOIDA.

elegantly fringed and radiated flowers, such as the Carnation, Marygold, and Anemone." The language of Le Sueur in re- spect of the tropical coral-bearing tribes is still warmer. The little polypes of Porites astroides, when in blow, remind him of a field enamelled with small flowers ; and of them in general he says, — " Quand la mer est calme, c'est un spectacle admira- ble que de voir les belles couleurs veloutees qu'ils e'talent : elles imitent les tapis les plus riches et les plus varies. Pres d'eux se montrent des gorgones et des serpules dont les houpes blanches, jaunes et rouges, brillent de I'eclat le plus vif, et des amphitrites qui elevent au-dessus de I'eau leur tete couronnee de palmes enrichies des teintes les plus variees. Je ne pouvois me lasser d'admirer avec quelle profusion ces animaux sont groupes et enlaces : c'etoit a regret qu'apres m'etre promene long-temps au milieu d'eux je me determinois a les arracher du sein des eaux, et a en mettre des fragments dans un baquet, que je faisois de suite transporter chez moi pour examiner a loisir les animaux particuliers a chacun des polypiers." * — It is only, however, when they lie with their upper disk expanded and their tentacula displayed, that they solicit comparison with the boasts of Flora, for when contracted the polypes of the madre- pores conceal themselves in their calcareous cups, and the Ac- tiniae hide their beauty, assuming the shape of an obtuse cone or hemisphere of a fleshy consistence, or elongating themselves into a sort of flabby cylinder that indicates a state of relaxation and indolent repose.

The Actinia gemmacea is the only species which the anato- mist has yet examined with care, f but it may safely be chosen as the representative of its order, the probability being that the deviations from its structure in the other species and genera are only of secondary consequence. Of the species mentioned Mr Teale has given a very elaborate anatomy, :}: more correct and minute than any hitherto published, but the sketch to suit our design, must be of a more general character.

* Memoires du Museum, Tom. vi. p. 272 and 287.

f M. Delle Chiaje has, it seems, anatomized several other species, but I have no access to bis works. Bull. des. Sc. Nat. xvii. 470.

I " On the Anatomy of Actinia coriacea, by Thomas Pridgin Teale," in Transactions of the Leeds Philosophical and Literary Society, Vol. i.

ZOOPHYTA HELIANTHOIDA. 197

The body of the Helianthokla may be compared to a trun- cated cone or short cyHnder, seated on a flat plain base, while the opposite end is dimpled in the centre with the oral aperture, and garnished with variously figured tentacula which originate from a space between the proper lip and the free somewhat thickened border of the disk. In a state of contraction the mouth is closed, the tentacula are shortened, and the whole concealed by this border, being drawn like a curtain over them, leaving a mere depression on the top. The mouth leads by a very short and wide passage into a large stomach, which is a membranous bag puckered internally with numerous plaits, and divided in a perpendicular direction into two equal halves, by a deep smooth furrow with cartilaginous sides, as was first remark- ed by Reaumur.* There is no intestine, nor any other visible exit from the stomach than the mouth, bv which the undigested remains of the food are ejected, always enveloped in a large quantity of a clear glairy fluid. But in a state of expansion and of hunger, many kinds of Helianthoida can protrude the stomach beyond the lip in the form of large bladder-like lobes, which often hang over the sides and almost conceal the rest of the body ; and amidst them there are very frequently extruded at the same time some white filaments, like bundles of ravelled thread, which have escaped either through a rupture, or a cir- cular opening in the bottom of the stomachal membrane. The space between the walls of this organ and the outer envelope is divided into numerous narrow compartments by perpendicular and parallel lamellae of a musculo-tendinous texture, which ex- tend from the oral disk to the base, and radiate to the centre like the gills of a mushroom to its stalk, — a comparison the more exact as some only of the lamellae reach and touch the stomach, the rest coming more or less short, and forming consequently imperfect interseptal spaces. " The breadth of the leaflets va-

* " They (the furrows) are produced on each side by the firm adherence of the gastric membrane to a i)air of very dense, fleshy, but narrow leaflets, through- out their whole extent, or, in other words, from the top to the bottom of their internal border. These depressions divide the animal into two lateral halves, constituting a bilateral symmetry in Actinia, as has been observed by M. Agassiz

in other supposed radiated animals." Teale in loc. cit. 102 But in Actinia

Dianthus the channel or furrow exists on one side only.

198 ZOOPHYTA HELIANTHOIDA.

ries considerably, some extending scarcely a line from their ex- ternal attachment, others reaching as far as the stomach, being nearly half an inch in breadth. The height generally corre- sponds with the height of the animal ; a few, however, of the narrowest leaflets extending upwards from the base, terminate obliquely in the sides, without being prolonged as high as to the lip or roof."* These lamellae are of a muscular character, and by their actions cause the body to assume its various forms. The spaces between them are filled, 1st, with the ovaries attached, in elongated masses, to the inner border of most of the leaflets ; and 2dli/, with the " vermiform filaments" which, as already mentioned, are often extruded at the mouth. These filaments are capillary, greatly convoluted, smooth and of a white colour, with a sort of mesentery extended along one side. Their ap- pearance naturally suggests the idea of their being either the in- testines or the oviducts of the creature, but they perform no function of the kind ; and probably they are csecal, analogous to the filaments which hang from the stomach of the asteroid zoophytes. They have been often described as ovarian, even by late authorsjf but Mr Teale has fully shewn the improbabihty, if not the erroneousness of this opinion. He believes the fila- ment to be tubular, though he acknowledges he has not been able to obtain any evidence of the fact, and " under the micro- scope it appears simply as a round, solid, translucent chord." Such also has it always appeared to me, so that I can scarcely hesitate to pronounce Dicquemare's description of its structure to be altogether incorrect. " I have observed," he says, " that there grows or comes out of their body and mouth a sort of threads about the size of a horse-hair, which being examined with a solar microscope of five inches diameter, appear as if made up

* Teale in Trans. Leeds' Soc. i. 96.

f " Entre ce sac interieuv (the stomach) et la peau exterieure, est une orga- nisation assez compliquee, mais encore obscure, consistent surtout en feuillets verticaux et fibreux, auxqiiels adherent les ovaires, semblables a des fils tres en- tortilles." Cuvier, Reg. Anim. iii. p. 290. Delle Chiaje in Bull, des So. Nat. xvii. 471. See also J. R. Jones in Cyclop, of Anat. and Physiol, ii. 409 — Sharpey describes them as oviducts. Cyclop, cit. i. 614. Dicquemare had a singular notion that they contained certain bulbs or buds " which open in time and cleaving to the bodies on which these threads are extended, produce small anemonies." Phil. Trans, abridg. xiii. 6.39.

ZOOPHYTA HELIANTHOIDA. 199

of a prodigious number of vessels, wherein a liquor is seen to circulate. The largest of these unite together, much in the same manner as the optic nerves do in man."*

The external envelope of the naked Hydroida is a thick firm fleshy or coriaceous skin consisting of a corium and epidermis, — the former layer constituting the chief organ of support, and giving to the animal its peculiar form. " A circular horizontal portion forms the base or foot ; a cylindrical vertical portion constitutes the sides, and is inflected at the superior border, so as to form a thick rounded lip. The corium is afterwards pro- longed over the tentacula, ffivinof investment and form to these organs, and is then extended horizontally to form the roof, near the centre of which it again becomes folded upon itself, forming an internal lip or mouth, at which part it is continuous with the digestive sac." f — " The epidermis forms a thin layer of unor- ganized matter spread over the whole extent of the corium, and may be traced into the stomach. The external surface of the epidermis is dense and membranous ; internally, when examin- ed by the lens, it appears as a pulpy substance. Intimately in- termixed with it, in irregular patches, and not constituting a dis- tinct or separate layer, is a pigment varying in colour in different parts of the same animal, and in diff"erent individuals. This colouring matter is extensively distributed over the base, sides, tentacula, and roof, but I have never observed any trace of it in the stomach." I The surface is either smooth or studded over with glandular warts, which, having an adhesive quality, enable the creatures the more completely to conceal themselves by in- duing the body with an extraneous coat formed of the sand, gravel, and broken shells which lie around their peculiar locali- ties. This is exchang'ed in the madrecolous tribes for the more perfect defence which a hard coral affords, into which the soft parts are withdrawn at will. " This coral is calcareous, and the cells which are inhabited by the animals are furnished with more or less distinct longitudinal lamellae, placed in a radiating posi- tion round the central axis, so as to give the cavity a star-like appearance." § Its structure is in fact a model cast in lime of what may be called the skeleton of the Actiniae, — the parts on

» Phil. Trans, abridg. xiii. 6.39. t Teale in lib. supra cit. 93.

J Teale in loc. 95. § Gray in Synop. of British Museum, 70.

200 ZOOPHYTA HELIANTHOIDA.

which the support depends being converted into stone by a de- position of calcareous matter in their texture, — the corium in this manner becoming a sohd polypidom, and the muscular leaf- lets partitions of limestone.*

When a Helianthoid Polype is at rest and unalarmed, it can dilate the body to fully twice its ordinary bulk by imbibing water through the mouth or tentacula,-f- the bases of which open in the spaces between the perpendicular lamellae. These spaces being filled, the water is then made to permeate the rim of the oral disk, which is full of cavities and cells for its recep- tion ; and the tentacula are in the same manner distended, the water being forced into them from behind while the little open- ing on their tips is held close. The whole animal is thus dis- tended to a wonderful degree, and every organ stretched and displayed;— the tentacula spread out in quest of prey, — the skin rendered almost clear from very fulness ; and the stomach, pushed beyond its natural bounds, lies over the sides in swol- len diaphanous lobes. The water thus introduced is doubtless subservient to the purposes of respiration, and to aid this, the vermiform filaments, and the internal surface of the stomach and tentacula are clothed with vibratile cilia, exciting and di- recting currents over the surfaces.:}: Since too the contents of the stomach must be fully exposed to the influence of the water, the

" " Dans cette classe d'animaux, le polypier ou la partie solide qui reste quaiid le partie animale a ete dessechee et enlevee, est done une sorts de reseau calcaire d"un tissu plus ou moins compacte, qui remplissoit les mailles, les vacuoles de celle-ci. La proportion de ces deux parties est en rapport avec I'age du zoan- thaire : plus il est jeune, plus il y a de matiere animale ; plus il est age, et plus il y a de matiere inorganique : aussi la base de ces polypiers, le plus souvent morte, est-elle fort dure, tandis que le sommet ou les bords essentiellement vi- vans sont entierement mous." Blainville, Actinolog. 311 — See also Harvey in Mag. Nat. Hist. n. s. 1. 474.

•f " It has not, so far as I know, been clearly shevra by which of the com- municating orifices the water enters. Though I took considerable pains, I have not been able satisfactorily to ascertain this point ; I may remark, however, that I have repeatedly noticed water entering at the mouth." Sharpey in Cyclop.

Anat. and Phys. i. 614 Delle Chiaje asserts that it enters by the tentacula.

Bull, des Sc. Nat. xvii. 471. He adds, " II est curieux d'observer le courant d'eau qui, lorsque T Actinic se relache, penetre par quelques tentacules, et des qu'elle se contracte, sort par d'autres tentacules precisement opposes aux pre- miers. Ce phenomene s'observe sur toutes les especesd'Actinies." ^ Sharpey in lib. cit. i. 614 — 15.

ZOOPHYTA HELIANTHOIUA. 201

nutrient parts may be by its means fitted for more immediate assimilation, for as there is neither circulating nor lymphatic sys- tems, the absorption of the nutrient fluids must be made direct- ly from the stomach itself. By the contraction of the periphery of the body, this water is again expelled at pleasure through the tentacula in a continuous stream or in jets, and if the contrac- tion is sudden and strong, the water may be thrown out with such force as to rise to the height of at least a foot. It is re- markable that the water does not escape from all or the great- er number, but only from a few of the tentacula. Whether any part escapes by the mouth is doubtful.

All the native species are single, viz. every individual is iso- lated and complete in itself, and not organically associated with others, as the polypes of the preceding orders are. They are also all oviparous, the ova being generated in appropriated or- gans. According to Spix the ova, in the Actinise, form several grape-like clusters, situated in the interseptal spaces, with ducts which open into the base of the stomach by several apertures, and hence the ova are presumed to gain their freedom by tra- versing the stomach and mouth.* Blainville doubts this, being led from analogy to believe it more probable that the oviducts may open in the labial rim, as they do in the asteroid zoo- phvtes. -f- Delle Chiaje says that they terminate in the tentacula of the Actiniae ;% and Cavolini states, that in the Caryophyllia the ova are discharged through small distinct openings between each of the tentacula.§ Their natural passage of egress may be considered to be undetermined, but it seems to be ascertain- ed that they do, under certain circumstances, escape from the body sometimes through the tentacula, or in apertures between them, and sometimes through the mouth. Mr Teale, after vainly attempting to discover any proper oviduct, thinks it probable that the ova, when sufficiently matured, " actually burst their mem- branous envelope, and become lodged in the interseptal spaces where they are exposed to the free access and continued sup- plies of sea water, the grand stimulus to their further develope-

" Cams, Conip. Anat. Trans, ii. 308, pi. i. fig. x.

f Man. d'Actinologie, 79-

f Bull, des Sc. Nat. xvii. 471.

§ Edin. New Phil. Journ. i. 153.

202 ZOOPHYTA HELIANTHOIDA.

ment."* The supposition readily explains some facts which have given rise to an opinion of their viviparous generation, for the young will be born alive if the easy admission is made that some of the ova may have their egress delayed until they have passed through their first stages of evolution. That many ova, and pro- bably by much the greater number, escape previously to this is now well ascertained.

Mr Teale's description of the ovaries varies also from Spix's, and is very accurate. In Actinia gemmacea he tells us they form " elongated masses attached along the inner border of most of the leaflets. Each ovary is composed of several hori- zontal folds or plaits, which, when unfolded, show this structure to be about three times the length it assumes when attached to the leaflet. By carefully spreading out these folds, the ovary, with the assistance of a lens, is seen to consist of two very de- licate layers of membrane, enveloping a closely compacted layer of ova. After enveloping the ova, the membranous layers are placed in apposition, and form a kind of mesentery, by which the ovary is attached to the internal border of the leaflet. The two layers afterwards separate to pass one on each side of the leaflet, thereby lining the interseptal spaces from which this membranous investment is prolonged into the tentacula, as well as into the cavities within the structure of the lip and mouth. At the summits of the tentacula, and of the tubular eminences of the lip, the membrane becomes continuous with the common integument, whilst at the inferior part of the interseptal spaces it is continuous with the digestive sac. The breadth of the ovaries is nearly uniform from the top to the bottom. Some ir- regularities are occasionally observed in their attachment to the leaflets. Sometimes one leaflet supports two ovaries, and not unfrequently two neighbouring ovaries are continuous with each other at their inferior extremities." '\-

The period of propagation is probably, in most Helianthoida, not limited to any particular season. According to the obser- vations of Cavolini the Caryophyllia matures its ova in spring ; and it is only at this season that I have found the Lucernarise on

* Leeds Phil, and Lit. Soc. Trans- i. IIL f Lib. supra cit. p. 104.

4

ZOOPHYTA HELIANTHOIDA. 203

our northern shores, when they are big with numerous eggs. But in the Actini;e, ova in every state of developement may be seen in the same individual throughout the year ; perhaps, however, they are most abundantly laid in autumn. They are usually of a roundish figure, and, like the gemmules of polypes in general, contractile and motive, being carried about from the action of the cilia that clothe the surface. " Under the microscope they prove of diversified form, many resembling flattened pease, some elongated or exhibiting irregular prominences, some almost spherical, others as if composed of two or even of three un- equal spheres, and some which cannot be referred to any par- ticular figure." After moving about for several days, during which their forms suffer some slight change, they insensibly relax in their activity, the cilia disappear, and, having become stationary, each rapidly runs through the stages of develope- ment that lead it up to the similitude of its parent.

Every one has read of the coral islands of tropical seas ; how they grow from the fathomless profound, and how they rise to day by the operations of puny insects, which, in countless num- bers, and in untold generations, effectuate changes on our globe superior, perhaps, to what all other animals united do, and com- pared to which the greatest achievements of " intellectual man," sink to insignificance.* Geology teaches us that with these worms the great work of creation began ; and from that uncer-

* " Their plants are made of stone, and they build dwellings. Dwellings ; — they construct islands and continents for the habitation of man. The labours of a worm, which man can barely see, form mountains like the Apennines, and regions to which Britain is as nothing. The invisible, insensible toil, of an ephe- meral point, conspiring with others in one great design, working unseen, un- heard, but for ever guided by one volition, by that One Volition which cannot err, converts the liquid water into the solid rock, the deep ocean into dry land, and extends the dominions of man, who sees it not and knows it not, over re- gions which even his ships had scarcely traversed. This is the Great Pacific Ocean ; destined, at some future day, to be a world. That same power which has thus wrought by means which blind man would have despised as inadequate, by means which he has but just discovered, here too shows the versatility, the contrast of its resources. In one hour it lets loose the raging engines, not of its wrath, but of its benevolence ; and the volcano and the earthquake lift up to the clouds, the prop and foundation of new worlds, that from those clouds they may draw down the sources of the river, the waters of fertility and plenty." Dr Macculloch, Highlands and West. Islands, Vol. iv. p. 14.

204 ZOOPHYTA HELIANTHOIDA.

tain date even to the present day, their amazing labours have been continued, the product remaining in the extensive ranges of limestone rocks which lie buried in our northern regions, as well as in those islands of new formation with which they threat- en to convert the equatorial seas into dry land. " They that sail on the sea tell of the danger thereof ; and when we hear it with our ears we marvel thereat."*

" Millions of millions thus, from age to age,

With simplest skill, and toil unwearyable,

No moment and no movement unimproved,

Laid line on line, on terrace terrace spread.

To swell the heightening, brightening gradual mound,

By marvellous structure climbing tow'rd the day.

Each wrought alone, yet all together wrought,

Unconscious, not unworthy, instruments.

By which a hand invisible was rearing

A new creation in the secret deep.

Omnipotence wi'ought in them, with them, by them ;

Hence what Omnipotence alone could do

Worms did. I saw the living pile ascend,

The mausoleum of its architects.

Still dying upwards as their labours closed :

Slime the material, but the slime was tum'd

To adamant, by their petrific touch ;

Frail were their frames, ephemeral their lives,

Their masonry imperishable." f

By much the greater number of those wonder-working zoo- phytes belong to this order. In former ages ihe geologist tells us that they were numerous and varied in our seas, — their re- mains, entombed in limestone and marble, constituting the mo- dels by which he decyphers their forms and species ; but this ancient host is now represented by two or three species only, and these so small and rare, that it would be giving them a dis- proportionate importance to make them more than the subject of a passing allusion to the labours of their races.

The British species may be arranged under the following genera ;

' Ecclesiast. chap, xliii. v. 24.

t IMontgomery's Pelican Island, canto ii. p. 27.

ZOOPHYTA HELIANTHOIDA.

205

Family I. MADREPHYLLIiEA. Body cased icith a solid calcareous cupped polypidom, lamel-

lated internally.

17. TuRBiNOLiA. Polypidom turbinate, becoming free by age.

18. Caryophyllia. Polypidom cylindrical, always attached.

Family II. ACTINIID^.

Body naked^Jleshy, contractile^ locomotive.

19. Actinia. Body conoid or cylindrical ; the tentacula retractile.

20. Anthea. Body cylindrical ; the tentacula non-retractile.

21. Lucernaria. Body somewhat campanulate ; the tentacula in tufts disposed at distant intervals round the margin.

Fig. 29.

Actinia viduata.

III. ZOOPHYTA HELIANTHOIDA.

FAMILY VII. MADREPHYLLI^A.

17. TuRBiNOLiA,* Lamarck. Character. Animal like the Actinia, single : Polypidom fixed token young, becoming detached in the progress of its growth, simple, inversely conical, furrowed on the outside, pointed at the base, and terminating above in a lamellated stellular cell.

\. T. BOREALis, " widely conical, slightly bent." Rev. Dr Fleming.-|-

Fungia turbinata, Fleming in Wern. Mem- ii. 250. Turbinolia borealis,

Flem. Brit. Anim. 309 La Turbiiiolie boreale, Blainv. Actinolog. 341.

Hah. " Zetland," Fleming.

" This species occurred in the same boat in which I picked up the Caryophyllea cyathus. Thoug-h greatly defaced, it still exhibits proofs of its recent origin. It is inversely conical, pointed, subarcu- ated, with a concave disc and a prominent centre ; the plates appear to have been equal. It is about five-tenths of an inch in height, and nearly the same in breadth across the star." Fleming.

Lamouroux maintains, in opposition to Lamarck, that the Turbino • liae are fixed, and says that in well preserved specimens a distinct pedicle, with the point broken ofi^, is obvious. J The fact seems to be, as stated

* From turbo, a top.

f The author of the " Philosophy of Zoology," and the " History of British Animals." He, for many-years, discharged the duties of a minister of the Church of Scotland ; and is now Professor of Natural Philosophy in King's College, Aberdeen. To his labours and writings I am inclined to ascribe a considerable share in diffusing that taste for natural history which is now abroad.

\ Soland, Zooph. new edit. p. 51.

CARyoiHYJ.LiA. Z. HELIANTHOIUA 207

by Mr J. E. Gray,* that they are fixed in their rirst stage of existence, but become detached by age. Dr Fleming, to his description of the species, adds, " From its shape, it appears probable, that it grows with its base fixed in the sandy bottom of the sea, as Pallas formerly con- jectured."

18. Caryophyllta, f Lamarck. Character. Animal like the Actinia : Polypidom permanent- ly Jixed^ simple^ cylindrical or conoid, striated externally in a lon- gitudinal direction, the top holloiced into a lamellated stellular cup.

1. C. S'SUTHU, polypidom cylind7'ical ; lamelloi entire, arched, faintly crenate, from 3 to 5 smaller ones beticeen the larger ; centre tubercular. Rev. Dr Fleming.

Vignette, No. 30, page 206. Caryophyllia cyathus, Fleming in Wern. Mem. ii. 249 ; and in Edin. New Phil- Journ, viii. 70. Broderip in Ibid. viii. 312. Flem. Brit. Aiiim. 508. — C. Sniitliii, Stokes and Broderip in Zool. Journ. iii. 486, pi. 13, fig. 1-6. and in Bull, des Sc. Nat. xvii. 157. Buckland, Bridgew. Treat, ii. 90, pi. 54 fig. 9-11. Harvey in Proc. Zool. Soe. 1834, part ii. 28 : and in Mag. Nat. Hist. New Series, i. 474, fig. 5b- Hah, " From deep water off Foulah, in Zetland," Fleming. Southern coast of Devonshire, Thomas Smith, Esq. Cornwall, Mr Coutch.

The Polypidom is firmly attached to the rock so as apparently to make a part of it : it is cylindrical, whitish stained with brown, stri- ated or finely grooved on the exterior, internally cupped and lamel- lar. The lamellae are of three kinds, a larger and more prominent, between every pair of which there are generally three, but sometimes five lesser ones, of which the central one differs from the others in being divided into two portions, the innermost half projecting beyond the others towards the centre and forming an inner series. J All

* SjTi. of Brit. Museum, p. 70. See also in relation to this point Mr Stutch- bury's observations on the growth of young Corals of the genus Fungia, in Lin. Trans, xvi. p. 493.

f From KA^voy, anut, and<?i/X?iov,a leaf. — The name has been so generally re- ceived that it might be difficult to substitute another for the genus, and yet it is very objectionable. There is a Caryophyllceus amorg the intestinal worms ; and the Caryophyllece are familiar to all botanists — The following generic cha- racter of Caryophi/llia is given by Mr Stokes : " Polyparium simplex, basi affixum. Corona lamini.s duplici serie dispositis, cxterioribus majoribus, re- gulariter insequalibus, maximis inter seriei internie laminas interpositis. Dis- cus lamellis erectis, prominulis foliatis."

\ Dr Fleming describes the plates thus -. " The lamellseare disposed in fours.

208 Z. HELIANTHOIDA. Caryophyjllia.

the lamellae are arched, entire, striated on the sides, whence the mar- gin appears somewhat crenulate : they terminate about half across leaving- a plain centre which is roug-h or tubercled. In one specimen before me the primary lamellae are 14 in number ; in another they are 20 ; but Dr Fleming gives about 40 as the number in his Zetland specimen. Height from two-tenths to half an inch ; diameter three- tenths to one inch.

My friend Dr Coldstream has furnished me with the following account of the animal of this interesting zoophyte, which he watched for several successive weeks during his residence at Torquay. " When the soft parts," he writes, " are fully expanded, the appear- ance of the whole animal resembles very closely that of an Actinia. When shrunk they are almost entirely hid amongst the radiating plates. The specimens I have seen have varied in size from three- tenths to one inch in diameter, and from two-tenths to half an inch in height. They are found pendant from large boulders of sandstone just at low water-mark ; sometimes they are dredged from the mid- dle of the bay. Their colour varies considerably ; I have seen the soft parts white, yellowish, orange- brown, reddish, and of a fine apple green. The tentacula are usually paler. During expansion, the soft parts rise above the level of the calcareous disc to about twice its height. The tentacula are pushed forth very slowly, but some- times are as long as the whole height of the body. They are ter- minated by a rounded head. * The mouth has the appearance of an elongated slit in the centre of the disc : it is prominent, and the lips are marked with transverse striae of a white colour. When a solid body is brought into contact gently with the tentacles they ad- here pretty strongly to it, just as the Actiniae do ; but when they are rudely touched, they contract very quickly, and if the irritation

and may be distinguished into three different kinds. The first are the highest and the broadest at the margin, but as they descend into the disc they become narrower before they join the central plate. The second kind are narrower than the preceding at the margin, but towards the middle they suddenly enlarge and join the middle plate. The third kind are the smallest and terminate be- fore reaching the middle plate- The space included between a pair of the first kind of plates, contains one of the second kind in the middle, with one of the third kind in each of the lateral spaces. Those on the sides are rough, with small scattered tubercles, and their margins are curled. This last circumstance occasions the roughness externally, where the longitudinal striae are the remains of the gills. The plate which occupies the bottom of the cavity is smooth, vari- ously twisted, and connected with the base of the lateral plates."

' " They are nearly transparent except at the termination, which is a little ball, white and opake." De la Beche.

MiLLEPORA. Z. HELIANTHOIDA. 209

be continued, the wliole soft parts sink within the calcareous cup." 5th April 1833.

PociLLOPORA iNTEUSTiNCTA. Madrepora interstincta, Mull. Zool. Dan. prod. 252 — Dr Fleming (Brit Anim. 511) has seen a specimen <' probably of this species," obtained by Dr Hibbert in Zetland, but I am not aware that any description of it has been yet published.

Madrepora musicalis, Lin. Syst. 1278. Berk. Syn. i. 211. Turt. Gmel. iv. 625. Turt. Brit. Faun. 204. — Said to be some- times cast on the Irish coast ; but without the slightest claim to denization.

Madrepora porpita, Turt. Gmel. iv. 616 A fossil confound- ed with the M. porpita of the Indian seas.

MiLLEPORA TRUNCATA, Stew. Elem. ii. 426- Marked erroneous- ly as British.

MiLLEPORA LICHENOIDES, Tuvt. Brit. Fauu. 204. Turt. Gmel. iv. 635. — I am not aware on what authority this has been introduced into our native Fauna by Dr Turton. Ellis says nothing that can lead one to suppose that his specimen was British.

Fig. 31.

FAMILY VIII. ACTINIID.E.

19. Actinia,* Linnseus. Character. Body conoid or cylindricaly adhering by a broad base : the space between the mouth and the rim of the up- per disk occupied by one or more uninterrupted series of conical undivided tubular tentacula lohich are entirely retractile.

1. A. MESEMBRYANTHEMUM, body conoid, smooth ; tentacu- la numerous, multiserial ; margin of the oral disk ornamented with a circle of azure-blue tubercles.

Var. a. Body and tentacula of a uniform liver-broMTi or olivaceous colour, rarely streaked with bluish or green lines.

Vignette, No. 31.

Ortie de mer, Reaumur in Mem. de I'Acad. Roy. des Scienc. 1710, pi. 10. fig. 22 Priapus equinus, Lin. Syst. edit. 10. 656. Hydra disci- flora, tentaculis retractilibus, extimo disci margine tuberculato, Gccrtner

in Phil. Traas. lii. 83, pi. 1. fig. 3. Actinia equina, Zm. Syst. 1088.

Dicquemare in Phil. Trans. Ixiii. 364, pi 16, fig. l-Tf Mull. Zool.

* From uKTiv, a ray.

f Dicquemare himself uses no specific names": they were applied to his figures by Dr Solander, who, it is to be presumed, was well acquainted with the Linnjean species.

Actinia. Z. HELIANTHOIDA. 211

Dan. prod. 231, no. 2793. Turt. Gmol. iv. 104. Flem. Brit. Anim. 497. Cuv. Reg. Anim. iii. 292. Bosc, Vers, ii. 255. Johnston in Trans. Newc. Soc. ii. 243. Dalyell in Edin. New. Phil. .lourn. xvii. 41] ; and in Proc. Brit. Assoc. 1834, 599. Templeton in Mag. Nat.

Hist. ix. 303. A- mesembryanthemiim, Ellis and Soland. Zooph. 4.

Turt. Brit. Faun. 131. Rapp, Polyp. 52, taf. 2, fig. 1. J ohiiston in

Mag. Nat. Hist. viii. 81, fig. 12 A. hemispherica, Pen. Brit. Zool.

iv. 104. Berk. Syn. i. 186. Hogg's Stock. 30 A. rufa. Mull. Zool.

Dan. prod. 231. Zool. Dan. tab. 23, fig. 1-^. Pen. Brit. Zool. iv. 105. Jameson in Wern. Mem. i. 558. Stew. Eleni. i. 393. Lam, Anim. s. Vert. iii. 67. Stark, Elem. ii. 412. Rapp, Polyp. 53. Boget, Bridgevv.

Treat, i. 198. fig. 86, 87 A. Anemone, Pm. Brit. Zool. iv. 106.

Hogg's Stock. 30 A. corallina, Risso, L'Europ. Merid. v. 285

A. margaritifera, Templeton in Mag. Nat- Hist. ix. 304, fig. 50 Com- mon Actinia, Buckland, Bridgew. Treat, ii. 89, pi. 54, fig. 4 Hydra

mesembryantliemum, AVew. Elem. ii. 451. Small red Sea- Nettle, Wal- lis. Hist, of Nortliumb. i. 374. Var. ^. Body paler striped longitudinally \\dth white ; tentacula annulated with white.

Vignette, No. 29, page 205. Actinia viduata, Mull. Zool. Dan. prod. 231, no. 2799. Zool. Dan. pi. 63, fig. 6-8, — copied in Encyclop. Method, tab. 72, fig. 4, 5. Johnston in Mag. Nat. Hist. viii. 82, fig, 13. Turt. Gmel. iv. 101. Lam. Anim. s. Vert. iii. 68. Bosc, Vers, ii. 256. Hub. On rocks between tide-marks, very common. Body one or one and a half inch in diameter, hemisphei'ical when contracted, when relaxed forming a short cylinder with a breadth gi'eater than the height, of a uniform liver-colour or often olive-green, and sometimes streaked with blue or greenish lines, either continu- ous, or in spots : the base generally of a greenish colour encircled with an azure-blue line, but it is often also streaked with red, and the blue marginal Une is wanting. The tentacula, when fully extended, are nearly equal to the height of the body, and of the same colour. The tubercles within the margin of the oral disk are formed by pa- pillary projections of the parenchyma of the body, covered over on the top with a thick layer of dense blue matter : in it, as well as in the skin generally, minute fusiform calcareous spicula, some slenderer than others, may be detected in abundance with the microscope.

In its young state, A. mesembryanthemum is liable to greater va- riations in colour than when mature. One of these varieties, as it seems to me, constitutes the A. viduata of Muller, distinguished by its light olive body striped with white ; while the tentacula are pret- tily ornamented with white and olive green rings. This variety usu- ally attaches itself to shelving rocks, where it is covered over and concealed by a layer of sand, protruding the tentacula through a small aperture at the surface opposite the mouth. On the recess of

212 Z. HELIANTHOIDA. Actinia.

the tide, nothing of the animal can be seen, and its presence in a lo- cality is only to be guessed at by the holes in the sand, which, how- ever, are exactly like the holes of many arenicolous worms.

Actinia niesembryanthemnm lives between tide-marks, and is most plentiful near that of high water. It is consequently often left ex- posed to the open atmosphere, but it expands only when covered with water. It never, so far as I have observed, emits from the mouth, like the other species, any thread-like tangled filaments ; nor does it seem to have the power of protruding the membrane of the stomach in the form of vesicular lobes. Gsertner says that " the colour of its body is always red in the summer, but changes into a dusky green, or brown, towards the latter end of autumn," — a remark which certain- ly does not hold good on the northern shores of Britain, where the red and dusky green varieties may be found intermingled at all seasons.

2. A. Bellis, " body lengthened^ the lower part narrow, smooth, the upper enlarged and glandularly loarty ; oral disc ex- panded, lohed ; tentacida in several rows, variegated." Gaertner. Hydra calyciflora, tentaculis retractilibus variegatis ; corpore verrucoso,

Gaertner in Phil. Trans, lii. 79. tab. 1, fig. 2 Actinia Bellis, Ellis

and Soland. Zooph. 2. Turt. Gmel. iv. 103. Turt. Brit. Faun. 131.

A. pedunculata, Pen. Brit Zool. iv. 102. Berk. Syn. i. 186. Lam.

Anim. s. Vert. iii. 70. i?osc, Vers, ii. 258. Stark, Elem. ii. 412. Flem.

Brit. Anim. 498. Templeton \nMa.g. Nat. Hist. ix. 303. Hydra bellis,

Stew. Elem. ii. 431. Hah. " Frequently found in the pools about the Mount's Bay," Cornwall, " It is rare to meet with a single one in a place, there being most commonly four or five of them living so near together in the same fissure of the rock, which they constantly inhabit, that their expanded calyces form a row of flower-like bodies, that seem to grow upon the dig's under water," Gcertner. " Found in a pool on the rocks at the north end of the Island of Rathlin, August 1795," Templeton.

"From its small basis rises a cylindric stalk, which supports the roundish body of the animal, from whence afterwards the calyx, being a continued membrane of the body, draws its origin. The stalk, or the pedunculus of the polype, is quite smooth, and its colour inclines towards the carnation. The outside of the calyx, and the body of this animal, are marked with a number of small white protuberances, resembling warts, to which fragments of shells, sand-grains, &c.adhere, and hide the beautiful colour of these parts, which, from that of car- nation, is insensibly changed towards the border of the calyx first in- to purple, then violet, and at last into a dark brown. The inside of the calyx is covered with the feelers, that grow in several ranges

Actinia. Z. HELIANTHOIDA. 213

upon it : they differ considerably in length ; those that are near the edge of the calyx being but small papilla^, in proportion to those that surround the disk, or the central ])art of the body. They are almost transparent ; and some of them are of a pale ash colour, with brown spots ; others, on the contrary, are of a chesnut colour^ marked with white spots. The disk is formed like a star, which, according to the figure that is traced out by the innermost row of the feelers, consists of many angles. The colour of this part of the body is a beautiful mixture of brown , yellow, ash-colour and white, which together form variegated rays, that from the centre, or the mouth of the animal, are spread over the whole surface of the disk. This polype contract- ing- itself, changes its body into an irregular hemisphere, which is so covered with the several extraneous bodies that stick to it, that it is extremely difficult to know the animal in this state, and to discern it from the rubbish, that commonly surrounds it." Gcertner. Perhaps a variety of the A. gemmacea.

3. A. iNTESTiNALis, " hodij cylindrical, the wpyer half sud- denly contracted and nnrroio" Dr Fleming.

Actinia intestinalis, i^air. Faun. Groenl. 350, no. 342, pi. I, fig. 11. Flem. Brit. Anini. 498. Hah. " Adheres to rocks at low water-mark, Zetland," Fleming. " When contracted, the body seems like two broad rings, of near, ly equal breadth, and about half an inch in diameter ; when expand- ed to nearly two inches, the body consists of two cylindrical portions of different dimensions, smooth, pellucid, yellowish ; a few longitudi- nal white streaks under the skin ; oral disk not expanded, surround- ed with about 18 filiform tentacula in two alternate rows." Fleming.

4. A. GEMMACEA, hody conoid, variously coloured, rough icitk glandular warts or sometimes smooth ; tentacxda numerous, in 3 or 4 series, shorter than the diameter of the oral disk, thick, and generally variegated with red and v;hite rings.

Plate xxvii. Actinia senilis, Fle/n. Brit. Anim. 498. Juhnston in Trans. Newc. Soc. ii.

244. Var. «. Body warty, the warts large and arranged in vertical rows Ortie

(le mer, Beaumur in Mem. de I'Acad. Roy. des Scieiic 1710, pi. 10, fig.

21, 23 — 26 Hydra disciflora, tentaculis retractilibus subdiaphanis ;

corpore cylindiico, miliaribus glandulis longitudiiialiter striate, Gartner

in Phil. Trans, lii. 82, tab- 1, fig. 4 Hydra gemmacea. Stew. Elem.

ii. 451 Actinia gemmacea, £//(s and Soland. Zooph. 3. Turt. Gmel.

iv. 104. Turt. Brit. Faun. 131. Wern. Mem. i. 558 A. verrucosa,

Penn. Brit Zool- iv. 1C3. Berh. Sjm. i. 186. Lam. Anim. s. Vert.

iii. 70. Stark, Elem. ii. 412. Bupp, Polyp, p. 50 A. glaudulosa

214 Z. HELIANTHOIDA. , Actinia.

Bosc, Vei-s,ii. 259 A. monile (the young,) Templeton in Mag. Nat.

Hist. ix. 303, fig. 49. A. Bellis, Rapp, Polyp. 30. tab. 1, fig. 1, 2.

Var. y3. The body warted, the warts equal, distinct, but scattered without

order over the surface. Act. senilis, Dicquemare'm Phil. Trans. Ixiii.

367, tab. 16, fig. 10 ; and tab. 17, fig. 11, 12. Penn. Brit. Zool. iv. 105-

Blumenh. Man. 246. Templeton in Mag. Nat- Hist. ix. 303. A. cori-

acea, Cuv. Reg. Anim. iii. 291. Rapp, Polyp- 51, tab. 1, fig. 3, 4. Teale in Trans. Leeds Soc. i. 91, pi. 9, 10, U.

Var. y. Body warted, the warts distant, equal, and sometimes obscure

Act. equina, Sowerby, Brit. Misc. 7, pi. 4. Turt. Brit. Faun. 130.

Penn. Brit. Zool. iv. 106. A. effoeta? Rapp, Polyp. 34, taf. 2, fig.

2. Templeton in Mag. Nat. Hist. ix. 303. Var. <r. Body quite smooth, irregularly clouded with scarlet, tentacula an-

nulated with red and white Priapus sive Actinia proboscidibus crassis

rotundis, Bast. Opusc. Subsec. i. lib. 3. 143, tab. 13, fig. 1 Act. feli-

na, Lin. Syst. 1088. Barhut, Gen. Verm. 53, tab. 5, fig. 6. Bosc, Vers,

ii. 255 A. coccinea. Mull. Zool. Dan. prod. 231, no. 2792. Zool.

Dan. tab. 63, fig. 1-3. (young.) Bosc, Vers, ii. 253. Lam. Anim. s.

Vert. iii. 68. A. crassicornis. Mull. Zool. Dan. prod. 231. Adams in

Lin. Trans, iii. 252. Penn. Brit. Zool. iv. 105. Turt. Gmel. iv. 100- Turt. Brit. Faun. L30. Stew- Elem. i. 393. Lam. Anim. s. Vert. iii. 67. Stark, Elem ii. 412. Fabric. Faun. Grcenl. 348, no. 341. Jame- son in Wern. Mem. i. 358 A. truncata, Jamesonin Wern. Mem. i.

538. Pe?in. Brit. Zool. iv. 106. Turt. Gmel. iv. 101. Turt. Brit. Faun. 131. Hab. In crevices of rocks between tide-marks, and on shells, &c. in deep water, very common.

