478 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



Ascidians. 



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€ynthia partita 311 | Molgula Manhattensis 311 



Bryozoa. 



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Bugula turrita 476 



Escharella variabilis 476 



Merabranipora lineata 400 



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Vesicularia dichotoma 476 



Alcyonidium liirsutum 476 



Pedicellina Americana 405 



BADIATA. 



Echinodernu. 



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 Asterias arenicola • - 476 



AcalcpJis. 



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Obelia gelatinosa 391 



O. diaphana 327 



O. pyrifortnis 390 



Page. 



Halecium gracile 476 



Sertularia argentea 408 



Polyps. 



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 Metridium marginatum 329 



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 Sagartia leucolena. .;« 329 



PROTOZOA. 



Sponges. 



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Tedania, species 330 



Halichondria, sp 330 



Page. 

 Bed branching sponge 476 



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 by 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 ascidians, grow attached to the leaves of the 

 eel- grass. 



