128 BULLETIN OF THE 



Thyonidium conchilcgum Poubt. 



Body very flaccid. Eighteen to twenty tentacles of unequal size, very 

 little ramified, short, with conical papillae ; they are quite difficult to count, 

 as some of them are so small that they may be mistaken for lobes of the 

 larger ones. Suckers in five double rows, with others scattered between. 

 The outer layer of the very thin skin contains a large number of calcareous 

 bodies of the usual type; the base being a square plate with more or less 

 rounded corners, perforated by a round central hole surrounded by eight 

 smaller ones, those at the corners being smaller than those corresponding 

 to the sides of the square. From this plate rise four cylindrical processes, 

 converging towards and supporting a small spiny plate, which projects on 

 the surface of the skin like small warts. These bodies are also plentiful 

 in the suckers up to the terminal disc. In the muscular subcutaneous 

 layer there are patches of smaller bodies formed of agglomerations of 

 round granules. (Esophagial ring provided with retractor muscles, and 

 composed of ten pieces alternately in the shape of a broad letter X and a 

 thin letter T loosely connected. Anus unarmed. Color white, hyaline. 

 Length 2 or .". inches. 



This animal covers itself with shells of Pteropods, particularly those pro- 

 vided with {joints, one of which seems to be held by every sucker of the 

 body. 



It is probably closely allied to T. pellucidum of the northern seas. 

 Not being able to compare specimens, I base this species chiefly on the 

 difference of the number of perforations in the calcareous plates of the 

 skin, the T. pellucidum having four large holes surrounded by twelve 

 smaller ones. 



Eourgueticrinus Hotessieri D'Orb. 



Several specimens of a living Crinoid were obtained by dredging in 237, 

 248, and 30G fathoms off the Samboes and off Sand Key, in a bottom of 

 Globigerinae and other deep-sea Foraminifera. They undoubtedly belong 

 1<> the genu-; Bourgueticrinus, as defined by D'Orbigny. I refer them pro- 

 visorily to the species named above, founded on some small fragments of the 

 stem discovered in the recent breccia of Guadaloupe, which contained the 

 well-known human skeleton now in the British Museum. D'Orbigny gives 

 it as his opinion that his species is probably still living in the West Indian 

 seas; hut bis figures are. insufficient either to prove or disprove the identity 

 of cur species with his. A comparison with his specimens even would leave 

 the matter in doubt. It is to he hoped that further researches in the 

 Guadaloupe formation will bring to light specimens perfect enough to set- 

 tle the quesl ion. 