Body usually rather more than two inches in diameter, hemispheri- cal when contracted, covered with glandular warts, arranged some- times in regular perpendicular lines, sometimes irregularly, and some- times they are scarcely or not at all obvious. The tentacula are dis- posed within the circumference of the oral disk, in 3 or 4 close rows ; they are thick, short, obtuse, somewhat compressed, almost always annulated or variegated with white and red, but when the body is of a uniform pale, flesh, or cream colour, the tentacula are of the same colour and without rings. The animal protrudes from the mouth at pleasure four or five vesicular, pellucid, scored lobes, which vary in size according to their degree of evolution, and often hang over the sides. When kept for a few days in a basin of sea-water, it becomes much larger in all its parts, paler and almost diaphanous ; and the tentacula elongate themselves, swell out, and are distinctly seen to be tubular. These adhere tenaciously to foreign bodies, for their apices act as suckers, and carry prey to the mouth in spite of all its strug- gles.

This species is liable to great variation in colour and size. The

Actinia. Z. HELIANTHOIDA. 2J5

littoral varieties, or such as are alternately submerged and exposed by the recess of the tides, are always strongly warted, generally orange - coloured with dusky blotches, and coated with particles of broken shells, small gravel and pieces of sea-weed, by which means, when contracted, they are detected with difficulty in the recesses or sandy places which they prefer. This foreign covering adheres to the glands W'ith great tenacity, and cannot be removed by any natural causes to which the Actinia is exposed ; but what is surely worthy of our ad- miration, and seems to prove the existence of an instinct even in these lowest creatures, the individuals which are placed in deep water, as if aware they did not require such a mode of concealment, form no extraneous covering, but leave the surface clean, and this acquires then more vivid and varied tints, while at the same time the warts become smaller or disappear. Of these pelagic sorts there are some eiuinently beautiful : one is of a uniform bright scarlet studded over with pale warts like ornamental beads ; another is of a pale sulphur yellow, or greenish with orange-coloured stripes, the oral disk and ve- sicular lobes borrowing the hues of the wild rose ; but they vary in this respect so much that no description can do justice to them or define their limits.

I have little doubt that all the synonymes quoted under this spe- cies truly belong to it. Gsertner's figure represents it of a more cylindrical shape than I have ever seen it assume, and with only a single row of rather slender tentacula, which, he says, vary from 18 to 36 in number. Hence the figure we may suppose to have been taken from a young individual, which is certainly the case in the Ac- tinia monile of Mr Templeton.

Dicquemare says — " Of all the kinds of sea-anemonies, I would prefer this for the table ; being boiled some time in sea water, they acquire a firm and palatable consistence, and may then be eaten with any kind of sauce. They are of an inviting appearance, of a light shivering texture, and of a soft white and reddish hue. Their smell is not unlike that of a warm crab or lobster." Phil. Trans, abridg. xiii. 637.

Ehrenberg divides the family Actiniidse into two sections, — the second embracing such genera as have glandular pores in the skin. The genus '* Cribrina," in this section, has Act. gemmacea for its type, which is thus far sundered from the species with which it is here associated. Ehrenberg seems to me to have been peculiarly unfortunate in his choice of a character, for if I have studied the ani- mal rightly, so far from being of sectional or generic value, it serves not even to discriminate a species, which may have its smooth and

216 Z. HELIANTHOIDA. Actinia.

glandular varieties, passing too into one another by such " unpei*- ceived shades" that the limits cannot be distinctly defined. Nay, as Mr Teale has also noticed, I have seen specimens which were glan- dular on one-half of the body and smooth on the other, illustrating in a striking manner the inconstancy of the structure, and its subordi- nate value.

In most systematic works on British Zoology there is an Actinia effcetay which is referable sometimes to this species, and sometimes to Act. maculata. The Act. effceta of Linnaeus, Syst. 1088, is found- ed on the " Tertia Priapi marini sive Actiniae species" of Baster, Opus. Subsec. 143, tab. 14, fig. 2. This figure is very unlike any variety of Act. gemmacea, or any other species with which I am ac- quainted. All the description Baster gives is this : " Directas ilia habet in corpore strias, et inferne basin, sive marginem, qua se affigit."

5. A. DiANTHUS, body cylindraceous^ smooth ; oral disk marked in the centre with clavate radiating hands ; tentacula nu- merous, irregular, the outer small and forming round the margin a thick filamentous fringe. Ellis.

Plate xxviii. Priapus sive Actinia proboscidibus tenuibus brevibus, Ba&t. Opusc. Subsec i. lib. 3, 143. tab. 13. fig. 2 — 4. (bene) — Actinia senilis, Lin. Syst.

1089.* Actinia Dianthus, jEZ/w in Phil. Trans. Ivii. 436. tab. 19. fig. 8-

Ellis and Soland. Zooph. 7. Shaw, Nat. Misc. xiii. pi- 539 ; (copied from Ellis and coloured from the description !) Turt. Gmel. iv. 104. Turt.

Brit. Faun. 131. Stew. Elem. i. 394. Flem. Brit. Anim. 498

Fourth species of Anemony, Dicqnemare in Phil. Trans, abridg. xiii. 638. pi. 12. fig. 9 — A pentapetala, Pe7in. Brit. Zool. iv. 104. Berk. Syn. i. 187. Lam. Anim. s. Vert. iii. 71. Bosc, Vers, ii. 259. Actinolobe

ceillet, Blainv. Actinol. 322 A. plumosa, Mull Zool. Dan. prod. 230.

no. 2791. Zool. Dan. tab. 88. fig. 1. 2. (drawn when the animal has been in a very relaxed and half expanded condition.) Turt. Gmel. iv. 100. Turt. Brit. Faun. 130. Stew. Elem. i. 394. Lam. Anim. s. Vert. iii. 68. Bosc, Vers, ii. 256. Stark, Elem. ii. 412. Cuv. Reg. Anim. iii. 291. Rapp, Polyp. 55, tab. 3. fig. 1. (good) Johnston in Trans.

Newc. Soc. ii. 246. La Metridie plumeuse, Blainv. Actinol. 321

A. senDis, Barb. Gen. Verm. 53. tab- 5. fig. 5. Adams in Lin. Trans. v. 9. Lam. Anim- s. Vert. iii. 68. Stark, Elem. ii. 412 — Hydra Dian- thus, Stew. Elem. ii. 451. Hob. On rocks and shells in deep water or within low tide-mark.

* Linnieus quotes two distinct figures of Baster for his senilis, but as he sub- sequently refers to one of these figures for his effceta, the other (tab. 1 3. fig. 2. ) must be considered as representing the true senilis.

Actinia. Z. HELIANTHOIDA. 217

At Hastings in Sussex, Ellis. Tenbigh, Wales, Adams. Frith of Forth, Dr Coldstream. Berwick Bay, common.

When contracted the body is of a thick short sxibcylindrical form, deeply wrinkled in two or three places, about three inches long, and one-half of that in diameter, but when fully expanded about five inches : the skin is quite smooth, and of a uniform whitish, cream or flesh-colour. The centre of the oral disk is ornamented with a circle of white bands radiating from the mouth, and the transparency of the skin here permits us to see the lamellae running across the cir- cumference with their narrow colourless interspaces. From these interspaces the tentacula originate ; the largest about one inch long, watery, white, tapered, smooth, irregularly dispersed, and very nu- merous. They are all placed between the mouth and the margin, which is encircled with a dense fringe of inimitable beauty, com- posed of innumerable short tentacula or filaments forming a thick furry border.

I have seen specimens of this species, which is certainly as MuUer says " actiniarum pulcherriraa," from the size of a split pea to fully five inches in diameter, and have found it, in all the intermediate sizes, uniform in shape and colour, but others have found it variable in these respects. It is strictly gregarious, and the larger individuals are generally surrounded by a multitude of small and middle-sized ones, which form very pleasing groups. From this gregarious habit it is subject to monstrosities, two or three occasionally uniting and coalescing into one body, of which Dicquemare has described an ex- ample.

" This species is good to eat," according to Dicquemare ; and his testimony may be strengthened by the authority of Plancus, who says of his " Urtica soluta caryophyllura referens," — a synonyme probably of A. Dianthus, * — " hsec more ostrearum coquitur, et una cum ipsis, quibus, ut dixi, frequentissime heeret, comeditur." Plane. de Conch, min, not. 43, tab. 4, fig, 6. +

No one who has studied the species but will, I think, assent to the conjecture of Cuvier that the A. Dianthus of Ellis is a mere variety of the A. pluraosa of subsequent authors, the former having had the oral disc deeper lobed than is usual from peculiarity of position or

• If this opinion is correct, and to me the thing seems indisputable, then the Actinia judaica, Lin. Syst. 1088, and of all other systematists who have fol- lowed him, must be added to the aliases of A. Dianthus.

f In reference to these edible Actinia I may here remark tliat the Anemonia edulis of Risso, which, according to Rapp, is synonymous with the Anthea Ce- reus of this work, furnishes the dish called Rastegna, a favourite in Provence. " Nostrates vero hoc cibo delectari nonduni comperi." Baster,

218

Z. HELIANTHOIDA.

Actinia.

from the mere will of the creature, which has great powers of con- tractility. This being assumed, we are entitled to say to Oken, who makes one genus of the Dianthus, and another genus of the plumosa, — " Generis falsa est ea fabula vestri."

Mr Templeton under the name of" A. dianthus ?" describes a species which appears tobe distinct. — "Conic, rounded above, of a green or greenish-yellow colour, with a few scattered warts in longitudinal rows ; disk light blue, often divided into 1 1 lobes ; tentacula numerous, pale, in from 3 to 7 fascicuh, variegated with dark annuli. In the hollows of the rocks at Ballyholm Bay, Bangor." Mag. Nat. Hist, ix. 304.

6. A. MACULATA, hasc fixed to a thin horny expansion attached to the apertures of various dead shells ; body longitudinally sul- cated, marked ivith purple spots ; tentacula numerous, rather short, arranged in three or four irregular rows. Mr Adams.

Fig. 32.

Actinia maculata, Adams in Lin. Trans, v. p. 8. Turt. Gmel. iv. 105. Penn. Brit. Zool. iv. 104. Coldstream' in Edin. New Phil. Journ. ix. p.

2.36. t. 4. f. 6. 7. and in Edin. Journ. Nat and Geog. So. iii. 49 A.

carciniopados, Otto in Nov. Act. Acad. C. L. C. Nat. Cur. xi. 288. pi.

40. Parasite Aetinea, Landsborough in Scottish Christian Herald, ii.

333 A. effoeta, Turt. Brit. Faun. p. 131. Turt. Gmel. iv. 101.

Hab. Milford Haven, surrounding the apertures of deserted shells of the Murex despectus, Adams. Torbay ; and in Rothesay and Karnes Bays in Bute, either thrown ashore after easterly gales, or drawn in by flounder-nets, Dr Coldstream. Stevenston, Ayrshire, Hev. D. Landsborough.

" This beautiful species is longitudinally sulcated, having the edges of the base crenated : the lower part is an obscure red, and the up- per part is transparent white marked with fine purple spots ; the outer cii'cumference of the aperture has a narrow stripe of pink.

Actinia. Z. HELIANTHOIDA 219

When expaiuled, the superior division of the body seems formed of fleshy bars placed in a reticulated manner, and lined with a fine membrane. From perforated warts, placed without order on the outer coat, issued white filameutose substances variously twisted together : I have observed a similar body ejected from the mouths of all the species of this genus which have fallen within my notice." Adams.

The following- more detailed description of this very interesting

species is by Dr Coldstream. " General mass of the animal flattened and extended ; thickness at the oral disc three-tenths of an inch, di- minishing towards the circumference of the base ; longest diameter of the base about three inches ; margin minutely crenated ; colour of the body, near the base, reddish brown, passing gradually into a light cream colour towards the oral disc ; whole surface striated longitudi- nally with alternate opaque white, and translucent bluish lines, and marked irregularly with bright reddish-purple spots. These spots are confined to the outer coat, which is easily peeled off". That be- low it is of a pink colour, and is marked with the strise, which shine through the outer coat. Oral disc of an elongated oval form, white, and bearing on its outer margin numerous rather short tentacula ar- ranged in three or four irregular rows : tentacula shorter than the body, acuminated, white, each marked with a faint streak of brown ; mouth large, oval ; lips white, contracted into folds ; internal sur- face of the stomach marked with numerous white strise. Base fixed to a thin horny expansion attached to the apertures of va- rious dead shells, such as Trochus cinerarius and T. Magus, and form- ing, as it were, an extension of the body- whorl of the shell in a spir- al form. Over this, the Actinea is spread entirely, and covers also more or less of the shell. Its oral disc is uniformly situated close to the inner lips of the horny case. The aperture of the case is accu- rately surrounded by its body, the margins of the opposite sides of which meet, and are closely applied to one another at the middle of the outer lip of the aperture, whence they run upwards towards the old shell, where they generally separate again, leaving its apex un- covered." " The horny membrane to which the Actinia is

attached, covers, for the most part, nearly the whole of the external surface of the ,old shell to which it is fixed, and from the circumfe- rence of its aperture, is prolonged into a large hollow expansion, re- sembhng in form, and occupying, relatively to the shell, the place of, a ventricose body-whorl. Its substance is of a uniform thickness throughout its whole extent, of a greenish-brown colour, translucent, having both surfaces irregularly wrinkled transversely. In a recent state it is quite flexible, but when dried it is brittle. It takes fire and burns readily, leaving a very small residuum, which does not ef-

220 Z. HELIANTHOIDA. Anthea.

fervesce with acids. It is insoluble in boiling water and in alcohol, but dissolves slowly in acids, and in solutions of the alkalies. Its general appearance may be compared to that of the cases of Tubularia indivisa, except in point of colour."

" The case thus formed by the old shell and the horny membrane, and covered by the Actinia, I have always found inhabited by a va- riety of the hermit-crab." " Its natural history is perhaps doubt- ful. Is the horny case secreted by the Actinia? Or is it the dead axis of some zoophyte, like that which covers old Buccina (Alcyoni- um echinatum, Fl.), and which I have found forming an extension of the body-whorl of the Turbo littoreus, also inhabited by the Pa- gurus ? Or, is it likely that the old shell, with a young crab in it, may have been swallowed by the Actinia ; that the crab may have forced its way through the walls of the stomach, and the integuments of the latter, and that, the Actinia then secreting a peculiar mem- brane to defend its base, the crab may have found itself provided with a habitation suited to its wants ? To this last supposition an objec- tion is found in the fact, that the full grown shell of Trochus Magus forms sometimes the base of the horny case, and this shell is too large to enter the mouth of the Actinia. It seems to be probable that the horny membrane is produced by the Actinia ; and that its formation presents a striking instance of the operation of that beautiful law of Nature which makes the habits of one animal subservient to the wants of another."

Bohadsch, in his work de Animalibus marinis, has described a spe- cies nearly allied, if not identical with the above, under the name of Medusa palliata, p. 135 t. 11. f. 1 : which is probably identical with the Actinia picta of Risso, L'Europ, Merid. v. 286. See also a no- tice by Professor Jameson in Edin. New. Phil. Journ. July 1830, p. 332.

20. Anthea,* Johnston. Character. Body cylindraceous, adhering by a broad base : tentacula disposed in circles round the mouthy elongated, taper- ed and incapable of being retracted within the body.

* From rti/floc — a flower : the name borrowed from Drayton — " Anthea, of the flowers, that liath the general charge, " And Syrinx of the reeds, that grow upon the marge."

The genus was first proposed, and indifferently characterized by Risso under the name of Anemonia, which being the same as Anemone must be rejected, for it" new generic names formed by the mispelling of old ones were tolerated, confu- sion and barbarism would soon be the result-

Antiiea. Z. HELIANTHOIDA. 221

1. A. Cere us, body someichat ci/lindrkal, furrowed length- loays ; tentacula numerous, longer than the body, smooth. Dr Gsertner.

Hydra tentaculis denudatis, numerossimis ; corpore longitudinaliter sulca-

to, Gcertner'm Phil. Trans, lii. 78, tab. 1. fig. 1 Act. Cereus, Ellis

and Soland. Zooph. 2. Turt. Gmel. iv. 103. Turt. Br. Faun. 131.

Rapp, Polyp. 56, tab- 2, fig. 3 Act. sulcata, Pen. Brit. Zool. iv.

102. Berk. S}7i. i. 18G. Stew. Elem. i. 394. Flem. Brit. Anim. 498.

Lum. Anim. s. Vert. iii. 69. Bosc, Vers, ii. 257 Hydra Cereus,

Stew. Elcm. ii. 4.51. Hab. " Very frequent upon the sea- coasts" of Cornwall, Gcertner. Anglesey, Pennant. Torquay, Dr Coldstream.

" The body of this polype is of a light chesnut colour, and feels perfectly smooth, though it be lengthways sulcated by a number of sulci, that are frequently divided into three smaller ones, and are continued into the dentated margin that surrounds the upper peri- phery of the body, just beneath the insertion of the feelers. These feelers, arising from the disk of the polype, are, according to the age of the animal, between 120 and 200 in number ; they exceed the body, when expanded, by more than an inch in length, and are of a beautiful sea-green colour, except towards their extremities, which are coloured with a lively red, like that of the rose. The disk is of the same brown colour with the rest of the body, and contains in its cen- tre the mouth of the animal, which is an aperture of various shape

and diameter. The two varieties of this species, which I met

with, differ but little from the already described animal. The feelers of the one, instead of being green, are throughout of a red colour, like that of the mahogany wood. The other variety has pale ash- coloured feelers, marked with a small white line running along their back ; its body is of the same chesnut coloiar with that of the first species ; but the sulci are not divided, nor has it a dentated margin surrounding its upper periphery." Gartner. The Act. sul- cata of Templeton, which he says is " most probably the young" of Actinia effceta, Mag. Nat. Hist. ix. 303, can scarcely belong to this species.

2. A. TuEDiiE, body sometohat cylindrical, smooth or wrink- led with circular folds; tentacida numerous, shorter than the body, lonyifudinally striate. G. J.

o.>o

Z. HELIANTHOIDA.

Anthea.

Fig. 33.

Actinia Tuediie, Johnston in Mag. Nat. Hist. v. 163, fig. 58 ; and Trans.

Newc. Nat. Hist. Soc. ii. 246 Anemonia edulis, Risso, L'Europ.

Merid. v. 289.

Hab. Coast of Berwickshire, in deep water.

Anthea Tuedise is amongst the largest of our species. The body, when relaxed, generally measures three inches in length, and about the same in diameter ; it is of a uniform reddish or brownish-orange colour, and either smooth or contracted at pleasure into circular folds. The base is smooth and oi-ange- coloured, with a thin areolar skin. The mouth is ever varying in size and form, and there are often pro- truded from it vesicular-like lobes of a reddish colour scored with fainter lines. When fully expanded, the oral disk is not less than four inches across ; there is a smooth space between the mouth and tentacula, which are very numerous, and placed in several rows ai'ound the circumference ; those of the inner row are larger than the others, measuring frequently two inches in length, and they become gradually shorter in the exterior series. They are of a chesnut or reddish flesh colour, often darker coloured towards the bases, but never variegated with rings of different hues, thick and clumsy, ta- pered to an obtuse point, marked longitudinally with distinct lines or impressed striae, tubular, perforated at the ends, and constricted at their insertions. The creature has no power of withdrawing them within the oral aperture, nor does it seem capable even of shortening them in any considerable degree, but it twists them in a wreathed or spiral form, or gives the whole circle a greater or less degree of ex- pansion.

Actinia.. Z. HELIANTHOIDA. 223

The trivial name which I have bestowed on this species is intend- ed to indicate the place of its first discovery, Tuedia being, according to Sir Robert Sibbald, the ancient name of the maritime parts of Ber- wickshire. It is not uncommon on that coast, but is found only in deep water, whence it is dragged up by the fishermen. I have often found the tentacula, in a separate state, adhering to their lines ; and as these retain their irritability and motion for a long time, they are apt to be mistaken for independent and perfect worms, which they much resemble.

Dr Turton has introduced into his Compendium of the British Fauna, p. 131, two species which I purposely omit. These are, I. Actinia Caryophillus,* for which " Martin's Marine Worms" is quoted, a work apparently very rare, and which 1 have not been able to procure ; 2. A. ANEMONOiDp;s,f quoted from Shaw's Natura- list's Miscellany, tab. 26, 27. The plates referred to I have not seen, but I have looked over some volumes of the work, and I entirely agree with Dr Leach in thinking it contemptible and unworthy of ci- tation : the figures are in general copies from others, coloured from the descriptions, without a single hint being given that this is the case, and the colours are laid on in a patched and gaudy manner, only to be rivalled in the pictures which adorn the toy-books of children.

Observations. The Actiniae adhere to rocks, shells, and other extraneous bodies by means of a glutinous secretion from their enlarged base ; but they canleave their hold and remove to another station whensoever it pleases them, either by gliding along with a slow and almost imperceptible movement,:}: as is their usual method ; or by revei'sing the body and using the tentacula for the purpose of feet, as Reaumur asserts, § and as I have once witnessed ; or lastly, inflating the body with water to render it more buoyant, they detach themselves and are driven to a distance by the random motion of the waves. They feed on shrimps, small crabs, whelks, and similar shelled mollusca, or, probably with indifference, on whatever animals are brought within their reach, and whose strength or agility is insufficient to extricate them from the grasp of their numerous tentacula, for as these organs can be inflect-

* Stew. Elem. i. 394. Turt. Gmel. iv. 103. Pe7i. Brit Zool. iv. lOG.

f Tnrt. Gmel. iv. 101. Act. anemone, Pen. Brit. Zool. iv. 106.

I Reaumur found that they require an hour to advance one or two inches . but I have seen A. Mesembryanthemum advance at a rate considerably quicker — half an inch in about five minutes.

§ Mem. de I'Acad. Roy. des Sc. 1710, p. 621.

224 Z. HELIANTHOIDA. Actinia.

ed in any direction and greatly lengthened, they ai'e capable of being- applied to every point, and adhere by suction with considerable tena- city. * The food is retained in the stomach for ten or twelve hours, when the undigested remains are regurgitated, enveloped in a glairy fluid, not unlike the white of an egg. The size of the prey is fre- quently in unseemly disproportion to the preyer, -j- being often equal in bulk to itself. I had once brought me a specimen of Act. gemmacea, that might have been originally two inches in diameter, and that had somehow contrived to swallow a valve of Pecten maxi- mus of the size of an ordinary saucer. The shell, fixed within the stomach, was so placed as to divide it completely into two halves, so that the body, stretched tensely over, had become thin and flattened like a pancake. All communication between the inferior portion of the stomach and the mouth was of course prevented, yet instead of emaciating- and dying of a hytrophy, the animal had availed itself of what undoubtedly had been a very untoward accident, to increase its enjoyments and its chances of double fare. A new mouth, fur- nished with two rows of numerous teutacula, was opened up on what had been the base, and led to the under stomach : — the indivi- dual had indeed become a sort of Siamese twin, but with greater in- timacy and extent in its unions I

The existence of nerves in the structure of the Actiniae is still doubtful. Spix tells us, that he detected near the base and centre of the body some small nodules or ganglions jjlaced in pairs, from which filaments emanate towards the circumference, constituting, as he be- lieves, their nervous system. Blainville asserts, however, that in numerous dissections made with every possible care, he could see nothing like what Spix has described and figured ; and the only part that he can regard as nervous, is a sort of grey pulpy cord in the margin of the labial rim. Delle Chiaje, and Mr Teale agree with Blainville.J Be the fact as it may, we know that every part of the

* According to Gaertner the animal fixes the tentacula by throwing out of their whole surface " a number of extremely minute suckers, which, sticking fast to the small protuberances of the skin, produce the sensation of a roughness, which is so far from being painful, that it even cannot be called disagreeable." Phil. Trans, v. 52. p. 76. — No such structure can be discovered.

f " Fauces hsec animalia, subtus sacci instar penitus clausa, superne habent

pro libitu tam patulas, ut mytulos satis magnos aliasve conchas ingurgitent, e

quibus, modo nos fugiente, pisces extrabere, et evacuatas testas per eandem

aperturam, ejicere riursus valent Quae testte, si majores sint, et segre per fauces

transituras essent, Priapus non solum fauces late expandit, sed easdem, ut so-

lemus tibialia, quasi invertit, quo spatium brevius et apertura fit latior." Bas-

teri Opusc Subsec. i. lib. iii. 122.

\ But Dr Grant says — " The nervous system has been long known in the

4

AcriNi.i:. Z. HELIANTHOIDA. 225

body is very sensible to external irritations : no point of the skin, the tentaciila, nor the membrane of the stomach can 1)C touched, but immediately the creature evidences its sense of the injury by contrac- tions and other motions of the part. They are said also to be very sensible of atmospherical changes : they shrink under a glare of light;* but in a calm and unclouded sky expand and disclose every beauty, while they remain contracted and veiled in cloudy or stormy weather. Dicquemare has even found, from several experiments, that they foretell changes in the weather as certainly as the barometer : when they remain naturally closed there is reason to fear a storm, high winds, and a troubled sea ; but a fair and calm season is to be antici- pated when they lie relaxed with spread-out tentacula. f

Actinia." — " Nervous filaments surround the muscular foot of the Actinia, be- neath the stomach, and present minute ganglia in their course, from which nerves pass out to the circumference, and to the muscular folds which here possess great power of contraction. The same system probably exists in many other closely allied forms of polj-pi." Outl. of Comp. Anat. p. 182.

* It has been suggested that their perception of light may be communicated through the tentacula, on the tips of which, Bosc assures us, there is a black point or eye. Vers, Vol. ii. p- 247. This black point, as well as the other parts of Bosc's description of the tentacida, is wholly imaginary ; nor is there a necessity of an eye to explain the phenomena, for there can be " little doubt that a dif- fused sensibility to light and sound exists in animals which present no special organs of vision or hearing." Brit, and Foreign Med. Rev. v. p. 491.

f Dicquemare's observations seem of sufficient interest to justify their insertion at length. He says, " My very earliest observation showed that the sea ane- monies feel and prognosticate, within doors, the different changes of tempera- ture in the atmosphere. I had not leisure at that time to form tables of their various indications, but I have since done it. This fact, if applied to practice, might be of use in the formation of a sea-barometer, an object of no small im- portance, which several ingenious men have hitherto endeavoured in vain to furnish us with. I should prefer the anemonies of the third species for this pur- pose, their sensation being very quick ; they are also easily procured, and may be kept without nourishment. Five of them may be put in a glass vessel, four inches wdde and as many in depth, in which they will soon cleave to the angle formed by the sides and the bottom. The water must be renewed every day, and as they do not require a great quantity of it, as much may be fetched from the sea (if they be kept on land) as will supply them for several days ; its settling some time will only improve it- If the anemonies be at any time shut or contracted, I have reason to apprehend <m approaching storm, that is high winds, and an agitated sea. When they are all shut but not remarkably contracted they forebode a weather somewhat less boisterous, but still attended with gales and a rough sea. If they appear in the least open, or alternately and frequently opening and clos- ing, they indicate a mean state both of winds and waves. When they are quite open I expect tolerable line weather and a smooth sea. And lastly, when their

P

226 Z. HELIANTHOIDA. Actini.t^.

That the Actiniae are vivijiarous is very commonly alleged, and almost every naturalist who has paid attention to their habits may he quoted as a witness of the escape of the young from the stomach through the oral aperture. * Some have maintained that these young may have been swallowed accidentally by the supposititious mother, and being found unfit for digestion are consequently rejected, quoting in favour of this not very feasible conjecture, an experiment of Dicquemare, who, offering several small individuals to a larger one of a different species, found that it swallowed them readily, " but threw them up again alive within eight, ten, or twelve hours, or even later." Dicquemare himself, although he expresses himself in dubious terms, evidently believed them to be viviparous, having seen several bring forth even in his hand, eight, ten, or twelve young ones like to their parents in all but size, and which iiTimediately affixed themselves, and began to stretch their tentacula as if in quest of prey. Ellis was of the same belief ;f and Sir J. G. Dalyell, the best authority on the subject, also says that they are viviparous. " The embryos, one or more, appear firstin the tentacula, from whence they can be withdrawn and transmitted to others by the parent, and are at last produced by the mouth. In the course of six years, a specimen preserved by the author, produced above 276 young ; some pale, and like mere specks, with only eight tentacula, others florid, and with twenty. They are fre- quently disgorged along with thehalf-digested food, thirty-eight appear-

bodies are considerably extended, and their limbs divergent they surely prognos- ticate fixed fair weather and a calm sea. There are times when some of the anemonies are open and others shut ; the number must then be consulted, the question is decided by the majority. The anemonies used as barometers should not be fed, for then the quantity of nourishment might influence their predic- tions. Anemonies of this and of the first species live and do well for several years without taking any other food but what they find disseminated in the sea water ; but should a respite of some days be granted them, they might then be fed with some pieces of muscles of soft fish, and thus restored to their original vigour. Whenever the vessel is sullied by the sediments of salts, slime, the first shoots of sea plants, &c. it may on changing the water be cleansed by wp- ing it with a soft hair pencil, or even with the finger, carefully avoiding to rub or press hard on the anemonies. Should any of them drop off during this opera- tion, they may be left at liberty, for they will soon of their own accord fix them- selves to some other place. Should any of them die, which will soon be disco- vered by the milky colour of the water, and an offensive smell on changing it, it must be taken out, and on the first opportunity another of the same species be put in its place ; those of a moderate size are the most eligible." Dicquemare in Phil. Trans, abridg. xiii. G42-3.

* " Leur generation ordinaire est vivipare. Les petites actinies passent de I'ovaire dans lestomac et sortent par la bouche." Cuvier, Reg. Anim. iii. 291.

t Phil. Trans. Ivii. 429.

3

AcTiNi/E, Z. HELIANTHOIDA. 227

ing- thus at a single litter. An embryo extracted artiricially from the amputated tip of a tentaculum, began to breed in fourteen months, and survived nearly five years. Monstrosities by excess are not uncom- mon among the young : one produced naturally, consisting of two perfect bodies, and their parts sustained by a single base, exhibited embryos in the tentacula at ten months, bred in twelve, and lived above five years. While one body was gorged with food, the other continued ravenous."* These facts are to be explained on the siip- position that the ova have been detained and developed in the inter- septal spaces, for it is very well ascertained that the creatures are truly oviparous. The ovum, under oi'dinary circumstances, is recog- nizable as the young of an Actinia about twenty days from the

Fig. 34.

time of its separation, f It has at first very few tentacula, — from four to twelve, arranged in a single row, but they gradually germi- nate in greater numbers, and arrange themselves in two or more im- perfect circular series ;J — a fact which strikingly illustrates the futili- ty of that classification which mainly rests the distinction of its ge- nera upon the number of these circles. §

The Actiniae are very patient of injuries, and rival the Hydra in their reproductive powers. They may be kept without food for up- wards of a year ; they may be immersed in water hot enough to blister their skin, or frozen in a mass of ice and again thawed ; and they may be placed within the exhausted receiver of the air pump, without being deprived of life, or disabled from resuming their usu- al functions when placed in a favourable situation. If the tenta- cula are clipped off they soon begin to bud anew, and if again cut away they grow again, so that " it seems these reproductions might ex- tend as far, or be as often repeated as patience and curiosity would admit." If cut transversely through the middle, the lower portion of

• Rep. Brit. Assoc, an. 1834, p. 599 ; and Edin. New Phil. Journ. xvii. p. 411.

f Dalyell in Edin. New Phil. Journ. xxi- p. 89, 90.

\ Dalyell in Edinburgh Encyclopaedia, art. " AnimfU Flower," p. 1.32. Tem- l)leton in Mag. Nat. Hist. ix. 303 ; and Harvey in ibid. n. s. i. p. 474.

§ Brandt. A Synopsis of his System is given by Blainville. Actiuologic, p. 066.

228 Z. HELIANTHOIDA. Lucernaria.

the body will after a time produce new tentacula " pretty near as they were before the operation ;" while the upper portion swallows food as if nothing had happened, permitting it indeed at first to come out at the opposite end, "just as a man's head being cut off, would let out at the neck, the bit taken in at the mouth," but which it soon learns to retain and digest in a proper manner. In an experiment of this kind, the upper half, instead of healing up into a new basis, actually produced another mouth and tentacula, so that an animal was formed which caught its prey, and fed at both ends at the same time! If again the section of the body is made in a perpendicular direction so as almost to divide it into two halves, these halves unite again in a few days. If the section is complete, two perfect individuals is the result ; and to complete the wonder, if the body is torn away and only a portion of the base remain, from this fragment a new offspring will sometimes rise up to occupy the place of its parent !* Yet these creatures, almost indestructible from mutilation and injury, may be killed in a few short minutes, by immersion in fresh water.

21. LucERNARiA,f Muller. Character. Body somewhat campanulate,Jixed lohen at rest hy a narrow disk or stalk : mouth quadraiiyidar, hi the centre of an nmhrellar expansion : tentacida disposed in ^cide1y separate tufts on the margin.

1. L. FASCiCULARis, ^^ peduncle of the body produced : tuft of tentacula in pairs^ ahoid a hundred in eachj" Rev. Dr Fleming. Lucernaria fascicularis, Fleming in Wern. Mem. ii. 248, pi. 18, fig- 1, 2. Flem. Brit. Aiiim. 499. Templeton in Mag. Nat. Hist. ix. 304. Blainv.

Actinolog. 664. Lucernaire fasciculaire, Lamouroux in Mem. dii

Mus. ii. 470. Hah. Common in Zetland, where " it is chiefly found on the leaves of Fucus digitatus and F. esculentus, which grow in deep water," Fleming. " Found on the coast at Donaghadee, after a strong east- erly gale, adhering to a fragment of Fucus serratus," Templeton.

" Colour dark brown ; peduncle cylindrical, flexuous, wrinkled, with a narrow base ; body bell-shaped, subquadrangular, concave ; margin divided into four pairs of arms, concave within ; mouth cen- tral, tubular, consisting of a loose membrane, four notched at the tip,

* Dicquemare in Pliil. Trans, abridg. xii. 640, &c. ; xiv. 129. Yet, accord- ing to the same excellent naturalist, a wound or rent of the basis of an Actinia often proves falal. xiii. 637.

f F'l'ou) Lucerna, a himp.

LUCERNAIUA.

Z. HELIANTHOIDA.

2:20

and also expanded, circular, or striated at the pleasure of the animal ; the inside with numerous white filaments." — " The animal contracts itself into various shapes. It moves the tentacula very quickly, espe- cially if muddy water is poured upon it. Although I have kept it alive several days, I have never observed it in an upright position. It in general hangs downwards, as expressed in the figure, sometimes,

however, it is nearly horizontal." Fleming. " When at rest, it

assumes very much the form of a common drinking-glass, and is ex- ceedingly conspicuous from its beautiful rose tint." Templeton.

2. L. AURICULA, body sessile, cMinpanulate ; tufts of tentacula 8, equidistant, with a marginal tubercle between each pair. G.

Montao-u.*

Fig. 35.

Holothuria lagenam referens tentaculis octonis fasciculatis, Mull. Zool.

Dan. prod. 232, no. 2812 Lucemaria auricula, Fabric. Faun. Groenl.

341. Tvrt. Gmel. iv. 121. Montagum Lin. Trans, ix. 113, pi. 7, fig. 5. Penn. Brit. Zool. iv. 1 10. Flem. Brit. Anim. 499. Johnston in Mag. Nat. Hist. V. 44, fig. 29 ; and in Trans. Newc. Soc. ii. 248. Templeton

in Mag. Nat. Hist. ix. 304. L. octoradiata. Lam. Anim- s. Vert. ii.

474. L. auricule, Lamour. in Mem. du Mus. ii. 471.

llab. Coast of Devonshire, Montagu. Adheres to Fuci, near low- water-mark, on different parts of the coast, Fleming. " Found ad- hering to the Fuci on the shore at Ballycastle, and in the cave near

* George Montagu, Esq. F. L. S. the autlior of " Testacea Britannica," and of a much valued Ornithological Dictionary. His contributions to the history of invertebrate animals were also numerous, and always interesting : the best, perhaps, is his Essay on Sponges in the Wernerian Memoirs. He is often styled Colonel Montagu, probably being the commander of some volunteer corps. He died at Knowle House, his residence, near Kingsbridgc, Devonshire, on June 1 9, 1815, in the 76th year of his age, from tetanus produced by a wound in his foot from a nail. Annals of Pliilosophy, vi. p. 77. His collections are now in the British Museum. F'or an estimate of his rliaracter sec Fleming's Brit. Animals, Pref. p. X.

230

Z. HELIANTHOIDA.

LuCERNARIA.

Dunluce Castle, county Antrim, in great numbers ; July 1815," Tern- pleton. Berwick Bay, rare.

Our figures represent this beautiful animal in its natural size. The individuals from which they were drawn were of a clear pinkish red colour, but Montagu says that it is " pellucid, green, brown, purple, red, or yellow, and all the intermediate shades in different subjects." It adheres by a short stalk, cupped in its base and variable in its de- gree of distinctness, dilating into a sort of campanifonn blossom, the margin of which is set round usually with eight short processes or arms, each of them terminated with a globose tuft of about sixty glandu- liferous filaments, (Fig. 36, a.) The arms are mottled with two rows

Fig. 36.

of spots, occasioned by the ova (6) ; and they are connected together by a thin transparent membrane. Between each pair there is an oval vesicle (c) placed on the edge of this membrane. Lamouroux asserts, apparently on the authority of Ch. Muller, that this vesicle appears only at certain seasons, and again disappears, — a statement which re- quires confirmation. The mouth forms a slight quadrangular pro- jection in the centre of the cupped expansion, exactly opposite the contracted base.

In the specimens which furnished the vignette to this order (Fig. 28,) there were nine glanduliferous tufts ; and Montagu's figure re- presents a monstrosity with seven only, but as there is no appearance of marginal tubercles in it, the figure may belong to the following

LUCEKNARIA.

Z. HELIANTHOIDA.

231

species. Otho Fabricius tells us — " Vescitur oniscis, praesertim onisco ahyssino, quern semper fere solum in ventriculo ejus inveni ; raro in majoribus squilla lobata occurrit. Hi miseri in aperturam corporis (lilatatam oft'endentes, statim tentaculis concludentibus capiuntur et ingurgitantur. — Saepe in uno verme plures oniscos invenire contigit, interioribus corruptis, exterioribus adhuc integris." — Otho Fabricius.

3. L. CAMPANULATA, hody suhsessHe, campanulate ; tufts of tcvtacula 8, equidistant, icithout intermediate marginal tubercles, Dr John Coldstream.*

Fig. 37.

■ Lucernaria campanulata, Lamouroux in Mem. du Mus. ii. 472, pi. 16, fig.

1 — 7. L. Convolvulus, Johnston in Mag. Nat. Hist. viii. 59, fig. 3.

Lucemaire auricule, Blainv. Actinolog. pi. 30, fig. 4.

Hub. On sea-weed near low-water mark. Torbay, Dr Coldstream. Berwick Bay, G. J.

About an inch in height ; of a uniform liver-brown colour, smooth, adhering by a circular disk, above which there is a deep stricture or short peduncle : the disk even, strengthened by an interior cartila-

* A native of Leith, where he is now settled as a physician. Dr C. is an alumnus of the University of Edinburgh, and graduated M. D. in 1827 ; his Thesis being " de Indole Morborum periodica." He early distinguished him- self by rcseaiches in Meteorology and Zoology, more particularly by his essays on the chromophorous globules of the Cephalopoda, and on Limnoria terebrans.

232 Z. HELIANTHOIDA. Lucernaria.

ginous lamina which rises up the short peduncle, and forms a minute hollow firm centre. The margin of the oval expansion is somewhat thickened, and divided into eight equal arms, each furnished with a tuft of numerous short tentacula tipped with a gland, and brighter coloured than the body. The interior is hollowed like the blossom of a flower, the square extensible mouth projecting in the centre ; and in the space between the arms there is a complicated structure composed apparently of two series of foliaceous processes arranged on each side of a white line that seems to spring from the sides of the mouth. These processes are formed by the complicated foldings of a thin membrane attached by one side in the manner of a mesentery ; there are no vessels in the membrane, but some portions of it exhi- bit, when magnified, a kind of net-work of irregular cells, and the outer and free edge is bounded by a thread-like line. The white cen- tral line which divides them is formed of small roundish bodies ar- ranged in two or three close series ; and some of these ova can at times be traced along the margin of the circumference to the tenta- cula. The latter are cylindrical and terminated with a globular head, which is seemingly imperforate. The stomach is a loose thin plait- ed extensible bag, having attached to its inner surface numeroiis fili - form CBRca, (Fig. c) that, after their removal from the body, retain their irritability for a long time, and writhe themselves like a knot of worms. — Dr Coldstream has favoured me with the following obser- vations on the habits of this Lucernaria. — " I find the animal very hardy. It is constantly in a state of expansion, and does not contract excepting when very rudely handled. One specimen has lived with me for three weeks although the water has not been very often changed. When 1 first procured it, the two rows of spots running from the mouth along each arm were prominent, and of a dark red- dish-brown colour. Since that time they have increased in size, and have become studded with numerous white oval bodies which I sup- pose to be ova. I see some of these have made their way into the web connecting the arms, but I have not observed any expelled from the body."— 5th April 1833.

