74 



BULLETIN OF THE BUREAU OF FISHERIES. 



PelEcypoda — Continued. 



Clidiophora gouldiana (58). 



Corbula contracta (33). 

 Gastropoda: 



Tritia trivittata (88). 



Anachis avara (40). 



Astyris lunata (48). 



Crepidula fornicata (65). 



Crepidula plana (62). 



Gastropoda — Continued. 



Polynices heros (60). 



Polynices triseriata (35). 

 Cephalopoda: 



Loligopealii (37). 

 Pisces : 



Raja erinacea (31). 



Lophopsetta maculata (31). 



In the foregoing table it will be noted that only nine species (those italicized) have 

 not already appeared in one or more of the lists for Vineyard Sound or Buzzards Bay. 

 And not all these nine are species whose distribution has been determined by temperature ; 

 for example, Ovalipes, Raja, and Lophopsetta (see below). Such a list is thus ill adapted 

 to displaying the peculiarities of the fauna occupying the colder waters of the region. 

 But an examination of the distribution charts reveals the presence of a considerable 

 number of species which are chiefly or wholly restricted to the colder waters under con- 

 sideration. A list of these has been given below, along with the recorded range of each 

 upon the North American coast. It will be seen that in 15 out of 20 cases the range of 

 these species is predominantly northward, some of them, indeed, being near their 

 southern limit of distribution. The presence of three of the others {Ovalipes ocellatus, 

 Molgula arenata, and Lophopsetta maculata) is sufficiently explained by the nature of the 

 bottom at the western end of the Sound, since these are characteristic sand-dwelling 

 species. 6 



X. Species restricted to, or at least occurring predominantly in, the colder waters of Vineyard 

 Sound and Buzzards Bay. (Limited to species occurring at 10 or more stations.) 



Ccelenterata: 



Eudendrium dispar. — Vineyard Sound to Bay of Fundy. (N.) 



Alcyonium carneum. — Rhode Island to Gulf of St. Lawrence. (N.) 

 Echinodermata: 



Asterias vulgaris. — Labrador to Cape Hatteras, but not littoral south of Woods Hole. (N.) 



Strongylocentrotus droebachiensis. — Circumpolar, south to New Jersey. (N.) 

 Crustacea : 



Calliopius laeviusculus. — Narragansett Bay to Greenland. (N.) 



Pontogenia inermis. — Vineyard Sound to Arctic Ocean. (N.) 



Pagurus acadianus. — Grand Bank to mouth of Chesapeake Bay. (N.) 



Ovalipes ocellatus. — Cape Cod to Gulf of Mexico. (S.) 

 Mollusca: 



Pecten magellanicus. — Labrador to Cape Hatteras. (N.) 



Modiolaria nigra. — Arctic seas to Cape Hatteras. (N.) 



Crenella glandula. — Arctic seas to Cape Hatteras. (N.) 



Venericardia borealis. — Arctic seas to off Cape Hatteras. (N.) 



Astarte undata. — Gulf of St. Lawrence to Cape Hatteras. (N. and S.) 



Cyclas islandica. — Arctic Ocean to Cape Hatteras [in deep water]. (N.) 



Thracia conradi. — Labrador to Cape Hatteras. (N.) 



Buccinum undatum. — Arctic seas to Charleston Harbor. (N.) 



Crucibulum striatum. — Nova Scotia to Florida Keys. (S.) 



a See p. 184 for standard employed in grouping species as "northward ranging" or "southward ranging." 

 b Ovalipes and Lophopsetta. indeed, are known to occur on sand flats at various points throughout the region, irrespective of 

 temperature. 



