BIOLOGICAL SURVEY OF WOODS HOLE AND VICINITY. 1 35 



The 19 commonest species of amphipods are herewith grouped with reference to their 

 known range upon our coast. The ranges stated are those given by Holmes (1905). 



Northward ranging. 



Ampelisca macrocephala OS Halifax to Newport. 



Calliopius laeviusculus Greenland to Narragansett Bay. 



Pontogenia inermis Arctic Ocean to Vineyard Sound. 



Ptilocheirus pinguis Labrador to New England. 



Amphithoe rubricata Labrador to Newport. 



Unciola irrorata Greenland to New Jersey. 



JJginella longicornis Greenland to Narragansett Bay. 



Southward 



ranging. 



PHaustorius arenarius Cape Cod to Georgia, Norway, British Isles. 



Elasmopus laevis Provincetown, Mass., to New Jersey. 



Ericthonius minax Vineyard Sound to Great Egg Harbor, N. J. 



Corophium cylindricum Provincetown, Mass., to New Jersey. 



Caprella geometrica Southern coast of New England to Virginia. 



Of uncertain position. 



Lysianopsis alba Woods Hole. 



Ampelisca spinipes Long Island Sound, Woods Hole. (Norway.) 



Byblis serrata Woods Hole, Newport. 



Batea secunda Woods Hole. 



Gammarus annulatus Vineyard Sound, Gloucester. 



Autonoe smithi Vineyard Sound and Buzzards Bay. 



Jassa marmorata Woods Hole region. 



Thus there seems to be a slight excess of northern over southern species among 

 those 19 amphipods which we have dredged most frequently. Little importance is to 

 be attributed to this fact, however, in considering which element is preponderant in 

 our fauna, particularly since for more than one-third of these commoner species the 

 range is not known with any degree of completeness. 



VI. ISOPODA. 



This order is represented in the local fauna by 25 or more species, of which 10 

 were recorded from our dredging stations and at least 7 more were taken by col- 

 lectors from the laboratory during the progress of the Survey. One of these (Erich- 

 sonella altenuata) is here recorded for the first time for this region. 



Our knowledge of this group in New England waters is due chiefly to the labors 

 of O. Harger and Dr. Harriet Richardson. To the latter authority we are indebted 

 for the identification of some of our earlier specimens, though the greater part of the 

 material was determined by Dr. Osburn. The nomenclature employed by Miss Rich- 

 ardson has been adopted by us without modification. 



Twenty-one species of isopods were listed by Harger in the "Invertebrate Animals 

 of Vineyard Sound," of which only a small proportion were at that time recorded for 

 definitely stated points within the limits of the region. In a later paper (1880) the 

 group was treated much more fully by this writer. 



