190 THE OCEAN 



Crustacea. — J. R. Henderson states that 

 throughout the entire range of Crustacea there 

 is no better illustration of bipolarity than that 

 furnished by the Lithodidae. Munidopsu 

 antonii is recorded from the Southern Ocean 

 and the south-east Pacific as well as from the 

 north-west coast of Africa. Palcemon squilla 

 of the North Sea closely approximates to 

 P. affinis, though their habitats are the 

 antipodes of each other. The genus Crangon 

 appears to be bipolar. Lophogaster typicus, 

 Boreomysis scyphops, and Amblyops crozetii are 

 also bipolar, and C. Zimmer states that all the 

 genera of Schizopods of the south temperate 

 and cold zones, except two, are represented 

 in the north. Amongst the Cumacea Zimmer 

 says there are six or seven bipolar genera. 

 D'Arcy W. Thompson says there are no bipolar 

 isopods or amphipods, while Pfeffer maintains 

 that numerous species amongst the amphipods 

 are bipolar, like Eurytenes gryllus ( = Lysian- 

 assa magellanica). According to W. Weltner 

 the cirriped Balanus porcatus is bipolar. 

 W. Giesbrecht enumerates six bipolar cope- 

 pods, and G. S. Brady records Harpacticus 

 fulvus from Europe and Kerguelen, remarking 

 that Kerguelen is the locality which of all 

 others has shown in its entomostracan fauna a 

 close resemblance to that of Europe. Calanus 

 finmarchicus, so common in the far north, 