Observations. The Lucernarise are of a gelatinous consistence. The skin or co- rium is smooth and thickish. After covering and giving form to the body it is reflected over the oral disk, and encloses, within the du])li- cature formed by this reflection, the internal viscera. The body is more or less distinctly campanulate, and is prolonged inferiorly into a pedicle, very variable in length, which has its bottom conformed into a small sucker. From this point four ligaments, probably of a

4

LvcERHAiuJF.. Z. HELIANTHOIDA. 233

muscular nature, rise up within the peduncle, dividing at the expan- sion of the l»ody, into eight distinct fasciculi, one proceeding to each arm. These fasciculi are composed of long parallel fibres, are analo- gous to the lamella} of the Actinia), and like them divide the body into eight equal compartments, for the inner fold of the corium is in- timately connected with them on both sides. The vermiform caeca lie in these compartments ; and the ova appear also to be generated in them, but whether they have an appropriate ovary is doubtful. A specimen which had undergone a certain degree of putrefaction and dissolution exhibited these ova forming a complete circle round the mouth with rows running up the arms to the base of the tentacula. (Fig. 36.) The ova were proportionably large, roundish or oval (Fig. 36, d), and irregularly grouped. The change produced in the appear- ance of the tentacula was considerable, for the globular apex had dis- appeared, and all had assumed a linear or conical figure (Fig. e), — the centre filled with an opake granular matter forming a dark speck at the apex, and covered with a clear mucous skin. The vesicle pre- sented precisely the same structure, but no apertui'e was visible in either part.

The Lucernarise can swim with some rapidity in the water by al- ternate dilatations and contractions of the body, but they are usually found adherent to sea-weeds, the first species in a dependent position, the two latter invariably erect, so that Lamarck is in error when he describes the mouth as being inferior. When in a state of expan- sion, few marine worms exceed them in beauty and singularity of form ; when contracted they are shapeless and easily overlooked. They feed on small crustaceous animals brought within reach by the tide or their own destiny,* and to arrest them more certainly the ten-

" Lamouroux asserts that L. campaniilata perceives its prey wlien within a short distance and pursues it. His words are — " J'avois la precaution de chan- ger I'eau de mes Lucernaires deux fois par jour ; dans un vase qui ne contenoit qu'un de ces animaux, ce dernier executa des mouvements qui me parurent ex- traordinaires dans un etre d'un consistance aussi molle, immediatement apres que j'y eus de I'eau nouvelle ; avec la loupe je m'aper^us que ces mouvcmens etoient causes par la presence d'un animalcule que la Lucernaire sembloit i)ur- suivre en se portant a droite et a gauche, pour taclier de le saisir ; toutes les fois qu'il s'eloignoit a la distance d'environ lui pouce, la Lucernaire cessoit tout mouvement ; s'il se rapprochoit, la chasse recommen9oit de suite, et les mouve- mens etoient vifs et prompts : I'animalcule fut enfin saisi par les tcntacides d'un dcs rayons, qui a I'instant se replie vers la bouche ; les autrcs rostercnt tou- jours etales ; ce rayon reprit pen a pen sa position ordinaire, M'utant procure d'autres animalcules, je les donnai a mes Lucernaires, et j'cus le plaisir de voir leurs mouvemens se repcter avec les memes circonstances." Mem. du Mus. ii. 4G4.

234 Z. HELIANTHOIDA. Lucernari;e.

tacula are widely displayed ; but no sooner have they felt the prey than they instantly contract, envelope it in their joint embrace, and carry it to the mouth by an involution of the whole marginal cir- cumference. I have found that the glands with which the tentacula are tipped pei'form the office of suckers, as Lamarck conjectured, and thus retain their captives with greater certainty ; but if Dr Fleming's figure of L. fascicularis is correct, its tentacula are not glauduli- ferous.

" O Lord, how manifold are thy works ! in wisdom hast thou made them all : the earth is full of thy riches : so is this great and wide Sea, wherein are things creeping innumerable, both small and great beasts." — Psalmist.

BRITISH ZOOPHYTES.

PART V.

ZOOPHYTA ASCIDIOIDA.

Fig. 38. b

Lagenella repens.

" How many animals, whose middle part

" The sharpest eye

« Can't see ?

" How subtle then the guts, the heart, the eye I

" How thin each little member of the whole !"

Lucretius, s. Creech.

" Aiiisi poiu- I'espece humaine on peut dire que les Zoantliaires ne sont utilos que comme moyen philosophique. Ce sont en effet des animaux fort remar- quables sous ce rapport, et dontla connoissance a introduit des considerations tres interessantes dans la science de la vie." — H. M. D. De JBlainville.

" Combien on a eu tort de negliger, dans la recherche des lois de la vie, I'etude de ces etres microsoopiques que Ton se contentait de releguer dans le domaine des ainusemens et des petites recreations physiques, comme si, dans les profondeurs de la nature, il existait de petit autre chose que les petits esprits !" — M. Raspail.

" O how desirable are all His works ! and that a man may see even to a spark. All these things live and remain for ever for all uses, and they are all obedient- All things are double one against another : and He hath made nothing imper- fect. One thing cstablisheth the good of another : and who shall be filled witli beholding His glory." — Ecclesiasticus.

ZOOPHYTA BRITANNICA.

ORDER IV.

Z. ASCIDIOIDA. *

Character. Polt/pes aggregate^ the mouth encircled with filiform ciliated retractile tentacula ; a distinct stomach, with a curved intestine terminating in an anus near the mouth ; ova internal. — Polypi- dams very variable, — either horny fistidar and confervoid, or cal- careous, membranous, or fibro-gelatinous, formed of cells connected and arranged in a determinate and usually quincuncial manner.

Observations. In the preceding orders we found reason to conclude that the polypidom of the Hydroida was a sheath disconnected, or at least not in organic union, with the soft pulpous matter which it invests and protects ; that the corresponding part in the Aste- roida, become an interior siieleton or axis, held the same rela- tion to itspolypiferous crust; nor was this relation altered when the polypidom had again, in the Helianthoida, assumed an ex- ternal position, forming an integral part of the epidermis. In all these instances the polypidom. appears to be unorganized, and when once formed, beyond the reach of change from either the polypes or its own inherent powers ; -f- but in the present

* This order corresponds with the Polyzoa of Thompson, the Bryozoa of Ehrenberg, the Bryozoaires of Milne- Edwards, and the Ciliobrachiata of Farre. Our order Hydroida Farre designates Nudierachiata, thereby indicat- ing the absence of cilia on the tentacula ; aiid Milne- Edwards les Sertulai- RiENS. His Alcy'oniens is synonymous with our Asteroida ; and the Zoan- taires with Helianthoida, but Farre unites these under the name of Antho- ZOA, borrowed from Ehrenberg.

•\- " Unorganized non-vascular parts are produced by an organized matrix, and grow by the continued deposition of new matter on one surface." Miiller's Elements of Physiology, p. 384.

238 ZOOPHYTA ASCIDIOIDA.

order, the cell, although pre-eminently entitled to the name of polypidom from its appearance and use, is a living portion of the animal which it seemingly contains. The cell is in fact the outer tunic of the polype, analogous to the envelope of the com- pound mollusca, endowed certainly with no very sensible or active properties of life, yet in organic connection with the interior parts and liable to organic changes. The relationship in which they stand to one another is nearly, if not precisely, the same as that which the fleshy crust of the Asteroida bears to its polypes, as a comparison of the Alcyonium with the Alcyonidium or Al- cyonella will render sufficiently plain ; and it is not less real even in those genera where the cells, when dried, have hard calcareous and apparently impermeable parietes. For the proof of this fact, — a very important one in their physiology, and in any question touching their rank in the animal kingdom, — na- turalists are principally indebted to Milne-Edwards, and I can- not do better than lay his arguments in its behalf before the reader in a translation of his own words. * The connection is effected by means of an inner tunic which, after enclosing the polype's body as in a pouch, is afterwards reflected over the aperture of the cell, — the reflected portion becoming exterior and solidified either by calcareous depositions in its texture, or by a mutation of its thin membranous character into a horny investment better suited to the office it has now to perform of pro- tecting the sentient body from a too rough contact of the medium in which the animals live, and from worser foes. From this mode of connection it results that when the polypes retire within, they at the same time must close the aperture to their cells, for that portion of the inner tunic which is pushed outwards by their exit, in their withdrawal follows the body by a process of invagi- nation, becoming at one and the same time a sheath for the column of tentacula, and a ])lug to the aperture, which, when of a flexible material, has its margins also drawn tighter and closer together.

The polype which endues itself with this cell is widely diff'er- ent from any previously described ; and in a system that should pretend to arrange animals according to their agreements in or- oanization, could not be placed in one common class. Be-

• See Additional Note, No. 4.

ZOOPHYTA ASCIDIOIDA. 239

tween the polypidoms there is an apparent affinity. The Crisiadoe are not unhkc the Sertuhiriacla?, and it is still disputed whether some Gemmicellariyo appertain to this family or to the Flustra ; the resemblance between the Sertularite and the Vesiculariadse misled even Lamarck to their union under one genus ; and their names would seem to imply that the framers of the genera Al- cyonidium and Alcyonella believed them to be in a family re- lationship to Alcyonium. These are examples which prove the fallacy of outward characters ; and how darkly the naturalist must grope his way who would walk through Nature's labyrinth without the ariadnsean thread that the anatomist alone can give him ! In the instance before us he has demonstrated that the resemblances indicated above imply no propinquity in their ob- jects. The ascidian polypes the Creator has cast in the mould — not of the radiata — but of the mollusca, — yet with such a con- siderable variation as to mark their ordinal distinctness ; for the Mollusca Tunicata — their nearest allies — are not protrusive from their cells as these polypes are ; and this seeming slight dis- crepancy connects itself, perhaps of necessity, with a total change in the position and nature of their respiratory organs. Interior and immotive in the one tribe, they line, in a reticular pattern, the parietes of a sac capacious enough to contain a sufficiency of the aerating fluid ; while in the other they clothe the exsertile ten- tacula in the form of cilia which must be placed outwards amid the circumfluent waters before they can play and fulfil their func- tions.

Notwithstanding the great diversity in the forms of the poly- pidoms of this order, there appears to be a very remarkable uni- formity in the habit and structure of the polypes. The body lies doubled up in the cell (Fig. 39, a, b.), its oral extremity crowned with a circle of lono- filiform ciliated tentacula.* From the centre of this circle the mouth opens into a sort of pharynx (Fig. 39, a, 1.) which begins the cesophageal tube, generally of

* At page 34 the tentacula of the Ascidioida are stated to be solid .• an error which Dr Farre enables us to correct. In Alcyouidium, " with an amplifying power of 200 linear," " they are seen to be (ubular throughout, and to have an aperture at each extremity; (hat nt the base apparently communicating with a fine canal round the oral rim, which probably unites the tentacular canals into one circle." Phil. Trans, an. 1837, p- 406. This is a structure very like that in the two preceding orders.

240 ZOOPHYTA ASCIDIOIDA.

considerable length, and studded, especially at the upper part, with minute oval spots arranged in close contact with each other. The whole tube appears to be highly irritable, and contracts vigorously when food is introduced into it. "At the termi- nation of the oesophagus is a distinct cardiac orifice (a, 2.) that opens into a small globular cavity of singular construction, which appears to perform the office of a gizzard, (a and b, 3.) The parietes of this organ are thicker than in any other part of the alimentary canal. They contain two dark round bodies placed opposite to each other, from each of which dark lines are seen radiating." In the space between these bodies may be seen a number of scales grouped in a close, regularly tessulated man- ner, which line the inner surface of the cavity, and probably serve the office of gastric teeth, having their motions regulated by the muscular fibres whose disposition is indicated by the dark

radiating lines.

The o-izzard,*or when it is absent (which proves to be the case in many oenera), the oesophagus, opens downward into the true digestive stomach, (a, 4.) from which it is separated only by the contraction of the parietes. This stomach is usually of an ob- long shape, and its walls are thickly studded with spots of a rich brown colour, — apparently hepatic follicles that secrete a fluid which often tino-es the whole organ, as well as its contents, of a similar hue. — " From the upper part of the stomach, and by the side of the entrance from the gizzard, arises the intestine {a, 6.) by a distinct pyloric orifice (a, 5.) that is surrounded by vibratino- cilia. The intestine passes up straight and narrow by the side of the oesophagus, from which it is entirely separate and free, and terminates by a distinct anal orifice {a, 7.) in the deli- cate parietes of the body, close to the outer side of the tentacu- lar rino-. The parietes of the intestine are marked with pale spots, something like those of the pharynx, and the whole tube, like the rest of the alimentary canal, possesses a high contrac- tde power. Thus the alimentary canal consists of pharynx or oesophagus, gizzard, stomach and intestine, with subsidiary se-

* Compare this with a somewhat similar structure in the planarian worms which I have phiced in the genus Nemertes. Mag. of Zool. and Bot. Vol. i. p. 530. pi. 17, fig. 5.

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ZOOPHYTA ASC'IDIOIDA. 241

creting follicles, and distinct oral, cardiac, pyloric, and anal ori- fices. The whole floats freely in a visceral cavity, the bound- aries of which are formed by the delicate transparent parietes of the animal ; the space between the alimentary canal and the parietes being occupied by a clear fluid, and by the muscles which act upon the animal."*

Let us now suppose that the polypes are in a state of extru- sion and fully expanded, as represented in Fig. 39, a ; all the cilia in play, and the water whirling in rapid streams up and down the opposite sides of the tentacula, carrying with them nutri- ment and the breath of life. All is quietness and security around, and the little creatures are evidently in a state of hap- piness and enjoyment : no one who has witnessed the micro- scope scene, — the myriads of the little flosculous heads that pullulate and blossom over the entire polypidom, as thickly peopled as the swarming hive, can have any doubt of this,-}- es- pecially when he remarks the acuteness and vivacity of their sensibilities and actions, for, under his eye, one will ever and anon suddenly sink out of view, hide itself within the cell, again on a sudden emerge and expand, or, it may be, lay itself down in repose and concealment, until digestion has freed it from a state of repletion, or forgetfulness has removed the alarm of an enemy.:}: These positions are assumed with such a rapidity that the eye cannot trace the steps of the process ; and large glasses and minute skill are required to reveal to us its mechanism.

• Farre in lib. cit. p. 393.

t " The heart is hard in natm-e,

that is not pleased

With sight of animals enjoj'ing life, Nor feels their happiness augment his own."

Cowper- \ " No trace of either nerves or ganglia could be detected ; yet the attributes of a nervous system were so clearly exhibited as to leave no doubt but that this must exist, and probably in some degree of perfection. Not only was the deli- cacy of their sense of touch very strongly marked, but the operations also con- sequent upon the enjoyment of such a sense were sometimes singularly striking. This is seen in the instant retiring of the animal on the slightest alarm, and the caution which it sometimes shows before emerging again from its cell ; in the obvious selection of its food ; and in the pertinacity with which it refuses to ex- pose itself to water that has become in the least degree deteriorated." — Farre in Phil. Trans, an. 1837, p. 414.

242 ZOOPHYTA ASCIDIOIDA.

The polype then is expanded and wishes to sink within its cell. To answer this wish two distinct sets of muscles are provided, the one acting upon the animal, and the other upon the flexible part of the cell, or, in other words, on that portion of the inner tunic which has been carried outwards in the polype's egress. The former set originate from the bottom of the cell («, 8,) and from the sides near the bottom (ar, 9) ; whence trending upwards, they are inserted into the stomach, and into the pharynx and tentacular ring. It is obvious from this position, that their con- traction will draw the whole body down in the cell, where it lies doubled up in the form of a letter S, that all its parts may be brought within the compass of its house. The other set of muscles for the retraction of the flexible portion of the cell, or operculum, have their origin from the inner surface and near the top of the fixed immotive part, and are inserted into the piece on which they act ; (Fig. b, 2, 3,) so that when the first set have partially done their duty, the second follow up the process by pulling after the sinking body the flexible membrane, inverting it at the same time as we undo a stocking from the leg ; and as the last result, closing the aperture or fixing the operculum down upon it.

To replace the polype in its external relations a very diffe- rent mechanism is brought into play. The inner tunic of the cell, or that which immediately invests the body and encloses the viscera as in a sac, appears to be susceptible of changes in its capacity from the action of some muscular fibres that run in a transverse direction through it. When the polype lies perdue, the sac is distended and the muscles relaxed, but on their con- traction the capacity of the sac is reduced ; and the body, pressed upon on all sides, must of necessity rise upwards in that direction in which it is most free to move. At the same time the little creature appears to have the power of straightening the alimentary canal ; and by its pressure against the bottom of the cell, the extrusion of the body is aided and completed.*

* It would appear as if muscular fibre were here reduced to its simplest con- dition. The filaments are totally disconnected, and are arranged the one above the other in a single series. They pass straight and parallel from their origin to their insertion, and have a uniform diameter throughout their course, except that each filament generally presents a small knot upon its centre, which is most

ZOOPHYTA ASCIDIOIDA. 243

The cell tenanted by this polype is of a tubular, an elliptical, oval, or hexangular figure, circumscribed by distinct walls which apparently separate it from those that lie in juxtaposition, and hinder any intercommunity. The isolation, however, I believe to be more apparent than real. In Vesicularia the cells are apart from each other, and rise from a common tube, — the zoo- phyte affording by this disposition of them a very favourable ob- ject for observing their true connection. Now Ellis states that while a branch of this species was in a watch-glass of sea -water, on the stage of the microscope, he " could plainly distinguish that the internal hollow part of the whole coralline was filled with the substance of the parent polype, which appeared to be of a tender gelatinous nature ; and upon the least extension or contraction of the young polypes, this tender fleshy substance was visibly affected ; for each one was united to it by their lower part or tail."* I think 1 have also noticed a distinct thread of communication between the polypes of the Flustra ; and though tlie closeness of their proximity, and their opacity, may prevent the demonstration in other genera, yet a like union may be probably inferred, for other conclusion seems incompatible with the mode of increase of the polypidoms, and the regula- rity of their patterns.

The polypidom, formed in some species of a congeries of many thousand cells, begins with one only. This original or seminal cell has no sooner been completed, or even in many in- stances previous to its perfection, than another begins to shoot out from a fixed point of its parietes, the bud gradually en- larging and developing itself until the form and size of the pri- mary one has been attained.-f- This process can most easily be

apparent when it is in a state of contraction, at which time the whole filament also is obviously thicker than when relaxed. The filaments have a watery tran- sparency and smooth surface, and under the highest powers of the microscope present neither an appearance of cross markings nor of a linear arrangement of globules." Farre in Phil. Trans, an. 1837, p. 394.

* Essay on Corallines, p. 21.

f Of Lcefling's observations on Meinbranipora pilosa, Pallas says — " Vidit propagari seu augeri, per gemmas a marginalibus seu extremis cellulis protrusas, in perfectas cellulas efBngendas, e quibus polypus dein exseritur. Interdum 2 proles ab eadem cellula, at non simid exseri, sicque series duplicari atque in la- titudinem pandi cnistam vidit." Elench. Zooph. p. 51. See also p .34.

244 ZOOPHYTA ASCIDIOIDA.

traced in the Vesiculariadse, and in our common Flustrae and Escharinae, where round the margin of the crust, cells can at all seasons be observed in every stage of their evolution ; — one just jutting out, another half-formed, and others again nearly com- plete. They never begin their original in the body of the po- lype, but always from the parietes, or rather the connecting medium ; * nor indeed is the embryo distinguishable within until the cells have made considerable advances to maturity. Then the softer parts begin to assume a shape, and gradually to limb themselves after the similitude of their antecedent co- partners, when having reached their term and ready for a par- tial independency, they burst their outward cerements, always at a fixed point, prepared for their exit by the same Power which has moulded the whole.

From this mode of increase there would seem to be no natu- ral limits set to the magnitude and duration of the polypidom, except what arise from accident or extrinsic causes. The ori- ginal polype and its immediate successors may grow old, lan- guish and die ; but the solid cells remain in their connection as a root and fixture, while the newer races, which have sprung up towards the outskirts, continue their work, — generation fol- lowing generation in rapid and ever-multiplying successions. The polypidom in this respect i-esembles a tree in its growth : the trunk and main branches have stood years and centuries, but the increase has been made by annual shoots and renewals, and the last know only vigour and juvenescence. And as the form of the tree depends on the fashion of its ramifications, so that of the polypidom on the mode of evolution of its cells, for every part of the axis is not equally organized to produce buds, nor the same parts in all. Hence if the primitive cell has only one point fitted for this gemmation, the polypidom will be builded up in a catenated chain ; if the cell has two points, two series

* They, in this respect, are formed the same as the Asteroida, of which Milne- Edwards says: — " On voit done qu' ici la partie qui donne naissance aux bour- geons reproducteurs est precisement la partie qui n'api)artient en propre a aucun des Polypes reunis en masse, mais qui leur est commune a tons. Le tissu gene- rateur entoure ces petits etres comme une sorte de gangue vivante et produit dans la profondeur de sa substance de nouveaux polypes sans qu'aucun de ceux deja existans paraissent intervenir d'une maniere directe dans I'acte de la repro- duction. ' Ann. dcs Sc. Nat. iv. p. 310. 1835.

ZOOPHYTA ASCIDIOIDA, 245

of cells are formed, and in several the multiplication goes on in a regular arithmetical progression ; but in others the cells are heaped together without apparent regularity, as in Alcyonella and Alcyonidium, where the softness of all the parts seems to allow of a non-regulated succession of buds. The general dis- position of the cells, however, in this order is certainly after the quincunx, affording examples which the learned Sir Thomas Browne would have gladly adduced in proof that " Nature geo- metrizeth and observeth order in all things, and of the generality of this mystic figure." Nor indeed were they entirely overlooked by this observant physician. " The spongy leaves of some sea- wracks," he says, " Fucus, Oaks, in their several kinds, found about the shear, with ejectments of the Sea, are over-wrought with net-work elegantly containing this order (the quincunx) : which plainly declareth the naturality of this texture ; and how the Needle of Nature delighteth to work, even in low and doubtful vegetations."*

Whilst the composite individual is thus increased by gemmules or buds, the species is propagated and diffused by means of ciliat- ed ova, of which the source has been a matter of some difference of opinion among naturalists. There appear at certain seasons, on many of these zoophytes, round pearly testaceous bodies which are placed on or above the mouths of the cells. Ellis believed these to be their matrices or ovaries " which, in time," he says, " may unfold and extend themselves into those many beautiful tree-like forms that we find them in."f This opinion was also adopted by Pallas, because of the seasonal appearance of the bodies in question, and because they are found only over full-^rown and matured cells.! No one after this seems to have held other belief, § until recent discoveries, demonstrating the complexity of the organization of this order, rendered the exis-

• The Garden of Cyrus, p. 33. Lond. 1686. folio.

f Essay on Corallines, p. xi Ellis's earlier conjectures, which, being erro-

■neous, it is unnecessary to detail, may be seen in Phil. Trans, abridg- (an. 1753) X. p. 346.

I Elench. Zoophytorum, p. 36.

§ " I am inclined to consider them as ovaria enclosing the germs of future individuals ; having observed that these vesicular bodies are sometimes whole, and in this case I have always found them filled with small globular bodies." Lamonroux, Corall. p. 58.

•246 ZOOPHYTA ASCIDIOIDA.

fence of an internal separate ovary probable ; and some have asserted its discovery. Mr Thompson, for example, maintains that the organ suspended from the bend of the body of the Ve- siculariadge is " an ovum or ovarium," because it is " quite ana- logous in situation with the same organ in the lately discovered compound Ascidise ;"* and when treating of the Cellarise Milne- Edwards assigns to this organ a similar function, -f- but in other places he tells us that it is connected with the biliary secretion. I Previously however to the researches of either Thompson or Ed- wards, Professor Grant had told us that the ova were generated exterior to the body of the polype and disjunct from it, pullulat- ing from the common connecting medium, for the ova and gem- mules have the same origin, but the ova sprout from its inner surface, whereas the gemmules grew from the exterior side on- ly, and in consequence are capable of being developed without separation. The correctness of this opinion seems to be prov- ed by the observations of Dr Grant on the Flustra, in which he saw that the ova were developed from the sides of the cell, which they gradually filled by their increase in size, the body of the polype being at the same time absorbed ; by the observations of Raspail on the Alcyonella in which no ovary could be de- tected, and in which the ova are evidently the produce of a part disconnected with the animal viewed abstractedly ; and by the researches of Dr Farre, who has equally proved that there is no ovary in the Vesiculariadse, the organ which had been so considered being in fact the proper stomach.

The following synopsis exhibits the genera arranged under their respective families, but at the same time it ought to be re- membered that as, of many of the species and of some genera, the polype remains unknown, their true position in the class is only conjectural.

• Zool. Researches, p. 96.

f " On remarque aussi au bas de I'anse, forme par I'intestin, un organe par- ticulier qui pourrait bien etre un ovarie destine a produire des gemmes reproduc- teurs." Lam. Anim. s. Vert. ii. p. 175. 2de edit.

^ " — une anse a laquelle est comme suspendu im appendice ceecal gros et court." Ibid. p. 214. This opinion is also that of Professor Grant. Outlines of Comp. Anat. p. 314.

1.

ZOOPHYTA ASCIDIOIDA. 247

* Natives of the sea. (Tentaciila forming a perfect circle.) Polypiaria infundibalatii P. Gervais.

Family I. VESICULAKlADiE.

Poh/pidoms corneous, Jistular, conjervoid : cells vesicular, deciduous, non-oijerculate.

22. Vesicularia. Cells ovate, disjunct, uniserial, unilateral.

23. Serialaria. Cells tubulous, adjacent, uniserial, unilateral.

24. Valkeria. Cells ovate, clustered, or in pairs.

23. Bowerbankia. Cells elliptical, irregularly scattered, unila- teral.

Family II. CRISIADiE.

Pohjpidom calcareous or suhcalcareous, branched, confervoid, jointed : the cells linked together in one or more series, distinct, tubular or elliptical, ivith a terminal or suhterminal aperture, never closed loith an operculum.

26. Crisia. Cells tubular, catenated in one or two alternating series, the aperture round and terminal.

27. NoTAMiA. Cells ovate, geminate, opposite, the aperture suhterminal.

28. HiPPOTHOA. Cells elliptical, linked together, the aperture

superior and lateral.

29. Anguinaria. Cells spathulate, separate, the aperture lateral.

Family III. TUBULIPORIDiE.

Polypidoms calcareous, variable in shape but never confervoid : cells tubular, rowed, rising from a base and projecting, the aperture terminal and non-operculate.

30. TuBULiPORA. Cells tubular, rowed, with distinct parietes.

31. DiscoPORA. Cells tabular, quincuncial, confluent.

Family IV. CELLEPORIDiE.

Polypidoms calcareous or membrano-calcareous, lohed, ra- mous or crustaceans, formed of an aggregation of cells disposed usually in quincunx : cells utricular, in juxta-position, with a contracted terminal aperture, often covered ivith an operculum.

32. Cellepora. Polypidom lobed or raraous ; cells heaped.

33. Lepralia. Polypidom crustaceous ; the cells in a single lay- er, rowed, subaltcrnate, with a contracted orifice.

248 ZOOPHYTA ASCIDIOIDA.

34. Membranipora. Polypidom membranous ; the cells distinct, membranous with an ossified rim to the aperture which is patulous.

Family V. ESCHARIDiE. Polypidoms calcareous^ membrano-calcareous or membranous, very variable in form, composed of cells usually disposed in quincunx ; the cells oblong, pentagonal or hexagonal, conjunct, immersed or horizontal to the plane of axis, icith a subterminal or lateral aperture usually covered with an operculum.

35. Flustra. Cells quadrangular or hexagonal, on one or two planes, forming mat-like expansions, free and foliaceous or incrusting.

36. Cellularia. Cells oblong with a terminal aperture, in two sublaternate rows on a single plane, forming a dichotomously divided narrow subcalcareous polypidom.

37. Acamarchis. Cells oblong with a wide lateral aperture, in two subalternate rows, forming a dichotomous confervoid polypidom.

38. Farcimia. Cells rhomboidal, immersed ; the polypidom di- chotomous, with jointed cylindrical branches.

39. Retepora. Cells immersed, quincuncial, on the upper side of a frondescent, netted, calcareous polypidom.

40. Eschara. Cells immersed, quincuncial, in a double layer placed back to back like the cells in honey-comb, forming a frondes- cent membrano-calcareous polypidom.

Family VI. ALCYONIDUL.^. Polypidoms sponge-like, fleshy, polymorpihous ; the cells irre- gular in disposition, immersed and concealed, loith a contractile non-operculate aperture.

41. Alcyonidium. Cells immersed, irregular, with a contractile aperture, forming a fleshy lobed polypidom.

42. Cliona. Cells amorphous, perforated in a sponge-like polypi- dom strengthened with siliceous spicula.

** Lacustkine. (Tentacula in the form of a horse-shoe.) Polypiaria hippocrepia, P. Gervais-

Family VII. LIMNIADES.

Polypidoms fleshy or spongy or corneous, polymorphous, the polypes placed in tabes tvith angular or round orifices, closed lohen the animals recede.

43. Cristatklla. Polypidom fleshy or sponge-like, massive.

44. Plumatella. Polypidom horny, fistular, confervoid.

FUj. 40.

JV. ZOOPHYTA ASCIDIOIDA.

FAMILY IX. VESICULARIADJS.

Since we profess to be guided, in the classification of zoophytes, by simi- larity in the structure of the polypes considered independently of their poly, pidoms, the Vesiciilariadje, notwithstanding their apparent dissimilarity, must be associated in the same order N\ith Alcyonidium and Flustra. They have been hitherto united with the Sertulariadee, and previous to our knowledge of their polypes, this seemed a very natural union, for the polypidoms of both are slen- der and plant-like, horny, fistular and flexible, and furnished with somewhat si- milar cells on their branches. But the differences between them even in out- ward aspect are not inconsiderable, and although it may be difficult to point out these by any description, they are nevertheless not the less obvious to one fa- miliar with the objects. The polypidoms of the Vesiculariadae are more flexible and of a thinner texture, less arboreal and more confervoid, not so regularly jointed, nor ramified in the same determinate and fixed manner. They are all marine productions, generally not more than an inch or two high, and are found attached only to sea-weeds or other corallines.

For a knowledge of the animated tenants of these structures we are indebted to Cavolini, the Rev. Dr Fleming, J. V. Thompson, Esq. and more particularly to Dr F'arre, of whose researches a summary has been given in the preliminary observations. The following is his description of the cells in the present fa- mily :

" The transparent horny cell which closely embraces the body of the animal is nearly unyielding in its lower two-thirds, but terminates above by a flexible portion, which serves to protect the upper part of the body when the whole is

250 Z. ASCIDIOIDA. Vesicularia.

expanded, in which state it is of the same diameter as the rest of the cell ; but when the animal retracts is folded up and drawn in after it, and completely closes the mouth of the cell.

" The flexible part consists of two portions, the lower half being a simple continuation of the rest of the cell ; the upper consisting of a row of delicate bristle-shaped processes or setae, which are arranged parallel with each other round the top of the cell, and are prevented separating beyond a certain distance by a membrane of excessive tenuity, which surrounds and connects the whole. This mode of termination of the ceU is one of constant occurrence, as will be describ- ed in other species, and is evidently a provision for allowing of the freest possible motion of the upper part of the body in its expanded state, to which it affords at the same time support and protection." Phil. Trans, an. 1837, p. 393.

22. Vesicularia, * Thompson. Charactek. Polypidoms rooted^ confervoid, Jistular.^ horny, dichotomoiisly branched, jointed at the divisions : cells ovate, dis- junct, iiniserial and unilater'al. Polypes ascidian.

1. V. spiNOSA. Dillenius.

Plate xxix. Fig. 1-4. Conferva marina cancellata. Rait, Syn. i. 59, no. 1 1 . Dill. Hist. Muse. '24, no. 22, pi. 4, fig. 22, — fide D. Turner in Lin. Trans, vii. 106 Con- ferva cancellata, Lin. Syst. ii. 720. With. Bot. Arrang. iv. 131

Silk Coralline, Ellis, Corall. 20, no. 17, pi. 11, fig. b, B, c, D Ser-

tularia spinosa, Lin. Syst. 1312. JEllis and Soland. Zooph. 48. Turt. Gmel. iv. 682. Jameson, in Wern. Mem. i. 364. Bosc, Vers, iii. 118. Stew. Elem. ii. 446. Berk. Syn. i. 219. Turt. Brit. Faun. 215. La- marck, Anim. s. Vert. ii. 120. 2de edit. ii. 148. Hogg, Stock. 33

Sert. sericea. Pall. Elench. 114 Laomedea spinosa, Corall. 91.

Templeton in Mag. Nat. Hist. ix. 466 Valkeria spinosa, Flem. Br.

Anim. 551 Vesicularia spinosa, Thomp. Zool. 111. 98, pi. 3. fig. 1-8.

Farre in Phil. Trans, an. 1837, 401, pi. 22 La Laomedee epineuse,

Blainv. Actinolog. 474.

Hab. In deep water, not uncommon. " Junio et Julio mensibus pone Sheerness in insula Shepey copiose observavi," Dillenius. " At the Nore, near the entrance of the Thames," Ellis. Leith shore, Jameson. " Rarely found near Hartlepool," J. Hogg. " Found on the shore of Belfast Lough : common/' Templeton. Liverpool, Hev. D. Landsborough.

Polypidom affixed by a fibrous base, very slender, confervoid, of <i thin membi'anous pellucid texture, much branched, erect, sometimes as much as 8 inches in height, usually about 4 ; main branches com- posed of intertwined capillary tubes, tapered, zigzag ; branchlets arising from the bends, eitlier solitary or in pairs, short, much divided dicho- toniously, the apices pointed and closed ; all the branches are joint-

* From vesicula, diminutive of vesica, a bladder

SEniALAiuA. Z. ASCIDIOIDA. 251

ed under each bend, and the branchlets at each division, and they are perforated with u single series of rather distant holes with a raised rim as if thoy had been bored from within outwards : cells three between each joint, deciduous, oval, transparent. — " The animals are very easi- ly seen in all their details in this species, from the great transparency of the vesicles, and are provided with eight tentacula," Thompson) which '' are ciliated but not armed with spines." Farre.

The holes in the sides of the capillary branches mark the places whence the polype-cells have fallen. The spine-like points in which the divisions of the branchlets terminate have suggested the Linnean specific name ; and that of Ellis and Pallas expresses the silky ap- pearance which dried specimens exhibit. Ellis has well marked the distinctions which separate the species from the Sertulariadse. " The motion of the intestines of the young Polypes was very distinguish- able till the water became putrid ; and then both vesicles and poly- pes dropped off, like blighted blossoms off a tree ; and the substance of the parent polype, though seeming to fill the whole cavity of the branch before, as soon as the water became improper for its support, shrivelled up immediately so as scarce to be visible"

23. Serialaria,* Lamarck. Character. Polypidom confervoid, horny, the shoots slen- der, filiform, Jistular and branched : cells tub ulous, uniserial and unilateral, disposed in close parallel companies at stated intervals. — Polypes ascidian.

1. S. LENDiGERA, much branched, the branches spreading, sub-

dichotomous ; cells in isolated groups, erect, with wide uneven

apertures. — Doody.

Vignette, No. 40, page. 249. Fucoides lendigenim capillamentis Cuscutae instar implexis, Rail, Syn.

38. no. 3 Nit Coralline, Ellis, Corall. 27, no. 24, pi. 15, fig. b. B.

Sertularia lendigera, Lin- Syst. 1311. Pall. Elench. 124. Ellis

and Soland. Zooph. 52. Turt. Gmel. iv. 682. Berk. Syn. i. 218. Stew. Elera. ii- 445. Wern. Mem. i. 5G4. Turf. Brit. Faun. 215. Bosc, Vers, iii. 117. Hogg's Stock. 33. Lister in Phil. Trans, an.

1834, 384 La Sertolara lendinosa, Cavol. Polip. Mar. 229, tav. 9,

fig. 1, 2 Serialaria lendigera, Z,am. Anim. s. Vert. ii. 130. 2de

edit. ii. 169. Risso, L'Europ. Merid. v. 315. Flem. Brit Anim. 547

Stark, Elem. ii. 439. Templeton in Mag. Nat. Hist. ix. 467. Ama-

thia lendigera, Lamour. Cor. Flex. 159. Corall. 68 La Serialairc

lendigere, Blainv- Actinol. 476, pi. 83, fig. 2.

" From seriala, diminutive formed from series, a row.

252 Z. ASCIDIOIDA. Valkeria.

Hah. At the roots of Fuci about low- water mark. " In Sussex - iae littore supra Fucos siliquosum et lumbricalem frequentem banc speciem observavi," Pallas. Leith shore, Jameson. " Found in Belfast Lough, and Dublin Bay, &c." Templeton.

" This extremely small climbing- coralline arises from very minute tubes, by which it adheres to Fucus's, and other marine bodies ; and is so disposed from its jointed shape, that it climbs up and runs over other corallines and Fucus's, as Dodder does over other plants.'' Ellis. The tufts thus formed resemble a flock of hair with clusters of nits scattered over it, and though the comparison is an ugly one, it is yet expressive. The filaments are capillary, smooth, pellucid, kneed and jointed at their dichotomies, immediately imder which the cells are usually placed in a short row containing from four to eight or nine cells, growing gradually shorter outwards, and so arranged as to resemble a Pan's-pipe in miniature " with cylindrical reeds vary- ing in their length." — That the Polypes are ascidian is satisfactorily proved by Cavolini ; and Lister informs us that they have eight ciliat- ed arms.

24. Valkeria, * Fleming. Character. Polyjndom confervoid, horny, Jistular, irregu- larly branched ; the cells ovate, clustered or scattered. — Polypes ascidian, without a gizzard.^

V. CuscuTA, branches opposite ; " cells usually in pairs, op- posite." Ellis.

Climbing Dodder-like Coralline, Ellis, Corall. 28, no. 26, pi. 14, fig. c. C Sertularia Cuscuta, Lm. Syst. 1311. Pall. Eleneh. 125. Ellis and

* " This genus is dedicated to the late Dr John Walker, Professor of Natural History in the University of Edinburgh, a laborious and an accomplished natu- ralist." Fleming. Sir J. E. Smith characterises him as " a most amiable, wor- thy and ingenious man." Sir James visited Moffat in the autumn of 1782, of which parish Dr W. was the minister. " 1 spent that day," he says, " and the next very happily with the Doctor ; he is a very agreeable man : the life and soul of Moffat ; his loss will be equally felt by the gay, the industrious, and the unhappy," — alluding to his approaching removal or translation to Collington, near Edinburgh. His posthumous " Essays on Natural History," Edin. 1812, Bvo. is an interesting volume, which I have had occasion to regret was not more noticed in our Faunas and Floras.

■f The animal of Valkeria differs from that of Vesicularia and Bowerbankia,

" in the entire absence of the manducatory organ ; a difference which it is of

great importance to observe with reference to a natural arrangement of the

class " Farre-

3

Valkeria.

Z. ASCIDIOIDA. 253

Soland. Zooph. 53. Berk. Syn. i- 218. Turl. Gmel. iv. 680. Turt. Brit. Faun. 214. Wern. Mem. i. 564. J5osc, Vers, iii. 113. Stew. Elem. ii- 444. Fleming in Wern. Mem. iv. 485, pi. 15, fig. 1 Val- keria cuscuta, Flem. Brit. Anim. 550. Farre in Phil. Trans, an. 1837,

402, pi. 23. Vesicularia Cuscuta, Thomp. Zool. HI. 97, pi. 2, fig. 1-

4 La Cuscutaire cuscute, Blainv. Actinol. 497, pi. 82, fig. 2.

Hah. On Fuci and corallines. West coast of England, Ellis. In the Frith of Tay, Rev. Dr Fleming. Leith shore, Jameson.

" The main stems originate from tubular creeping roots, which in- vest marine jijants in shoal water : these stems are often jointed at un- equal distances, and give off a number of short branches, which ori- ginate in pairs from its opposite sides, frequently just above a visible joint ; these branches support the vesicles, which are scattered over their surface in an irregular manner, and do not differ except in size and number of tentacula, from those of V. imbricata : the tentacula being 8 in number." Thompson — " Height seldom above two inches; several stems usually arise from the same base, fiUform, jointed, waved, and support the branches and cells bifariously ; bran- ches opposite, nearly perpendicular to the stem, with a joint imme- diately above their insertion : cells oval, sessile, upwards of ten times the breadth of the stem, in pairs, at remote distances, projecting, and are probably ultimately converted into branches : sometimes they oc- cur in pairs or crowds in the axillae of the branches ; polypi extend considerably beyond the margin, tentacula with hairs, which, by their motions, cause the water to ascend in a current on one side, and de- scend on the other, acting, probably, as aerating organs." Fleming.

