184 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [478] 



Ascidians. 



Page. 

 Cynthia partita 311 



Page. 



Molgula Manhattensis 311 



Bryozoa. 



Page. Page. 



Bugula turrita 47G | Vesicularia dichotoma 476 



Escharella variabilis 476 ! Alcyonidium hirsutum 476 



Membranipora lineata 406 Pedicellina Americana 405 



RADIATA. 



Ecliinoderms. 



Page. 



Asterias arenicola 476 



Acalephs. 



Page. 



Obelia gelat inosa 391 



O. diaphana 327 



Page. 



Halecium gracile 476 



Sertularia ar gen tea 408 



O. pyriformis 390 



Polyps. 



Page. 



Metridium marginatuin . . . . 329 



Page. 

 Sagartia leucolena. . 329 



PROTOZOA. 



Sponges. 



Page. 



Page. 



Tedania, species . 330 Eed branching sponge 476 



Halichondria, sp 330 ! 



III. 4. ANIMALS INHABITING EEL-GRASS IN BRACKISH WATERS. 



A large portion of the shallow parts of nearly all the harbors, estu 

 aries, and ponds is occupied by a dense growth of eel-grass, Zostera 

 marina, in summer. This plant flourishes both on sandy and muddy 

 bottoms. During the fall and winter it is mostly torn up and drifted 

 away bj storms, but in the spring a new crop starts up and grows very 

 rapidly, the narrow, ribbon-like leaves often becoming six feet or more 

 in length during the summer. 



These tracts of eel-grass are the favorite resorts of a considerable 

 number of animals, which seek these places either for food or conceal 

 ment and shelter, or for both combined. Other species, including certain 

 hydroids, bryozoa, and ascidiaus, grow attached to the leaves of the 

 eel-grass. 



