222 W. C. ALLEE. 



low tide, support masses of the rockweeds. The water here is 

 constantly changed by the strong tidal current. 



A similar situation, except for the tidal current, was examined 

 at the inshore end of Gansett Bay. The region there is in the 

 form of a triangle with the shore for the long base and with the 

 apex made by a large boulder lying about two rods off shore at 

 low tide. 



A partial list of the animals to be found in this association, 

 divided according to strata, is given in list 5. As might be 

 expected, animals usually found only at or near low tide, occur 

 here well above low tide in some abundance on account of the 

 protection furnished and the water held by the rockweeds. 



List 5. Showing Representative Animals of the Rockweed 

 Association by Strata. 



A. Animals on or Among the Rockweed when Left Exposed by the Tide. 

 Ccelenterata : Arthropoda : 



Clava leptostyla, Amphithoe rubricata, 



Obelia geniculata, Caprella geometrica, 



Sertularia pumila, Balanus balanoides, 



Sagartia lucice. Anoplodactylus lentus, 



Limulus polyphemus. 



Echinoderma: 



Asterias forbesi. Mollusca: 



Mylilus edulis, 



Bryozoa: Littorina litorea, 



Alconidium sp.?, Littorina palliata, 



Bugula turrita, Columbella avara, 



Flustrella hispida. Columbella lunata. ' 



B. Animals from the Rocks Below the Rockweed Stratum from First Six 



Rocks Examined. 

 Porifera : 



Cliona celata, (?) Annelida: 



Microcione prolifera, Harmothoe imbricata, 



Lepidonotus squamatus, 

 Ccelenterata: Hydroides hexagonus, 



Polycirrus eximeus. 

 Sagartia leucolena. 



Arthropoda: 



Echinoderma: Cancer irroratus. 



Asterias forbesi. 



Mollusca: 



Bryozoa: Mytilus edylis. 



Lepralia pertusa, 



Membranipora pilosa. Chordata: 



Schizoporella unicornis. Styela partita. 







