observed between Drontheim and the North Cape. 385 



TUNICATA. 



The species of this class were most abundant on clean ground 

 at a depth of 15-50 fathoms. In Grote fiord, on a muddy- 

 bottom in 20 fathoms water, a species of Cynthia occurred abun- 

 dantly in masses composed of twenty to thirty individuals. A 

 single specimen of Pelonaa corrugata was dredged off the coast 

 of Nordland. 



Amourcecium, M.-Edw. 



argus, M.-Edw. 

 BoTRYLLUS, Gaertner. 

 ' polycyclus, Savigny. 



BOTRYLLOIDES, M.-Edw. 



albicans, M.-Edw. 



AsciDiA, Baster. 



virginea, O. F. Muller. 

 Cynthia, Savigny. 



limacina, E. Forbes. 



aggregata, Rathke. 

 Pelon^a, F. 4" G. 



corrugata, Forbes. 



Note. — We have several other species of this class which we 

 think are not described. 



POLYZOA. 



The number of species collected is about thirteen, of which 

 six at least seem to have been hitherto undescribed. With one 

 exception, those which are known appear to belong to forms met 

 with only in the Arctic or northern part of the temperate zones. 

 The exception, Retepora cellulosa, of which however only a frag- 

 ment occurred, is found in the Mediterranean, and probably in 



Ann. b; Mag. N. Hist. Ser. 2. Fb/. xvii. 25 



