INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 481 



MOLLUSCA. 

 Gastropods. 



Page. 



Illyanassa obsoleta 479 



Nassa vibex 479 



Astyris lunata 479 



Anachis avara 306 



Bittium nigrum 479 



Triforis nigrocinctus 305 



Littorinella niinuta. 

 Crepidula convexa . 



Dotocoronata 



Elysia chlorotica . . , 

 Elysiella catulus . . 



Lamellibranchs. 



Page. 



Argina pexata 309 



Mytilus edulis 470 



Pecten irradians . . 

 Ostrsea Yirginiana 



469 

 479 



480 

 480 

 480 



Page. 

 361 



472 



Ascidians. 



Page. 

 Molgula Manhattensis 311 



Botryllus Gouldii 375 



Bryozoa. 



Page. 



Bugula turrita 311 



Vesicularia dichotoma 404 



Escliarella variabilis . . 

 Membranipora, lineata 



Page. 

 312 

 406 



RADIATA. 



AcalepJis. 



Page. 



Obelia diaphana 327 



Obelia, sp 476 



Hydractinia polyclina . 



Polyps. 



Sagartia leucolena 



Page. 

 328 



Page. 

 329 



III. 5. — Animals living on or among piles of wharves, bridges, 



FLOATING TIMBER, ROCKS, ETC., IN BRACKISH WATERS. 



The piles of wharves in brackish harbors are often inhabited by an 

 abundance of animal life. The same species are mostly to be found also 

 on piles of wharves in the purer waters of the sounds, and many of them 

 have, therefore, already been mentioned in a previous place, (p. 378.) 

 There are some of these species, however, that appear to nourish best 

 in waters that are decidedly brackish. 



Among the most conspicuous of these is the beautiful Tubularian 

 S. Mis. 61 31 