2. V. UvA, ^^ stem creeping y irregularly branched ; cells scat- tered." Ellis.

Grape CoraUine, Ellis, Corall. 27, no. 25, pi. xv. fig. c. C, D. Sertularia uva, Lin. Syst. 131 1. Ellis and Soland. Zoopb. 5.3. Berk. Syn. i. 218- Turt. Gmel. iv. 682- Turt. Br. Faun- 215. Stew. Elem. 445. Ja- meson in Wern. Mem. i. 564. Bosc, Vers, iii. 117. Hogg's Stock. 34. Clytia uva, Corall. 89. Templeton in ' i- Nat. Hist. ix. 466 Val- keria uva, Flem. Brit. Anim. 551 La Campanulaire ovifere, Blainv.

Actinol. 473. Hab. " Growing on Fucus's and other corallines, on the British coast," Ellis. Leith shore, Jameson. " Found on Fucus nodosus, on the coast at Kirkubbin, county Down, July 1806," Templeton.

" This exceeding- small coralline creeps on the broad-leafed horn- wrack" (Flustra foliacea ;) "and sends out clusters of vesicles from se- veral parts of its creeping- tube, each of which has a black spot in it, like the spawn of frogs : Or rather, these look when they are mag- nified, like a bunch of full ripe transparent oval-shaped grapes witli

254 Z. ASCIDIOIDA. Valkeria.

the stones in them" — " Among many other marine substances re- ceived fresh from the sea, in September 1 753, this object happened to present itself under ray magnifying- glasses ; when, to my surprise, I found those grape -like bodies were a cluster of polypes, each hav- ing eight claws or tentacula, very lively, extending themselves about in pursuit of prey ; and upon their dying, the animals contracted themselves into their vesicles, which closed at the top : What we discover as a spot, is only the intestines of the polype with its food in it." Ellis.

3. V. IMBRICATA, cells in dense clusters irregularly scattered on the jiolypidom. Adams.

Plate xxix. Fig. 5, G. Sertularia imbricata, Adams in Lin. Trans, v. xi. pi. 2. fig. 3 — 11. Turt.

Gmel. iv. 683. Turt. Br. Faun. 216. Steio. Elem. ii. 450. Thomp.

Zool. 111. 94. pi. I. fig. 1-4 Valkeria glomerata, Coldstream in Edin.

New Pbil. Journ. ix. 235. pi. 2. fig- 1,2: and in Edin. Journ. Nat. and

Geog. So. iii. 53 Serialaria imbricata et S. verticillata, Templeton,

in Mag. Nat. Hist. ix. 467, fig- 66. Hab. Parasitical on various littoral Fuci. On Fucus nodosus in Milford haven, Adams. In small pools, at low-water, near Leith, Dr Coldstream. " On the Fuci and Confervas, on the shore of Belfast Lough, near White-House Point," Templeton. In the harbour of Cove, one of the most obvious and common species, J. Thompson, " Stem simple, slightly branched, partly creeping, pai-tly erect : cells ovate, lengthened, with the mouths slightly compressed quadrangu- larly, scattered over the stem in irregular groups. Before the polype is evolved, the cell is closed at the distal extremity by a conical covering. Polypi with ten tentacula, finely ciliated : they extend considerably beyond the mouths of the cells, to the margins of which each is at- tached by a membrane, which is protruded before the tentacula when the polype is about to expand itself. When alarmed, it contracts very rapidly." Dr Coldstream. — According to Mr Thompson this species creeps over the surface of the Fuci by means of its tubular ramifying roots, and throws off numerous flaccid irregularly branched shoots to the length of from one inch to one and a half or more, often so densely clustered as entirely to cover the plant on which it grows.

4. V. PUSTULOSA, vesicles clustered, unilateral. Ellis.

Plate xxix. Fig. 7-9. Dichotomous tubular Coralline, Ellis, Corall. 54. pi. xxvii. fig. h. B — Sertularia pustulosa, Ellis and Soland. Zooph. 54. Turt. Gmel. iv. 680. Bosc, Vers, iii. 113- Steic. Elem. ii. 444. Turt. Brit. Faun.

liowERBANKiA. Z. ASCIDIOIDA. 255

*214. Flem. Brit. Anim. 551 — Vesiculaiia piistuloHa, Thump. Zool. 111. 99, pi. 1, fig. 5—11.

Hab. Parasitical on Fuci. Isle of Wight, Ellis. Cove Harbour, J. V. Thompson.

This " arises from the surface of marine fuci with a straight flex- uose stem, to the height of two or three inches, giving off at each flexure a spreading branch, which in like manner gives off secondary ones, all however, both primary and secondary, lying in the same plane, they are hence what botanists term distich ; each flexure of the stem and branches and each terminal branchlet is composed of a distinct joint, each of which are perforated by a double row of holes from 6 to 18 with elevated margins, on all of which in perfect speci- mens are placed oval transparent vesicles, furnished with animals hav- ing 8 tentacula : the rows of perforations having a spiral tendency, the clusters of vesicles hence present themselves in every direction." Thomjjson.

25. BovvERBANKiA,* Farre. Character. Polypidom confervoid, horny, creeping; the cells sessile, unilateral, irregular, the inflected portion with a spi- nous or filamentous rim : — Polypes ascidian.

1. B. DENSA, matted ; stem creeping ; cells from the sides and upper surjace, thiclily set, elliptical : Polypes ivith 10 tentacula about one-third the length of the body, sparingly hispid along the

outer side. Farre.

Bowerbankia densa, Farre in Phil. Trans, an. 1837, 391, pi. 20 and 21. Hab. " Found commonly on Flustra foliacea thickly aggregated in masses of half of an inch to one inch diameter." Isle of Sheppey, Parre.

" The animal when fully expanded is about one-twelfth of an inch in length. In its retracted state it is completely inclosed in a de- licate horny cell, sufficiently transparent to admit of the whole struc- ture of the contained animal being seen through its parietes. The cells are connected together by a cylindrical creeping stem, upon which they are thickly set, and sessile, ascending from its sides and upper surface."

* " Believing it to be new I have named it after my friend Mr Bowerbank, whose zeal displayed on this as on many other occasions where the study of na- tural history may be promoted, was mainly instrumental in inducing me to fol- low up these investigations, on account of the many supplies that I received from him, and I gladly therefore take the opportunity of acknowledging and record- ing tlie obligation that I am under to him." Dr Farre.

256

Z. ASCIDIOIDA.

BOWEIIBANKIA.

" The animal when completely expanded is seen to possess ten arms of about one-third the length of the whole body, each arm being- thickly ciliated on either side, and armed at the back by about a doz- en fine hair-like processes, which project at nearly right angles from the tentacula, remaining motionless, while the cilia ai*e in constant and active vibration."

2. B. REPENS, stem creeping ; cells irregularly disposed or scat- tered, elliptical. Polypes icitli 12 tentacula. Farre. Vignette, No. 38, page 233. Lagenella repens, Farre in Phil. Trans, an. 1837, 403, pi. 24. Hab. " Parasitic, with a creeping stem, on Sertularia and on Halodactylus diaphanus. Not very common," Farre.

" This species has twelve ciliated arms, not spiny. The alimen- tary canal is short and stout, and whilst the animal is expanded re- mains high up in the body. During retraction the stomach is never brought down to the bottom of the cell, but remains suspended from the upper part of it by the intestine, which appears to have some at- tachment at this point. The upper part of the tube, however, is generally brought down lower than the stomach, in order that the

BowEKBANKU. Z. ASCIDIOIDA. 257

tentacles may be completely drawn in. By this suspension of the stomach from the upj)er })art of the cell a fixed joint is obtained, from which the retracted Hexed portion of the tube may erect itself with the same effect as if the stomach were in contact with the bottom of the cell. This is a point which it would be important to observe in generic distinctions ; but here, as with many other points in this spe- cies, my observations were not carried to the extent that they have been in others, as this was one of the specimens with which my in- vestigations were commenced, and I have never since had an oppor- tunity of confirming them."

" The cells have an oblong form, and are connected to their narrow creeping stem by a short peduncle. The opercular portion terminates in a notched margin, and is very short. (It is possible that this notched margin luay be formed by the extremities of short and broad setae, but this was not determined.) The cells spring from the sides and upper surface of the stem, and turn upwards as in Bow- erbankia. They are set at some distance apart." Farre.

Dr Farre considers this species as forming a distinct genus, but I have not been able to seize upon characters, in his description, of va- lue suflBciently high to justify its separation.

In the Philosophical Transactions for 1834, p. 385, pi. 12, fig. 5, Mr Lister has figured a zoophyte which he refers to the genus Tibi- ANA of Lamouroux, but erroneously in the opinion of Milne-Ed- wards.* It seemingly belongs rather to this than to any other fa- mily of its order, but the polypes, instead of being contained in dis- tinct deciduous cells, issue from one continuous with the common stalk. This is represented as slender, alternately branched, the bran- ches simple, erect, forming a long tubular cell. The polypes appear to have eight tentacula. It was found at Brighton. (See wood-cut No. 42, a, h.)

" A. zoophyte allied to the above was found upon the same marine plants, which seems to be that imperfectly represented by Ellis, pi. xxxviii. 5. F."f

' Ann. des Sc. Nat. Part. Zool. vi. second, ser. p. 18. He refers it to his genus Lucia, slightly indicated in the 2de edit, of Lam. Anim. s. Vert. ii. 72, and says it should stand near to Crisia. Ibid. p. 185. I am not aware that any more detailed account of thj genus or of its species has been published.

f The Hydra coronata of Fleming, Biit. Anim. 554. Ellis's specimens were

parasitical on Plumularia falcata Professor Sharpey has given a figure and

R

258

Z. ASCIDIOJUA.

Fig. 42.

" It consists of a creeping tube and a number of stems branching- from it, each ending in an animal that is shown (not very distinct- ly) at fig. 42, d. The stems, though commonly still, have free power of motion ; and when one is disturbed it bends quickly to and fro, so as to strike one or two more ; these again strike upon others, and thus for a few seconds all are in action : but they soon return to quietness, and the arms, which during the commotion had been doubled in, open again. (Fig. 42, c.)

" The arms are placed on the edge of a pi-etty transparent tunic, and have granulations on their back. They are fringed with cilise possessing the same action as those of Ascidiae and Flustrae ; and in the specimen drawn, small substances were occasionally seen car- ried downwards along them. As in Flustra, a part of the intestine had within it a revolution of particles and dark matter round its axis, and this part communicated with an ascending rectum. The arms at the part of the circle opposite to the rectum appeared to be con-

description of what appears to be the same species in the Cyclop, of Anat. and Physiology, i. 610, fig. 293; for a mere difference in the ramification can scarce- ly be considered specifical in this tribe.

3

Z. ASCIDIOIDA. 259

tinued below the edge of the tunic, and the current produced in the Water, and the food it brought, flowed into a cavity there, at the bot- tom of which was active indistinct motion as if of filaments. A con- nexion was thought to exist between that j)art and the place where the revolution was going- on, but no act of deglutition was per- ceived.

" No current of blood was visible in the stem, nor any circulation either in the body or the arms. Much of the space within the tu- nic was occupied by a darkish appearance, the nature of which was not ascertained. I had not opportunity to inspect other individuals, but the species seemed to be intermediate between such animals of Flus- tra as I had met with, and the pedunculated compound Ascidia; more nearly related to the former, but approaching- the latter in the form of the lower part of the body, the position of the rectum, and the absence of all apparent effort of swallowing : and if with the help of imagination we could connect the ciliated arms together by cross bands at intervals and unite their ends in a circle, extending the tu- nic to meet that circle, and leaving an opening- for the funnel where the rectum is placed, the organ would not be unlike the branchiae of some Ascidise. Indeed the affinity appeared to me not very distant between Ascidia and Flustra ; while, to the Sertulariae, except in the resemblance given by their projecting arms, I can discover no more analogy in the Flustrae than in the Ascidise themselves." Lister.

Fig. 43.

FAMILY X. CRISIAD^.

26. Crista,* Lamouroux. Character. Polypidom conjervoid, Tooted hy tubular fibres, dichotomously branched ; the cells long and tubular^ catenated to- gether in one or two series, the apertures round, terminal, and all inclined to one side. — Polypes ascidian.

* Cells linked in a single series. (Eucratea.;

1. C. cornuta, cells tubulous, curved, the aperture divaricated,

with a long bristle at the bend. Ellis.

Plate xxx. Fig. 1, 2.

Goat's-hom Coralline, Ellis, Corall. 42, no. 10, pi. 21, fig. c, C. Ser-

tularia cornuta, Lin. Syst. 1316. Berk. Syn. i. 220. Turt. Gmel. iv.

686. Turt. Brit. Faun. 217. Stew. Elem. ii. 449 Cellularia fal-

cata, Pall. Blench. 76 C. cornuta, Hogg's Stock. 35 Cellaria

cornuta, Ellis and Solatid. Zooph. 25. Bosc, Vers, iii. 134. Lam. Anim.

* From Kpifftt, separation.

Crisia. Z. ASCIDIOIDA. 261

s. Vert. ii. 139. 2de edit. ii. 187 Eucratea cornuta, Lamour. Cor.

Flex. 149. Corall. 64. Risso, L'Europ. Mend. v. 319. Fkm. Brit.

Anitn. 541. Te.mpleton, in Mag. Nat. Hist. ix. 469 L'Unicellaire

cornue, Blainv. Actinol. 462.

Hub. Parasitical on other corallines, and " adhering to Fuci be- yond low water-mark, not common," Fleming. Very rare at Scar- borough, Mr Bean. Occasionally found in tufts of Crisia eburnea on the coast of Berwickshire, G. J. " Found in the pools on the rocks below Bangor, very common," Templeton.

Polypidom sometimes half an inch in height, very slender, erect, confervoid, white and brittle when dry, rooted by a few tubular fibres, alternately branched, the secondary branches unilateral, secund. The coralline consists of a series of cells placed one above another, the upper cell originating from the one below near the middle, at its point of divarication from the straight line ; and a long tubular spine, which ov^ertops the cell, rises from the same place. The cells are curved, tubular, smooth, the upper half everted, with a plain circular aperture. In some specimens oval-shaped vesicles are found scatter- ed over the polypidom : they originate from the base of a cell, are specked, and have a small tube at the back.

2. C. CHELATA, cells ill the form of a horn; the aperture ob~ lique, marginatedi vAth a spinous process beneath the rim. Ellis. Vignette, Fig. 43, page 260.

BuU's-horn Coralline, Ellis, Corall. 42, no. 9, pi. 22, fig. h,B Sertu-

laria loricata, Lin. Syst. 1316. Berk. Syn. i. 220. Turt. Gmel. iv.

686. Turt. Brit. Faun. 217. Stew. Elem. ii. 449 Cellularia che-

lata. Pall. Elench. 77 CeUaria chelata, Ellis and Soland. Zooph. 25.

Bosc, Vers, iii. 134. Lam. Anim. s. Vert. ii. 140. 2de edit. ii. 189.

Eucratea chelata, Corall. 64, pi. 3, fig. 5 E. loricata, Flem.

Brit. Anim. 541 L'Unicellaire cornet, Blainv. Actinolog. 461, pi.

77, fig. 2 Loricula loricata, Templeton, in Mag. Nat. Hist. ix. 469.

Hah. Parasitical on Fuci, rare. On stones at very low tides, very rare at Scarborough, Mr Bean. " Common on the coast" of Ire- land, Templeton. Cork Harbour, J. V. Thomj^son.

Smaller and more distinctly catenulated than the preceding. Ellis's description is very good. " This beautiful coralline is one of the smallest we meet with. It rises from tubuli, growing upon Fucus's ; and passes from thence into sickle-shaped branches, consisting of single rows of cells, looking, when magnified, like bull's horns invert- ed, each one arising out of the top of the other. The upper branches take their rise from the fore part of the entrance of a cell, where we may observe a stiif short hair, which seems to be the beginning of a

262 Z. ASCIDIOIDA. Crista.

branch. The opening of each cell, which is in the front of its upper part, is surrounded by a thin circular rim; and the substance of the cells appears to consist of a fine transparent shell, or coral-like sub- stance."

* * Cells paired, with a joint between each pair. (Crista.)

3. C. EBURNEA, " cells looselxj aggregated^ cylindrical^ bent, tubidar orifices free^^ Ellis.

Plate xxx. Fig. 3, 4. Tufted Ivory Coralline, Ellis, Corall. 39, no. 6, pi. 21, fig. a, A Cel-

lularia eburnea. Pall. Elench. 73. Hogg's Stock. 35 Sertularia

eburnea, Lin. Syst. 1316. Berk. Syn. i. 220. Turt. Gmel. iv. 686.

Wern. Mem. i. 565. Turt. Brit. Faun. 217. Stew. Elem. ii. 449

La Sertolara d'avorio, Cavol. Pol. Mar. 240, tav. 9, fig. fig. 5, 6

Cellaria eburnea, Ellis and Soland. Zooph. 24. Bosc, Vers, iii. 133.

Lam. Anim. s. Vert. ii. 138, 2de edit. ii. 184. Johnston in Trans. Newc.

Soc. ii. 262, pi. 11, fig. 5 Crisia eburnea, Lamour. Cor. Flex. 138.

Corall. 60. Flem. Brit- Anim. 340. Templeton, in Mag. Nat. Hist.

ix. 468 La Crisie ivoire, Blainv. Actinolog. 460, pi. 78, fig. 3. Risso,

L'Europ. Merid. v. 318. Hah. Parasitical on the roots of sea-weed, and on other zoophytes, very common. " Alibi pollicarem et ultra inveni, in Sussexise v. gr. littore, ubi in Fuco pinastroide, una cum C. falcata et anguina abun- dabat," Pallas.

Grows in little bushy tufts of ivory whiteness, frequently tinted with rose-red, from a quarter to fully an inch in height, attached by a few capillary fibres dilated at their points of insertion into minute calca- reous bulbs. Polypidom much branched, the primary divisions alter- nate, spreading ; the secondary from one side only and bending in- wards with a slight curve. Cells in two rows, nearly opposite or semi-alternate, with a joint between each pair, adnate, frosted, the aperture circular, somewhat oblique, even and entire. Vesicles ob- pyriform, roughish or granulated, sparingly and seldom produced.

4. C. LUXATA, " cells closely aggregated, cylindrical^ nearly straight, with short tubular orifices ; joints black." Rev. J. Fleming.

Plate xxx. Fig. 5, 6.

Crisia luxata, Flem. Brit. Anim. 340 La C. luxee, Blainv. Actinolog.

460. Hah. " On corallines, not rare, from various parts of the coast,'' Fleming. CuUercoats, Northumberland, Mr Jos. Alder. Berwick Bay, very rare.

Polypidom erect, about an inch in height, white and calcareous,

NoTAMiA. Z. ASCIDIOIDA. 268

bushy, dichotomously divided, the branches inclining- inwards ; the joints jet-black ; the internodes narrow at their origin, widened up- wards ; the cells entirely adnate, tubulous, semi-alternate, with round even apertures. This, though in many respects similar to the pre- ceding-, is yet essentially different, and has been well characterized by Dr Fleming-. It is of a denser texture ; the branches, or rather the spaces between the joints, are longer, broader and thicker in the mid- dle ; the cells are more closely connected ; their orifices are not de- tached from the sides, and the joints are black, so that the polypidom appears dotted to the naked eye.

* * * Cells ternate, with a joint above and below. (Tricellaria.) 5. C. ? TERN ATA, " cclls lengthened, rounded at top, with spi- nous processes." Dr David Skene.

Cellaiia ternata, Ellis and Soland. Zooph. 30 — Seitularia ternata, Turt.

Gmel. iv. 687. Stew. Elem. ii. 449. Turt. Br. Faun. 217 Crisia

ternata, Corall. 61 Tricellaria ternata, Flem. Br. Anim. 240. La

Tricellaire ternee, Blainv. Actinolog. 438. Hah. From Aberdeen, Skene. Zetland, Fleming. " Height scarcely an inch, dichotomously branched ; the cells en- large gradually in breadth towards the top, which is armed with two or three spines ; when the outermost one is short, the cell external- ly has an angulated appearance ; at the joints the stem is narrow." Dr Fleming.

27. NoTAMiA,* Fleming. Character. Polypidom plant-like, suhcalcareous, rather soft and flexible ichen dry, much branched dichotomously : cells gemi- nate, exactly opposite, united hack to back with a thick dissepi- ment, a joint above and below each pair.— Polypes ascidian.

1. N. loriculata, cells subcylindrical and obliquely truncated, the aperture plain. Doody.

Plate xxxi. Fig. 12, 13.

Muscus coralloides mollis elatior ramossissimus, Doody in Rail, Syn. 1.

.34, no. 6 Coat of Mail Coralline, Ellis, Corall. 40. no. 7, pi. xxi.fig.

h, B Sertularia loriculata, Lin. Syst. 1314. Turt.Gme\. iv. 684.

Berk. Syn. i. 219. Turt. Br. Faun. 216. Wern. Mem. i. 564. Stew.

Elem. ii. 447 Cellularia loriculata, Pa//. Elench. 64 Hogg's Stock.

33 Cellaria loriculata, Ellis and Soland- Zooph. 24- Bosc, Vers, iii.

133. Lam. Anim. s. Vert. ii. 136. 2deedit. ii. 179. JoAhs^oh in Trans.

• From " r«T8f, dorsum, and tc«ui(oi', cella," Fleming.

264 Z. ASCIDIOIDA. Notamia.

Newc. Soc. ii. 2G2 — Crisia loriculata, Corall. 61. Loricariaeuropsa,

Lamonr. Zooph. 7 Notamia loriculata, P/e??i. Br. Aiiim. 341. Farre

in Phil. Trans, an. 1837, 413, pi. 27, fig. 6-9 Gemicellarialoriculata,

Blainv. Actinol. 461, pi. 78, fig. 4. Hah. " A few fathoms beyond low water-mark," common on all our coast.

Polypidom attached by capillary roots, from 2 to 4 inches long, very bushy, " in cupressi formam elongata," greyish-white, flaccid even when dry ; the branches close, erect, dichotomous, filiform, con- sisting of a series of paired cells divided by a simple joint. Cells adnate, smooth, obliquely truncated, placed back to back, "• so that the pair together resemble a coat of mail, or pair of stays ; and the en- trances of the cells look like the places for the arms to come out at." Ellis. The Polypes have 10 tentacula : they have no gizzard, but in other respects the alimentary canal presents the usual details. Farre.

2. N. ? BURSARiA, cells compressed, keel-shajjed, " ivith a little tube, sivelling at top like a tobacco-pipe, that appears to come out of them:' Ellis.

Shepherd's-purse Coralline, lEMis, Corall. 41, no. 8, pi. 22, fig. a, A

Sertiilaria bursaria, Lin. Syst. 1314. Tnrt. Gmel. iv. 684. Berk. Syn. i. 219. Steiv. Elem.ii. 447. S. Bursa, Turt. Brit. Faun. 216

Cellularia bursaria, Pall. Elench. 65. Ellis in Phil. Trans. Ivii. 437, pi.

19, fig- 12 Cellaria Bursaria, Ellis and Soland. Zooph. 25. Bosc,

Vers, iii. 134. Lam. Anim. s. Vert. ii. 140. 2de edit. ii. 189 Dy-

namena bursaria, Corall. 79. Blainv- Actinol 483 Notamia bursa- ria, Flem. Brit. Anim. 541 Gemicellaria bursaria, Blainv. Actino-

log. 461. Hah. Parasitical on sea-weeds, very rare. " Mare anglicura, in cujus fucis crescit parasitica," Pallas.

" This most beautiful pearl-coloured Coralline adheres by small tubes to fucus's, from whence it changes into flat cells; each single cell like the bracket of a shelf, broad at top, and narrow at bottom ; these are placed back to back in pairs, one above another, on an ex- tremely slender tvdie, that seems to run through the middle of the branches of the whole coralline. The cells are open at top. Some of them have black spots in them : And from the top of many of them, a figure seems to issue out like a short tobacco-pipe ; the small end of which seems to be inserted in the tube that passes through the middle of the whole.

" The cells in pairs are thought by some to have the appearance of the small pods of the Shepherd's Purse : By others, the shape of the seed-vessels of the herb Veronica or Speedwell." Ellis.

HiprOTHOA. Z. ASCIDIOIDA. 265

Milne-Edwards refers this species to Sertularia, section Dyname- na, but there is something in the habit to render this reference very doubtful, unless it is founded on an examination of the polype, which it is not mentioned to be. Lam. Anim. s. Vert. 2de edit. ii. 180.

28. HiPPOTHOA,* Lamouroux. Character. Polypidom confervoid, adherent and creeping^ calcareous, irregularly branched, the branches frequently anasto- mosing, formed of elliptical cells linked to each other at the ex- tremities ; aperture lateral, near the distal end. — Polypes asci- dian.

1. H. CATENULARiA, " cells rounded anteally, tapering to the other extremity, aperture oval." Jameson.

Plate xxx. Fig. 9, 10. Tubipora catenularia? Jameson, in Wern. Mem. i. 561. T. catenulata ?

Stew. Elem. ii. 423 Hippothoa catenularia, Flem. Br. Anim. 334.

H. EUiotae, Gray, Zool. Misc. 34.

ffah. On shells in deep water, not uncommon, Dr Fleming. Ork- ney and Shetland Islands, Jameson. Attached to Pinna ingens in the harbour of Kinglade near Cork, Miss Elliot.

Polypidom closely adherent, much and irregularly branched in a confervoid manner, white, smooth, glossy, calcareous, the branches spreading, frequently anastomosing, sometimes parallel and coales- cing, formed of a series of cells connected like a string of bugles ; cells oval, widest and rounded anteally. the aperture oval with a plain thickish rim, placed near the top. — In its mode of ramification this coralline resembles many of the plant-like figures in marble or agate. " The branches proceed nearly at right angles, issuing from the mar- gin beside the mouth," and will spread, on a favourable site, to such an extent as will cover an inch or two square surface. When alive it " appears like dew drops, and is easily separated from the shell by a pin ; but is strongly attached when dry." Gray. In this state the aperture of the cells is sometimes closed by a membrane, the re- mains of the polype, which remains undescribed.

2. H. LANCEOLATA, cells slender, ovate-lanceolate, the aper- ture small and round. Miss Elliot.

Hippothoa lanccolata, Gray, Zool. Misc. 33.

* A Nereid -.—//esiorf. Tbeog. 251.

The charming Hippothoa and rosy-armed Hipponoe.

266 Z. ASCIDIOIDA. Anguinaria.

Hab. On Pinna ingens in the liarbour of Kinglade, near Cork, Miss Elliot.

" Coral attached, slender, dichotomously and divaricately branch- ed, pearly white ; cells slender, linear, ovate, base filiform, generally emitting- a cell at right angles from the middle of each side ; mouth small, round, with a raised margin, placed near the top of the cell."

" This species is very like H. divaricata, t. 10, f. 15, 16, Lamou- roux, Expos, but he describes and figures the cells as fusiform, and not ovate, lanceolate, and his is fi'om a Fucus." Gray.

29. Anguinaria, * Lamarck. Character. Polypidom calcareous, creeping, adnate, slen- der, Jistular, the cells scattered, erect, free, spathulate, tvith a la- teral aperture near the apex, — Polypes ascidian.

1. A. SPATULATA. J. Ellis.

Plate xxx. Fig 7, 8.

Snake Coralline, Ellis, Corall. 43, no. 11, pi. 2-2, fig. c, C. D Sertu-

laria anguina, Lin. Syst. 1317. Turt. Gmel. iv. 686- Berk. Syn.i. 220.

Turt. Brit. Faun. 217. Stew. Elem. ii, 449 Cellularia angiiina, Pall.

Elench. 78. Ellis in PhU. Trans. Ivii. 437, pi. 19, fig. 10. Hogg\

Stock. 35 Cellaria anguina, Ellis and Soland. Zooph. 26- Bosc,

Vers. iii. 135 Anguinaria spatulata, Lam- Anim s. Vert. ii. 143. 2de

edit. ii. 196. Stark, Elem. ii. 4-39. Templeton in Mag. Nat. Hist. ix.

466 Ang. anguina, Flem. Brit. Anim. 542. Lister in Phil. Trans.

1834, 385, pi. 12, fig. 4 Aetea anguina, Corall. 65, pi. 3, fig, 6. La-

mour. Soland. 151 L'Anguinaire serpent, Blainv. Actinolog. 467, pi.

79, fig. 3.

Hab. Parasitical on the smaller Fuci, rare. Brighton, Mr Mac- gillivray. Scarborough, Mr Bean. " Found on the shore at Carrick- fergus, on the sand," Templeton.

This remarkable coralline creeps along the stalks of the sea- weed it prefers in a wavy line, the capillary tube swelling out at irregular intervals, and sending up numerous clavate processes or cells, which are from one to two lines high, more or less bent at the top, of a pale pink or flesh-colour or white, smooth, glossy, calcareous ; the aperture inferior, subterminal, oval, with plain margins.

Lamouroux suspected that this might prove different from any po- lypous production, and he felt inclined to class it near to or with the Vorticellae, but the conjecture has been shewn to be groundless by Mr Lister's discovery of its polypes, which are truly ascidian, and nearly allied to those of the Flustra.

* From Anguis, a snake.

Fig. 44.

FAMILY XL TUBULIPORID.E.

30. TuBULiPORA,* Lamarck. Character. Polyindom attached hy a partial adhesion of the base, sometimes crustaceous : cells placed on a calcareous basis, arranged in rotes, long and cylindrical, separate, with a round erect aperture. — Polypes ascidian. f

* Base subcircular, cupped. (Discopora, Fleming.) 1. T. v\T\^K, aperture of the cells round and toothless. Pallas. Plate xxxi. Fig. 1-3. Caryophyllus sive Fuiigites minimus tubulosus littons Ariminensis, Plane.

de Conch, min. not. 26, tab. 2, no. 9 Madrepora verrucaria, Lin. Syst.

1272. Pall. Zooph. var. /3. 281. Turt. Gmel. iv. 616. Turt. Brit. Faun- 204. Stew. Elem. ii. 426. Hogys Stock. 38. Millepora ver- rucaria, Ellis a-nA Soland. Zooph. 137 — Tubulipora patina, Lam. Anim. s. Vert. ii. 1C3. 2de edit. ii. 244. Risso, L'Europ. Merid. v, 338. Johnston in Trans. Newc. See. ii. 269, pi. 9, fig. 8 — T. patene, Blainv.

* From tubulus — a tube, and jrafoc — a passage.

t See " Memoire sur les Polypes du genre des Tubulipores, par M. H. Milne- Edwards," in Ann. des. Sc. Nat. Part. Zool. viii. 321.

268 Z. ASCIDIOIDA. Tubulipora.

Actinol. 425. Milne-Edwards in Ann. des. Sc. Nat. Part. Zool. viii. 329, pi. 13, fig. 1 — Discopora verrucaria, Flem. Brit. Anim. 530.

Hah. On shells and corallines from deep water, frequent. " Mi- nuta specimina ad Angliam in Fucis Escharisque observavi," Pallas.

Polypidom like a little saucer, calcareous, white, about half an inch in diameter ; the base thin, subcircular, forming' a shallow cup crowded with cells in the centre, the margin plain, entire, scored with faint lines ; central cells shorter than those towards the cir- cumference and frequently closed, most of them laid obliquely, but some erect, tubulous, with a round even aperture. — In its perfect state this zoophyte has been aptly compared to a compound flosculous flower ; but specimens sometimes occur without any free margin to the base, when the congeries of cells forms a mere wart-like crust. It is to specimens of this kind, which are not unfrequent and va- riable, (some with erect cells forming a minute fluted column,) that I feel inclined to refer the Madrepora verrucaria of Otho Fabricius, (Faun. Groenl. 430, no. 432,) and the Tubulipore verruqueux of Milne-Edwards, so well described and figured in Ann. des. Sc. Nat. Part. Zool. viii. 323, pi. 12, fig. 1 : remarking at the same time, how- ever, that this celebrated naturalist refers it to the following, of which he considers the Obelia tubuliferaofLamouroux to be another variety.

* * Base ramous. (Idmonea, Lamouroux.) 2. T. SERPENS, " creeping, prostrate, in obtuse linear divi- sions, tcit/i tubular pores on the upper surface disposed in trans- verse roivs." Ellis.

Plate xxxi. Fig. 4-6. Small purple Eschara, Ellis, Corall. 74, no. 6, pi. 27, e, E — Tubipora serpens, f-in. Syst. 1271. Fabric. Faun. Grcenl. 428. Turt. Gmel. iv. 614. Jameson in Werri- Mem. i. 561. Stew. Elem. ii. 426. Bosc,

Vers, ii. 351 Millepora liliacea. Pall Elench. 248. Turt. Gmel. iv.

639. Twr^. Brit. Faun. 205. Bosc, Vers, ii. 345 M. tubulosa, iJffis

and Soland. Zooph. 136. Turt. Gmel. iv. 639. Turt. Brit. Faun. 205. Stew. Elem. ii. 428. Bosc, Vers, ii. 345. Hogg's Stock. 37 Tubuli- pora transversa. Lam. Anim. s. Vert. ii. 162. 2de edit. ii. 242. Stark, Elem. ii. 437. Larnour. Zoopb. 1, pi. 64, fig. 1- Risso, L'Europ. Merid.

V. 338. Jo/ui.s^on in Trans. Newe. Soc. ii.269 Tubulipora transversa,

Blainv. Actinolog. 424. T. pourpre, Ibid. Atlas, pi. 72, fig. 3 T.

serpens, Flem. Brit. Anim. 529.

Hab. Attached to corallines, old shells, Sec. especially to Plumu-

laria falcata. Common on all parts of the coast. " Ex mari Cor-

nubiam alluente allatse Sertulariae eandem crebram, in piso majores

glomeres convolutam aut laciniosos passim et revolutos flosculos

TuBULiPoiiA. Z. ASCIDIOIDA. 269

mentientem exhibuerunt," Pallas. Orkney and Shetland islands, Jameson.

Polypidom adherent by a narrow base, calcareous, of a faint pur- ple colour or white, depressed, irregularly divided, the segments flat, bifid, spreading, more or less revolute, obtuse, the under surface even and striate, the upper rough with the tubulous cells arranged in trans- verse rows, but divided by a central groove, which winds along the branches : the cells are generally placed in close apposition, some- times they are disjunct, and the walls are minutely frosted. — The entire polypidom rarely exceeds half an inch in length.

Milne-Edwards is of opinion that the T. serpens of O. Fabricius is not synonymous with the Linnaian species, but with the T. fim- briata of Lamarck, in which opinion a re-perusal of the description, in the Fauna Gro?nlandica, does not induce me to coincide. Milne- Edwards refers our polypidom to the genus Aulopore. Ann. des Sc. Nat. Part. Zool. viii. 331.

3. T. TRUNCATA, " stem round, branched, ending icith enlarg- ed globular heads, radiated with plates of united vertical cells." Jameson.

Tubulipora truncata, Flem. Br. Anim. 329 Millepora truncata? Ja- meson in Wern. Mem. i. 560 T. tronque, Blainv. Actinol. 425.

Hab. " In deep water, Zetland," Dr Fleming. Shetland Islands, Jameson.

" About an inch in height, the branches scarcely exceeding one- eighth ; the branches are short, pierced by numerous pores, the open- ings of cells converging towards the centre ; the head is stellate, the rays are highest in the middle of their course, diminishing towards the centre and lower margin of the head ; each ray is compressed, and consists of two rows of tubular cells, united, crowded, with sub- angular orifices ; the tubes have a central direction, and give to the sides of the plates a striated appearance. This species has probably been referred to as an inhabitant of the north seas, under the title of Millepora truncata,* but it differs widely from the Myriozoos of Donati, to which the term was restricted by Pallas." Fleming.

* * * Crustaceous. (Obeli a, Lamouroux.) 4. T. Obelia, crustaceous, the cells in rows, tubular, icith an oblique even rim. Miss Elliot.

Plate xxxi. Fig. 7, 8.

* Stew. Elem. ii. 426, pi. 12, fig. 7-

270 Z. ASCIDIOIDA. Discopora.

Obelia tubulifera? Blaiiw. Actinolog. 424, pi. 71, fig. 1. Lam. knim. s. Vert. 2de edit. ii. 246 O. tubifera? Gray, Zool. Misc. 35.

Hab. In the harbour of Kinglade near Cork, parasitical on a Pinna, Miss Elliot. In deep water at Scarborough, on Modiola vulgaris, rare, 3Ir Bean.

Crust rather thin, entirely and very closely adherent, chalk- white, even, spreading in somewhat circular expansions : the cells alter- nate, rather distant, rowed, radiating from several centres, divided by paler lines, horizontal, tubulous, mostly immersed, the mouths raised with a wide round oblique plain aperture.

This description is taken from a specimen in the collection of Mr Bean. It adheres to the shell of Modiola vulgaris, and is six-tenths of an inch in one direction and nearly five-tenths in another. The re- semblance between it and Obelia tubulifera is fully sufficient to war- rant the conjecture of their identity, for the differences which the student will detect between our figure and that of Laraouroux, copied by Blainville, are probably the mere peculiarities which mark the in- dividuals of a variable species. Of Obelia as a genus, Blainville re- marks that it is truly unimportant, scarcely differing from Tubuli- pora ; and the merging of them into one seems therefore a natural union, while at the same time we get quit of a name that has been also applied to some Medusae.

Of Obeliae generally Mr Templeton says, " There are at least^fe native uncharacterised species, on small corallines and shells, very com- mon in protected bays" of the Irish coast. Mag. Nat. Hist. ix. 470. To determine these will be the pleasant duty of the naturalists of that country.

31. Discopora,* Lamarck. Character. Polypidom calcareous, adherent throuylwut ; the base a circumscribed crust ; the cells coalescent, indistinctly quincuncial, tubular, erect, with a round patulous terminal aper- ture without an operculum. — Polypes unknown.

1. D. HispiDA, crust spreading subcircularly, roughish, wavy or ridged ; the cells erect, obscurely voiced, with one larger and two minute denticles on the side of the apertures.— T>v Fleming.

Plate xxxi. Fig. 9 — U.

Discopora hispida, Flem. Brit. Aiiim.530 Le discopore h^visse, Bluinv.

Actinolog. 446. Hab. " On Corallines from deep water. Zetland," Fleming.

' From discus, a flat plate or disk, and ■n-opoi.

Pherusa. Z. ASCIDIOIDA. 271

Coast of Devonshire, Dr Coldstream. Stevenston, Ayrshire, Rev. D. Landsborough.

" Breadth nearly an inch, hispid ; the cells seem distributed over the whole surface, and more vertical than the preceding ( Tub. pati- na) ; there are, however, waved porous grooves, and the cells seem disposed on each side of these in irregular transverse rows, united or free, short, with expanding orifices dividing into irregular spinous pro- cesses." Fleming. — I have two specimens of a polypidom, given to nie by Dr Coldstream, which agree very well with this description, and are figured in the plate referred to, but they adhere to a piece of sand- stone, and were found in situ at low-water mark. The crust is half an inch or a little more in diameter, and scarcely a line in thickness, circumscribed by the thin very narrow edge of the basilar layer. It is hard, calcareous, entirely adherent, of a greyish white colour, with lighter slightly elevated roundish spots on the surface, or raised into transverse ridges, conforming in this respect, perhaps, to the form of the rock over which it spreads. The cells are barely visible with the naked eye, erect, very close or coalescent, and not arranged distinct- ly in any order. Their apertures are even with, or raised somewhat above, the surface, circular, and armed on one side with three small teeth, of which the central one is larger than the other. Many of the cells are destitute of these, which are only perceptible when the polypidom is viewed obliquely.

The genus Discopora differs from Tubulipora in having cells in such close and intimate union that they seem almost to be rather immersed or excavated in the crust than separate tubes ; while from Lepralia it estranges itself by the erect position of its cells, their tubular form and non-constricted aperture, which, moreover, are at no season closed with ovaries. The British species answers so well to Lamarck' s definition of Discopora verrucosa, Anim. s. Vert. ii. 165 ; Stark, Elem. ii. 436 ; that at one time I had concluded their identity to be scarcely doubtful, but Blainville's figure (if correct) of the latter proves the contrary, and represents a species with oblique ventricose cells, similar in all apparent respects to those of a Lepralia, The fi- gures I give of the natural size are very exact to nature, — that drawn iinder the microscope is perhaps less characteristic, but there was no possibility of communicating to it a greater verisimilitude.

