53 



The Fauna 



2 

 The 56 0.1m grab samples sieved to 1.0 mm yielded 264 putative 



species (Table 7). Two hundred and thirteen of these were identified 



to the species level. The molluscs, annelids and arthropods were the 



best represented groups accounting for 16.6, 42.0 and 26.1% of the 



species respectively. Species list for individual stations are 



presented in Appendix 2. 



Many of the species occurrences are interesting in terms of their 



presence or abundance. For instance, one of the dominant polychaetes, 



Aglaophamus neotenus, was described only very recently (Blake, 1980). 



Among the isopods, both the Virginian Cassidinidia lunifrons and the 



Arctic Munna fabvicii were found within the limited confines of Casco 



Bay. Undescribed members of the amphipod genera Melita and Monoculodes 



were encountered as were individuals of the genera Bathymedon, Hattmedon 



and Gitanopsis . These latter, and perhaps several other records, 



represent range extensions which will be treated in another 



contribution. 



Density 



2 

 Numbers of individuals ranged from 120 to 36,380/m with a mean of 



2 

 8,743/m (Table 8). The lowest value occurred at station 36 in the wood 



chip deposits while the highest value was recorded at the nearby station 



37 which was located in a mussel reef. Density distribution is 



2 

 presented in Fig. 19. Values exceeding 10,000/m are generally found at 



the offshore stations and at several stations in the lower Bay. 



Three regions of low density stations are noticeable. These are 



stations 47, 49 and 50 in the main channel into the Bay, stations 18, 19 



