NEW MALLOPHAGA. 513 



hairs. The posterior margin of the metathorax is angu- 

 lated and the angle projects so far backward that it 

 nearly cuts the first abdominal segment in two. Pro- 

 fessor Osborn's figure is faulty in representing the meta- 

 thorax with straight posterior margin. The male figured 

 by me measures: Body, length 1.06 mm., width .48 mm. ; 

 head, length .34 mm., width .37 mm. 



Physostomum. 

 Physostomum microcephalum n. sp. (Plate lxx, fig. 1.) 



A single female from the House Finch, Carpodacus 

 mcxicanus frontalis (Palo Alto, California). Not com- 

 mon on its host, as I have a record of twelve other indi- 

 viduals of Carpodacus from which Mallophaga were 

 taken, but on none of them was this Physostomum again 

 found. The new species approaches the general type of 

 P. agonum N. (Giebel, Insecta Epizoa, p. 255), from 

 Sylvia rubecula and S . succia more nearly than it ap- 

 proaches any other of the Old World species. 



Description of female. Body, length 3.6 mm., width 

 1.25 mm.; head small; abdomen large and exceptionally 

 broad; head markings pale, ill-defined; distinct brown 

 lateral bands ; paler colored large median transverse ab- 

 dominal blotches. 



Head, length .66 mm., width .72 mm., thus being wider 

 then long, which is exceptional in Physostomum, and being 

 especially small in proportion, to the size of the whole 

 body; front flatly rounded, and sides of forehead weakly 

 concave; prickles on front, one hair on margin at extrem- 

 ity of transverse clypeal suture, and a few very short hairs 

 and two longer ones along margin before the eye ; eye 

 distinct, with a black fleck; palpi passing the margins of 

 head; the blunt lateral flaps slightly passing the margin; 

 temples not produced very far backward, with a little 