Pherusa tubulosa, Lamoiir. Corall. 53, pi. 2, fig. 1. Blainv. Actinolog. 453, pi. 80, fig. 1. — Flustra tubulosa, Ellis 'AnA Soland,

272 Z. ASCIDIOIDA. Filipora.

Zooph. 17. — According- to Mr Templelon this is '< found affixed to Sertularise, &c." on the coast of Ireland. Mag. Nat. Hist. ix. 469.

TuBiPORA MusicA, Lin. Syst. 1270. Marked as British by 3Ir Stewart, Elem. ii. 425,— without doubt erroneously.

Filipora filograna, Fleming, Brit. Anim. 530 : Tubipora fas- cicularis, Stew. Elem. ii. 426 ; Jameson in Wern, Mem. i. 561 ; is a species of Serpula, as it was properly described by Linnaeus and Pal- las, Elench. Zooph, 240. The most accurate description of the spe- cies is given by the Rev. M. J. Berkeley in Zool. Journ. iii. 230.

Fig. 45.

FAMILY XII. CELLEPORID^.

32. Cellepora,* Otho Fabricius. Character. Polypidom calcareous, cellular, irregularly loh- ed or ramous, formed of urceolate cells heaped together or arrang- ed in quincunx. — Polypes ascidian.

1. C. vvMicosA, glomerous, rough, porous ; cells sub orbicular, the mouth round toith a produced marginal process. J . Ellis. Plate xxxii. Fig. 1, 2, 3. Porous Eschara, Ellis, Corall. 75, no. 7, pi. 27, fig. /, F, and 72, pi.

30, fig. d, D. Tubipora verrucosa, Lin. Syst. edit. 10, 789

Cellepora pumicosa, Lin. Syst. 1286. Mull. Zool. Dan. prod. 253. Turt. Gmel. iv. 640. Berk. Syn. i. 212. Wern. Mem. i. 560. Turt. Brit. Faun. 206. Stew. Elem. ii. 428, pi. 12, fig. 16, 17, copied from Ellis. Lam. Anim. s. Vert. ii. 170. 2de edit. ii. 256. Corall. 40. Boic, Vers, iii. 147, pi. 3, fig. 3. Flem. Brit. Anim. 532. Hogg's Stock. 37. Stark, Elem. ii. 436. Johnston in Trans. Newe. Soc. ii.

267. Templeton in Mag. Nat Hist. ix. 469 C verrucosa, Lin. Syst

1286. Fabric. Faun. Groenl. 434 C. spinosa, Turt. Brit. Faun. 205.

Millepora pumicosa, Pall- Elench. 254. Ellis and Soland. Zooph.

135. Turt. Gmel. iv. 639. Wern. Mem. i. 560. Stew. Elem. ii. 428.

Flustra buUata? Ellis and Soland- Zooph. 16. Stew. Elem. ii.

436. Turt. Gmel. iv. 664 Le cellepore pouce et C. verruqueux,

Blainv. Actinolog. 443-4. Hab. Found on the stems of various corallines, on stones, and on the roots of Fuci, common.

The cells, by their conglomeration, form a porous friable calcareous

' From cella a cell, and 5r«{of. S

274 Z. ASCIDIOIDA. Cellepora.

mass, encrusting- submarine bodies, rarely exceeding an inch in length, usually round when small, more or less oblong and knobbed when large. It is rough, when quite recent of a pinkish colour, dirty-white when dry, rarely tinted with purple. The aperture of the cells is often toothless, but in a perfect condition a short mucro projects

from the superior margin, and often a lesser one on each side.

Linnaeus' description under C. pumicosa is scarcely applicable, but his quotation of Ellis's figure determines the species he had in view. There can be little doubt that his C. verrucosa — " cellulis suhrotun- do-glomeratis ovatis ore suhtridentato" — belongs to the same species, although Blainville considers it synonymous with the Discopora ver- rucosa of Lamarck.

2. C. RAMULOSA, dichotomously branched, the branches cy- lindrical, rough ; cells irregularly clustered^ loith a mucro on the outer edge of the aperture. Pallas.

Plate xxxii. Fig. 4, 5. Cellepore ramulosa, Lin. Syst. 1283. Mull. Zool. Dan. prod. 253, no. 3049. Bosc, Vers, iii. 148. Flem. Brit. Anim. 532. Johnston in Trans. Newc Soc ii. 267, pi. 12, fig. 3, 4. Lam. Anim. s. Vert. 2de

edit. ii. 258 La C. rameux, Blainv. Actinol. 443.

Hah. In deep water, attached to old shells, " not rare," Fleming. Lizard Point, Cornwall, Pallas. On Serpula tubularia from the coast at Dunstanborough Castle, 3Ir R. Emhleton. Coast of Berwick- shire, occasionally, G. J.

Polypidom attached by a spreading base, calcareous, white, light and porous, rising to the height of between 2 and 3 inches, branch- ed from the base, the branches bifid, spreading, cylindrical, the ulti- mate ones a little attenuated at the apex, very rough with the mu- cronate cells, which are urceolate, without any very regular arrange- ment^ the aperture contracted, the mucro about as long as its diame- ter. Pallas (Elench. 233,) and Ellis (Soland. Zooph. 136,) con»

sidered this a variety of the preceding. The polypes are of a faint

red or flesh coloiir, with two darker spots indicating the position of the stomach and ovary ; tentacula numerous, filiform.

3. C. Skenei, much compressed, divided in a bifid manner, rough ; cells roived, with a strong mucro on the outer edge of the 7'ound aperture. Dr David Skene.*

Plate xxxii. Fig. 6, 7, 8.

* " Dr David Skene — after a short time of study at Paris, in addition to the more ordinary preparations — settled as a medical practitioner in Aberdeen, where

Cellepora. Z. ASCIDIOIDA. 275

Millepora Skenei, Ellis and Soland. Zooph. 135. Turt. Gmel. iv. 635.

Turt. Brit. Faun. 204. Stew. Elem. ii. 427 Cellepora palmata,

Flem. Brit. Aniin. 532. C. Skenei, Johnston in Trans. Newc Soc.

ii. 267 L'Eschare palmee, Blainv. Actinol. 428.

Hab. In deep water, attached to shells and corallines. Near Aber- deen, Skene. " A single specimen from deep water, Zetland," Flem,' ing. Coasts of Northumberland and Berwickshire, not rare.

Polypidom attached by a spreading base, calcareous, erect, from half an inch to an inch high, much compressed, divided in a palmate manner, the segments truncate, the surface very rough with the mu- cronate cells, which are immersed, arranged in regular rows, and have a roundish aperture guarded by a strong divaricate mucro, and in some of the cells there are one or two shorter spines at the base of this. From these spines being worn away the base of the polypidom

his father and grandfather had been physicians of reputation ; and he soon be- came eminent in his owti profession, as well as in literature and science- To Botany he was particularly devoted ; and he frequently herborized in company \vith Principal Campbell and Dr Reid, who were both fully aware of his merits. The former is said to have often lamented that his observations on plants had never been given to the world ; while Dr Reid, in a letter addressed to him, observes, regarding his extensive acquirements — ' But is it all to die with you, and to be buried in your grave ? This, my dear sir, ought not to be. Stultum est peritura parcere chartce. Can you find no time either when you are laid up in the gout, or when the rest of the world is in good health, to bequeath something to posterity? Think seriously of this.' I find the same distinguished philoso- pher in another of his letters from Glasgow, urging the physician to present himself as a candidate for one of the medical chairs of that place, about to be- come vacant by the removal of Dr Black to Edinburgh, particularly as this might become a step towards the University of Edinburgh, to which Dr Reid thought his ambition should extend. Nor was this a mere partiality derived from previous personal intimacy ; for more than one seem to have been anxious that the Scottish metropolis should become Dr D. Skene's place of abode. Thus Lord Kames, a frequent and attached correspondent, says in one of his letters (dated Blair Drummond, 11th January 1769,) ' I have a most hearty re- sentment at you for refusing the off'er made you by Dr Hope, which would have settled you in the town of Edinburgh, much to your profit I am certain ; but no particulars till I see you in the Harvest circuit ;' and in another, ' I wish from my heart to have you settled here, and cannot but regret a good opportunity you missed.'" Dr Skene was also the correspondent of Pennant, Ellis, Walker, and of Linnaeus, several of whose letters to him are still preserved. He died in December 1771, aged 36, leaving behind him numerous manuscripts ; and a museum, consisting of plants, minerals and shells, which might well have been called immense. Taking him all in all he was " probably as extraordinary a man as the north of Scotland ever produced ;' and it is hard to believe that, even in his native city, his name should now be entirely forgotten. See the " North- ern Flora," by Alexander Murray, M. D. pref. p. x.

276 Z. ASCIDIOIDA. Cellepora.

is generally smooth and more or less rounded : it is sometimes of a yellowish-brown colour, but commonly white, and when dry appears " as if covered over with a silver varnish."

Notwithstanding the apparent dissimilarity in habit of the three preceding Celleporae, 1 cannot but suspect that they are merely dif- ferent states of the same species : for in these productions the "fronti nulla fides" receives many an apposite illustration.

4. C. CERVicoRNis, much and irregularly branched ; branches compressed, palmate, truncate ; surface roughish or even, com- pact, with simple circular pores disposed in quincunx. Borlasse.*

Plate xxxiii.

Porus cervinus, Borl. Cornw. 240, tab. 24, fig. 7 Millepora cervicor-

nis. Stew. Elem. ii. 427. Turt. Brit. Faun. 204 M. compressa, Sow-

erby, Brit. Misc. 83, pi. 41. Turt. Brit. Faun. 204. Jameson in Wern. Mem. i. 560 Cellepora cervicornis, Flem. Brit. Anim. 532.

Hab. " In deep water, not rare," Fleming. Cornwall, Borlasse. Devonshire, Dr Coldstream. Shetland Islands, Jameson.

A single specimen of this coral is about 3 inches in height and somewhat more in breadth. It rises from a broad flattened base, and begins immediately to expand and divide into kneed branches or broad segments, many of which anastomose so as to form arches and imper- fect circles. The extreme segments are dilated and variously cut, truncate. Both sides are perforated with numerous pores just visible to the naked eye, and arranged in regular rows : the pores are circu- lar, even with the surface on the smooth and newly formed parts, but on the older they form the apertures of urceolate cells which appear to be formed over the primary layers of cells, and give to the surface a roughish or granular appearance. The orifice is simple, contracted, with a very small denticle on one side. The thickness of the branches varies from a half to two lines ; the interior cellular ; the new parts formed of two layers of horizontal cells, but the older parts are thick- ened by cells superimposed on the primary layers. This species

certainly treads closely upon the genus Eschara, but Dr Fleming and Milne-Edwards, who had examined an authentic specimen in the York Museum, both agree in making it a Cellepora. It is entirely distinct from Eschara cervicornis, with which it has been confounded.

• Borlasse, William, of Ludgvan in Cormvall, T>. D., born Feb. 2, 1695-6 ; elected F. R. S. in 1750 ; died Aug. 31, 1772 : tbe author of a History of Corn- wall still held in estimation ; and characterized by his contemporaries as an " able and worthy man." See I'ennant's Literary Life, p. 1.

Cellepora. Z. ASCIDIOIDA. 277

5. C. LiEvis, " dichotomously branched^ cylindrical, the pores wide, with simple mouths." Rev. Dr Fleming.

Cellepora he vis, jF/em. Brit. Anim. 532. L' Eschars lisse, Blainv. Acti-

iiol. 4-28.

Hah. " A single specimen from deep water, Zetland," Fleming.

" Height an inch and a quarter, diameter one-tenth ; the branches are smooth, with the orifices of the cells smooth and concave ; to- wards the extremities the branches are rough with the forming cells, and the orifices are more declining', circumscribed, a little prominent, with a blunt process at the proximal margin." Fleming.

33. Lepralia,* Johnston. Character. Polypidom calcareous or memhrano -calcareous, adnate, crustaceous, spreading circularly^ formed of a layer ofur- ceolate cells in juxtaposition, horizontal, and arranged in quin- cunx ; aperture terminal, often covered with an opercular ovary. — Polypes ascidian.

* Margin of the aperture plain.

1. B. HYALiNA, " diaphanous, the cells forming an even smooth crust, with tubular simple moutlis." Rev. Dr Fleming.

Cellepora hyalina, Lin. Syst. 1286. Fabric. Faun. Groenl. 4-35. Bosc,

Vers, iii. 148 Berenicea hyalina, Flem. Brit. Anim. 533 La

Berenice hyaline, Blainv. Actinol. 445..

Hub. " On stones, shells, and corallines from deep water," Fleming.

" The crust is semitransparent, the divisions of the narrow cells

indicated by whitish lines, and the orifices are narrow, cylindrical,

simple tubes. The crust is not circumscribed, otherwise it resembles

the genus Discopora." Dr Fleming.

2. L. NiTiDA, cells ovate, prominent, transversely ridged, or, when dry, fissured. Dr Fleming.

Plate xxxiv. Fig. 7.

* Lepralia — " sea-scurf" — derived from Atw^a, leprosy, and otA/oc, marine : an expressive name for the genus suggested by my friend, the Rev. Thomas Riddell. It is spionymous with the " Berenicea" of Dr Fleming, but not of La- mouroux, and the name belongs of right to the latter ; — the more readily yield- ed up since we find a " Berenicea" also amongst the Medusae. Milne- Edwards names the genus " Escharoides," but neither this nor Escharina, another of his names, can be adopted, since some natinalists use the terminations aide and ina as family appellatives. Moreover what saith Linnajus? — " Generic names includ- ing other generic names are unworthy of a scientific nomenclature." And again — " Generic names ending in oides are prohibited." See Young's Med. Litera- ture, p. 28.

278 Z. ASCIDIOIDA. Lepralia.

CeUepora nitida, Fabr. Faun. Grcenl. 435. Bosc, Vers, iii. 148. Lam.

Anim. s. Vert. '2de edit. ii. 259. Corall. 38. Berenicea nitida, Flem.

Brit. Anim. 533- " La B. brillante, Blainv. Actinol. 445.

Hab. On shells, rare, Dr Fleming. In Berwick Bay on Patella caerulea, G. J.

Crust spreading circularly, closely adherent, rather thin, greyish- white, calcareous ; cells contiguous, in radiating rows, large, subalter- nate, ovate, ventricose, silvery, the walls fissured with 6 or 7 cross slits which meet on the mesial line ; aperture subquadrangular, de- pressed, terminal ; anterior to it there is often found a globular smooth pearly oviferous operculum with a round even aperture. The re- markable structure of the cells renders this one of the most interesting species under the microscope. There is sometimes an appearance of a spine on each side of the lower angle of the mouth, which is mere- ly the commencement of the walls of the next cell.

3. L. COCCI NE A, cells ovate, granulous, the aperture with a .•ihort tooth-like process above the superior margin. G. J. Plate xxxiv. Fig. 1, 2, 3.

CeUepora coccinea, Corall. 40 Berenicea coccinea, Lam. Anim. s.

Vert. 2de edit. ii. 259. Johnston in Trans. Newc. See. ii. 267, pi. 12, fig. 3.

Hah. On rocks near low water-mark, and on the roots of Lami- naria digitata, common on the coast.

The spots formed by this species are often an inch or upwards in • diameter, the crust closely adherent, thin, roughish to the naked eye, generally of a flesh-red or purplish colour, but sometimes pure white. The cells are disposed in adjacent rows, either opposite or subalter- nate, and lie upon the crust ; they are ovate, granulated or frosted, and, when dry, sometimes appear to be perforated with minute holes. Above the aperture, and a little removed from the margin, there rises up a blunt white tooth or mucro, but the margin itself is not tooth- ed : the aperture is roundish, emarginated above, terminal, and on each side of many of them, in some specimens, there is a small trian- gular slit, which seems to be the aperture of an abortive or partially developed cell. Many of the cells are usually covered with a large pearly- white striated operculum.

4. L. VARIOLOSA, crust punctured or sometimes frosted only ; the cells immersed, cylindraceous, raised anteriorly, iviih a plain

semioval aperture. G. J.

Plate xxxiv. Fig. 4. Hab. On shells and stones in deep water. Scarborough, Mr Bean. Berwick Buv.

Lepralia. Z. ASCIDIOIDA. 279

Crust spreading, rather thick, adherent, even, often roughened in the centre, greyish -white, dull, the space between the cells closely punctured like the end of a thimble ; cells immersed, cylindraceous or somewhat ventricose, arranged in regular rows divided by a raised line very obvious in recent specimens, the apertures roundish or se- mioval, plain or with a small tooth on the upper edge, and in some cells two short blunt teeth are visible on the upper lip. Opercu- la pearly, globular, smooth. When dry the crust can in some in- stances be separated from its foreign base in small pieces, but in ge- neral it is very firmly adherent, and has a decided tendency to grow in a circular form. In a very fine specimen which Mr Bean submit- ted to my examination, the space between the cells was not punctur- ed, but merelv rough or frosted, which I attribute rather to accident, or to a difference produced in drying, than to any specific character in the zoophyte.

* * Margin of the aperture spinous. 4. L. CI LI ATA, cells ovato-glohose, frosted, the aperture con- tracted, circular, armed with from 5 to 1 long spines. Pallas.

Plate xxxiv. Fig. 6.

Eschara ciliata, Pall. Elench. 38 Cellepora ciliata, Lin. Syst. 1286.

Fabric. Faun. Groenl. 434. Bosc, Vers, iii. 147. Corall. 41

Berenicea utriculata, Flem. Br. Anim. 533. Johnston in Trans. Newc. Soc. ii. 268, pi 12, fig. 6, (not good.)

Hah. On shells and stones from deep water, common.

The crust is always white, spreading circularly, thin and closely adherent, so that it cannot be removed entire from its foreign base. " The cells appear as unconnected though adjacent," and their aper- tures look upwards. The aperture is encircled, for about two-thirds of its circumference, with from 3 to 7 spines almost as long as the cell itself, but they are of unequal lengths, and are so easily broken off that it is rare to find them perfect (very often no vestige of them is visible) excepting near the margin of the crust, or when this lies protected by some inequality of the surface which it grows upon.

I have seen many specimens of this species in the form of a calca- reous compressed mass hispid on both sides with the teeth of the cells, which were aggregated in a double layer. These masses re- semble some specimens of Cellepora pumicosa, or rather of Mem- branipora pilosa, and are proof that the distinctions between the ge- nera are but of secondary importance, as Blainville has properly re- marked.

280 Z. ASCIDIOIDA. Membranipora.

5. L. TRispiNOSA, cells radiating from a centre^ the aperture armed below with 3 lonp spines. G. J.

Platk xxxiv. Fig. 5.

Discopora trispinosa, Johnston, in Edin. Phil. Journ. xiii. 222 Bere-

nicea trispinosa, Johnston, in Trans. Newc. Soc. ii. 268.

Hob. On shells from deep water, rare. Berwick Bay.

Crust thin, circular, adherent, yellowish, or of a silvery white co- lour with minute yellow dots : cells in rows radiating from the cen- tre, horizontal, immersed, the apertures raised, round, cleft, but not deeply, above, and belov/' armed with three spines of which the mid- dle one is the longest. — The margin of the crust is a thin pellicle marked with the raised lines which are to form the partitions between the future cells.

6. L. IMMERSA, crust Spreading irregularly^ the cells immersed with small round apertures^ having a tooth on the proximal and several spines on the distal margin. Fleming.

Plate xxxiv. Fig. 8.

Bereniceaimmersa, F/em. Brit. Anim. 533 B. flava, Johnston, in Trans.

Newc. Soc. ii. 268 La B. immergee, JBlainv. Actinolog. 445.

Hab. On stones and shells from deep water, frequent.

Crust rather thick, spreading irregularly, ochre-yellow, or some- times cream-yellow, roughish and punctured to the naked eye by the apertures of the cells which do not radiate from a centre, though ar- ranged in regular series. They are immersed in the crust so that their divisions are indistinct ; the apertures contracted with a tooth on the upper edge and several spines on the lower margin which are very brittle and liable to be broken off, but when entire are longer than the diameter of the cell.

34. Membranipora,* Blainville. Character. Polypidom encrusting, membrano-calcareous, spreading irregularly, formed of a single layer of alternating ap- proximated cells; cells oval, horizontal, membranous, the aper- ture ■patulous with a hard calcareous rim. — Polypes as'cidian.

1. M. PI LOS A, aperture of the cells with one long hair and se- veral spinous denticles. J. Ellis.

Plate xxxiv. Fig. 10-12. Irregular spongy foliaceous Coralline, Ellis, Corall. 73, no. 4, pi. 31.

* From membrana — a thin skin or film, and Trepm.

Membranipora. Z. ASCIDIOIDA. 281

Eschara pilosu, Pall. Eleiich. 50 Flustra pilosa, Lin. Syst. 1301.

Mull. Zool. Dan. prod. 253. Ellis and Soland. Zooph. 1 3. Berk. Syn. i. 214. Turt. Gmel. iv. 663. Wern. Mem. i. 563. Turt. Brit. Faun. 209. Stew. Elcm. ii. 43G. Base, Vers, iii. 140. Lam. Anim. s. Vert, ii. 159. 2de edit. ii. 224. Grant in Edin. New Phil. Journ, iii. 111. Flem. Brit. Anim. 537. Hogg's Stock. ,36. Bisso, L'Europ. Merid. V. 335. Johnston in Trans. Newc. See. ii. 265, pi. 9, fig. 5. Lister in Phil. Trans, an. 1834, 384, pi. 12, fig. 2. Templeton in Mag. Nat. Hist. ix.

469 La F. pileuse, Blainv. Actinol. 450.

Var. /?. The long bristle abortive or destroyed. Ellis, Corall. pi. 29, fig.

Z). Ellis in Phil. Trans, abridg. x. 492, pi., 12. fig. 4, D Flustra

dentata, Ellis and Soland. Zooph. 15. Turt. Gmel. iv. 664. Turt. Biit. Faun. 209- Stew. Elem. ii. 436. Lam. Anim. s. Vert. ii. 158. 2de edit. ii. 224. Bosc, Vers, iii. 142. Stark, Elem. ii. 437. Hogg's

Stock. 36. Temfilcton, loe. s. cit. 469 La Flustre dentee, Blainv.

Actinolog. 450 Membranipora pilosa, Farre in Phil. Trans, an.

1837, 412, pi. 27, fig. 1-5.

Hub. On the lesser sea-weeds most abundant, and not uncom- monly on old shells.

Polypidora incrusting, merabrano-calcareous, irregular, follow- ing- the shape and form of the objects it grows upon, straw-yellow, thickish, porous, hairy : cells short, somewhat tubulous, with large roundish apertures ossified and toothed on the margin, the teeth short, sharp and rigid, and behind the mouth of each cell there is a very long tubular bristle which issues from a hollow base like a hair from its bulb. — Polypes with 12 tentacula, long in proportion to the body, thick and rather clumsy. Farre. " Polypus — tentacula circiter 20, sequalia et corpus sequantia, in campanse formam expandit." Pal- las.

When the polypidom encrusts the broad-leaved fuci or shells the texture is thinner and the cells more completely developed, and then their surface is perceived to be finely frosted. The small spines of the aperture are omitted in the figure of Ellis ; and that referred to for the variety dentata is imperfect and unfinished. Many believe this variety to be distinct in species, and specimens, sufiiciently cha- racteristic, can easily be produced in favour of the opinion, which, however, 1 am satisfied is erroneous.

M. pilosa often rises into small sponge-like fronds, cellular and hirsute on each side. " In frondes lubenter assurgit, utrinque cellu- losas crassiusculas, spongiosas ; primo simplices, lineares, obtusas ; deinde ramosas ; imo pinnato-multifidas fere nunquam poUice longio- res." Pallas.

282 Z. ASCIDIOIDA. Membranipora.

2. M. SPONGIOSA, aperture of the cells with several long setce.

Robert Brown.*

Flustra spongiosa, Templeton, in Mag. Nat. Hist. ix. 469.

Hab, " Found by Robert Browiij Esq. on the coast of Ballycastle," Templeton.

" Allied to the preceeding- : the mouths of the cells with several long setae. In pilosathe mouths of the cells are surrounded by several very short teeth, with only one hair-like appendage. In this species the teeth appear lengthened into long setaceous bristles." Temple- ton.

* The author of the " Prodromus Florae Novae HoUaiidise."

Fig. 46.

FAMILY XIII. ESCHARID^.

35. Flustra,* Linnaeus. Character. Polj/pidom plant-like, membranaceous, Jlexile, frondose or crustaceous, formed of cells arranged quincuncially in several series and in one or two layers : cells in juxtaposition, more or less quadrangular, fat, with a distinct border ; the aperture transverse, semilunar, valvular, subtermijial.'f — Poly- pes ascidian.

* Foliaceous, with cells on both sides. 1. F. FOLiACEA, cells narrow at the proximal and arched at the distal extremity., with scattered marginal denticles.

Plate xxxv. Fig-. 1, 2. Fucus marinus scruposus albidus telara sericeam textura sua semulans, Mor- ris. Hist. Plant, iii. 646, tab. 8, fig. 16. (bona.) Fucus telam lineam

sericeamve textura sua aemulans, Rail, Syn. 42, no. 9. Jussieiiin Mem. Acad. Roy. des. Sc. 1742, 298, pi. 10, fig. 3 Broad-leaved Horn- wrack, Ellis, Corall. 70, no. 2. pi. 29, fig. a, A. B, b Curious sea- weed, Hoohe, Microg. 140, pi. 9, fig. 2 ; and pi. 14, fig. 1. Eschara

foliacea, Lin. Syst. edit. 10, 804. Pall. Blench. 52 Flustra folia-

cea, Lin. Syst. 1300. Mull. Zool. Dan. prod. 253. Fabric. Faun. Groenl. 436. Ellis and Soland. Zooph. 12, pi. 2, fig. 8. Berk. Syn. i. 214. Turt. Gmel. iv. 663. Wern. Mem. i. 563. Turt. Brit. Faun.

• From the Saxon Flustrian, to weave : hence Flustra applied by Linnieus to these sea-mats.

f " The aperture of the cells is formed by a simicircular lid, convex exter- nally and concave internally, which folds down when the polypus is about to advance from the cell. The opening of this lid in the F. truncata, where it is very long, appears through the microscope like the opening of a snake's jaws, and the organs by which this motion is efl!ected are not perceptible. The lid of the cells opens and shuts in Flustric, without the slightest perceptible synchronous motion of the Polypi." Grant in Edin. New Phil. Journ, iii. 339.

284 Z. ASCIDIOIDA. Flustra.

209. Blumenb. Man. 272. Stew. Elem. ii. 433. Corall. 44. Lam.

Anim. s. vert. ii. 156. 2de edit. ii. 219. Grant in Edin. New Phil.

Jonrn. iii. Ill and 337. Flem. Brit. Anim. 535. Hogg's Stock. 36.

Stark, Elem. ii. 437. Johnston in Trans. Newc Soc ii. 26.3. Mag Nat.

Hist. iii. 483, fig. 120. Templeton in Ibid. ix. 469. Risso, L'Europ.

merid. v. 333 La Flustre foliacee, Blainv. Actinolog. 450, pi.

75, fig. 1. Hab. Common on hard ground, in a few fathoms water. Polypidom corneous, frondose, arising from a spreading base with a single plane of cells, about 4 inches high, of a uniform wood-brown colour, thickish, deeply divided into numerous broad segments ge- nerally somewhat narrowed at their origin, often bifid or trifid, some- times palmate near the apex which is slightly rounded ; the surface roughish, minutely reticulated : cells small, in semialternating rows, narrow at the base, dilated and arched at the top, the superior mar- gin armed with four stout conical processes shorter than the diame- ter of the celL The top of the cells is sometimes covered with a

small hollow globular pearly operculum opening downwards.

The segments vary very much in breadth, but are rarely, if ever, proliferous. " Varietas vulgatior frondibus latiusculis, dilatatis, ex- tremitate lata laciniosa. Rarior frondibus longis atque angustis. Perrara extremis frondium angustiorum latis et palmatis. Rarissi- ma subpiunatis aut latissimis margineque tantum divisis frondibus."

Pallas Hooke, in his celebrated " Micrographia," says, " for

curiosity and beauty, I have not among all the plants or vegetables I have yet observed, seen any one comparable to this sea-weed." When recent it exhales a pleasant scent, which Pallas compares to that of the orange, Dr Grant to^ that of violets, and which a friend tells me smells to him like a mixture of the odour of roses and geranium.

2. F. CHARTACEA, " cells sUghtly enlarged distalh/ ; margins smooth." J. Ellis.

Eschara papyracea utrinque cellefera, summitatibus securis aciei instar trun-

catis, Ellis, Corall. pi. 38, fig. 8 Flustra papyracea, Ellis and Soland.

Zooph. 13. Flem. Brit. Anim. 535. Lister in Phil. Trans, an. 1834, 384, pi. 12, fig. 3. Edwards in Lam. Anim. s. Vert. 2de edit. ii. 220.

La F. papyracee, Blainv. Actinolog. 451 F. chartacea, Turt.

Gmel. iv. 663. Turt. Brit. Fauii. 209. Stew. Elem. ii. 436. Bosc, Vers, iii. 141. Corall. 45. Risso, L'Europ. Merid, v. 333. Hah. Coast of Sussex, Ellis. Brighton, Lister. " The cells of this sea mat are of an oblong square figure, swel- ling out a little in the middle of each side. The openings of the cells are defended by a helmet-like figure ; from hence the polype- shaped suckers extend themselves. This sea mat is of a slender and deli, cate texture, like thin semitransparent paper, of a very light straw

Flustra. Z. ASCIDIOIDA. 285

colour It was first found on the coast of Sussex, adhering to s

shell. I have since met, on the same coast, about Hastings, in the year 1763, with several specimens, whose tops were digitated, and others that were very irregularly divided." Ellis.

As this is very certainly distinct from the F. papyracea of Linnaeus, I have preferred the name of Gmelin. Dr Fleming seems inclined to consider the species as a variety of the preceding. For my own part I know not how it is to be distinguished from that which follows.

3. F. TRUNCATA, cells Unear-oblong , with smooth margins.

Plate xxxv. Fig. 3, 4. Fucus marinus scruposus albidus augustior compressus, extiemitatibus quasi

abscissis, Rail, Syn. 43, no. 10. Morris. Hist. Plant. Oxoii. iii. 646,

tab. 8, fig. 17, opt Narrow leaved Horiiwrack, Ellis, Coral. 69, no.

l,tab.28,fig. 1, a. A, B Escliara foliacea /3, Zan. Syst edit. 10,804.

E. securifrons, Pall. Elench. 56. Flustra truncata, Lin. Syst.

1300. Mull. Zool. Dan. prod. 253. Ellis and Soland. Zooph. 11.

Berk. Syn. i. 214. Turt. Gmel. iv. 663. Warn. Mem. i. 563. Turt.

Brit. Faun. 209. Stew. Elem. ii. 436. Lam. Anim. s. Vert. ii. 157.

2deedit. ii 219- Corall. 44. Bosc, Vers, iii. 140. pi. .30, fig. 1. Risso,

L'Europ. Mend. v. 334. Grant, in loc cit. ill. Flem. Brit. Anim.

535. Hogg's Stock. 36. Johnston in Trans. Newc. See. ii. 264. pi.

12, fig. 1. Templeton in Mig. Nat. Hist. ix. 469 La Flustre tron-

quee, Blainv. Actinolog. 450 Hab. In deep water, very common.

Attains a height of four or five inches, very bushy, of a straw-co- lour, smooth, varnished when dry, rather thin in texture, origina- ting from a matted base formed of capillary fibres, which, by their union, compose a short stem that divides, after a dichotomous man- ner, into numerous flat narrowish segments, either linear or dilated upwards. From the edges of these there often sprout out wedge- shaped leaflets, affixed by a small pedicle, simple at first, but after- wards deeply bifid : the ends of all the segments are abruptly trun- cate. Cells linear-oblong, their septa unarmed, usually marked with a black dot towards the centre, which seems to be the remains of the shrivelled polype, and at some seasons covered with a hood-like operculum.

* * Foliaceous, with cells on one side only.

4. F. CARBASEA, Cells oblong^ narrorced and truncate below, the margin toothless. Dr Skene.

Plate xxxvi. Fig. 1, 2.

Flustra carbasea, Ellis and Soland. Zooph. 14, pi. 3, fig. 6, 7. Turt.

Gmet. iv. 663. Wern. Mem. i. 563. Turt. Brit. Faun. 209. Stew.

Elem. ii. 436. Lam. Anim. s. Vert. ii. 157. 2de edit. ii. 221. Boscy

286 Z. ASCIDIOIDA. Flustra.

Vers, iii. 141. Corall. 45. Flem. Brit. Anim. 535. Hogg's Stock. 36. Grant in Edin. New Phil. Jouin. iii, 111. Stark, Elem. ii. 437. John- ston in Trans. Newc Soc. ii. 264, pi. 9, fig. 4. Templeton ut. sup. cit. 469. Roget, Bridgew. Treat- i. 165, fig. 63, 64; and 172, fig. 69, 70. Dalyellin Edin. New Phil. Journ. xvii. 413; and in Rep. Brit. Assoc.

an. 1834, 60-3 La F. voile, Blainv. Actinolog. 451.

Hab. On shells from deep water. From Aberdeen, Skene. Leith shore, Mr Parsons. Not unfrequent at Seaton, Hartlepool, Whitburn, and other places on the coast of Durham, J. Hogg. Coast of Berwickshire, not uncommon, G. J. Ireland, Templeton.

Polypidom frondose, fixed by a small disk, narrow at the base with thickened margins, dilating- upwards and becoming very broad in proportion to the height, which at most is about two inches, thin, yellowish brown, deeply divided, the segments broad and somewhat rounded on the apex. Cells on one side only, large, and smooth. Polypes with about 22 tentacula, which are " nearly a third of the length of the body, and there appear to be about 50 cilise on each side of a tentaculum, making 2200 cilise on each polypus. In this species there are more than 18 cells in a square line, or 1800 in a square inch of surface, and the branches of an ordinary specimen pre- sent about 10 square inches of surface ; so that a common specimen of the F. carbasea presents more than 18,000 polypi, 396,000 tenta- cula, and 39,600,000 cilise." Grant.

5. F. SETACEA, cells in 2 or 3 rows, oval, with a setaceous

bristle. Rev. Dr Fleming.

Flustra Ellisii, Fleming in Wern. Mem. ii. 251, pi. 17, fig- 1 — 3

F. setacea, F/em. Brit. Anim. 536. La F. setacee, Blainv. Actinolog.

451. Hah. " Along with Cellepora cervicornis, from deep water, Zet- land," Dr Fleming.

" Height nearly two inches ; branches linear, not the tenth of an inch in diameter ; substance firm, brittle ; the base consists of small tubes, which by their union, form the branches, dorsally carinated by the union of the tubes, which, diverging to each side and dividing form two denticles and a long bristle, the latter serrated on one side ; cells oblique." Dr Fleming.

6. F. Avicui.ARis, cells in 4 or Jive rows, oblong, with a strong conical spine at each side of the aperture. J. Ellis.

Plate xxxvi. Fig. 3, 4. Corallina cum appendiculis lateralibus avium capitum forma, Ellis, Corall.

pi. 38, fig. 7. Cellularia avicularia /?, Pall. Elench. 68. Flustra

avicularis, Soverhy Brit. Misc. ii. 21. pi. 7L Turt. Brit. Faun. 210. Flem. Brit. Anim. 536. Johnston in Trans. Newc. Soc. ii. 265 La

Flustra. Z. ASCIDIOIDA. 287

F. aviculaire, Bluinv. Actinolog. 451 F. angustiloba, Lam. Anim.

s. Vert. ii. 158. 2de edit. ii. 222 F. capitata, Hogg's Stock. 36.

Crisia flustroides, ZamoMr. Corall. Flex. 141. Corall. Gl.

Hab. Attached to other corallines and old shells in deep water. Torhay, Dr Coldstream. Cullercoats, Northumberland, Mr Alder. Berwick Bay, G. J. Cork harbour, J. V. Thompson.

Usually about an inch in height, csespitose and fan-like, or spread out circularly, of a cinereous colour, merabrano-calcareous, brittle when dry, deeply divided in a dichotoraous manner into narrow thin plane segments, truncate at the end, formed of four or five series of oblong cells, capped with a hollow globose pearly operculum seated between the spines, of which there is one on each side of the circu- lar aperture. The opercula are so numerous that they give to the upper surface the appearance of being thickly strewn with orient pearls : the under surface is even and longitudinally striated, the number of striae corresponding to the number of rows in which the cells are disposed.

7. F. MURRAY ANA, cells multiserial, ovate, the margin armed icith 6 or 8 spines shorter than the diameter of the cell. Mr Bean.

Plate xxxvi. Fig. 5, 6. Flustra Murrayaiia, Bean, MSS. named " after Dr Murray, a scientific and zealous naturalist of Scarborougb."

Hah. In deep water. Scarborough, very rare, Mr Bean.

This pretty species grows in entangled spreading masses which are rooted to the object of attachment by numerous long thread-like tu- bular fibres, wrinkled when dry, and apparently always pullulating from the side or inferior surface of a marginal cell. Polypidom scarcely an inch in height, of a light colour and thin membranous texture, dichotomous, spreading, the segments plane, narrow wedge- shaped, truncate, the upper surface roughish with the cells, which are disposed in the usual quincuncial manner, but are more elevated than in any other species ; the under surface glistening, striate : cells uni- lateral, so large that their figure is perceptible to the naked eye, ovate, truncate above with a short hollow spinule at each angle, and there are from 4 to 6 rather longer spinules protecting the margin of the elliptical aperttire — I have seen only Mr Bean's fine specimen, which is accurately delineated in our figure. The species is very distinct from any hitherto described.

* * * Crustaceous. 8. F. MEMBRANACEA, cells ohlong, icith a short blunt spine at each corner. J. Ellis.

Plate xxxvii. Fig. 1, 2, 3.

288 Z. ASCIDIOIDA. Flustra.

Flustra membranacea, Lin. Syst. 1301. Fabric Faun. Groeiil. 437, no.

446. Mull. Zool. Dan. prod, 253. Ellis and Soland, Zooph. 18.

Turt. Gmel. iv- 665. Wern. Mem. i. 563. Turt. Brit. Faun. 21 C

Stew. Elem. ii. 437. Bosc, Vers, iii. 144. Corall. 47. Hogg's Stock.

36. Flem. Brit. Anlm. 536. Johnston in Trans. Newc. See. ii. 265.

La F. membraneuse, Blainv- Actinol. 450 Fl. telacea. Lam. Anira.

s vert. 2de edit, ii- 223. Grant in loo. s. cit. iii. Ill La naem-

branipore membraneuse, B!ainv. Actinol. 447. Hab. On the frond of Laminaria digitata. common. Polypidom forming- a gauze-like incrustation on the frond of the sea-weed, spreading irregularly to the extent of several square inches, in general, thin, and closely adherent, but sometimes becoming thick- ish, and then capable of being detached in considerable portions ; cells very obvious to the naked eye, oblong, quadrangular with a blunt hol- low spine at each angle. In many specimens there are some anoma- lous processes, a quarter of an inch in height, scattered over the sur- face : they arise from within the cells, are simple, horny and tubular, but closed at top. Ellis conjectured they were ovaries, but the con- jecture is certainly unfounded. — When the polypes are all protruded they form a beautiful object under the microscope, from their num- bers, their delicacy, the regularity of their disposition, and the viva- city of their motions, now expanding their tentacula into a beautiful campanulate figure, now contracting the circle, and ever and anon retreating within the shelter of their cells. The tentacula are nume- rous, filiform, white and in a single series.

9. F. LINEATA, cells oval, separate, the margin armed with several short equal spirious denticles. Professor Jameson.

Plate xxxvii. Fig. 4. Flustra lineata, Zzn. Syst- 1301. Mull. Zool. Dan. prod. 253. Fabric. Faun. Groenl. 437. Turt. Gmel. iv- 665. Corall. 46. Jameson in

Wern. Mem. i. 563 La F. lineee, Blainv. Actinol. 450 F. spi-

nifera, Johnston in Trans. Newc. Soc. ii. 266, pi. 9, fig. 6 F. hir-

ta? Bosc, Vers, iii. 144. Risso, L'Europ. Merid. v. 334. Corall. 49. Hob. On stones at low-water mark in Berwick Bay, G. J. Ork- ney Islands, Jameson.

