INSECTS OF THE PRIBILOF ISLANDS. 



553 



IX. AGARINA. 



Fig. 1. 



By Prof. Herbkrt Osborn. 



Haematopinus callorhini Herbert Osborn, new species. (Type, No. 3501, U.S.N.M.) 



Head but slightly produced, less than a semicircle in front of the antennae, wider 

 behind the antennae than in front; eyes inconspicuous or wanting; dorsal surface with 

 a very strong basally swollen lateral bristle and a number of stiff 

 shorter bristles or spines merging anteriorly into short blunt spines; 

 posterior margin subaugular and projected on to prothorax; beneath 

 with long slender bristles posteriorly and short blunt spines anteriorly; 

 antennae five jointed, basal joint very large, succeeding joints gradu- 

 ally diminishing in size but of nearly equal length. 



Thorax wider than long, concave in front and behind, lateral mar- 

 gins rather evenly arcuate; prothorax produced posteriorly, nearly 

 reaching abdomen; sutures of pro- meso- and meta- thorax converging 

 near posterior margin, posterior margin of meso- thorax strongly 

 chitinous, surface bristly and spiny, meso- and meta- thorax each with 

 larger bristles. No sternal plate, coxae wide apart, and surface of sternum scantily 

 armed with short spines. 



Abdomen widest near the middle, tapering to apex; set with short stiff spines and 

 bristly hairs; the spiracles opening in small prominent tubercles; beneath with short 

 spiny hairs. 



Legs nearly uniform in size, middle and posterior ones slightly larger; middle and 

 hind tarsal claws fitting into a semicircular cup on the spur of tibia. 



Genitalia of male located dorsally, most apparent from above, where the chitinous 

 structure is conspicuous, especially the two bars converging forward so as to form a 

 triangle, from base of which, at apex of abdomen, the protruding penis and hooks 

 appear as a second triangle. Length, 2 mm. 



This species falls in Haematopinus, on account of the flve-jointed antennae and 

 structure of sternum, thougli approaching Uchmophthirius in body covering. It is 



perhaps nearest piliferns, but stands pretty clearly by itself, 

 and may doubtless be referred to a distinct subgenus. 



Described from a number of examples from the northern 

 fur seal, Callorhimis ursinus, from Pribilof Islands. 



Ixodes arcticus Herbert Osborn, new species. (Type, No. 3500, U.S.N.M. ) 



Elongate oboval slightly contracted behind the middle, 

 finely transversely striated; dorsal shield deep chestnut brown, 

 oval except where truncated to join head ; two divergent im- 

 pressed lines or furrows from near the anterior margin to 

 behind the middle, where they terminate abruptly, and exter- 

 nal to which, near their ends, are short, impressed lighter 

 marks, one on either side. Palpi rather short, blunt, truncate at apex, sharp edged, 

 flat, and somewhat impressed above; legs blackish except the joints, long, strong. 

 The dorsum of the expanded abdomen has two deep parallel furrows anteriorly and 

 three posteriorly, and the ventral surface has the ordinary furrows of the genus, much 

 as in ricinus. The color of the alcoholic specimens is a testaceous yellow. Length 

 ot expanded female, 6 mm. Length of dorsal shield, 1.25 mm. ; width, 0.92 mm. 



Fl». 2. 



