622 



POLYPI. 



The common body has the appearance of a naked fleshy mass, 

 with the p >lypi protruding from its surface, ami in the centre 

 is placed an mornnk axis, resulting Irom some deposition of 

 the animals in the same manner as the outer covering in the 

 other orders. Some of these compound animals float freely 

 in the water, and others remain at the bottom in the mud or 

 mud. Many of them diffuse a vivid phosphorescent light. 



Umbellulartti Giefiilaniiica. PI. 75, i. 13. Body free, con. 

 Bisting of a long simple stem, with a bony inarticulated axis, 

 enveloped bv a fleshy membrane; polypi large, congregated 

 in an umbellate mass, each provided with eight ciliated tenta- 

 cula. Stem slender above and lengthened, the polypi crowded 

 on mi umbel at the apex. Inhabits the Northern Ocean. 



I irgularia. Body free, filiform or linear, greatly elongated, 

 partly surrounded by polypiferous pinnulae, and enveloping a 

 btony axis; pinnules numerous, small, distichous, transverse, 

 and surrounding the stem at the top. Inhabits the Northent 

 Ure;in. 



lifttilla. Body free, depressed, kidney-shaped, placed on a 

 pedicle, with one of the fares polypiferous, and striated rays 

 on tin' oilier; polypi provided with six rays each. 



f'ennatulu phosphorea. PI. 75. f. 14. Body free, fleshy, 

 penniform, pinnated above, with the lower part of the stem 

 naked, and containing a cartilaginous or bony axis ; pinnulae 

 distichous, open, depressed, plicated, and polypiferous in their 

 upper margin; polypi with radiated tentacula. Fig. 65 re- 



e-esents some of the polypes greatly magnified. Inhabits the 

 ritish seas. 



FitHtculina. Body free, filiform, very simple, long, fleshy, 

 and provided with warts, or polypiferous papillae, arranged in 

 longitudinal rows; axis slender, horny, or of a substony 

 consistence in the centre ; polypi solitary, placed upon each 

 wart. Inhabits the American ocean. 



yeretilliun. Body free, fleshy, simple, cylindrical, polypi- 

 ferous above, and with the base naked, and more or less cori- 

 aceous ; polypi seated, and thickly studded on a body common 

 to the community ; each provided with eight ciliated teuta- 

 cula. 



ORDER II. POLYPI TUBIFERI. 



Polypi united in a common fleshy body, either simple, lobed, 

 or ramified, and constantly fixed at its base ; destitute of any 

 solid internal axis ; surface entirely or in part covered with 

 tubiform cylinders, rarely retractile ; mouth terminal, pro- 

 vided with eight pectinated tentacula. 



The tubiferous polypi always exist in the form of a fleshy 

 gubgelatinous body, invariably fixed by their base. They are 

 more or less simple, convex, lobed, or slightly ramified. The 

 upper part of the surface of their body is covered with a vast 

 number of small tubiform movable cylinders; having at their 

 summit a roundish sub-octagonal mouth surrounded by eight 

 pectinated tentacula. 



LobultiHa digitata. PI. 75, f. 15. Common body of a 

 fleshy consistence, elevated upon the base, but seldom sup- 

 ported by a short stem, simple, or provided with lobes ; sur- 

 face thickly studded with polypi, which are totally retractile, 

 cylindrical, with eight external grooves, and eight pectinated 

 tentacula. Inhabits the coast of Europe. Fig. 16 is a magni- 

 fied view of a portion of this species. 



Cliona. Of a fleshy, irritable substance, provided with 

 siliceous spicula; generally embedded in the cavities of shells, 

 and stretching out contractile papillae, on the margin of which 

 are placed cylindrical polypi, furnished with eight tentacula. 

 Inhabits empty oyster shells on the British coasts. 



Ammothea. With the common body divided into many 

 short and branched stems, the last branches clustered, oval- 

 conoid, and studded with polypi, which are not retractile ; 

 bod y short, with eight pectinated tentacula placed on the sides. 

 Inhabits the coasts of the Red Sea. 



Xenia. The common body provided with thick, somewhat 

 short, naked stems, emanating from the base, and divided at 

 their summit, polypiferous at their extremity ; polypi not 

 capable of retractility, cylindrical, fasciculated, in the form of 

 an umbel, and clustered at the summit of the branches into 

 globular heads, provided with eight large deeply pectinated 

 tentacula. 



Anthelia. Common body spread out in a thin plate, or de- 

 pressed over marine substances; polypi destitute of retractile 

 powers, protruded, straight, and crowded, over the surface of 

 the common body ; provided with eight pectinated tentacula. 

 Inhabits the shores of the Red Sea. 



ORDER III POLYPI VAGINATI. 



Each individual polype tentaculated, constantly fixed in an 

 inorganic body, or sheath, which completely envelops them, 

 and forming in general compound animals. 



This is the most extensive class of polypi, and is divided into 

 seven sections. The animals are very delicate, transparent, 

 and extremely contractile, usually fixed in an inorganic body 

 of their own formation. This calcareous mass is increased 

 in size with every successive generation : and these, in the 

 course of time, accumulate to such a size, that they raise 

 islands in the midst of the ocean. The cells are short, long 

 or tubular, the orifice sometimes irregular, and at others regu- 

 lar; the interior wall?, being simple, longitudinally striated 

 or lamellated, and stelliform. 



SECTION I. 



The polypiferous masses composed of two distinct parti ; 

 thejirit consisting of numerous horny fibres, either in fasci- 



culi, radiated, interlaced, crossed, or fitted together; tlic ><>rond 

 is composed of a fleshy or gelatinous pulp; covering, enve- 

 lopintj. r attaching the fibres, containing the polypi, and as 

 sumii.g in drviiur a consistence more or less firm. 