Polypidom membranous, of a horny texture, yellowish-brown, rough, closely adnate, thin, spreading irregularly : cells scarcely visi- ble to the eye, separate by a space not equal to the cell in breadth, the marginal teeth stout and somewhat inclined inwards.

10. F. ? carnosa, ^^ sid)stancejleshy ; cells remote, aperture contracted, armed at the top with spinous processes." Jameson.

Plate xxxvii. Fig. 5. 3

Flustra. Z. yVSCIDIOIDA. 289

Flustra liisi)ida, Fabric. Faun. Groenl. 438 Jameson in Wern. Mem. ''. 563. Flem. Brit. Anim. 537- Johnston in Trans. Newc. Soc. ii. '260,

pi. 9, fig. 7 La F. hispide, Blainv. Actinolog. 450.

Hub. " Investing- Fucus serratus ; everywhere common," Flem- ing. Leith shore, Jameson. Berwick Bay, at low water mark.

" Substance thick, tough, full of mucus, brown ; base of the cells, where attached, contiguous and angular ; at the surface the cells are ovate, the aperture lunate. Polypi with an enlarged head, and from 20 to 30 tentacula," Fleming. — As the Flustra hispida of Pallas is unquestionably a diffex'ent species, it has become necessary to adopt another specific name.

1 1. F. TUBERCULATA, membrano-colcareoiis ; cells oval with tioo short spines at the sides of the aperture and one above it.

Fleming.

Plate xxxiv. Fig. 9. Flustra tiiberculata ? Bosc, Vers, iii. 143 " F. dentata ? Mull. Zoo).

Dan. iii. tab. 95, fig. 1, 2." F. unicornis? Fleming, in Edin. Phil.

Journ. ii. 87. Flem. Brit. Anim. 536. Johnston, in Trans. Newc. Soc.

ii. 266. Fl. membranacea? Lam. Anim. s. Vert. 2de edit. ii. 225. Le

Membranipore unicorne? Blainv. Actinolog. 447 La Flustre uni-

come, Ibid. 450. Hah. On stones within low water-mai'k, Fleming. Frequent in Berwick Bay.

Polypidom in the form of a thin closely adherent greyish- white subcalcareous crust, reticulated like a piece of gauze to the naked eye, spreading circularly : cells quincuncial, short, oval, with a large ovate aperture armed with two short spinous teeth inclined inwards, the margin somewhat thickened : in the space between the cells and above the aperture there is a conical process which appears to be per- forated on the top.

This is more calcareous in its texture than any of the preceding- species, and hence assumes a white colour when dried. When per- fect and young, the denticles to the aperture are very evident, (Fig. a), but in old or exposed specimens no vestige of them can be disco- vered. (Fig. h.) At one time I had nearly concluded that these specimens belonged to different species, but the timely possession of a perfect polypidom prevented the commission of the error, for in it the cells towards the margin have all the characters of a, and those near the centre the character of b. I have not seen MuUer's figure, but the description of F. tuberculata given by Bosc agrees with the the first state of the species ; and it appears to be probable that on the second state is founded the F. unicornis of Fleming.

T

290 ASCIDIOIDA. Cellularia.

Flustra arenosa, Ellis and Soland. Zooph. 17. Steiv. Elem. ii. 437-

Bosc, Vers, iii. 142. Millepora arenosa aiiglica, Raii, Syn. i. 31

English Sandy Millepore, Ellis, Corall. 74, no. 5, pi. 25, fig. e

Escharalutosa, Pall. Elench. 37. Alcyonium arenosum, Turt. Gmel.

iv. 364. Turt. Brit. Faun. 207 According to Mr Boys this "isun-

doubtedly the nidus of some marine animal, as I have found the cells en- tire, with eggs in each." Lin. Trans, v. 231. Mr J. Hogg has proved that it is the nidus of Nerita monilifera. Lin. Trans, xiv. 318, &c.

36. Cellularia,* Pallas. Character. Polypidom calcareous or memhrano-calcareousy confervoid, divided sidtdichotomously, the divisions Jiarrow, com- posed of two alternating series of ohlong sessile cells on a single plane ; the apertures terminal, oblique, facing one way, and usual- ly covered with an opercidum. — Polypes ascidian,

1. C. ciLiATA, erect, dichotomous ; cells alternate, turbinate,

with an oblique open aperture armed on the outer edge with 4 or

5 long spines. — Ellis.

Plate xxxviii. Fig-. 1-2.

Ciliated Coralline, Ellis, Corall. 38, no. 5, plate 20, d, D Sertularia

ciliata, Lin. Syst- 1316. Berk. Syn. i. 220. Turt. Gmel. iv. 685. Turt. Brit. Faun. 217. Wern. Mem. i. 565. Stew. Elem. ii. 448 Cellu- laria ciliata. Pall Elench. 74. Flem. Brit. Anim. 340. Hogg's Stock.

35. Cellaria ciliata, Ellis and Soland. Zooph. 24. Bosc, Vers, iii.

133. Lam. Anim. s. Vert. ii. 139. 2de edit. ii. 186 Crisia ciliata,

Corall. 60. Tempkton in Mag. Nat. Hist. ix. 468 La Bicellaire ci-

liee, Blainv. Actinolog. 439.

Hah. Parasitical on corallines and the roots of Fuci, not uncom- mon. " Mare Anglicum ; ubi, in Fucis, Spongiis, Sertulariis, para- sitica crescit," Pallas. Leith shore, Jameson. Scarboroug-h, Mr Bean. Rare on the coast of Berwickshire, G. J. " Found on Fu- cus siliquosus, and on other corallines" in Ireland, Templeton.

Tufted, about half an inch in height, very slender and delicate, hispid, pellucid white, calcareous, dichotomously branched. The cells are rather widely alternate, turbinate, with the apertures evert- ed, patulous, and armed with long spines which are apt to be broken off. The spines appear to be tubular. A sacate j)early lid covers the mouth of many cells ; and at or near the base there is, on some of them, a small anomalous appendage something like a bird's head. The pellucidity and delicacy of this species, with its pearly lids scat-

* From cellula, diniir.utive of cella, a cell-

CEM.ur,AniA. Z. ASCIDIOIDA. 291

tered over the branches, render it a remarkably beautiful object un- der the microscope.

2. C. SCRUPOSA, creeping, dichotomous ; cells alternate with a plain aperture, " an amjie projecting on the outward side of each." Ellis.

Plate xxxviii. Fig 5, 6. Creeping stony Coralline, Ellis, Corall. 38, no. 4. pi. 20, c, C. Cellifeious

Coralline with angular edges to its cells, Ellis, in Phil. Trans, xlviii. pi.

13, no. 7. Phil. Trans, abridg. x. 493, pi. 12, fig. 7, K, L Sertula-

ria scruposa, Lin. Syst. 1315. Turt. Gmel. iv. 686. Berk, Syn. i.

220. Turt. Brit. Faun. 216. Wern. Mem. i. 363. Stew. Elem. ii. 448.

Cellularia scruposa, PoW. Elencb. 72. Flem. Brit. Anim. 339

Cellaria scruposa, Ellis and Soland. Zooph. 23. Bosc, Vers, iii. 132, pi.

29, fig. 7. Lam. Anim. s. Vert. ii. 141. 2de edit. ii. 192. Johnston in

Trans. Newc. Soc. ii. 261, pi. 11, fig. 3 Crisia scruposa, Corall.

Templeton in lib. cit ix. 469 La. B. raboteuse, JBlainv. Actinolog.

439. Hub. On the roots of Laminaria digitata, on FlustraR, corallines and old shells, common.

This frequently covers a space about an inch square, the branches diverging and creeping along the surface or the entangled roots of sea-weed, to which they are attached by simple tubulous root- like fibres pullulating from the plane inferior surface. The branches are rather broad, dichotomous, of an earthy brown colour, brittle when dry. Within the cells I have occasionally seen one, or sometimes two, nearly globular orange-coloured ova.

3. C. REPTANS, creeping, dichotomous ; cells alternate with an oblique aperture armed with short spines at the top. — Ellis.

Pi/ATE xxxviii. Fig. 3-4.

Creeping Coralline, Ellis, Corall. 37, pi. 20, no. 3, fig. b- B. Sertularia

reptans, Lin. Syst. 1313. Fabric. Faun. Groenl. 44-5, no. 439. Turt.

Gmel. iv. 685. Tvrt. Brit. Faun. 217. Stew. Elem. ii. 448 S.

repens, Berk. Syn. i. 220 Cellularia reptans. Pall. Elench. 73.

Flem. Brit. Anim. 540. Hogg's Stock. 35 Cellaria reptans, Ellis

ioiA. Soland. Zooph. 23- ^osc, Vers, iii. 132. Lam. Anim. s. Vert. ii. 141. 2de Edit. ii. 191. Stark, Elem. ii. 439. Johnston in Trans. Newc.

Soc. ii. 262 Crisia reptans, Coral. 60. Risso, I'Europ. Merid. v.

318. Templeton in Mag. Nat. Hist. ix. 469 — La Bicellaire rampante, Blainv. Actinol. 439. Hah. On Flustra foliacea and other submarine bodies, common. Similar to the preceding in form and mode of growth, but its spread- ing tufts cover in general a larger space, and are more densely matted.'

292 Z. ASCIDIOIDA. Cellularia.

The radical tubes are flexuous, corneous, and divided at the extremity into two or three small knob-like processes. Branches linear, plane, jointed at their origins, composed of two rows of semialternate oval cells, with an oblique terminal aperture level with the surface, and armed with several short brittle spines. Ellis represents only two spines to each cell, and Pallas follows him in his description, but they are commonly more numerous. Stretched across the mouth of the cells there may occasionally be observed, in dried specimens, an ir- regularly veined pellucid membrane, undoubtedly the remains of the polype's sac or tunic. Opercula are also to be seen over some cells, but these are not common.

4. C. ? AvicuLARiA, erect^ dichotomous ; the cells with two

spines at the aperture. Ellis.

Plate xxxvi. Fig. 7, 8. Bird's-head Coralline, Ellis. Corall. 36, no. 2, pi. 20, fig. a, A- Cellularia

avicularia. Pall. Eleiich. 68. Hogg's Stock. 35. Sertularia a\'icu-

laria, Lin. Syst. 1315. Berk. Syn. i. 220. Wern. Mem. i. 565. Turt.

Brit. Faun. 216. Stew. Elem. ii. 448. Cellaria avicularia, Ellis and

Soland. Zooph. 22. ^osc, Vers, iii. 131. Lam. Anim. s. Vert ii. 141.

2de edit. ii. 191. Johnston in Trans. Newc. See. ii. 262 Crisia

avicularia, Lamoiir. Cor. Flex. 141. Corall. 61. Templeton, in Mag. Nat. Hist. ix. 468. Hab. Parasitical on other corallines in deep water. From the sea-coast near Dublin, Ellis. " Mare inter Angliam et continen- tem terram," Pallas. Not very uncommon at Hartlepool, J. Hogg. Leith shore, not common, Jameson. Scarborough, on stones &c. at low water, not uncommon, Mr Bean. Ireland, Templeton.

Polypidom caulescent, erect, bushy, from one to two inches in height, membrano-calcareous, silvery or glassy greyish-white, brit- tle when dry, attached by a fibrous root, the stalk composed of nu- merous interwoven fibres ; primary branches alternate, flabellate, di- vided dichotomously into many narrow linear flat segments, which are rough and cellular on the upper or inner side, but smooth and longitudinally striate underneath. Cells in two semialternating rows, coalescent, opening on one plane, oblong, flat, their parietes thin and pellucid, a strong spine at each of the superior angles, the aperture subterminal, transverse, generally covered with a large globular pearly operculum placed between the spines ; and at the external side there is in many a curious appendage which Ellis has aptly com- pared to a " bird's head, with a crooked beak, opening very wide." These appendages, of unknown use, are about one fourth the size of the cell, and, when the coralline is in a living state, are continually

AcAMARCHis. Z. ASCIDIOIDA. 293

moved \ip wards and downwards with the regularity of a pendulum. The polypes have apparently twelve tentacula.

The cells have the characters of Acamarchis or Flustra rather than of Cellularia. IMany naturahsts make the zoophyte a vari ety of Flustra avicularia, but Mr Bean and Milne Edwards dissent from this associa- tion. The principal distinction between them lies in the dissimi- larity of their habit : in the shape of the cells I do not perceive any noticeable difference, but in this I have never seen more than two spines at the top of each cell, while in the Flustra I have seen four on some cells, though certainly many of them are armed with two only.

5. C. HOOKERi, ^^ cells rounded, diverging, projecting." — Sir

W. J. Hooker.

Cellularia Hookeri, Flem. Brit. Anim. 339 La Bicellaire de Hooker,

Blainv. Aclinol. 460.

Hab. " Found by Dr Hooker at Torquay, 1812," Fleming.

" H eighth upwards of an inch, dichotomously branched, branches straight, stiff, brittle, divaricate ; the cells are protuberant dorsally, and their rounded top is nearly free, projecting laterally, giving the edge a remarkably jagged outline, and the pearly ovaria are rounded." Fleming. — This is probably syonymous with Cellaria denticulata of Lamarck, Anim. s. vert. ii. J 37.

37. Acamarchis,* Lamouroux. Character. Polypidom plant-like, subcalcareous, attached hy fibrous radicles, bushy, dichotomously branched, the branches composed of a double series of semialternate oblong cells whose apertures occupy nearly one side and face one way, usually pro- tected by an operculum. — Polypes ascidian.

1. A. neritina, " cells quadrangular, lengthened, with a

truncated summit, the outer angle projecting." — Miss Blackburne.

Remarkable Coralline, Ellis in Phil. Trans, abridg. x. 345, pi. 8, fig. a, A.

G. Ellis, Corall. 33, pi. 19 Sertularia neritina, Lin. Syst. 1313.

Turt. Gmel. iv- 683. Stew. Elem. ii. 448 Cellularia neritina,

Pall. Elencb. 67. Flem. Brit. Anim. 339 Cellaria neritina, £ffis and

Soland. Zooph. 22. Bosc, Vers, iii. 131. Lam. Anim. s. vert ii.

140. 2de edit, ii- 190 Acamarchis neritina, Corall. 38, pi. 3, fig. 2.

Risso, I'Europ. Merid. v. 318. Blainv. Actinolog. 439, pi. 77, fig. 3. Tem- pleton in Mag. Nat. Hist. ix. 469- Hab. On the English coast, very rare. " I possess a specimen

" The name of one of the daughters of Oceanus,

•294 Z. ASCIDIOIDA. Acamahchis.

from the collection of the late Dr Walker, which he received from Miss Blackburne from the coast of Cheshire," Fleming. " Found in Dublin Bay and Belfast Lough," Templeton.

" Height several inches, dichotomously divided, spreading ; the cells are narrow, rather diverging, and more than the half of the outer summit is free ; the pearly helmet-shaped ovaria opening transversely, were at one time considered by Ellis as the young of Neritae." Flem- ing.

2. A. PLUMOSA, cells linear-oblong^ with a spine at the outer and upper angle ; the aperture elliptical, entire. Doody.

Plate xxxix.

Corallina pumila erecta ramosior, Raii, Syn. i. 37, no- 20, tab. 2, fig. 1. Ellis, in Phil. Trans, abridg. x. 346, pi. 8, fig. h, B-B Soft feather- ed coralline, Ellis, Corall. 33, no. I, pi. 18, fig. a, A Sertularia

fastigiata, Lin. Syst. 1314. Fabric. Faun. Grcenl. 445. Turt. Gmel. iv. 684. Berk. Syn. i. 219. Turt. Brit Faun. 216. Wern. Mem. i.

565. Stew. Elem. ii. 448 Cellularia plumosa. Pall. Elench. 66.

Hogg's Stock. 35 C. fastigiata, Blumenh. Man. 273. Flem. Brit.

Anim. 539 Cellaria plumosa, Ellis and Soland. Zooph. 21. Bosc,

Vers, iii. 131. Lam. Anim. s. Vert. ii. 140. 2de edit. ii. 190. Crisia

plumosa, Corall. 62 C. fastigiata, Templeton in Mag. Nat. Hist. ix.

468 La Bicellaire plumeuse, Blainv. Actinolog. 459.

Hah. " Not uncommon beyond low water-mark," Fleming. Leith shore, Jameson. In deep water at Scarborough, common, Mr Bean. Eare in Berwick Bay, G. J. " Common on the coast" of Ireland, Templeton.

Polypidom attached by fibrous roots, subcalcareous, caulescent, erect, from 2 to 4 inches high, very much branched, the branches panicled, dichotomous, with linear or filiform segments ; cells oblong with a short pointed spine on the superior outer angle, smooth, pel- lucid or somewhat crystalline, marked always with a black or orange- coloured dot near the centre, the remains of the dried polype ; ovaries pearly, globular or pear-shaped, placed over the apertures.

In habit this fine species is sometimes like Sertularia argentea, but in general it is more tufted and bushy. Specimens occur without an ovary on any cell, while others are loaded with them ; and in one of the latter sort I found some of the segments of the branches com- posed of a triple series of cells. The whole polypidom is often co- loured of a pink or pui'plish hue. In an old condition the cells be- come obsolete, and the habit of the species so altered, as to render its detection in this guise somewhat difficult to the inexperienced. Dr Fleming does not adopt this genus, which Blainville is also of

4

Farcimia. Z. ASCIDrOIDA. 295

opinion differs too little from Cellularia to be admitted. There is certainly much sameness in the characters of these genera, but there is a recognizable difference in the form of the cells, more particularly in the aperture, liker in Acamarchis to that of Flustra than of Cellu- laria, which warrants us in laying hold of it as a line of separation in a case where the dissimilarity in habit is very obvious. The agree- ment in this respect between the species seems no less patent, al- though it has not been hitherto perceived.

Farcimia,* Fleming. Character. — Polypidom rooted^ plant-like, calcareous, di- chotoinous ; the branches cylindrical, regularly jointed, with im- ynersed rhomboidal cells diverging from the axis, disposed in quin- cunx, and opening on the surface ; the apertures lateral, plain, non-operculate.

1. F. &!s.hico'R^i\, articulations nearly cylindrical ; the cells rhomboidal, plain.

Plate xxxvii. Fig. 6, 7.

Corallina fistulosa fragilis, Raii, Hist. i. 65 Corallina fistulosa fragilis,

internodiis praelongis laevibus, albis, farciminum mode cateiiatis, Pluken.

Phytog. pi. 26, fig. '2 Bugle Coralline, Ellis, Corall. 46, no. 1, pi.

23. Escbara fistulosa, Lin. Syst. edit. 10, 804 Tubularia fistu- losa, Lin. Syst. 1302. Berk. Syn. i. 214. Turt. Gnael. iv. 666. Turt.

Brit. Faun. 210. Stew. Elem. ii. 438 Cellularia Salicornia, Pall.

Blench. 61 Cellularia farciminoides, Ellis and Solajid. Zooph. 26.

C. salicornia, Lam. Anim. s. Vert. ii. 135. 2de edit. ii. 176. Stark,

Elem. ii. 439. Bosc, Vers, iii. 129, pi 28, fig. 6, Corall. 55- Lamour.

Zooph. 5. Risso, L'Europ. merid. v. 317 La Cellaire salicorne,

Blainv. Actinol. 455, pi. 77, fig. 1 Farcimia fistulosa, Flem. Biit.

Anim. 534. Johnston in Trans. Newc. Soc. ii. 266 Salicomiaria

fistulosa, Templetonin Mag. Nat. Hist. ix. 469 Isis hippuris ? Fa6rjc.

Faun. Groenl. 427.

Hab. On corallines and old shells from deep water, not uncommon. Torquay, Dr Coldstream. CuUercoats, Northumberland, Mr Jos. Alder. Dunstanborough, Mr Emhleton. Coast of North Durham and Berwickshire, occasionally, G. J.

One of the finest of British zoophytes. Polypidom from 1 to 3 inches high, white, calcareous, fibrous at the base, erect, regularly dichotomous ; branches erecto- patent, straight ; joints constricted,

* From Farcimen — a sausage, in allusion to the manner in which the inter- nodes are joined. The genus is synonymous with the Cellaria of Lamouroux, and with the Salicornaria of Cuvier, Reg. Anim. iii. 303.

296 Z. ASCIDIOIDA. Retepora.

often blackish and emitting fibrous radicals ; the intervening spaces long, cylindrical, frequently swollen near the upper end, covered all round with lozenge-shaped immersed cells, disposed in quincunx, and radiating from the centre.

In a weak mixture of muriatic acid and water, the calcareous por- tion of the polypidom is entirely removed without any other altera- tion in its form and structure, and we learn from the experiment that the joints are connected together by capillary corneous tubes, equal in number to the series of cells. These tubes cannot be traced through the immediate spaces, but from the circumstance of their being hollow, it seems not unreasonable to infer that they may na- turally be filled with an irritable pulp, and be the medium of com- munication between the cells and polypes of the different interspaces. The branches are not tubulous or fistular, as Blainville has properly remarked ; whence the impropriety of the Linnaean trivial name, the retention of which only tends to the perpetuation of error.

Under this species Pallas has the following interesting observation : " Celerrime hanc Celhdariam crescere, saltem celerius embryone Squall, docuerunt ova Squali Promontorio merid. Africes allata, in quibus pl^ntulas plures semipollicares observavi, quanquam foetum adhuc immaturum continerent."

38. Retepora,* Lamarck. Character. — Coral foliaceous^ stony, fragile, netted: cells opening only on the upper or inner side, short and not prominent, — Polypes ascidian.

1. R. RETICVI.ATA, polypidom latticed, ivavy and convolute, the upper side warty and very porous. Rev. William Borlasse.

Millepora retepora, Borl. Cornw. 240, pi. 24, fig. 8 Millepora reticu- lata, Lin. Syst. 1284. Fabric. Faun. Groenl. 433. JEllis and Soland. Zoopb. 138 M. frondipora, Pall. Elench. 241 Retepora reti- culata. Lam. Anim. s. Vert. ii. 182. 2de edit. ii. 273. Bisso, L'Eiirop.

Merid. v. 343. Flem. Brit- Anim. 531. Stark, Elem. ii. 435 Re-

tepore reticulee, Blainv. Actinolog. 633 Frondipore reticule. Ibid.

406, pi. 69, fig. 1.

Hab. Deep water, rare. Cornwall, Borlasse.

" Expanding to the extent of 2 or 3 inches ; more or less cup- shaped, waved, uniting ; the lobes are oval, regular, the intervening spaces supporting two or three pores in oblique rows. This species

" From Rete and to^oc, i. e. a " a porous net-work."

3

EscHARA. Z. ASCIDIOIDA. 297

is very distinct from the R. celiulosa, with which it has been con- founded." Fleming.

2. R. CELLULOSA, polypidom reticulated^ umbilicate , Junnel- shaped, tvavt/, celluliferous on the inner side ; the pedicle short, subtubular. Ellis.

Vignette No. 46, page 283. Retepora eschara marina, Fer. Imperat. Hist. Nat. 630, c. fig. Ellis, Corall.

72, pi. 25, fig. d, D, F. Millepora retepora. Pall Elench. 243.

M. celhilosa, Lin. Syst. 1284. Turt. Gmel. iv- 637. Turt. Brit. Faun. 205. Jameson in Wern. Mem. i. 560. Steiv. Elem. ii. 427. Bosc, Vers, ii. 34-3, pi. 25, fig. 5. Cavol. Polyp, mar. 73, tav. 3, fig. 12-14.

Blumenb. Man. 270 M. foraminosa, Fllis and Soland. Zooph. 138.

pi. 26, fig. 2 Retepora celiulosa, Lam. Anim. s. Vert. ii. 182. 2de

edit. ii. 276. Stark, Elem. ii. 435. Risso, L'Europ. Merid. v. 343.

Johnston in Mag. Nat. Hist. vii. 6-38, fig. 69 La Retepore dentelle

de mer, Blainv. Actinolog. 433, pi. 76, fig- I .

Hub. Deep water, rare. Shetland islands, and in the island of Fulah, Jameson. Scarboroug-h, Mr Bean.

Polypidom about an inch in height, affixed by a hollow, thick, and A'ery short stalk, which expands into a shallow cup with unequal wav- ed and sinuous margins ; pure white, calcareous and beautifully reti- culated, the meshes about a line in length, oval, subequal, regular and divided by celluliferous spaces, rather wider than their own short- est diameter ; the cells immersed, quincuncial, leaning, with the apertures looking upwards, a little prominent, round, with a small tooth on the distal edge ; they open only on the superior or inner aspect, for the under surface of the polypidom is imperforate and al- most smooth.

39. Eschara,* Ray. Character. — Polypidom membrano-calcareous, inflexible, brittle, expandimj in the form of foliaceous porous lamellce, vari- ously folded and anastomosiny, and consistiny oftioo layers of op- posite cells : cells immersed, coalescent, horizontal to the plane of axis, openiny on both surfaces in quincuncial pores protected with an opercidum. — Polypes ascidian.

1. E. FOLIAGE A, plates foliaceous, ivindiny, unitiny irreyu- larly andforminy sinuous cavities. Dillenius.

Plate xl.

* Ey;(;aga, the scar from a burn.

298 Z. ASCIDIOIDA. Eschaka.

Eschara retiformis, JRaii, Syn. i. 31. Flem. Brit. Anim. 531 Stony

foliaceous Coralline, Ellis, Corall. 71, no. 3, pi. 30. fig. a, A. B. C.

Borl. Cornw. 239, pi. 24, fig. 6 Millepora fascialis, Lin. Syst. 1283.

Stew. Eleni. ii. 427 M. foliacea, Ellis and Soland. 133. Turt.

Ginel. iv. 636. Turt. Brit. Faun. 205. Steiu. Elem. ii. 427. Hogg's

Stock. 37. Bosc, Vers, ill. 341, pi. 25, fig. 4 Eschara fascialis,

Pall. Elench. 44 E. foliacea. Lam. Anim. s. Vert. ii. 175. 2de edit.

ii. 266. jRisso, L'Europ. Merid. V. 341. ^-far^, Elem. ii. 436. Blainv. Actinolog. 428, pi. 75, fig. 3. Milne Edwards in Ann. des. Sc. Nat. Part. Zool. vi. 36, pi. 3, fig. 1.

Hah. On various parts of the English coast in deep water. " Conchis testisve adnascitur et circa Cockbxish in Sussexia saepe reperitur," Dillenius. Isle of Wight, Ellis. Cornwall, Borlasse. Devonshire, Dr Coldstream.

This curious polypidom attains a large size being often 3 or 4 inches high, and frona 1 2 to 20 in its greatest diameter. It may be described as a broad membrane twisted into winding folds, leaving large sinuosities and cavernous interstices : it is very light and floats in water, crisp when dry, membrano-calcareous, cellular, of a yellow- ish-browu colour, roughish and punctured with the numerous pores which open on both sides. The membrane is less than a line in thickness, and consists of two layers of cells separated behind from one another by a thin plate down the middle. The cells open ob- liquely by contracted roundish apertures disposed in a quincunx order on the surface, and which, more especially when recently formed, are often covered by a small operculum. When a portion is macerated in diluted muriatic acid, it retains the original form, but becomes soft and flaccid from the subtraction of the carbonate of lime. The cells are liable to all the changes of form which have been indicated, in an appended note, as the results of age upon these polypidoms in general.

2. E. FASCIALIS, '• expansions narrow^ compressed, branched,

occasionally united" Pallas.

Italian Coral, Ellis, Corall. 72, pi. xxx. fig. b Eschara fascialis var. a.

Pall. Elench. 42. Lam. Anim. s. Vert. ii. 175. 2deedit. ii. 267. Flem.

Brit. Anim. 531 Millepora tcenialis, Ellis and Soland. Zoopb. 1.33.

M. fascialis, Turt. Gmel. iv. 636. Berk. Syn. i. 211. Turt. Br. Faun.

204. L'Eschare a bandelettes, Blainv. Actinolog. 428. Milne-Ed-

toards in Ann. des. Sc. Nat. Part. Zool. vi. 43- pi. 4, fig. 1.

Hab. Deep water. Isle of Wight, Pallas.

" This Millepore grows in very irregular masses, but always pre- serves the same habit of growing ; that is, the branches are flat, nar- row, and regularly subdivided : they coalesce, twist, and branch out

EscHARA. Z. ASCIDIOIDA. 299

again, leaving- certain hollow spaces between them ; their cells are much smaller, though of the same shape with the cells in the folia- ceous Millepore" (E. foliacea). Solander. — Pallas maintains that it is merely a variety of the preceding ; but Milne-Edwards thinks it ought to be retained distinct, for its peculiarity of ramification, and the narrowness of the divisions, do not depend on age, and seem to indicate a specifical difference. The cells in both are alike.

Fig. 47.

FAMILY XIV. ALCYONIDUL^..

40. Alcyonidium, * Lamouroux. Character. Polypidom fiesliy^ lohed or crustaceans ; cells immersed^ pentagonal, icith Jihro-corneous parietes, the aperture terminal, simple, contractile, "f- — Polypes ascidian.

1. A. GELATiNosuM, polypidom variously lohed or branched,

subcylindrical or somewhat compressed^ the sui'face smooth and

even. Johnson. :|:

Plate xli. Fig. 1-3. Fucus spoiigiosus nodosus, Ger. Herb. emac. 1570, no. 10, fig. Raii. Syn.

i. 49, no. 42. Alcyonium, seu fucus nodosus et spongiosus, Ellis

Corall. 87. no. 5, pi 32, fig. d. D. Alcyonium ramosum nioUe, mul-

tis polypis obsessum, Bart. Opusc. Subs, i, 40, tab. 1, fig. 5, A. B

Alcyonium gelatinosum. Pall. Elench. 353. Lin. Syst. 1295. Mull. Zool. Dan. prod. 255, no. 3082. Ellis and Soland. Zooph. 176. Turt Gmel. iv. 633. Jameson in Wern. Mem. i. 563. Turt. Brit. Faun. 207- Stew. Elem. ii. 432. Bosc, Vers, iii. 157. Flem. Brit. Anim. 517. La- moiir. Cor. Flex. 350. Corall. 249 L' Alcyon gelatineux, jB/ainj;. Ac-

* From Alcyonium, to which the name implies a resemblance.

f According to Dr Farre the retractile portion of the cell, or that which con- stitutes the base of the polype, is composed of a series of stout short setae.

I Johnson, Thomas, born at Selby in Yorkshire ; a Lieut. Colonel in the royal army during the civil wars, created M. D. Oxon, in 1643, in considera- tion of his loyalty and learning j killed in 1644, " at which time his worth did justly challenge funeral tears ; being then no less eminent in the garrison for his valour and conduct as a soldier, than famous through the kingdom for his excellen- cy as an herbalist and Physician." See Pultcney's Sketches, i. p. 128. &c.

Alcyonidium. Z. ASCIDIOIDA. ;3Ul

tinolog. 525, pi. 92, fig. 1 Ulva diaphana, Eng. Bot. pi. 2G3. Wifh.

Bot. Arrang. iv. 121. Hull, Brit. Fl. ii. 312. Lam. and Decand. Flor.

Fran9. ii. 6. Alcyonidium diaphanum, Lamour. Soland. Zooph. 71.

Gray Brit. PL i. 353. Hook. Fl. Scot. ii. 75. Loud. Encycl. PI. 928,

no. 15045 Al. flavescens, Lout/. Encyclop. PI. 928, no- 15046

Halodactylus diaphanus, Farre in Phil. Trans, an. 1 837, 405, pi. 25 and 26-

Hab. Deep water, attached to old shells and stones. " Margate in the island of Tanet," Johnson. " Prope INIargate in insula Tha- net Cantio adjacente primum observavit Johnsonus, postea D. Dale in insula Mersey, and D. Doody in insula Shepey," Ray, " Satis copiose reperitur posteriore insula, sed long-e copiosius observatur in insula Thamesis ostio altius adjacente, Grain vocata," Dillenius. " In the month of August 1752, there was so great a quantity of it driven near Sheerness, in the Isle of Sheppey, as to clog the fisher- men's nets, and interrupt their fishing," Ellis. Isle of Anglesea and Walney, Hudson. Lowestoffe, Woodward. Leith shore, Jameson, where Dr Coldstream tells me it is sometimes very abundant. Very rare in Berwick Bay, G. J. Orkney islands, Dr Pat. Neill.

The polypidom is attached by a narrow base to the substance from which it grows, and rises to the height of from 6 to I2 inches, '* some- times attaining the length of two or three feet." It resembles a com- pact sponge, but is more pellucid and gelatinous ; sometimes simple and entire, usually branched ; the olour, as is well observed in Eng- lish Botany, varying from a very pale brown, almost like that of wet sea-sand, to a clear yellow ; in the latter case the polypidom has exactly the appearance of barley-sugar of the paler kind. The sur- face is smooth and speckled with minute dots produced by the dark bodies of the inhabitant polypes, which protrude their ten- tacula through angular apertures, aud are all placed immediately un- derneath the skin, for the centre of the polypidom is a clear transpa- rent jelly traversed with corneous fibi'es forming a very wide and ir- regular net-work. The polypes are so intimately connected with their cells that it is almost impossible to remove them without mu- tilation. They have 16 filiform tentacula, disposed in a single circle, which are capable of being retracted within the cell. " The ten- tacula are sixteen in number, (occasionally fifteen,) fully two-thirds the length of the body of the animal, and extremely slender and flexible. When expanded they are frequently seen to roll up closely upon themselves, even down to their base, the revolution taking place either inwardly or outwardly, and in one or more arms at the same time. Their full expansion affords a more perfect campanulate form than is usually met with in this class, each of the arms having

302 Z. ASCIDIOIDA. Alcyonidium.

a slight curve outwards towards its extremity, which gives to the whole a very elegant appearance. It is remarkable that in some specimens the arms are much shorter on one side of the body than on the other." Farre.

" The stomach is not furnished with a gizzard in this species. The intestine forms a considerable elbow at its origin, and is short and wide, terminating not as in other cases near the tentacular ring, but about midway up the body, at a point opposite the base of the setae.

" A very singular organ was frequently observed, consisting of a little flask-shaped body situated between the base of two of the arms, and attached to the tentacular ring by a short peduncle. The cavity in its interior is lined with cilia which vibrate downwards towards the outer, and upwards towai'ds the inner side ; it has a narrow neck and a wide mouth, around which a row of delicate cilia are constant- ly playing. No flow of fluids could ever be detected through it, nor did the use of carmine assist in showing with what parts the ca- vity in its interior might communicate. From the circumstance that it is more frequently absent than present, it cannot be an organ of vital importance to the animal : and it is too intimately blended with the sides of the tentacula, and too constant in its position to be re- garded as a parasite. Does it indicate a diff"erence of sex ?" Farre.

This production was first described by Johnson, the editor of Ge- rarde's Herbal. His description, which is characteristic enough, is as follows : " This is a very succulent and fungous plant, of the thicknesse of one's thumbe ; it is of a dark yellowish colour, and buncheth forth on everie side with many unequal tuberosities or knots : whereupon Mr Thomas Hickes being in our companie did fitly name it Sea ragged Stafi"e." — It was afterwards observed on the southern coasts of England by Dale and Doody ; and Ray introduced it into his synopsis of British Plants as a fucus. Ellis at first suspec- ted it to be the spawn of some shell-fish, but (whether relying on the authority of Pallas, who had seen the polypes, or upon subsequent original observations, is uncertain,) he ultimately came to a correct conclusion, for in his history of Zoophytes he says, " This is found at particular seasons full of minute papillaj which send forth polypes." The fact was overlooked ; and on the authority of Ray and Hudson, botanists continued to rank it in the vegetable kingdom, where it re- mained until very recently. Even I^amouroux considered it at first as a sea-weed, but he had the fortune afterwards to detect the poly- pes which he describes as having a cylindrical body and 12 tentacula ; and the description which Dr Fleming has given is essentially the same. If no error has crept into their calculation, the speri(>s must

Alcvomdium. Z. ASCIDIOIDA. 303

be distinct from ours, for a very careful examination has satisfied me that the tentacula are 16 in number.

D'Orbigny says that the Ulva diaphana of the Flore Fran9aise " n'est autre chose qu'un amas de series d'ceufs d'une espece de gas- teropode nu." Mem. du Museum, vi. 181. The description, how- ever, so evidently belongs to the Alcyonidium before us, as to make it almost certain that this remark has originated in some misapplica- tion of it.

2. A. HIRSUTUM, polypidom variously divided, compressed^ the surface covered with minute conical papillce or polype-cells. Fleming.

Plate xlii. Fig. 1, 2.

Alcyonium gelatinosum, Fabric. Faun. Groenl. 447 A. hirsutumt

Flem. Brit. Anim. 517. Johnston in Zool. Joum. iv. 418. and in Trans. Newc. Soc. ii. 231, pi. 9, fig. 1. L'A. vein, Blainv. Actinolog. 525.

Uab. Parasitical on various sea-weeds, at low-water mark, very common on the coasts of Scotland and North of England. Coast of Devonshire, 3Ir Jos. Alder.

Polypidom variously divided, often proliferous, sometimes sub-cy- lindrical, commonly flattened and palmate, of a dirty straw-yellow colour, often partially stained with red, and marked with numerous yellowish circular spots irregularly disposed. It is thickish, some- what cartilaginous, and to the naked eye resembles a compact sponge. When viewed through a common magnifier, the surface is seen to be covered with close-set conical transparent papillae, each of which is a cell containing a polype with 16 long filiform tentacula, and in its structure resembling the polype of a Flustra. The yellowish spots, mentioned in the description, are produced by clusters of ova lying- imbedded in the cellular texture. These are opaque milk-white, large enough to be easily visible to the eye, of a roundish figure, but not all of them alike, for some are ovate, and others incline to a heart-shape, rather compressed, the surface uneven. The ^^g is not clothed all over with cilia, but there is a fringe of cilia encircling it ; these cilia appear to be of a yellowish colour, and to be hooked near the apices, (wood-cut No. 7, page 51.) They are of equal size and shape, and all inclined in one direction, moving with a uniformity and quickness which is admirable and very pleasing to the beholder. When the e^^ is at rest, their velocity is not diminished, excepting at the will, so to speak, of the ovum, for it may be seen to become slower and less constant, to cease entirely for a moment, and again be renewed with its former force. The e^^ at rest will at once start

304 Z. ASCIDIOIDA. Alcyonidium.

from its place, and swim about hither and thither as it were endow- ed with volition, turning on its axis frequently, moving- sometimes on one side, sometimes on its edge, when the cilia become invisible. I have seen the cilia, when the ovum was at rest, suddenly disappear, withdrawn as it seemed within themselves, or under the opaque mar- gin, and again be quickly protruded. By their motion they drive a current of water over the surface, but this current has certainly not an uninterrupted circular motion — it is rather a flowing to the sur- face, and a cm'rent from it, or as Raspail would express it, an inspi- ration and expiration of water. — When lying still, I have seen the eggs exhibit the most unequivocal signs of irritability, contracting and di- lating themselves. The ovum appears to be formed of a firm elastic coat or shell filled with agranular matter ; it is opaque, excepting on ■ the margin, under which the cilia appear to originate.

3. A. ECHiNATUM, polypidom incrusting dead univalve shells, the surface muricated with rough prominerit papillce or cells. Mr Montagu.

Plate xlii. Fig. 3, 4. Alcyonium echinatum, Flem. Brit. Anim. 517. Johnston \n Trans. Newc

Soc. ii. 251, pi 9, fig:. 2 L'A. herisse, Blainv. Actinolog. 525.

Hub. Parasitical on Buccinum undatum and similar univalve shells ; not uncommon. Stevenston, Ayrshire, Rev. D. Landsbo- rough. Berwick Bay.

" This species incrusts dead univalve shells exclusively ; and is about the one-twentieth of an inch in thickness. When first taken out of the water, it is soft and spongy, but becomes rigid on drying." The surface in this state is muricated with spinous papillce, somewhat less than a line in height aud rough with minute prickles pointing upwards and arranged in rows. The polypes appear to have only 12 tentacnla.

4. A.? PARASiTicuM, inc7'usting corallines, earthy, the sur- face even and porous. Rev. Dr Fleming.

Plate xli. Fig. 4, 5.

Alcyonium parasiticum, Flem. Brit.' Anim. 518 L'A. parasite, Bhiinv-

Actinol. 525. Hab. Parasitical on Sertulariadse and old shells. Hartlepool, ,/. Hogg. On the valve of an old Venus islandica dredged from deep water at Scarborough, 3Ir Bean. Berwick Bay, rare.

