G. Y. and A. F. Dixon — On Bunodes thattia, etc. 317 



was exactly similar to Jourdan's figures of the wall of Bunodes 

 verrucosa ; but the result of his iuvestigatious led him to see that 

 the warts were solid growths of connective substance, and he 

 accordingly declared himself to be against the acceptation of the 

 term " verrues glandulaires." We believe the evaginations above 

 described to be the warts, for the following reason : the rows of 

 warts are in the living specimen seen to lie in each alternate space 

 enclosed between the lines marking the insertion of the mesenteries, 

 that is, in the endocceles, or possibly (so far as external exami- 

 nation can show) in the exocceles ; but a series of transverse 

 sections made throughout the entire animal show these evagina- 

 tions occurring only in the endocceles ; and a longitudinal section 

 through an endocoele displays them in numbers, while a longi- 

 tudinal section through an exoccele exhibits none. It is needless 

 to observe that no other than a papilliform or wart-like structure 

 would appear as an evagination, both in the transverse and the 

 longitudinal sections (PL iv. figs. 3 and 4). If further proof is 

 necessary, we may add that these structures are found in sections 

 of Bunodes verrucosa, Bunodes ininuta, Tealia bunodiformis, and Tealia 

 crassieornis, as well as in the form now under discussion, and all 

 of these species are known to possess warts of similar appearance, 

 while the suckers possessed by the genera Sagartia and Oylista 

 are very different in appearance. 



The Mesenteries. — Each mesentery possesses two well- developed 

 endodermal longitudinal muscles (PI. v. fig. 1). The mesoglcea in 

 the chief longitudinal muscle is thrown into a complicated series 

 of pleatings, along which the muscle fibres are arranged, the whole 

 exhibiting, in transverse section, what Professor Hertwig has well 

 termed a " meandrous complication." The second longitudinal 

 muscle lies close to the body wall on the same side of the mesen- 

 tery, while on the other side there is seen projecting into the 

 exoccele a strong parieto-basilar muscle. The two last mentioned 

 muscles are found to be more strongly developed in sections cut 

 near the base. Follicles containing spermatozoa were found on 

 some of the mesenteries in some of the specimens, but no ova were 

 detected. The usual unicellular glands were present in the free 

 edges of the mesenteries. 



The mesenteries are arranged in pairs, and are indefinite in 

 number; one specimen we found to possess thirty, one twenty-three, 



