OBSERVATIONS ON THE FAUNA OF THE ROCK 
BEACHES AT NAHANT, MASSACHUSETTS 
By a. S. Pearse 
{Contimied from Vol. XI (N.S.), pp. 8-S4, 1913) 
VI. ANNOTATED LIST OF SPECIES 
It is of course realized that the following list does not include 
all of the species of animals that exist at Nahant. In fact no 
attempt was made to collect many of the microscopic Crustacea, 
Protozoa, etc. Extended observations at various seasons would 
also doubtless add other species. 
Porifera 
Cliona sulphurea Verrill. Not uncommon in the Chondrus Zone on rock 
beaches. In exposed situations it was sometimes found at higher levels. 
Leucosolenia hotryoides Bowerbank. A dead colony was washed up at 
Station 9. 
Coelenterata 
Clava leptostyla Agassiz. Growing on rocks and Fucus on exposed 
beaches (Stations 1, 5, 6, 10, 13). 
Hydractinia polyclina Agassiz. Found growing on the shells of Pagurus 
acadianus, on empty gastropod shells, and in small rock pool low down on 
the beach at Station 8. 
Tuhularia crocea (Agassiz). Two or three colonies were found in the 
Chondrus Zone on rock beaches. 
Campanularia flexuosa (Hincks). On rock beaches where they were 
exposed to the open ocean; on bare rocks in Chondrus Zone. 
Obelia commisuralis McCrady. Among Ascophyllum-covered boulders 
at Station 5. 
Syncoryne mirabilis (L. Agassiz). Medusae were taken several times at 
Stations 7, 8 and 10. 
Melecterum campanula Eschscholtz. Several were observed during the 
day at Station 10 on June 24 and in the evening the shore water swarmed 
with these beauticul little medusae. Next night only a few were present. 
Sertularia pumila Linnaeus. Abundant everywhere on Ascophyllum 
and the rocks beneath it. Sometimes this sertularian was found growing 
on the bare rocks in exposed situations. 
Aurelia aurata (Lamark). Abundant in Boston Bay on June 28. 
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