This production spreads up the stem and branches of various flexi- ble corallines coating them with an incrustation of an earthy appear- ance, from a line to the eighth of an inch in thickness. The sur-

Cliona. Z. ASCIDIOIDA. 305

face is porous or cellular, even, roughish, the pores roundish or pen- tagonal, distinct and separate, but not arranged in rows, or in any re- gular fashion ; the interior is irregularly cellular, and earthy. — None of the mineral acids have any effect on this substance, nor does it absorb water like a sponge, but when dropt into a glass of water, it sinks to the bottom and lies there unaltered. No siliceous nor calcareous spi- cula enter into its structure, but it seems to be entirely composed of particles of sand cemented together with mud or clay. It has there- fore no character of a proper polypidom, although the conformation and regularity of its cells prove it to be the work of some gregarious animal.

41. Cliona, * Grant. Character. Polypidom amorphous^ Jieshy, containing sili- ceous spicula and perforated with ramified canals. — Polypes mi- nute, retractile, placed in tubular papillce.

1. C. CELATA. R. E. Grant, f

Plate xlii. Fig. 5, 6.

Cliona celata, Grant in Edin. New Phil. Journ. i- 78 ■ ii. 183, pi. 2, fig. 7,

(the spiculum.) Flem. Brit. Anim. 516. Stark, Elem. ii. 421

La Clione cachee, Blainv. Actinolog. 527. Hab. In perforations of the shell of the oyster (Ostrea edulis) : abundantly in the oyster beds at Prestonpans, off Inchkeith, and in the roads of the Firth of Forth, Grant.

This sponge-like zoophyte inhabits and fills up the worm-like holes in old oyster-shells. The part which projects beyond the orifice of the hole is papillary, about a line in height and about the same in breadth, of a yellowish colour, tubular, and either closed or widely open at the apex. In texture it resembles the Halichondria papil-

' " I have termed this genus Cliona, (from KXitce, claudo), from its most ob- vious and remarkable property of retracting and shutting the papilla when irri- tated ; and the above described species, the only one I have met with, is named celata, from its concealed and secure habitation within the substance of oyster- shells." Grant.

f Dr G. is a native of Edinburgh, where he received his education, and gra- duated M. D. in 1814, when he was President of the Royal Medical Society. His Thesis was " de Circuitu Sanguinis in Foetu." Shortly afterwards his at- tention was turned to natural history ; and his researches into the nature of sponges and zoophytes laid the foundation of that reputation which readily se- cured him the chair of Zoology and Comparative Anatomy in the London Uni- versity, on its first establishment, — a chair which he continues to fill with the most distinguished ability.

U

306 Z. ASCIDIOIDA. Cliona.

laris, and, like it, is almost entii'ely composed of siliceous spiciila, which are straight and in shape like a pin, but from their brittleness few can be separated from the mass in an entire state, and we seldom observe one with the enlargement that takes the place of the head. I have examined specimens in oysters brought to market, and having placed these in sea water, other fellow parasites of their own class soon gave evidence of their being yet living and active, but I had never the pleasure of seeing the polypes of this production.

" The Cliona in the living state consists of a soft, fleshy, granular and distinctly irritable substance, of a greenish yellow colour, tra- versed, like many other zoophytes, with minute and regularly formed spicula. Its form depends on that of the cavities which it fills ; it insinuates itself into their minutest ramifications, and adheres so close- ly to their smooth parietes, that it cannot be separated without tearing. The parts of the Cliona which project through the holes on the sur- face of the shell are tubular ; and on removing the outer layers of the shell, we can perceive several empty canals winding and ramify- ing from these tubular papillae, through the body of the zoophyte. During the months of March and April, when these observations were made, numerous small yellow ova were seen in the vicinity of the canals, agreeing much in their form, colour, size, and mode of distribution with those of the Spongia papillaris and Spongia pani- cea, which were then nearly in the same stage of advancement. The projecting tubular papillae possess a complicated structure, and a high degree of contractile power, and exhibit a singular series of appear- ances, when the zoophyte is attentively examined while at rest in pure sea water. When under water, the papillae are seen projecting from the apertures of the shell, sometimes to the length of a line and a half ; they present a wide circular opening in their centre, and a rapid current of water issues constantly from them, conveying occasional flocculi of a grey membranaceous matter. But on being touched with a needle, or withdrawn from the water, the opening gradually closes, the current ceases, and the whole papilla continuing slowly to con- tract, is withdrawn completely within the aperture of the shell. The papillae, viewed in their contracted state, present a smooth, rounded, shut extremity ; but when they begin to advance beyond the surface of the shell, their extremity becomes flat and slightly dilated, assumes a villous appearance, with open fissures, radiating from the centre to the margin of the papillae, and at length a minute circular opening is perceived in the centre of the villous surface. The papilla advances from the shell, and its central opening enlarges in proportion to the healthy state of the zoophyte, and the purity and stillness of the wa-

Cliona. Z. ASCIDIOIDA. 307

ter ; its flat downy radiated surface gradually diminishes by the widen- ing: of the central opening-, till only thin margins are left around the onflce, and the current is again seen to play briskly from it. In re- cent specimens of the Cliona dredged from an oyster-bed near the shore at Prestonpans, and examined under the most favourable cir- cumstances on the coast, I have twice observed polypi of extraordi- nary minuteness and delicacy placed around the margin of the orifice and which kept in constant motion, advancing and withdrawing themselves into the substance of the papilla, m hile the current flowed from Its central opening. The polypi were perfectly invisible to the naked eye in an ordinary light and position ; but by suspending the Chona in a crystal jar with clear water, and placing it between the eye and a candle, or the sun, they were seen like filaments of silk or asbestus constantly rising and sinking on the margin of the papilla. On cutting oflf a papilla, and placing it under a microscope in sea wa- ter, the polypi continued their motions, and were seen to consist of a long, slender, transparent, cylindrical, tubular fleshy body, at the far- ther extremity of which were placed about eight short broad tentacu- la, slightly dilated at their free ends, which were constantly inflecting and extending themselves irregularly, while the polypi advanced or retreated. In two entire and fresh specimens, the polypi continued visible and in motion for more than twenty-four hours in ajar of wa- ter at Prestonpans ; but I have not yet succeeded in perceiving them in any of the numerous specimens which I have preserved alive in the water procured from Newhaven." Professor Grant. The spi- cula " are about the fourth of a line in length, and appear through the microscope as minute curved pins spread irregularly through the whole fleshy substance of the animal :" they are " slender, cylin'drical, tubular, slightly curved, shut at both ends, a little fusiform in the' middle, acutely pointed at one end, and terminated by a small hollow round head at the other." Grant.

Dr Coldstream writes me that, judging from the form of the spi- cula, he believes he possesses another species of Cliona from Bute, perforating the walls of the limpet (Patella vulgata.)

FAMILY XV. LIMNIADES.

42. Cristatella,* Cuvier. Character. Polypes with about 60 tentacula, affixed with- in a floating membranaceous sac, variously aggregated ; a sepa- rate oriflce to each ; gevimiparous or oviparous, the ova spinife- rous.

1. C. MucEDo. Sir John Graham Dalyell. f

Plate xliii. Cristatella mucedo, Cuv. Reg. Anim. iii. 296. Gervuis in Ann. des Sc. Nat. part. Zool. vii. 77, n. s. Turpin in ibid. vii. 65, pi. 2 and 3, fig.

1-7 C. vagans, Lam. Anim. s. Vert. ii. 97. 2de edit ii. 110. Blainv.

Actinolog. 489 and 678, pi. 85, fig. 7. Bosc, Vers, iii. 180, pi. 30, fig.

9. Stark, Elem. ii. 442 C mirabilis, Dahjell in Edin. New. Ph il.

Joum. xvii, 414 ; and in Rep. Brit. Assoc, an. 1834, 604. Hab. " An inhabitant of the fresh waters of Scotland," Sir J. G. Dalyell.

" Perfect specimens occur from six hnes to twenty-four in length, by two or three in breadth, of a flattened figure, fine translucent green colour, and fleshy consistence. Some of the shorter, tending to an elliptical form, may be compared to the external section of an ellip- soid ; but those of the largest dimensions are Hnear, that is, with pa- rallel sides and curved extremities." — " The middle of the upper and the whole of the under surface are smooth ; the former somewhat convex, occasioned by a border of 70 or 80, or even of 350 individual polypi, disposed in a triple row. Their number depends entirely on the size of the specimen, — increasing as long as it grows."

" This product is endowed with the faculty of locomotion, either extremity indifferently being in advance, but its progression, uncom- monly slow, seldom exceeds an inch in twelve or twenty -four hours. Each of the numerous polypi, though an integral portion of the com- mon mass, is a distinct animal, endowed with separate action and sen- sation. The body, rising about a line by a tubular fleshy stem, is crowned by a head which may be circumscribed by a circle as much

• The diminitive of cristata — crested, t The author of a very interesting work on the Planariae.

Cristatella. Z. ASCIDIOIDA.- 309

in diameter, formed as a horse-shoe, and bordered by a hundred ten- tacula. Towards one side the mouth, of singular mechanism, seems to have projecting- lips and to open as a valve, which folds up within, con- veying the particles which are absorbed to the wide orifice of an intes- tinal organ which descends, perhaps in a convolution, below, and re- turns again to terminate in an excretory canul under the site of the tentacula. Probably the whole race of Cristatellse is distinguished by a similar conformation."

" The polypus is a very vivacious animal, quickly retreating for security when alarmed, and rising to expand in activity. Though each be endowed with independent life, sensation, and all the motions that can be exercised without actual transition, the whole are sub- jected to the volition of the sluggish mass in respect to progression :

— they arc borne along with it." " A specimen having been cut

transversely asunder, each portion seemed to recede by common consent ; but both survived, as if sustaining no injury. Neither is any polypus affected by the violence offered in its vicinity.

" Twenty, thirty, or more lenticular substances, of considerable size and in the most irregular arrangement, imbedded in the flesh, are exposed through the translucent green of the animal. Its death and decomposition towards the end of autumn liberate them to float in the water. Subjected to the microscope, or, indeed to the naked eye, their convex surfaces prove brown, the circumference yellow, and begirt with a row of spines terminating in double hooks. Each is an ovum of the Cristatella with a hard shell, and occupied by yel- lowish fluid contents." " In 3 or 6 months the ovum gapes at

one side to allow the protrusion of an originating polypus, which by a remarkable provision of nature now floats reversed, with the head downwards, to ensure absorption of the liquid element below. On quitting the ovum it attaches itself to some solid substance by the base, then disproportionately large, from which a second polypus quickly rises, then a third, and a fourth ; and thus with others. In earlier stages the Cristatella mirabilis seems to be of a circular figure, and in its most mature state there is a margin projecting beyond the root of the polypi." Dalyell.

To illustrate this description of Sir J. G. Dalyell, the only naturalist who has observed the species in Britain, I have given copies of the beautiful figures of M. Turpin in Plate xliii, for there can surely be scarce a question of the identity of the continental and British zoophyte. Turpin's figures, it is to be noticed, were drawn from young or slightly developed specimens ; a mature polypidora with its 300 individuals must indeed present

310 Z. ASCIDIOIDA. Cristatella.

to the naturalist a spectacle of such singular curiosity and beauty as perhaps can meet its supei'ior or rival in no other creature. I am unwilling to borrow, from the memoirs of the foreign authors, any additions to Sir J. G. Dalyell's short history, for I am aware of the confusion to which such a practice has occasionally led, but no harm can arise from the mention of some particulars which are evi- dently generical. I may state then, that the tentacula are cihat- ed like those of other ascidians ; the intestine has an oral and anal aperture, the latter with a medial position ; and there is no trace of any organ like what, in some other families of the order, has been reckoned an ovary. The egg, according to M. Turpin, forms a small flattened sphere with a papillous surface slightly incrusted with cal- careous matter. The centre is of a dark reddish-brown or vinous colour, the margin more transparent and yellowish, proving that the egg is vesicular, — the exterior circle marking out the thickness of the cocoon or shell, and the more opake disk the part occupied with the embryotic fluid. About 16 rough spines radiate stiffly from the circumference : they are tubular, yellow, terminated with from two to four crotchets, and apparently vary in length, for they arise alternately from the edge and from the surface a Httle behind this.* The egg is filled with an albuminous granular fluid analogous to the vitellus or yolk, for in it the foetus is perfected after a period which probably depends, in a great measure, on the temperature of the sea- son in which they are laid. The time of birth having arrived, the shell opens in two gaping halves, as an oyster opens its valves, to permit the escape of the young polypus, which enters on its existence complete in all respects, either a single individual, or with one or two others, less mature, pullulating from the sides.

One of the most interesting facts ascertained by M. Turpin is that the eggs before exclusion, and immediately after, are oval or lenticular, and entirely/ free of the spines which roughen them at a later stage. Hence an easy solution of a question touching the man- ner of escape from the mother, which, before this discovery, seemed incapable of being eff"ected without a painful laceration from their bristling armature. This alteration in the structure of the egg is very remarkable, although not singular, for the eggs of several mites

* According to M. P. Gervais this is not the case, — the spines orignate sole- ly from the line of junction between the marginal band and the disc ; — " du point de contact de cet anneau et du corps disciforme partaient sur I'une des faces les crochets doiit j'ai parle. Je reconnus depuis que I'autre face presentait aussi les appendices en crochets, mais qu'ils y etaient moins allonges."

Cristatella. 7. ASCIDIOIDA. 311

are known to undergo somewhat similar changes. The eggs float in the water from their lesser specific gravity, but often they be- come attached by their spines to the filaments of confervae, <S:c. where they float until the young are hatched and aff'ord to them an im- mediate place of rest.

M. Turpin has ascertained that some varieties of silex contain im- mense numbers of the ova of the Cristatella and Alcyonella, preserv- ed in entire perfection. Ann. des Sc. Nat. Part. Zool. vii. 120, plates 6 and 7.

43. Alcyonella,* Lamarck. Character. Polypidom Jixed^ ina-ustingf or Jloating, in the form of an irregular sponge-like mass composed of vertical aggregated 7nembronaceous tubes opening on the surface. — Poly- pes ascidian, the mouth encircled loith a single series offiUform tentacula depressed or iricomplete on one side : eggs coriaceous, smooth.

1. A. stagnorum.

Plate xliv.

Variation *. Sponge-like, massive Alcyonium fluviatile, Bosc, Vers, iii.

159. Corall. 250. Ephydatia Gibbsii, Gray, Brit. PI. i. 353

Alcyonella stagnorum, Lam, Anim. s. Vert. ii. 102. 2de edit. ii. 116. Stark, Elem. ii. 442. Lamour. Soland. tab. 76, fig. 5—8. (bad.) Teale in Trans. Leeds Phil, and Lit. See. i. 116, pi. 12, and in Mag. Zool.

and Bot. i. 293 A. fluviatilis, Raspail in M^m. de la See. d'Hist.

Nat. de Paris, iv. 130, pi. 12 — 16. L' Alcyonella des etangs, Blainv.

Actinolog. 491, pi. 85. fig. 8.

Variation /S. Polypidom lohed or stellate — Polypes a panache, Tremb. Mem.

210, pi. 10, fig. 8—9. Reaum. Mem. des Insect, vi. pref. Ixxvi The

Bell- Flower- Animal or plumed Polype, ^aAer, Employ. Micros. 306, pi.

12, fig. 15 — 22. Hydra campanulata, Zin. Syst. edit. 10, 817

Tubularia erystallina, Pall. Elench. 85 T. campanulata, Lin. Syst.

1303. Berk. Syn. i- 215. Shaw Nat. Misc. x. pi. 354. Turt. Gmel. iv. 668. Turt. Brit. Faun. 211. Adams on the Microscope, 449, pi. 22,

fig. 32. Bosc, Vers, iii. 92. Blumenb. Man. 272 T. reptens, Bosc,

Vers, iii. 93 Plumatella cristata. Lam. Anim. s. Vert. ii. 107. 2de

edit. ii. 122. Stark, Elem. ii, 441. Blainv. Actinol. 490. PI. campa- nulata, Risso, L'Euvop. Merid. v. 308 Naisa reptans, Corall. 99,

pi. 6, fig. 4. Cristatella campanulata, Flem. Brit. Anim. 518

C. paludosa, Dalyell in Rep. Brit. Assoc, an. 1834, 606. Hab. Stagnant waters, especially in such as are tinctured with iron

• A diminutive from Halcyon. The sponge -genus Alcyonelliim of Quoy and Gaymard, being of subsequent creation, cannot be retained.

3V2 Z. ASCIDIOIDA. Alcyonella.

in solution : their developement chiefly in autumn. Habitat ad Angliam, Linnceus. About Chelsea, Dr Shmv. Not uncommon in Hyde-park, and Green-park, in the centre of London, J. E. Gray. Near Leeds, Mr Teale. Near Hovvick, Northumberland, Mr R. Emhleton. On leaves in ponds in Scotland, Sir J. G. Dalyell.

Polypidom, when at maturity, in large amorphous compact masses, soft, compressible, and somewhat elastic, of a blackish green colour, irregularly lobulated or sinuous on the surface, which has a lubricous appearance, and is more or less apparently porous. The mass is com- posed of subcylindrical tubes rising from the base to the surface, near- ly parallel, connected by, or permeating, a transparent firm jelly-like substance, with which the tubes appear to be also partially filled. The tubes are simple or uubrancbed, and open outwardly by a round- ish or pentagonal aperture, which is closed by a thin membranous cover. The walls of the tubes are of the same thin membranous character, pellucid, colourless, or tinted with green, and without any visible vessels ; they contain innumerable lenticular ova of a dark brown colour, about half a line in their longest diameter, very hard and incompressible, but in drying the centre becomes depressed and more transparent than the edges. These singular ova are quite smooth,* and arranged in rows in the tubes, though not very regularly : they are more abundant near the surface than at the base of the polypi- dom, and exist in such amazing numbers as to excite surprise at the seeming productiveness of an animal which appears to be very partial- ly diff'used, and is very capricious in its appearance even in ponds fa- vourable for its growth, — swarming in one season, of rare occurrence in the next, and perhaps then for years lying dormant until some un- discovered cause hatches the <i^^ and renews its pristine fertility. When freed from the mass, the greater number of the ova swim on the surface of the water, but some sink to the bottom.

To this description, derived from specimens in a recent, but not living condition, sent me by Mr Embleton, I add the following par- ticulars derived fi'om Mr Teale's valuable paper. A good idea of the polypes will be obtained by reference to figures 5, 6, of Plate xliv, which are reduced copies of Raspail's. It is organically connected with the mass, the tube forming its tunic, from which the animated body issues by a process of evolution similar to that which developes the horn of a snail. When developed, the head projects a short way,

* M. Meyeii says, on the contrary, that the envelope of the ovum is covered with very fine vibratile cilia. Bull, des Sciences Nat. xviii, 313. Has not Meyen mistaken the ova or seeds of the Spongilla for those of the Alcyonella ? lor niKloubtedlv the ova of the latter are smooth.

Alcyonella. Z. ASCIDIOIDA. 313

and is crowned with a " beautiful expansion of tentacula, about fifty in number, arranged in an unbroken circle, which is, however, de- pressed into a deep concavity on one of its sides, so as to produce the appearance of a double row of tentacula in a horso-shoe form. About one thousand six hundred polypes are situated on a square inch of sur- face of the mass, consequently the number of polypes" in one speci- men which weighed 17 ounces, and measured 14^ inches in circum- ference, " may be computed at one hundred and six thousand, and the tentacula at five millions three hundred and twenty thousand I" The mouth is, as usual, in the centre of the crater formed by the tenta- cula, and is the entrance to an alimentary canal that, descending in the body, swells out into a stomach, and then bends to gain an up- ward course, having its termination exterior to and underneath the indenture in the tentacular circle. " The lower portion of the stomach is of a bright brown colour, longitudinally striated. The colour ap- pears to depend upon the alimentary materials which it contains, and the vertical striae are probably produced by folds in the organ. On lacerating the stomach, the brown matter escapes in the form of in- numerable minute grannies. A sort of vermicular motion is some- times observed in the stomach."

The ova ai'e generated in that portion of the polype-tubes which is prolonged from the stomach through the common mass, (fig. 2,) not germinating in any certain point, but from all the gelatinous sides. ♦' Those which are perfectly matured are of a dark reddish-brown colour. Others of the same size have their external envelope opaque and white ; others are somewhat smaller and translucent, whilst some are very minute and perfectly transparent. The mature and imma- ture ova appear scattered indiscriminately throughout the tube. The ova ai*e stated by Raspail to occur in a double series ; I have, how- ever, almost invariably found them in a single row. M. Raspail also says he has been able to see the small filament which connects the

ova to their containing membranous tube." There appears to be no

duct or aperture through which the ova can escape, their liberation being apparently dependent on the decomposition of the body. This is of two kinds : " In the first, the papilla which during life closes the tube, dies and becomes softened, ragged, and flocculent, and in this state no longer forms a barrier to the exit of the ova. In No- vember, many of the specimens were seen in this condition. On ex- amining the surface of the polypiferous masses, they were seen co- vered with ragged shreds of membrane instead of the well-defined conical papillae' or expanded polypes. In the second stage, air is dis- engaged from decomposition of tlie contents of the horny tube or

314

Z. ASCIDIOIDA.

Alcyonella.

ovary. If a recently dead specimen in which the papillae are reduced to the state above described, be examined with the lens, a succession of air-bubbles are seen frequently escaping from the horny tubes. By the successive formation and ascent of these bubbles, the ova which at this period are loose and floating in the tubes, are gradually elevated and conveyed to the exterior. In November, many of the specimens were seen with air-bubbles and ova successively escaping, and the external surface was covei'ed by ova thus conveyed to the ex- terior. Those specimens which were black and putrid, and appeared to have been dead some time, exhibited the horny tubes nearly de- void of ova. After a time the horny basis itself becomes softened, and appears to undergo decomposition. During the following spring, according to the evidence of Vaucher and Raspail, the horny envelope of each ovum separates into two lateral halves adhering on one side as by a hinge. From these valves a small gelatinous tubercle pro- jects, which soon expands into a distinct polype, and gradually be- comes elongated into a tubular form. From the sides of this tubu- lar polype, small gelatinous buds soon appear, and these again be- come developed into distinct polypes ; the tubular parietes gradually become consolidated, and form the horny basis of the mature Al- cyonella."

Fig. 48.

Si

^

Alcyonella. Z. ASCIDIOIDA. 315

The Alcyonella, if I have correctly sorted the synonynaes, was disco- vered by Trembley in the spring of 1741. It seems necessary to give a copy of his figures here, (wood-cut, No. 48,) since on them is founded the second variation of the species, and they exhibit it in a guise very different from that represented in our Plate xliv. His history of the animal is marked with much of that excellence which distinguishes the inquiries of this naturalist. He correctly describes the connec- tion and relationship between the polype and the common mass ; the arrangement of the tentacula, and the structure of the alimentary canal, although he failed to detect the anus. He overlooked the cilia of the tentacula from employing magnifiers of too low a power, and attributed the whirlpools created in the water by their play to the motion of the tentacula themselves, which he says were also used separately to force the aniraalcular prey into the mouth. He knew that the polypes were not contractile, and believed their retraction within the tubes was dependant on the play of a muscular thread which descended from the body in the common mass. The gemmi- parous mode of increase in the polypidom is also detailed with some minuteness, but he had not seen the ova, at least in a state of ma- turity.*

Immediately after Trembley's discovery, Reaumur and Bernard de Jussieu found this animal in the neighbourhood of Paris, and detect- ed its ova, from which they saw the young issue. Reaumur's ac- count of the growth of the compound animal appears to me to cor- roborate the opinion of the sameness of the Plumatella and Alcyonella. He says that while the polypes a panache are still very young, they increase in the same manner that the locomotive polypes do, with one difference only which it is essential to note, since it explains clearly the formation of those polypidoms that resemble plants. The tube of a newly evolved polype continues as it were permanently grafted upon the tube of that which has given birth to it : from the polype tube he has seen germinate by little and little another which contained a nascent polype ; he has seen this tube elongate itself, and the polype tenant at length show itself outwards to follow out the destined tenor of its life. Scarcely had a few days passed until this again gave birth to a young one whose tube was in connection with

* It is even doubtful whether the bodies he took for imviature ova were really so. " J'ai vu dans plusieurs des Polypes a panache, sur lesquels j'ai fait mes obser\-ations, de petit corps spheriques de differentes grandeurs, blancs et transparens. J'ai seulement soup(;onne que ces petits corps etoient des oeufs, mais je n ai pas eu occasion d'cxaminer si ce soup9on etoit fonde, ou non. ' p. 219.

S16 Z. ASCIDIOIDA. Alcyonella.

the parent's, and continued so. In this manner he has seen files of tubes and polypes formed, grafted the one on the other ; he has seen these unite in polypidoms which there would have been no hesitation in regarding as plants, if he had not followed them in the progress of their growth, and if he had not had the opportunity of convincing himself that the whole was but the assemblage of cells constructed and developed one after another, and inhabited by animalcules.

Baker next described the animal in what Raspail considers its se- cond stage of developement ; and as his description is derived from native specimens, 1 insert it entire, anxious to give as much com- pleteness as possible to the history of a zoophyte which appears un- der so many phases, and regarding which there still exist considerable doubts. "I was first informed," Baker says, "of this creature bymyin- dustrious friend Mr William Anderson, towards the end of the year 1743, as his letters shew : and in the year 1744, it was taken notice of by Mr Trembley,who gave it, in his Memoirs, the name of the Polype d Panache, or the Plumed Polype. My friend, who discovered it in his searches for the Polype, called it the Bell-Flower Animal ; and after favouring me with his own observations, sent me some of the creatures themselves, which, living with me for several mouths, I had suflBcient time and opportunity to examine and consider them. And as there seems some little difference between those in my keep- ing, and what Mr Trembley describes, they may possibly be of an- other species, though of the same genus.

" This is one of the many kinds of water animals which live as it were in societies ; of which some sorts hang together in clusters, but can detach themselves at pleasure ; whilst others are so intimately join- ed and connected together, that no one seems capable of moving or changing place without affecting the quiet and situation of all the rest. But this creature forms as it were an intermediate gradation between the other two, dwelling in the same general habitation with others of its own species, from whence it cannot entirely separate itself; and yet therein it appears perfectly at liberty to exert its own voluntary motions, and can either retire into the common receptacle, or push itself out from thence and expand its curious members, with- out interfering with or disturbing its companions.

" They dwell together from the number often to fifteen, (seldom ex- ceeding the latter or falling short of the former number,) in a filmy kind of mucilaginous or gelatinous case, which out of the water has no determined form, appearing like a lump of slime, but when expand- ed therein, resembles nearly the figure of a bell with the mouth up- wards ; and is usually about the length of half an inch, and one quar-

Alcyonella. Z. ASCIDIOIDA. 317

ter of an inch in breadth or diameter. This case being very trans • parent, all the motions of its inhabitants may be discerned through it distinctly. It seems divided internally into several apartments, or rather to contain several smaller Sacculi, each of which encloses one of these animals. The openings at the tops of these Sacculi are but just sufficient to admit the creature's head, and a very small part of its body, to be thrust out beyond them, the rest remaining always in the case. The animal can, however, when it pleases, draw itself en- tirely down within the case, which is an asylum to secure it from its enemies, (for it is not unlikely many of the larger aquatic insects prey upon it,) and a safe and agreeable retirement wherein to perform the functions of digestion, sleep, and the other necessary calls of nature. This case it can, I say, retire into at pleasure ; and it never fails to do so when any sudden motion of the water or of the vessel it is in dis- turbs it : as also when it has seized with its arms any of the minute insects which serve for its food.

" The arms are set round the head to the number of forty, having each the figure of a long^ one of whose hooked ends is fastened to the head ; and all together when expanded compose a figure somewhat of a horse-shoe shape, convex on the side next the body, but gradually opening and turning outwards, so as to leave a considerable area within the outer extremities of the arras. And when thus extended, by giving them a vibrating motion, the creature can produce a current in the water, which brings the ani- malcules, or whatever other minute bodies are not beyond the sphere of its action, with great velocity to its mouth, whose situation is between the arms : where they are taken in if liked, or else by a contrary current, which the creature can excite, they are carried away again : whilst at the same time other minute animalcules or substan- ces, that by lying^without-side the inclosure made by the arms are less subject to the force of the stream, are frequently seized by them : for their sense of feeling is so exquisite, that on being touched ever so slightly by any such little body, it is caught immediately and con- veyed to the mouth. However, one may observe the creature is sometimes disappointed in its acquisition, for after drawing down one of the arms suddenly inwards towards the mouth, it may be perceiv- ed slowly extending itself again without the creature's retiring into its case ; which it fails not to do on meeting with anything worth

the while.

" The food is conveyed immediately from the mouth cr opening between the arms, through a very narrow neck, into a passage seem- ingly correspondent to the oesophagus in land animals ; down which

318 Z. ASCIDIOIDA: Aixyonella.

it ^passes to the stomach, where it remains for some time, and then is voided upwards in small round pellets, (which at first I imagined to be its eg-g-s,) through the gut, whose exit is near a neck, where it was first taken in.

" The body of this animal consists of three parts or divisions, in the uppermost whereof all the aforementioned intestines are con- tained, though they are not to be distinguished when the creature is hungry ; but after it has eaten they become distended and opake, and may very plainly be discovered. The other two divisions (the lower- most of which I take to be fixed to the bell or outward case,) seem of no other service than to give the creature power of contraction and extension.

" The arms seem not able like those of the common Polype to contract or shorten themselves ; but instead thereof, when the ani- mal retires into his case, they are brought together in a close and cu- rious order, so as easily to be drawn in. Their general figure when expanded is that of a cup, whose base and top are of an horse-shoe form ; but they present sometimes a very diff'erent appearance, by separating into four parts, and ranging themselves in such sort as to represent four separate plumes of feathers.

" I could never discover any eyes they have, and yet find some reason to believe they see : for on being set in the light of the sun, or a candle, or brought out of the dark into daylight, though con- tracted before and I'etired into the bell, (as indeed they generally are when in the dark,) they constantly extend their arms for prey, and shew evident signs of being pleased.

" Besides the particular and separate motion each of these crea- tures is able to exert within its own case and independent of the rest, the M'hole colony has together a power of altering the position, or even of removing from one place to another the bell or common ha- bitation of them all. Hence this bell is seen sometimes standing perfectly upright, sometimes bending the upper part downwards.

" It has been mentioned already, that between ten and fifteen of these animals dwell together, as it were a little community, in one bell-like case or common habitation : but their number increasing, this bell may be observed to split gradually, beginning from about the middle of the upper or anterior extremity, and proceeding downwards towards the bottom, till they separate at last entirely, and form two complete colonies, independent of each other ; one of which some- times removes itself to another part of the vessel. The manner how the single animals propagate I have not been able to discover, though

Alcyonei.la. Z. ASCIDIOIDA. 319

there is some reason to conjecture it may be by the means of eggs ; as small opake bodies of a constant and determinate figure are some- times seen lying in their bells : and unless they are eggs I know not what to make of them. Their shape is nearly that of a weaver's shuttle, being composed of two circular arcs, whose concave parts are towards each other. The breadth is about two-thirds of the length, and in the middle of each a circular spot appears more opake than the rest, which possibly may be the embryo. But as I never saw any of them come to perfection, I can make no farther judgment of them than what their situation and form suggests.

" The bells or colonies of these animals are to be found adherine: to the large leaves of duckweed and other aquatic plants ; and may easiest be discovered by letting a quantity of water with duckweed in it stand quietly for three or four hours in glass vessels, in some window or other place where a strong light comes ; for then, if any are about the duckweed, they will be found on careful inspection ex- tending themselves out of their cases, spreading their plumes, and making an elegant appearance.

" They are extremely tender, and require no little care to preserve them : their most general disorder is a kind of slime or mouldiness, which will sometimes envelope them in such a manner as to prove mortal. The best way of curing this is by gently pouring a large quantity of water (perhaps two or three quarts) into the vessel where they are kept, and letting it run off slowly : by which means the sliminess will gradually be loosened and carried away with the water.

" As to food, if fresh water be given them daily they will find sufficient for themselves ; and it is dangerous to try any other way of feeding them, for the smallest worms or other visible insects one can think of giving them will tear their delicate frame in pieces."

Pallas has added nothing to the history of this polype, which he

had, nevertheless, personally examined. Bosc having collected, in

ponds near Paris, a polypidom of a massive character, apparently un- known, sent it to Bruguiere, who described it as a new species of Alcyonium. The same production having come under Lamarck's inspection, he formed oi it the genus Alcyonella, which was imme- diately adopted by all naturalists, for Bruguiere's description of the polypes (the accuracy of which was vouched for by Lamouroux!) difi'e- red in so many obvious particulars from Trembley's, that no one could suspect their identity, the more especially as the figures of the poly- pidoms were equally dissimilar. Bosc's polypidom was therefore ca- talogued in o\ir systems as an Alcyonella, and Ti'embley's as a spe-

320 Z. ASCIDIOIDA. Alcyonella.

cies of Plumatella, Thus matters stood when Raspail was led, in 1826 and 1827, to examine the subject, and the result of his inge- nious labours has been very curious, though some of his conclusions, notwithstanding the boldness of their enunciation, seem to me un- proved, and one of them, which identifies the Cristatella with the Alcyonella, has already been shewn to be erroneous. He has, how- ever, demonstrated very satisfactorily the entire sameness of the Po- lypes a panaches of Trembley, the Bell-flower animal of Baker, and the Alcyonella of Lamarck, — the variations in the polypidom, which had deceived all others, being produced by age, or by external and for- tuitous circumstances, as for example by peculiarities in its site : when this is the floating leaves of Lemnae, or the upper or under side of a stone, the developement is difl'used, or lobed, or arborescent, or creep- ing, or massive and spongy, according as the polypidom has free- dom to spread, or is restrained by its position, or is influenced by the mere gravitation of one part against another. I can find, however, in the beautiful series of figures which illustrate his Memoir, none to make me assent to Raspail's opinion that all the Plumatellae are cei'- tainly mere variations of this zoophyte : at present the facts appear rather of an opposite tendency ; — while, on the contrary, subsequent observations have shewn that he is right in considering as embryo Alcyonellse the Leucophra heteroclita and Trichoda floccus of Mul- ler, as well perhaps as the Difl3ugia protaeiformis of Leclerc, although Ehrenberg declares against this conclusion.

Raspail's description of the zoophyte is admirable, and is rendered peculiarly interesting from the generalizations in physiology which the author ever and anon boldly hazards on certainly a very narrow basis ; and the curious experiments detailed in it. He has fully re- cognized the merits of Trembley, and has confirmed his accuracy in most particulars ; he has explained the cause which led Trembley erroneously to ascribe a retractor muscle to the body, the appearance being the result of a fold or plait in the tunic in certains positions of the body ; he ascertained the position of the anus ; gave a complete view of the tentacular apparatus, and an inimitable anatomy of the ova, which we shall transcribe at least in part. The ova, he says, are in ge- neral one-third of a millimetre in their longest diameter. On each of the two parallel faces we distinguish a shield, a little convex, and of the same shape as the e^^ itself, surounded with a rim of the same co- lour and consistence. (Fig. 49, a.) In drying, these two faces approxi- mate and become concave, while the rim remains unaltered. A sec- tion perpendicular to the two faces shews that the rim has no com- munication with the shield, (Fig. 49, b.) ; that it is distended with a eel-

Alcyonella.

Z. ASCIDIOIDA. Fig. 49.

321

/.

lular tissue of the same substance as the parietes ; and that the shield incloses, under a shell of the same nature as the rim, a glutinous cel- lular tissue, the cells of which are filled with transparent, apparently amylaceous, g-rauules, spread in my«ads over the object-glass when the perisperm is torn. The most minute observation has been employed without success in fiiyjing any indication of an organ analogous to the embryo.

By a section parallel to the two faces the difference which exists between the structure of the rim and shield is made apparent. Of the former the coat, deprived of the tissue which it contains, is seen to be transparent and divided into j^.

cellules arranged in rays which point towards the centre of the organ ; while the resinous and woody thickness of the shield presents a great number of small globular yellowish cells dispos- ed in quincunx. (Fig. 30.) This ar- rangement becomes still more appa- rent on boihng the ovum in alcohol, Avhich however, no otherwise than ether, does not seem to discolour it much. Its brown colour is not owing to the presence of iron, for a long soak- ing of the eggs in prussiate of potass sharpened with sulphuric acid has not communicated the slightest tint of blue to their surface, even when they have been bruised previous to the maceration. Alcohol changes to a golden yellow the original brown colour of the shield. Iodine

322

Z. ASCIDIOIDA.

Plumatella.

does not colour at all, if not a yellow, the granules of the perisperm which their appearance suggested to be amylaceous, but alcohol sepa- rates from them a fatty substance, for, in spontaneous evaporation, this menstruum deposits on the object-glass a white layer over which water glides without raising any thing from it.

On examining by refraction one of the eggs with a magnifier of 100 diameters, very often another transparent narrow margin becomes visible, which overlaps all the circumference and indicates an external envelope of extraordinary delicacy. On one side of this there is to be distinguished an evident trace of the old adhesion of the egg to the walls of the tubes which enclosed them, — a point which may be call- ed the hilum. Very often, however, this delicate tunic may be sought for in vain on other eggs.

43. Plumatella, * Bosc. Character- Polypidom fixed, membranaceous, confervoid, slender, tubular, irregularly branched ; the polypes issuing from the apices of the branches. — Polypes ascidian, croicned with a single series of ciliated tentacula.

it- 1. P. REPENS, " stem adhering ; tentacula disposed in a cres- cent." Rev. Dr Fleming.

Fig. 51.

Tubipora repens, Lin. Syst. edit. 10, 790 Tubularia repens, Mull.

Verm. i. ii. 16. Zool. Dan. prod. 254. Bosc, Vers, iii. 93 Tub.

reptans, Turt. Gmel. iv. 669. Plumatella repens, Lam. Anim. s.

Vert. ii. 108. 2de edit. ii. 123. Flem. Brit. Anim. 322. Stark, Elem.

ii,441 Naisa repens, Coral. 98 La Plumatella rampante,5Zamr.

Actinolog. 490. f-

* The diminitive oiplumata — plumed.

f To this synonymy it may be useful to add the following, communicated to me along with a dried specimen of the polypidom, by J. Hogg, Esq. " A small piece of it is figured in Schaff. Armpolyp. tab. i. fig. 1, 2, published in 1754. The next representation of it is in tab. 19, fig. 1-5, in the Bulletin Philomatique

Plumatei.la. Z. ASCIDIOIDA. 323

Hab. " On the under side of stones. Lochmill-loch, Fife," Flem- ing. " Not unfrequent in a rivulet of beautifully clear water, at Nor- ton, in the county of Durham," John Hogg, Esq.

" Stem extending; several inches, irregularly branched, slightly en- larging towards the aperture, dilatalde ; tentacular margin divided into two lobes, tentacula ciliated in opposite directions. Besides a gullet, stomach, and gut, there is a distinct rectum, terminating in a tubular orifice seated externally to the tentacular margin, out of which I have witnessed the remains of the food swallowed but a short time before forcibly ejected." Fleming.

*2. V. g'E.IjKTI'hos A, ^'^ free, branched ; tentacula circularly dis- posed."— Rev. Dr Fleming.

Tubiilaria gelatinosa, Pall. Elencli. 8.3 Plumatella gelatiiiosa, Flem.

Br. Anim. 553.

Hab. "■ Found along with the preceding," Fleming.

" Height about two inches, tufted, shrubby ; stem dichotomously branched, scarcely enlarging at the extremity ; polypi with a bell- shaped disk, the tentacula regularly disposed, and appearing as if webbed at the base ; mouth with a valve." Fleming.

3. P. SULTANA, irregularly branched ; tentacula campanulate. J. G. Dalyell.

Tubularia sultana, Blumenh. Man. 272. pi. 1. fig. 9. Bosc, Vers, ill. 93.

Hab. Fresh water. Near Foulden, Berwickshire, Dalyell.

Polypidom irregularly branched, about an inch in height, earthy brown, roughish and opaque, the tubes short, cylindrical and unjoint- ed ; polypes entirely retractile, with about 20 slender white tentacu- la, assuming when expanded a regular campanulate figure. Blumen- bach says they are ciliated at the base.

As I have already stated, Raspail considers the Plumatellae (with the exception of P. sultana, which he does not mention,) to be mere- ly states of the Alcyonella,* — an opinion which future inquiries may shew to be true, but at present there are some difficulties in the way of its adoption. Pallas had examined both the Polypes-a-panache of

(not Bull. des. Sciences Nat.) p. 157, no. 81, an 12 (de la Republique)=1804, belonging to an extract from a memoir by Vaucher on the fresh-water Tubulariae : there fig. 1. much resembles the polypary in its natural state, but the animal mag- nified is not near so like as that figured in the former work : however neither plates do justice to the polj-pes."

