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 



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