156 PROCEEDINGS OF THE ACADEMY OF [Feb., 



Station 9. Saunders Island, 5-10 fathoms (1). 



Station 11. Northumberland Island, 10-15 fathoms (3). 



Station 37. Saunders Island, 5 fathoms (14). 



Station 52. Robertson Bay, 5-15 fathoms (1). 



Station 57. Sarkak, Waigat, 9 fathoms (10). 



Distribution. — Denmark, Norway, Finmark, Labrador, North, 

 West and East Greenland, Jan Mayen, Spitzbergen; 2-100 

 fathoms 



North Greenland: Cape York (Hansen). 



35. Synidotea marmorata (Packard). 



Benedict, Proc. Acad. Phila., 1897, p. 392, fig. 2. 



Station 60. Battle Harbor, Labrador, 12-14 fathoms (2). 



Distribution. — St. Lawrence Gulf (Whiteaves), Newfoundland 

 Bank, 36-129 fathoms (Benedict); Labrador: Kynetarbuk Bay, 

 1 fathoms (Packard). 



36. Arcturus baffini (Sabine). 



A. baffini and feildeni Benedict, Proc. Biol. Soc. Washington, Vol. 12, 

 1898, p. 43. 



Station 26. Cape Alexander, 27 fathoms (62). • 



Station 27. Cape Chalon, 35 fathoms (13). 



Station 39. Granville Bay, 30-40 fathoms (3). 



Station 40. Granville Bay, 20-30 fathoms (several hundred). 



Station 45. Barden Bay, 10-40 fathoms (1). 



Station 49. Olriks Bay, 15-20 fathoms (109). 



Stalion 51. Robertson Bay, 35-40 fathoms (85). 



Station 52. Robertson Bay, 5-15 fathoms (1). 



The large amount of material at hand enables me to pronounce 

 A. baffini and feildeni varieties of one and the same species. We 

 possess both forms, and the var. feildeni prevails for instance at 

 Station 40, and is represented at Station 49. But, besides, there 

 are many intermediate specimens in the different hauls, especially 

 in Nos. 40, 49 and 51. 



Miers found his feildeni under the same conditions, associated 

 with the typical form. Benedict's and Sars' material consisted 

 only of a few individuals of each form. 



Very young individuals are always without spines, and thus 

 young individuals always belong to the var. feildeni, although their 

 mother, to whose antennae they cling, may be a true baffini. In 

 larger individuals the spines are developed in a different degree, 



