490 CALIFORNIA ACADEMY OF SCIENCES. 



so conspicuously larger and presents such constant minor 

 differences that I have made it the type of a new species. 

 The figure of it, however, will serve very well as a means 

 of recognizing the American variety of excisus. 



Var. major Kellogg. Male. Body, length 1.3 mm., 

 width .56 mm.; head, length .44 mm., width .40 mm. 

 Female. Body, length 1.49 mm., width .62 mm. 5 head, 

 length .45 mm., width .42 mm.; the pustulations in lat- 

 eral abdominal blotches more complete and distinct than 

 in the type form of the species. Males, females, and 

 young found on the Cliff Swallow, PetrocJiclidon luni- 

 frons, and on the Tree Swallow, Tachycineta bicolor 

 (Palo Alto, California, and Lawrence, Kansas). 



NlRMUS. 



Nirmus longus n. sp. (Plate lxvii, fig. 1.) 



Taken from the Tree Swallow, Tachycineta bicolor 

 (Lawrence, Kansas), and from the Cliff Swallow, Petro- 

 chelidoti litnifrons (Palo Alto, California). A member of 

 the group interruptofasciati and allied to Nitzsch's N. 

 gracilis (Insecta Epizoa, p. 143, pi. vi, figs. 11, 12), 

 which is only half as large and has but four (Giebel) or 

 two (Piaget) hairs on posterior margin of metathorax, 

 and to Denny's elongatus (Monograph. Anoplur. Brit., 

 p. 140, pi. vii, fig. 4), which has the posterior margin of 

 the metathorax "strongly ciliate," the hairs in Denny's 

 figure being ranged thickly along the entire length of the 

 margin. Both of these two allied species were taken 

 from Hirimdo urbica. 



Description of female. Body, length 2.03 mm., width 

 .38 mm. ; very elongate, pale yellowish brown, with 

 chestnut brown lateral bands and marginal head mark- 

 ings. 



