48 NORTH AMERICAN ANOPLURA 



without finding it. We did, however, find eggs, apparently of an Ano- 

 pluran, upon one skin. 



Family ECHINOPHTHIRIIDAE Enderlein. 



Echinophthiriidae Enderlein, Zool. Anz., vol. 28, p. 137, (1904). 



Echinophthiriidae Enderlein, ibid., vol. 29, p. 661, (1905). 



Echinophthiriidae Enderlein, Deutsche Siidpolar Expedition, vol. 10, part. 4, pp. 



476, 505, 506, (1909). 

 Echinophthiriidae Mjoberg, Arkiv. for Zoologi, vol. 6, no. 13, p. 176, (1912). 

 Lepidophthiriidae (in part) Mjoberg, ibid., p. 177. 



Body thick and plump, thickly beset with spines or with scales. Head 

 not prolonged cylindrically, widened posteriorly. Eyes entirely lacking. 

 Antennae four- or five-jointed. Anterior legs smaller than the others, 

 all, however, extremely stout. No distinct sternal plate. Abdomen with- 

 out pleural plates. 



In this family are included all the Anopluran parasites of marine 

 mammals, such as the seals and walruses, and all are adapted by a thick 

 coating of spines or scales to the aquatic life of their hosts. Mjoberg has 

 proposed to divide the group into two families with regard to the pres- 

 ence or absence of scales, but with this view we are hardly inclined to 

 agree. The family is small, containing at present but seven species (we 

 are adding an eighth), of which four occur in North America or Green- 

 land. 



Genus ANTARCTOPHTHIRUS Enderlein. 



Antarctophthirus Enderlein, Zool. Anz., vol. 28, pp. 136-137, (1904). 

 Antarctophthirus Enderlein, Deutsche Siidpolar Exped., vol. 10, pt. 4, pp. 476, 508, 



figs. 172-177, text fig. KK, NN, (1909). 

 Arctophtirus (in part) Mjoberg, Arkiv. for Zoologi, vol. 6, no. 13, p. 177, (1910). 



Antennae five-segmented. Anterior legs and claws much smaller 

 and slenderer than the others. Spiracles small, one pair on the meso- 

 thorax and on each of the third to eighth abdominal segments. Head, 

 thorax and abdomen beset with more or less short, stout spines, and with 

 long hairs. Abdomen beset with scales on both dorsal and ventral sides. 

 Scales present, but much more sparingly, on the thorax. There are at 

 present but four species in this genus: one, A. trichechi (Boh.), occur- 

 ring upon walruses, in the Arctic regions, the other three occurring upon 

 as many species of seals in the Antarctic. Mjoberg has proposed placing 

 A. trichechi in a separate genus, Arctophtirus, but we are unable to un- 

 derstand his reasons for doing so. We have at hand specimens of this 

 species and of another which is undoubtedly new. 



