56 M. A. Carnkcr 



that time and that several important points were overlooked, 

 which clearly separate this form from pulicaris, and I accord- 

 ingly give it full specific rank as A^ifcschia hrnneri. 



Nitzschia bruneri, var. meridionalis var. nov. 



Female. — Length 2.73 mm., width .99 mm. ; head, length .52 

 mm., width .76 mm.; male, length 2.18 mm., width .74 mm.; 

 head, length .51 mm., width .70 mm. 



The variety is distinguished from the species by the darker 

 color, being a translucent brown instead of golden, by the ab- 

 sence of a marginal band on the lateral portion of' the meso- 

 thorax, by much darker thoracic and lateral abdominal mark- 

 ings, by more and longer hairs at the posterior angles of the 

 abdomen, by shorter and more spine-like hairs along posterior 

 borders of segments, by much smaller posterior tibiae in the 

 male, and, finally, by a difference in size. 



Numerous males and females collected from Chactura grisei- 

 ventris, at Pozo Azul, Costa Rica, June, 1902. While these 

 specimens closely resemble bruneri, they can b.e scarcely called 

 that, and have accordingly been given varietal rank. 



Menopon tridens costaricense var. nov. 



Female. — Body, length 1.48 mm., width .61 mm.; head, 

 length .32 mm., width .49 mm. ; whole body uniformly translu- 

 cent fulvous, with black tips to the mandibles, black ocular flecks, 

 narrow blackish occipital margin, while the peculiar, characteris- 

 tic, occipital process is deep brown ; occipital margin with four 

 hairs, while the posterior margin of the pro- and metathorax 

 and the abdominal segments is furnished with a' row of stout 

 hairs; just inside the lateral bands is a longitudinal area covered 

 with short, fine hairs. The rotundity of the abdomen is also a 

 prominent character. 



A single female collected from Porzana cincrciccps, at Juan 

 Vinas, Costa Rica, March, 1902. Unlike the varieties described 

 by Mr. Kellogg," this form has the lateral bands of the abdomen 

 uncolored, as Piaget gives for tridens, but while it agrees with 

 the species in this respect, it differs radically in others. 



178 