" Mr J. E. Gray, in 1832, says, " It is probable that the Plumatellae may be only the young of the Alcyonellae." Syn. of Brit. Mus. p. 75.

324 Z. ASCIDIOIDA. Plumatella.

Trembley, and his Tiibnlaria gelatinosa, in a living state, and he as- serts that the latter — a Plumatella— differs from the former — an Al- cyonella — not solely in habit,* but in having fewer, shorter, and more recurved tentacula. " Interaneis quoque" he adds, " a prsecedenti differt et distinctissima est hcec species, quae interdum in iisilem cum praecedenti (semper rariore, adeoque, ut videtur, minus prolifica) re- peritur aquis." Muller's description of Plumatella repens certainly affords nothing in opposition to Raspail's theory, but on the contrary may be deemed favourable to it, since he tells us that it is intermedi- ate between the very species which Pallas considered so widely diffe- rent, possessing many of the characters of both, and differing princi- pally in the appearance of the polypidom. Lamarck* perceived the affinity of the genera, which he nevertheless kept separate, resting the distinction on the massive and ramous forms of the polypidoms. Baer, apparently speaking from personal examination of the produc- tions in question, has expressed his conviction of the perfect distinctness of Alcyonella and Plumatella, and this subsequent to his knowledge of Raspail's Memoir : and Milne-Edwards has still more recently shown that this essay had at least not conveyed perfect conviction to his mind, otherwise he would scarce have expressed himself in this man- ner : " II nous parait en effet probable que ces Polypes, observes a des periodes diverses de leur developpement, ont ete pris pour des animaux differens et decrits sous des noms particuliers. Mais il se- rait possible aussi que les formes transitoires de I'Alcyonelle decrites par M. Raspail se rencontrassent d'une maniere permanente chez d'autres Polypes, et par consequent, on ne pent encore rayer des ca- talogues zoologiques la longe suite d'especes mentionnees ci-dessus." Lam. Anim. s. Vert. 2de edit. ii. 116. — Under these circumstances I have deemed it the best course to keep the genera separate, as least likely to perplex the student.

Of the P. Sultana little is known. 1 have seen a living specimen in the possession of Sir John G. Dalyell, but had no opportunity of making an examination of it. Naturalists wait with some impatience the publication of a work from this ingenious observer, on which, it is understood, he has been long engaged, and which will disappoint ex- pectation if it does not disclose many novel facts, and illustrate many present obscurities, and give additional respect and permanence to his name and reputation as a naturalist.

• " Habit is a general agreement in growth and appearance." f.imifeus.

ADDITIONAL NOTES.

1. The Nature vf Sponges. Page 29 ^

1 may fortify my opinion of the vegetable nature of these productions by the following quotation from the " Elements of Physiology" by Muller, the cele- brated professor of anatomy in the university of Berlin " If, therefore, it is

still a matter of doubt whether certain simple organized beings, such as the sponges and several so called alcyonia, are animal or vegetable, the absence of all voluntary motion in these bodies, whether of the whole or of individual parts of it, must determine the question, and they must more properly be numbered among the vegetable marine structures. It may certainly be said that the embryo of sponges, as Dr Grant has shown, like the embryo of polypes and corals, moves by means of cilia ; but the distinctive marks between the embryo of sponges and marine infusoria are by no means certain, and similar motions have been many times observed in the embryo of true vegetables, — of the alga, for example." p. 42. Lond. 1837.

Mr J. Hogg, hi a letter dated June 25, states that the green colour of the fresh water sponge (Spongilla fluviatilis) depends upon the action of light, — as he has proved by experiments which shewed that pale coloured specimens became green when they were exposed, for a few days, to the light and full rays of the sun ; while on the contrary green specimens were blanched by being made to grow in darkness or shade. Hence Mr H. infers the vegetability of this sponge ; but he still leans to the opinion that the sea sponges are animals.

Dujardin, again, is a new advocate for the animality of all sponges ! " M. Dujardin having repeated his observations on spongillse or fresh water sponges, as well as others on marine sponges, thinks he has proved, that these ambiguous beings are positively groups of animals, capable of contraction and extension. If a piece be detached from a living sponge, and submitted to a microscope, it will be seen to groupe itself into irregularly rounded masses, and change the form of its edges incessantly : isolated portions, detached from the general mass, move slowly in the liquid, and creep along by means of their alternate contrac- tion and expansion." Athenaeum, June 16, 1838, p. 430 I may remark on

these experiments, that locomotion is no proof of animaUty. Several algce are locomotive.

2- The asexual character of Zoophytes. Page 46. This is contrary to the opinion of Professor Wagner. He says that double- ness of sex appears to be an invariable condition of all animals ; and when the sexes are not separate individuals, there always exists a hermaphroditical organ- ZHtion. He has discovered masculine organs in the Actinice. " I found, last Autumn," he says, " in the isle of Heligoland, upon the Actinia holsatica and rufa

326 NOTES.

testicles formed by numerous canals twisted around one another : tbey were much developed and placed along-side the ovaries, which they equalled in num- ber." Their real nature was ascertained by the detection of spermatic animal- cules in them ; and these were also found in the Act. effceta Ann. des Sc.

Nat. tom. viii. p. 283, &c.

3. Structure of the Hydra. Page 99.

Augustus Josephus Corda has recently published a memoir on the anatomy of Hydra fusca, where he shews that this is greatly more complicated and curious than has hitherto been imagined. According to Corda each tentaculum forms a slender membranaceous tube filled with an albuminous nearly fluid substance intermixed with some oleaginous particles -. this substance swells out, at certain definite places, into denser wart-like nodules which are arranged in a spiral line. These are the tubercles noticed by all observers, but no one had hitherto develop- ed their structure. Corda says that each nodule is furnished with several spini- gerous vesicles used as organs of touch, and mth a very singularly constructed organ for catching the prey. The organ of touch consists of a fine sac enclosing another mth thicker parietes, and within this there is a small cavity. From the point where the two sacs coalesce above, there projects a long cilium or capil- lary spine which is non-retractile, and apparently immoveable. Surrounded by these cUia, and in the centre of the nodide, is placed the captor organ, called the hasta. This consists of an obovate transparent sac, immersed in the nodule, with a small aperture even with the surface. At the bottom of the sac, and within it, there is a saucer-like vesicle, on whose upper depressed surface is seat- ed a solid ovate corpuscle that gives origin to, or terminates in, a calcareous sharp sagitta or arrow, that can be pushed out at pleasure, or withdrawn till its point is brought within the sac When the Hydra wishes to seize an animal, the sagittoE are protruded, by which means the surface of the tentacula are roughen- ed, and the prey more easily retained : and Corda believes that a poison is at the same time injected, which will explain the remarkable fact of the almost instant death of the prey.

The nodules of the tentacula are connected together by means of four muscu- lar fibres or bands which run up forming lozenge-shaped spaces by their inter- sections. These are the extensor muscles of the tentaculum. They are again joined together by transverse fibres, which Corda believes to be adductor mus- cles, and to have also the power of shortening the tentacula. Corda states that there is no communication between the tube of the tentaculum and the ca\'ity of the body.

The lip of the mouth is armed with hastce and cilia similar to those of the tentacula, but the rest of the body is destitute of them.

The skin consists of two strata, the exterior largely cellular, the inner with cells of a much smaller size. In thje latter the gemmules lie. Under it there is a layer consisting of densely aggregated cells, filled and coloured with minute granules. This layer Corda regards as muscular ; and within it there is another layer which, from its texture and position, he says may be called the villous coat. From the inner surface of this, numerous villi project into the stomachal cavity, collected into masses which are divided from each other by passages destitute of villi. Each of the villi is in the form of a cylindro-conical pellucid vesicle filled with the nutrient matter ; and most of them are perforated on the tip while

3

NOTES. 327

others arc closed, though equally filled with nourishment. The digestion of animal matter is very rapid ; the pachydermatous larva of an insect being ren- dered irrecognisablc in four minutes. Vegetable matter is an inappropriate food, and seemingly indigestible. See Ann. dcs Sciences Nat Part. Zool. tome viii. p. 363, &c — It were well that this anatomy of Corda was confirmed, for the fallacy of the microscope is almost proverbial, and powers of very high in- tensity must have been used in this demonstration.

4. The nature of the Cells of the Escharidce- Page 238.

" If the stony cells of the Escharidae were formed by the exudation of a cal- careous matter which moulded itself on the surface of the secreting membrane, it is evident that the first layer thus formed must be the external one, and that the addition of new quantities of this earthy matter could only augment the thickness of the parietes of the cell, and modify the disposition of its interior cavity, with- out at all changing the exterior configuration of the first formed layer ; for here the solid cell completely envelopes the animal, and is not overlapped by the se- creting organ, as in the Mollusca gasteropoda, whose shell changes its form with age, because the deposit of new matter, taking place on the border of the part already consolidated, continually lengthens it, and is moulded on the soft parts whose configuration is liable to change.

" To throw some light on the mode of formation and on the nature of the cells of the Eschares, it became consequently interesting to examine these cells at diflferent ages, and to see if their exterior form changed or remained always the same. This study, indispensable for the anatomical and physiological history of these little beings, may also lead to a knowledge useful to zoology and to geology J for the determination of the species, recent and fossil, rests principally on the characters furnished by these cells ; and we are still ignorant whether or not they can be modified in the progress of age.

" This examination can be made more easily than one might at first ima- gine ; for neither the observation of the same individual, at different stages of its developement, nor the collection of a series of specimens so as to repre- sent all the phases through which these little creatures pass successively, is re- quired. Indeed, since these polypes spring from each other, and do not separate from their parents, each polypidom must present a long series of generations en- chained to each other, and in each of these series, the relative age of living in- dividuals must be indicated by the place which they occupy. To resolve the question which we have put, it is sufficient therefore to study comparatively the cells situated near the base of the polypidom, in its middle, in its young branches, and towards the extremity of the latter ; for we are certain that it is not only in this last place that living polypes are found, as some authors affirm, but that they exist over almost the entire extent of the polypidom.

" After examining in this manner, with a sufficient magnifying power, the cells of the Eschara cervicornis, I am quite convinced that the mode of develope- ment of these stony cells is not that which is usually admitted.

" Indeed, I have seen that not only does the general conformation of the cells change with age, but also that these changes operate in a great measure on the exterior surface, — that is to say, on that side of their parietes, which, in the hypothesis of their formation by layers, must exist from the first, and once con- solidated, ought to change no more, unless from exterior and accidental frictions.

328 '' NOTES.

" In the young cells, whose partitions, although thin, have already acquired a stony consistence, the exterior surface is quite convex, and the margin of their aper- tures jut out so that they are easily distinguished ; but by the progress of age their appearance changes ; their free surface rises so as to efface the deep de- pressions which marked originally their respective limits, and to raise to the le- vel of the surface the border of the openings. The result of this is that the cells cease to be distinct, or even distinguishable without, and that the poly- pidom seems to be formed of a stony continuous mass, in the substance of which are excavated certain holes slightly widened interiorly, and disposed in quincunx.

"But differences of this nature cannot be formed by the simple juxtaposition of new calcareous layers under those primitively formed ; for the soft parts of the animal, the only ones which can be the seat of a secretion of this calcareous matter, do not extend over the surface which is thus modified ; and the position of the cells thus immersed in the apparently common mass of the polypidom is often such that we cannot attribute their change of form to any operation or friction of foreign bodies.

" It appears evident to us that these facts indicate the presence of life in the substance which composes the parietes of these cells, and can only be explain- ed by the existence of a nutritive movement ; like to that which, in the confi- guration of bones, effects analogous modifications.

" To know better the nature of these cells, I submitted to the action of ni- trous acid diluted with water, a part of a polypidom recently taken from the sea. A brisk effervescence was visible immediately, and in some minutes the cells became flexible, and separated from one another. Before treating them thus, no distinct membrane was seen on the internal wall of these cells ; and when the nitrous acid had destroyed all the calcareous carbonate on which their ri- gidity depended, these same parietes still existed and had not changed their form much : only they were formed now of a soft and thick membrane con- stituting a bag, in the interior of which we perceived the digestive apparatus of the polype. The opening of this bag was no longer truncated, as it appeared when the texture of the membrane was thickened by the stony deposit from which we had just freed it, but the membrane was continued uninterruptedly with the tentacular sheath.

*' We see then that in the Eschares, the cell in which it is said the polype retires as into a shell, is a component part of the animal itself, in which it conceals itself, if we may use the comparison, as the hedgehog enters into the thorny skin of his back. It is not a calcareous crust which is moulded on the surface of its body, but a portion of the general tegumental membrane, — of the skin of the polype, — which, by a molecular deposit of earthy matter in the meshes of its tissue, ossifies as the cartilages of superior animals ossify, without ceasing to be the seat of a nutritive movement.

" We see also that that which is considered generally, as being the body of these polypes, constitutes in reality only a small portion of it, and consists of little but the digestive, and probably breathing organs, of these little animals.

" The tegumental bag, freed from its carbonate of lime, seems to me formed of a toraentose membrane covered, particularly \vithout, with a multitude of cy- lindrical filaments, disposed perpendicularly to the surface, and pressed close to one another. It is in the spaces left between these fibres that the calcareous matter appears to be principally deposited, for if we examine, with the micro-

NOTES. 329

scope, a transverse cut of the polypidom in its natural state, we distinguish in it an analogous conformation, the external wall of the cells being not composed of layers, but rather of cylinders or irregular prisms placed perpendicularly to its surface.

" As to the operculum, which serves to shut the entrance of the tegumental cell of the Eschara, when the animal is wholly concealed in it, it is but a labial fold of that which we may call the skin of the polype, and of which the pro- jecting margin has acquired a horny consistence, whilst that portion continuous with the general envelope, preserves sufficient softness to remain flexible, and to obey the action of the muscles whose tendons are inserted in its thickness.

" The changes which we have indicated above in the external formation of the cells of the Eschares are not the only ones effected by the progress of age in the stony integuments of these zoophytes. The form of their opening is modi- dified considerably, as may be seen by the figures which accompany this memoir -. the sinus or emargination situated under the operculum disappears by degrees, and their interior ca\Tty becomes filled up so as not to occupy more than about the quarter of their original diameter. This thickening changes even a little the genend appearance of the polypidom ; for as it is more considerable in the cells situated farthest from the extremities of the branches, it results that these, at first almost flat, become more and more cylindrical. Lastly, it is not without surprise that we have seen these same cells when they are arrived at ex- treme old age, lose altogether the opening from which the polype extended its tentacula. In fact, the margins of this opening swelling more and more out- wardly come at last to touch and to close, so that no trace of its existence is left : but the cell, now a shut cavity, still exists towards the axis of the polypi- dom.

" Thus, then, the last external mark of the individual existence of these col- lected polj-pes, disappears before that life is extinct in the interior, and the most remarkable character of the polypidom is lost without hope of recovery.

" Reflecting on the fact we have just noticed, we are naturally led to ask how the nourishment necessary for the support of the secretions on which the pro- gress of consolidation depends, can continue when the cell containing the di- gestive apparatus of the animal is shut up in this manner. Is it from its neigh- bours that it receives its nutritive matters, or can it continue to absorb them direct- ly from without through these stony integuments? The nature of this solid shell seems at first sight to oppose great obstacles to this imbibition, particularly to that which would take place by the free surface of the polypidom, but an ex- periment which is, so to speak, the counterpart of that which has been already detailed, shov/s that it is otherwise.

" On boilinga fragment of the solid polypidom ofan Eschara in a solution of caus- tic potash, I have extracted the major part of the substances which compose the organized part of its tissue, and I have then seen that the appearance of the polypidom is considerably changed. The external parietes of the cells had become of an almost spongy texture, and its surface, instead of being simply granular, presented a great number of very distinct pores, which were before concealed by the soft parts with which they were filled.

" We may understand, then, that the organized tissue of the old polypes finding itself without covering in different points of the external surface of the cells.

330 NOTES.

the absorption may continue to be effected directly from wnthout, although the opening by which the nutritive matters penetrate usually into the digestive cavity, is obstructed and obliterated." — Ann. des Sciences Nat. Part. Zool.,Vol. i. p. 25-31.

" And novv^, shoidd it be asked, granting all this to be true, to what end has so much labour been bestowed in the demonstration ? I can only answer, that as to me these disquisitions have opened new scenes of wonder and astonishment, in contemplating how variously, how extensively life is distributed through the universe of things : so it is possible, that the facts here related, and these in- stances of nature animated in a part hitherto unsuspected, may excite the like pleasing ideas in others ; and in minds more capacious and penetrating, lead to farther discoveries, farther proofs (should such be wanting,) that One infinitely wise, good, all-powerful Being has made, and still upholds, the whole of what is good and perfect ; and hence we may learn, that, if creatures of so low an order in the great scale of nature are endued with faculties that enable them to fill up their sphere of action with such propriety ; we likewise, who are advan- ced so many gradations above them, owe to ourselves, and to Him who made us and all things, a constant application to acquire that degree of rectitude and perfection, to which we also are endued with faculties of attaining." — Ellis.

EXPLANATION OF THE PLATES.

PLATE I. Fig. 1. Hydra vulgaris, var. b, natural size : specimens from Yet-

holm Loch, Roxburghshire. Fig. 2. H. vulgaris, var. a, nat. size and

magnified. PLATE II. Fig. I. Coryne squamata., nat. size and magnified. Fig. 2. C.

squamata, loaded with reproductive gemmules. Fig. 3. The same magni- fied. Fig. 4. Variety of C. squamata, Fig. 5. The same magnified. PLATE III. Fig. 1 Tubularia indivisa, nat. size. Fig. 2. Head of the same

magnified. Fig. 3. Tub. Larynx, nat. size. PLATE IV. Fig. I. Hermia glandulosa, var. nat. size. Fig. 2. The same

magnified. Fig. 3. Tubularia Larynx, var. nat. size. Fig. 4. The same

magnified. Fig. 5. Gemmules, magnified. PLATE V. Fig. 1. Tubularia ramea, nat. size. Fig. 2. A portion of the same

magnified. Fig. 3. Tubularia Larynx, var. nat. size. Fig. 4. A portion

of the same magnified. PLATE VL Fig. 1. Thoa halecina, nat. size. Fig. 2. A small variety of the

same. Fig. 3. A piece of the stalk magnified. Fig. 4. A piece of the poly-

pidom magnified. PLATE VII. Fig. 1, 2. Thoa Beanii, nat. size and magnified. Fig. 3, 4. Thoa

muricata, from a specimen communicated by Mr Bean. PLATE VIII. Fig. I. Sertularia polyzonias. Fig. 2. A variety of the same.

Fig. 3. The same magnified. Fig 4, 5. Sertularia rugosa. Fig. 6. A creep- ing var. of Sert. rugosa, magnified. PLATE IX. Fig. I. Sertularia rosacea, of the nat. size. Fig. 2. A portion

magnified. Fig. 3, 4. Sertularia pumila. Fig, 3, 6. Sertularia pinnata. PLATE X. Fig. 1, 1." Sertularia abietina, of the nat. size and magnified.

Fig. 2. Sertularia tamarisca. Fig. 3. A portion magnified. Fig. 4. The

ovarian vesicle, copied from Ellis. PLATE XI. Fig. 1, L* Sertularia filicula, nat. size and magnified. Fig. 2,2.*

Sert. operculata. Fig. 3, 3.* Sert. argentea, var. in a young state. PLATE XII. Fig. 1. Sertularia argentea. Fig. 2. The same in its young state.

Fig. 3, 4. Portions of two diiferent specimens of the same magnified, to

shew the variations of the cells. PLATE XIII. Fig. 1, 2. Sertularia cupressina, from a specimen presented to

me by J. V. Thompson, Esq. PLATE XIV. Fig. 1, 2. Thuiaria thuja, nat. size and magnified. PLATE XV. Fig. 1, 2. Thuiaria thuja, in its primary state. Fig. 3, 4. Th. ar.

ticulata, from a specimen in the collection of Mr Bean. PLATE XVI. Antennularia antennina. Fig. 2. represents the branched variety.

332 EXPLANATION OF THE PLATES.

PLATE XVII. Fig. 1, 2. Plumulaiia falcata. Fig. 3. The vesicle magnified.

Fig. 4, 5. PI. pinnata, of the natural size and magnified. PLATE XVIII. Fig. 1, 2. Plumulariapennatula, from a specimen presented to

me by J. E. Gray, Esq. Fig. 3, 4, 5. PL setacea, 4, is from specimens

sent from Cork by Mr Thompson. PLATE XIX. Fig. i, 2, 3, Plumularia cristata. Fig. 4, 5. PI. myriophyllum,

from a Devonshire specimen given to me by Dr Coldstream. PLATE XX. Fig. I. A variety of Plumularia cristata. Fig. 2, 3. Plum, fru-

tescens : specimen from Mr Bean. PLATE XXI. Fig. 1,2. Laomedea geniculata. Fig. 3, 4. Laomedea gela-

tinosa. PLATE XXII. Fig. 1, 2. Laomedea dichotoma, nat. size and magnified.

Fig. 3, 4. Campanularia verticillata. PLATE XXIII. Fig. 1. Laomedea gelatinosa, variety, from a specimen in the

collection of Dr Coldstream. Fig. 2. Campanularia? dumosa, variety.

Fig. 3. The same magnified. Fig. 4. C ? dumosa. Fig. 5. The same

magnified. PLATE XXIV. Fig. I, 2, 3, 4. Virgularia mirabilis, from specimens sent to

me by Dr Coldstream. Fig. 5, 6. The same, copied from Muller. PLATE XXV. Fig. I. Gorgonia verrucosa, reduced one half. Fig. 2- Gorg.

placomus, copied from Ellis. Fig. 3. Gorg. anceps, also copied from Ellis. PLATE XXVI. Alcyonium digitatum, nat. size, with its polypes fully ex- panded. PLATE XXVI.* Alcyonium digitatum. Fig. 1. The Polype as it appears

when fully extruded and seen through a magnifier. Fig. 2. The Polype

when about to develope itself, and about one-third protruded. Fig. 3. A

view of the oral disk after the animal has been killed by immersion in fresh

water, and the piece placed between two plates of glass. Fig. 4. A view

of the upper part of the body compressed between plates of glass. Fig. 5.

A view of a transverse section of the polypidom, highly magnified, shewing

the longitudinal canals cut across, and the ova in them. Fig. 6. A cell still

more highly magnified to shew the developement of the ova. Fig. 7. The

spicula. PLATE XXVII. Actinia gemmacea, natural size. PLATE XXVIII. Actinia Dianthus. PLATE XXIX. Fig. I. Vesiculaiia spinosa, a small and perfect specimen.

Fig. 2. Specimens of the same as they are found when cast on the shore.

Fig 3. A portion of the same magnified ; the cells have fallen oflf. Fig. 4.

A portion with the cells remaining : copied from Thompson. Fig. 3, G.

Valkeria imbricata. Fig. 7, 8, 9. Valkeria pustulosa. For the sjjecimens

which furnished these figures I am indebted to Mr Thompson. PLATE XXX. Fig. 1, 2. Crisia cornuta. Fig. 3, 4. Crisia eburnea. Fig. 5,

6. Cr. luxata. Fig. 7, 8. Anguinaria anguhia. Fig. 9, 10. Hippothoa

catenularia. PLATE XXXI. Fig. I, 2,3. Tubulipora patina. Fig 4, 3, 6. Tubulipora

serpens. Fig. 7, 8. Tubulipora Obelia. Fig. 9, 10, II. Discopora hispida.

Fig. 12, 1.3. Notamia loriculata. PLATE XXXII. Fig. 1,j2. Ccliepoiii pumicosa, nat. ^izc. Fig. 3. The same

4

EXPLANATION Or THE PLATES. 333

magnified. Fig. 4. Cellepora ramulosa, iiat. size. Fig. 5. A cross section of a branch enlarged. Fig. 6. Cellepora Skenei, nat. size. Fig. 7. The same magnifi«!d. Fig. 8. A transverse section.

PLATE XXXIII. Fig. 1. Cellepora cervicornis, nat. size. Fig. 2. Amagnificd view of old or mature cells. Fig. 3. The cells from near the edge of the divisions. Fig. 4, 5. Transverse sections of the branches.

PLATE XXXIV. Fig. 1, 2, 3. Lopralia coccinea, 1, nat. size; 2, a few of the cells magnified ; 3, the cells with their ovarian opercula. Fig. 4. Le- pralia variolosa. Fig. 5. Lep. trispinosa. Fig. 6. Lep. ciliata. Fig. 7. Lep. nitida. Fig, 8. Lep. immersa. Fig. 9. Flustra tuberculata. Fig. 10, II, 12. Membranipora pilosa. 10, nat. size; 11, cells of, magnified; 12, cells of varietj' y8.

PLATE XXXV. Fig 1 , 2. Flustra foliacea. Fig. 3, 4. Flustra truncata.

PLATE XXXVI. Fig. I, 2. Flustra carbasea. Fig. 3, 4. Fl. avicularis. Fig. 5, 6. Fl. Murrayana. Fig. 7, 8. Cellularia avicularia.

PLATE 'XXXVH. Fig. I, 2, 3. Flustra niembranacea, nat. size and magni- fied. Fig. 4. Flustra lineata. Fig. 5. Fl. carnosa. Fig. 6, 7. Farcimia salicornia.

PLATE XXXVIII. Fig. I, 2. Cellularia ciliata, nat. size and magnified. Fig. 3, 4. Cell, reptans. Fig. 5, 6. Cell, scruposa.

PLATE XXXIX. Acamarchis plumosa, of the natural size and magnified.

PLATE XL. Eschara foliacea, reduced one half, with portions magnified to shew the cells.

PLATE XLL Alcyonidium gelatinosum. Fig. 1 and 2, specimens of the na- tural size to shew the variations to which the species is subject in outward form. F'ig. 3. The polype removed. This figure was made in the year 1833 ; and is less accurate than that of Dr Farre's. Fig. 4, 5. Alcyonidium parasiticum.

PLATE XLIL Fig. I. Alcyonidium hirsutum, of the natural size ; and Fig. % a portion of the surface as seen through a magnifier. Fig. 3, 4. Alcy- onidium echinatum. Fig. 5. Cliona celata. Fig. 6. The spicula of the same.

PLATE XLIII. Cristatella mucedo, copied from Turpin. Fig. 1. The poly- pe at the period of its birth, magnified. Fig. 2. The same when fully de- veloped : a, the transparent margin ; b, the disk of the polypidom ; c, the holes whence the polypes protrude ; d, the neck of the polypes and anus ; e, the tentacular arms, with the mouth at their base ; f, the filaments which fringe the tentacula ; the arroics mark the direction of the currents of water. Fig. 3. The tentacular filaments very much magnified to show their cilia.

PLATE XLIV. Alcyonella stagnorum. Fig I. natural size and appearance. Fig. 2. A longitudinal section. Fig. 3. A portion of the surface magnified. Fig. 4. A transverse section. Fig. 5. A front view or the polype. Fig 6. A back view of the same : copied from Raspail.

INDEX TO THE WOOD-CUTS.

No. 3-2. 31. 34. 29. 49. 50.

7.

5. 33. 39. 41. 24. 18. 17. 30. 23. 27. 43.

2. 10. 21. 19. 25. 26. 12. 42. 11.

4. 38.

9. 28. 35. 36. 37. 42. 22. 51.

Actinia maciilata

mesembrj'anthemiim

-, young of,

viduata

Alcyonella, ovum of,

, ovum of,

Alcyonidium, ovum of. Alcyonium digitatum, section of, Anthea Tuedioe Bowerbankia densa

Campanularia dumosa

syringa

voliibilis

Caryopbyllia Smitbii. Cornularia rugosa

Crisia cbelata Flustra membranacea Fusus, tbe capsule of? Gorgonia, section of the stem of,

Flabellum

verrucosa, animal of,

, ova of,

Hermia glandulosa

Hydra coronata. Fig. c, d.

fusca

viridis

Lagenella (Bowerbankia) repens Laomedea gelatinosa, polype and cell Luceraaria auricula

tentacula and ova of.

campanulata

Lucia ? Fig. a, b. Pennatula pbosphorea Plumatella repens

Page

Coldstream. 218

G. J. 210

G. J. 227

G. J. 205

Raspail. .321

Raspail. 321

G. J. 51

G. J. 39

G. J. 222

Farre. 240

- - - Farre- 256

G. J. 181

- G. J. 155

- G. J. 154

The animal is after De la Beche. 206

G. J. 181

Cavolini. 187

G. J. 260

G. J. 34

G. J. 92

Ellis. 168

G. J. 161

Cavolini. 182

Do. 186

G. J. 109

Lister. 258

Baker. 93

G.J. 37

Farre. 235

Lister. 83

G. J. 193

G. J. 229

G. J. 230

G. J. 231

Lister. 258

G. J. 175

G. J. 322

336 INDEX TO THE WOOD-CUTS.

No. 8. Plunaularia Catharina - - -

16. , magnified

6. cristata, gemmae of,

48. Polypes a panache . _ _

46. Retepora eellulosa _ _ _ 40. Serialaria lendigera 1 3. Sertularia nigra - - - •

15. , magnified,

14. rosacea, cells and vesicles,

20. Tree, dicotyledonous, section of,

1. Tubularia ramea ....

3. Vesicularia imbricata, polype of, 45. View of one of those Scenes on the coast, into which the naturalist is led in his search after zoophytes.

47. Ditto. - - -

	Page
G.J.	79
G.J.	148
Coldstream.	48
Tremhley.	314
G. J	283
G.J.	249
G. J.	119
G.J.	129
G.J.	125
- EUis.	168
G.J.	1
Thompson.	35
■IX	274
^	300

INDEX.

AcAMAKCHis - Page 293

neritina - - 293

plumosa - - 294

Actinia - . 210

anemone . 211

anemonoides 223

Bellis . 212

carcbiiopados - 218

caryophyUus - 223

Cereu.i - 221

coccinca - 214

comtnon - 211

coraUina - - 211

coriacea - 214

crasskornis - 214

Dianthus - 216

effata . 214-218

equina . 210-214

fe/ina . . 214

gemmacea - 213

gland ulosa - - 213

hemispherica - 211

intestinalis - - 213

judaica . - 217

maculata - - 218

margarilifera - 211

mesembryanthemum 210

monile . . 214

parasite - - 218

pcduncuhta . - 212

pentapctala - . 216

plumosa - . 216

mfa . - 211 senilis . . 213-216

sulcata - - 221

triincata - - 214

Tuedice - . 222

verrucosa - . 213

viduata - - 211

ACTINIID^ - - 205

Aetea ariguina - . 266

Aglaophenia falcata - . 141

frutescens - I49

myriophr/llum . 148

pennatula - - 145

pinnata - ]4g

pluma - - 143

sctacea . . 147

Alcyonella	Page 311
stagnorum	0 311
ALCYONID^	174
Alcvonidium	300
diaphanum	301
echinatum	304
Jlavescens	301
gelatinosum	300
hirsutum	303
parasiticum	304
ALCYONIDUL^	300
Alcvonium	187
cydonium	191
digitatum	188
Jluviatile	311
gelatinosum	300
tohatum	- 188
parasiticuni	304
rubrum	190
Amathia leudigera	251
Anemonia ediilis	222
Anguinaria	266
anguina	266
spatulata	266
Antennularia	139
antennina	139
indioisa	140
ramosa	140
Anthea	220
Cereus	221
Tuedias	221
ASCIDIOIDA	76-237
ASTEROIDA	76-163
Berenicea coccinca	278
flava	280
hyalina	277
i7nmersa	280
nitida	278
trispinosa	280
ntriculata	279
BOWERBANKIA	255
densa	2.').5
repens	256
Campanulauia	154
dichotoma	150
dumosa	157

338

INDEX.

Campanularia

gelatinosa

geniculata

syringa

verticillata

volubilis Caryophyllia

cyathus

Smithii Cellaria angtiina

avicularia

hursaria

chelata

cUiata

cornuta

eburnea

LonchHis

loriculata

neritina

plumosa

repians

scruposa

ternala

thuia Cellepora

cervicornis

cUiata

coccinea

liyalina

laevis

iiitida

palmata

pumicosa

ramulosa

skenei

spinosa

verrucosa CELLEPORID^ Cellularia

anguina

avicularia

hursaria

chelata

ciliata

cornuta

eburnea

falcata

farciminoides

fastigiata

Hookeri

loriculata

neritina

plumosa

reptans

salicornia

scruposa Clytia rugosa

syringa

Cl.lONA

celata Clyt'iu uva

vertlcillula

Page 154	Conferva cancellata
152	Cornularia rugosa
152	CORYXE
155	glandulosa
156	7nulticornis
155	squamata
207	Crisia
207	avicularia
207	chelata
266	ciliata
192	cornuta
264	eburnea
261	flustroides
290	loriculata
260	luxata
262	plumosa
138	reptans
263	scruposa
293	ternata
. 294	CRISIAD^
291	Crist atella
291	campanulata
263	mirabilis
137	mucedo
273	paludosa
276	vagans
279	Cuscutaire cuscute
278	CVDONIUM
277	Mulleri
277	Cymodocea
278	comata
275	simplex
273
274	Discopora
274	hispida
273	trispinosa
273	Dynamena abietina
247	argentca
290	hursaria
266	cupressina
292	Dynamena Evansii
264	Jilicula
261	nigra
290	operculata
260	pinnata
262	pumila
260	rosacea
295	tamarisca
294
293	Eschara
263	ciliata
293	fascialis
294	Jistnlosa
291	foliacea
295	foliacea
291	pilosa
124	retiformis
156	securifrons
305	ESCHARIDiE
305	Encratea chelata
253	cornuta
156	loricatn

Page 250 192 109 112 110 109 260 292 261 290 260 262 287 264 262 294 291 291 263 247 308 311 308 308 311 308 253 191 - 191 158 158 158

270 270 280 131 134 264 135 127 132 128 132 127 126 124 130

279 298 295 283 297 281 298 285 248 261 261 261

INDEX.

339

1'ahci.mia	Page 295	HVDUA	Page 93
Jistitlosa	- 295	conjnaiia	98
salicoriiia	295	Dianthus	- 216
Filipora Hlograna	- 272	fusca	96
Fistiilaria mtiscoides	- 115	gcmviacea	213
ramosa	117	grisea	95
Flabelliim veneris	185	Httoralis	98
Flustra	283	Jutea	98
angustiloha	287	mesemhryanthemum	211
avicularis	286	oligactis	96
hulluta	273	ramosa	112
capitata	287	squamata	109
carbasea	- 285	verrucosa	97
caiiiosa	288	viridis	- 93
chartacea	284	viridissima	94
denlata	281	vulgaris	95
Ellisii	286	HYDRAID.E	91
foliacca	- 283	HYDROIDA	75-«l
?iiria	288
hispida	289	Isis entrochus	186
liiieata	288	Hippuris	185
membranacea	287
Murrayana	- 287	Lagcnella repens	- 256
papyracea	284	Laomedea	. 150
pilosa	- 281	dichotoma	- 150
setacea	286	gelatinosa	- 152
spinifera	288	geniculata	151
spongiosa	- 282	muricata	121
telacea	288	spinosa	- 250
tuberculata	289	Lepralia	277
truncata	- 285	ciliata	279
tuhiilosa	271	coccinea	278
unicornis	289	hyalina	277
Fungia turhinata	206	immersa	280
		nitida	277
Gemicellaria bursaria	264	trispinosa	- 280
loriculata	264	variolosa	- 278
GORGONIA	182	LIMNIADES	- 248
anceps	- 184	Lohularia conoidea	191
flabellum	184	digiiata	- 188
lepadifera	- 185	Loricaria curopea	- 264
placomus	183	Loricnla loricata	- 261
verrucosa	182	LUCERNARIA	228
viminalis	183	auricula	229
GOllGONIAD^	174	campanulata	- 231
		convolvulus	231
Halodactylus diapbanus	301	fascicularis	228
HELIANTHOIDA	76-195	octoradiala	229
Hermia	111	Lucia ?	257
glandulosa	111
HiPpOTHEA	- 265	MADREPHYLLIiEA	- 205
catenularia	265	Madkepora interstincta	209
Elliotce	- 265	musicalis	- 209
lanceolata	- 265	porpita	. 209
HVDRA	93	truncata	- 209
Bellis	- 212	verrucaria	267
hrunnea	95	Membranipora	280
campanuldtoi	311	pilosa	280
capUala	no	spongiosa	. 282
Ccreus	221	Mclridititn pluinosum	2J6
coronata	257	iNIillcpora cellulosa ., .	297

340

INDEX.

Millepora cervicontis Page	276	Salicornaria Jistulosa	Page 295
compressa	276	Scirpeaiia mirahilis	179
fascialis	298	Serialaria	251
foliacea	298	imhricata	254
foraminosa	297	lendigera	251
frondijmra	296	verticillala	254
lichenoides	209	Sertularia	121
liliacea	268	abietina	130
pvrmcosa	273	anguina	- 266
retepora	296	antennina	139
reticulata	296	argentea	- 134
Skenei	275	articulata	138
tanialis	298	avicularia	292
truncata	269	bursa	264
tululosa	268	bursaria	264
verrucaria	267	ciliata	290
		cornuta	260
Naisa reptans	311	cupressina	- 135
repens	322	cnscuta	252
Nemertesia antennina	140	dichotoma	150
ramosa	140	dumosa	157
NOTAMIA	263	eburnea	262
bursaria	264	Ellisii	123
loriculata	263	ericoides	122
		Evansii	127
Obelia tuUfera	270	falcata	141
tuhuUfera	270	fastigiata	294
Penna marina	176	iilicula	131
rubra	176	frutescens	149
Pknnatula	175	fuscescens	127
Britannica	176	gelatinosa	152
mirahilis	- 179	geniculata	151
phosphorea	175	Gorgonia	149
PENNATULID^	174	halecina	120
Pherusa tubulosa	271	Hibernica	128
Plumatella	322	imbricata	254
campanulata	311	lendigera	251
Crist al a	311	Lichenastrum	128-138
gelatinosa	233	Lonchitis	138
repens	322	longissima	150
sultana	333	loricata	261
Plumularia	140	loriculata	263
Catharina	147	vniricata	121
cristata	143	myriophyllnm	148
falcata	141	nigellastrtim	124
frutescens	149	neritina	293
myriopbyllum	148	nigra	128
pennatula	145	operculata	- 132
pinnata	145	pennatula	145
pltima	143	pinnata	128-146
setacea	146	pluma	143
Pocillopora interstincta	209	polyzonias	122
Polypes a panache	311	pumila	125
Polypes verds	93	pustulosa	254
Polypus, fresh-water -	93	repens	155-291
Porus cerxnnus	276	reptans	291
Primnoa lepadifera	185	rosacea	124
		rugosa	123
Retepora	296	scruposa	291
cellulosa	297	sericea	250
reticulata	296	setacea	146

INDEX.

;341

Seiitularia	Page 121	Tlbl'laria	Page 118
seticornis	140	indivisa	113
ipinosa	250	larynx	115
ayringa	155	muscoidex	115
tamarisca	130	ramea	117
Templetoni	123	ramosa	116
ternata	263	repens	322
ihuia	137	sultana	32i3
nnijlora	155	trichoides	116
usneoides	132	tuhifex	157
Hva	283	TUBULARIAD^	91
verttciUata	156	TUBULIPORA	- 267
voluhilis	150-154	obelia	- 269
SERTULARIADiE	92	patina	267
		serpens	268
Thoa	119	transversa	268
Beanii	120	truncata	269
halecina	- 119	TUBULIPORIDiE	247
muricata	- 121	TURBINOLIA	206
Savignii	- 117	borealis	206
Thuiaria	137
articulata	138	Ulvu d'laphana	;301
tbuia	137	U nicellaii-e cornet	261
Tricellaria ternata	263	Unicellaire cornue	261
Tubipora catenulariu	265
fasciciilaris	272	Valkeria	252
inusica	272	Cuscuta	252
repens	312	glomerata	254
serpens	268	imbricata	254
verrucosa	273	pustulosa	254
Tubularia	113	spinoia	250
affinis	110	uva	253
calamaris	114	Vesichlaria	250
campaniilaia	311	cuscuta	253
coryna	112	pustulosa	254
fistulosa	295	spinosa	250
flabelliformis	118	VESICULARIAD^	247
gelatinosa	323	ViRGULARIA	179
gigantea	114	mirabilis	179
gracilis	114

EDINBURGH : PRINTED BY JOHN STARK, OLD ASSEMBLY CLOSE.

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