134 - CALIP^ORNIA ACADEMY OF SCIENCES. 



their near relations among the night-hawks and hum- 

 mingbirds. The finding of an immature and an adult 

 female together on the wren, in addition to a single 

 immature specimen on the swallow, allows us to present 

 new evidence of the agreement of the species in generic 

 characters with Menopon. The Menopon species, ^mces- 

 tum, described in this paper, serves as an easy step 

 from the more typical Menopon type to this peculiar 

 Eureum type with its short, broad head, its short, 

 broad prothorax, and long, heavy legs. Menopon 

 robustum Kellogg (New Mallophaga, II, 1896, p. 528, 

 pi. Ixxii, fig. 3) is of this gradatory type, and pre- 

 sents "a mingling of characters of Menopon, Ancistrona, 

 and Eureum; a short, broad head with strongly chitin- 

 ized, backward-projecting processes on the ventral sur- 

 face like Ancistrona; a thorax like Eureum; and the 

 habitus and general body characters of Menopon^' (Kel- 

 logg, 1. c). Osborn's M. expansum (Insects Affecting 

 Domestic Animals, U. S. Dept. Ag., Div. Ent., Bull. N. 

 S., No. 5, 1896, p. 245, pi. ii, fig. ./'.) from Dolichonyx 

 oryzivorus must also be of this general type. 



Our immature forms correspond with the description 

 and figure (Piaget, Supplement, p. 139, pi. xv, fig. 3) of 

 the species. Our adult female (figured herewith) shows 

 the following characters not referred to, or unconform- 

 able to those in Piaget's description. Body, length 2.25 

 mm., width 1.15 mm.; head, length .34 mm., width 

 .9 mm.; head less flatly rounded in front than in the 

 young, and with a slight median angulation; on each 

 side of this angulation a conspicuous marginal hair, and 

 farther to the side a longer hair not marginal, but ris- 

 ing from just in front of the base of the antenna. 

 Metathorax with two long hairs and three spines in 

 the posterior angles, the three spines ranged along the 



