98 QUARTERLY CHRONICLE. 



Liitken, is also noticed. His studies liave been more zoolo- 

 gical than anatomical^ and refer not only to the Antedons 

 [Comatuke), but also to the Pentacrini. He shows that the 

 first are not merely Pentacrini detached from their peduncle^ 

 and that the second also are not merely Antedons which have 

 preserved their larval stalk. Amongst fossil Pentacrini but 

 one is known, figured by Buckland, of which the calyx is 

 entirely preserved. From the disc of this animal a sort of 

 recurved rostrum is seen to issue with an aperture at its end, 

 which has been considered the mouth. But since the living 

 Pentacrini, as M. Liitken observes, agree with the Antedons 

 as to mouth and arms, it is evident that the rostrum is an 

 anal tube. Miiller was aware of this. It is, however, to be 

 remarked that among the Comatulae, some, as the Antedons, 

 have a central mouth, with a more or less eccentric anal tube 

 whilst others, as the Actinometrse, have a central anal tube, 

 and a lateral mouth. Therefore we may expect similar dif- 

 ferences in the Pentacrini. Another explanation of the tube 

 of certain fossil crinoids is, that in them the anal and oral 

 apertures are united. If this be the case, it cannot be 

 regarded as in the Ophiuridea, and the Asteridea with conical 

 ambulacral vesicles, as resulting from the suppression of the 

 anal aperture, but rather must be looked at as the assumption 

 of oral functions by the anal aperture. 



Note on the Polymorphism of the Anthozoaria and the 

 Str'ucture of the Tubvporn^^ by Alb. Kolliker. — The polymor- 

 phism of individuals, so remarkable among the Acalephae, had 

 till now no parallel among the other Coelenterata. It is, there- 

 fore, a discovery as little expected as that of a veritable poly- 

 morphism, which Professor Kolliker has made among various 

 genera of Anthozoaria, and Alcyonaria. This polymorphism 

 consists in this, that besides the large individuals susceptible of 

 taking nourishment, and provided with generative organs, 

 there exist also other smaller, asexual polyps, which appear 

 to preside essentially over the introduction of sea-water into 

 the organism, and its expvilsion, and which are, perhaps, at 

 the same time the seat of an excrementitious secretion. 

 These asexual individuals possess, like the others, a body- 

 cavity divided into chambers by eight septa, and a pyriform 

 stomach furnished with two ajiertures. They are entirely 

 destitute of tentacles, and in })lace of the eight ordinary 

 mesenteric filaments, no more than two are found applied 

 over two consecutive septa. The cavity of the body of these 

 individuals is always in communication with that of the 

 sexual individuals, but the manner in Avhich this communi- 

 cation is established is liable to vary with the genera. Two 



