2 PEOCEEDIN"GS OF THE NATIONAL MUSEUM vol. 77 



This American louse, while very large, flat, and broad, is decidedly- 

 different from E. cimicoides. It is without eyes ; there are no lateral, 

 pronotal spine-bearing lobes, and, most significant of all, the poste- 

 rior femora and all of the abdominal sternites are without patches 

 of setae. E, cimicoides^ on the other hand, has all these characters; 

 in fact, it has most of the generic characters that are usually attrib- 

 uted to DennyuSj notwithstanding its great width and large size. 



Eureum is in fact almost a synonym of Dennyus; however, there 

 exist certain characters which separate it from the other swift- 

 infesting species. It undoubtedly should be placed next to them. 

 Likewise the louse from our purple martin should become the type 

 of a new genus. Probably this genus should contain the swallow- 

 infesting species, Tnall&us of Nitzsch, but not the swallow-infesting 

 latifrons of Carriker and Shull, which certainly is a true Dennyus. 



The writer has on hand a rather peculiar new species of Dennyus 

 which has been well drawn by Dr. E. A. Chapin (fig. 4). This 

 species was taken from a swift, Cypseloides niger horealis, on the 

 Pacific coast, and has many of its setae transformed into dark, 

 short, peglike spines. It should be put in a subgenus by itself. Thus 

 we should have the genera Dennyus and Eureum, including all of 

 the swift-infesting species, while a new genus is erected for two of 

 the swallow-infesting species. The following key will show more 

 clearly the relationships of these four groups. 



KEY TO THE GENERA AND SUBGENERA OF THE COMPLEX DENNTDS-EURB0M 



1. Eyes present; pronotum produced laterally into spiniferous lobes; posterior 



femora and certain abdominal sternites with patches of closely set 



setae 2. 



Eyes wanting; pronotum without spiniferous lateral lobes; posterior femora 

 and all of the abdominal sternites without patches of setae. 



Hirundoecus, new genus. 



2. Anterior femora inflated, being about as broad as or even broader than long ; 



setae of transverse abdominal rows not close set ; head and body moderate 



to slender 3. 



Anterior femora but slightly inflated, considerably longer than broad; setae 

 of transverse abdominal rows close set, each being but little more than its 

 width from its adjacent setae ; head and body very broad Eureum Nitzsch. 



3. Setae of head and body normal, none of them being peglike ; eyes double, the 



two on a side being partly fused with each other. 



Dennyus (Dennyus) Neumann. 



Some of the setae on head and body short and peglike and each abdominal 



tergite bearing a posterior marginal row of normal setae alternating with 



peglike spines Dennyus (Ctenodennyus), new subgenus. 



Genus DENNYUS Neumann 



Ferris (1916), in one of his first papers on the Menoponidae, has 

 pointed out the relationship of Dennyus to the genera Myrsidea, 

 Actornithoj^hilus, and Heleonomus in the passession of patches of 

 setae on the ventral surfaces of the posterior femora and on certain 



