Mallopliaga from Birds of Costa Rica, Central America 55 



rior margin ; a number of short spines on the lateral portion of 

 the posterior margin of segments one to five ; short hairs along 

 the posterior margins of segments three to seven, thicker in the 

 portion just inside the lateral bands; irregular pitchy brown 

 spots in the lateral portion of segments one to eight, not as wide 

 as segment, a narrow longitudinal clear line separates these 

 spots from the interior of abdomen ; smoky brown transverse 

 bands in segments four to seven, separated by narrow, clear 

 sutures; irregular, lateral, brown spots in eighth segment; inte- 

 rior of segments one to three, and nine, a pale translucent brown- 

 ish. The abdomen has the appearance of having a flattened 

 lateral area, with the whole central portion convex. 



Male. — Body, length 1.54 mm., width .51 mm.; head, length 

 .34 mm., width .50 mm. ; clearer than female, with much smaller 

 metathorax ; abdomen a perfect oval, with lateral spots of regu- 

 lar size and shape in all the segments except the ninth ; posterior 

 margins of all the segments with a row of hairs ; transverse 

 bands on segments three to six separated by wider sutures; 

 genital hooks very large and long, reaching from third to poste- 

 rior margin of the eighth segment, with the anterior two-thirds 

 a single heavy shaft, widening posteriorly and separating into a 

 perfect trident. 



One female and three males collected on Zarhynchiis wagleri, 

 at Juan Vinas, Costa Rica, March, 1902. 



Nitzschia bruneri sp. nov. 



This form is very easily distinguished from piilicaris by the 

 exceedingly short metathorax (length .34 mm., width .71 mm.), 

 by the very slender hind femora and tibiae of the female, and by 

 the paleness of the transverse abdominal bands. Measurements : 

 Female, length 2.50 mm., width .95 mm. ; head, length .50 mm., 

 wndth .66 mm.; male, length 1.96 mm., width .75 mm.; head, 

 length .45 mm., width .61 mm. 



While working over specimens of Nitzschia from Costa Rica, 

 I again went over the material collected from Aeronautes niela- 

 nolencus in Sioux county. Neb., and which I had named: piili- 

 caris, var. tibialis. I now find that some errors were made at 



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