Alcyonium Oorgonoides. PI. 75, f. 9. The polypifejous, 

 masses are polymorphous, soft, or fleshy, when recent; but 

 some what coriaceous and firm when dried; composed of small, 

 horny fibres, interlaced, agglutinated together by means of a 

 persistent pulp; osculi usually apparent, and variously disposed 

 at the surface; polypi generally provided with eight tentacula. 



Ggoditt. The polypiferous muss tree, fleshy, tuberous, hol- 

 low interiorly ; hard when dry ; the whole exterior surface 

 porous | lateral face, with a cluster of isolated orifices larger 

 than the pores. 



Tethia. With a knotty subglobular polypiferous mass, the 

 interior with numerous, fasciculated fibres, radiating Iroin the 

 interior to the circumference, and agglutinated together by a 

 pulp; crust provided with horizontal cells ; osculi caducous, 

 and seldom perceptible. 



Spongia tubulosa. PI. 75, f. 5. Polypiferous mass soft, 

 gelatinous, very flexible, and fixed; the cartilaginous matter 

 supported by calcareous or siliceous spicula; pores excessive! y 

 numerous and irregular. The spicula are represented at figs. 

 71 and 72, pi. 75. It will be seen by the Spongia coalita, pi. 

 75, f. 70, that there are two kinds ot orifices ; the larger hav- 

 ing a rounded shape, provided generally with raised margins, 

 which form projecting papillae, the smaller being much more 

 numerous, exceedingly minute, and constituting what are 

 termed the pores of the sponge. 



Flabellaria pavonia. PI. 75, f. 17. The polypiferous mass 

 is caulescent, fan-shaped, incrusted, frequently divided, with 

 the expansions depressed, subarticulated, and polypiferous ; 

 stem cylindrical, short; the tissue composed of interlaced 

 fibres; articulations somewhat kidney-shaped; broader than 

 long, upper margin rounded and sinuous. Inhabits the seas of 

 America. F. mcrassata pi. 75, f. 2- 



Penicillus capitatus. Pi. 7S, f. 18. Polypiferous mass, 

 supported on a simple, exteriorly incrusted stalk, filled inte- 

 riorly with many horny fasciculated fibres, and divided at its 

 summit into a cluster of filiform dirhotomns, articulated 

 branches. Fig. 19 shows the articulations magnified. 



SECTION II. 



The polyp : ferous masses branched like plants, and composed 

 if two kinds of substance, namely, a central solid axis, and a 

 fleshy incrustation, which invests and contains the polypi; 

 axis inorganic, corneous, or stony ; when dried the polypifer- 

 ous crust is porous, cellular, and friable. 



Corallina corniculata. PI. 75, f. 11. Polypiferons mass 

 adherent, greatly branched, having a central axis, and an 

 interrupted incrustation; axis filiform, inarticulate, solid, 

 cartilaginous, or horny; incrustation calcareous, dense, 

 united at the surface, and destitute of distinct cells, inter- 

 rupted, and as if jointed longitudinally. The animals unknown. 

 Inhabit the American and European seas. Fig. 4 is a magni- 

 fied view of some branches. 



Gorgonia verriculata. PI. 75, f. 8. Polypiferous mass 

 branched and adherent, having a central axis and an outer 

 bark ; axis fixed at the base, caulescent, branched, externally 

 substriate, solid, horny, and flexible, the fleshy covering en- 

 veloping the axis and branches, and in its fresh condition 

 containing polypi ; when dried it is spongy, porous, and 

 friable ; invested by superficial or projecting cells. Indian 

 seas. 



Antipathes spiralis. PI. 75, f. 20. Polypiferous mass ad- 

 herent, branched ; consisting of a central axis and outer 

 envelop ; axis provided with a foot, and fixed by the base, 

 caulescent, simple, or branched ; corneous, solid, flexible, and 

 usually rough, with small spines; envelop gelatinous, poly- 

 piferous, covering the axis and its branches when alive, but 

 disappearing when removed from its native element. Indian 

 ocean. 



Iris hippuris. PI. 75, f. 21. Polypiferons mass arborescent, 

 fixed, composed of a central, branched, jointed axis, forming 

 stony striated articulations, horny between the joints, and an 

 outer envelop, which, in the fresh state, contains polypi, but 

 which disappear when out of the water. Indian ocean. 



Melitcea. Adherent, tree-shaped, having a jointed knotty 

 axis, and a persistent envelop ; central axis branched, caul- 

 escent, and formed of stony substriated joints, with spongy, 

 gibbous intervals ; envelop cortical ; containing polypi when 

 in the water ; thin, celliferous, and persistent when dried. 



Corallium rubrum. PI. 75, f. 6. Adherent, branched, stiff, 

 and devoid of articulation ; axis caulescent, branched, stony, 

 and solid, with the surface striated ; envelop soft and fleshy 

 in the recent state, in which are lodged the polypi ; when 

 dead, thick, porous, and red ; mouth of the polypi provided 

 with eight ciliated and radiated tentacula. Fig. 7 represents 

 one of the polypi greatly magnified. Indian ocean. 



SECTION III. 



With stony polypiferous masses, having star-shaped, 01 

 waved laminar furrows. 



1. WITH LATERAL STARS, OR SPREAD OVER THE SURFACE. 



Oculina prolifeia. PI. 75, f. 22. Polypiferous mass of a 

 stony consistence, generally with adherent, smooth, thick, and 

 very short branches ; some of the star-shaped mouths termi- 

 nal, the others lateral and superficial. Northern ocean. 



Seriatopora tubulata. PI. 75, f. 23. Adherent, stony, with 





