96 
Psyche 
[June-Sept. 
NOTES ON NORTH AMERICAN NITIDULIDAE, II: 
CRYPTARCHA SHUCKARD 
By C. T. Parsons 
Biological Laboratories, Harvard University 
The genus Cryptarcha embraces many species which are 
found in all parts of the world. The six species occuring in 
the United States have apparently two origins. Cryptarcha 
ampla, grandicollis, glabra and strigatula n. sp. are closely 
related to the numerous Neotropical forms, whereas the 
smaller concinna and gila n. sp. are more closely related to 
the Palaearctic imperialis Fabr. and its allies. The appar- 
ently two origins are reflected in the two subgenera, which 
are keyed below. 
1. Prosternum broad between the coxae and extending be- 
yond the middle of the mesosternum ; anterior margin of 
the metasternum transverse or broadly rounded ante- 
riorly ; species usually longer than 4 mm. 
Cryptarcha s. str. 
2. Prosternum more or less narrow between the coxse and 
not extending beyond the middle of the mesosternum; 
anterior margin of the metasternum acutely rounded 
anteriorly; species usually shorter than 4 mm. 
Lepiarcha Sharp 
Subg. Cryptarcha s. str. 
This subgenus comprises at least the Palaearctic strigata, 
the North American strigatula n. sp., ample, glabra, and the 
Neotropical species. 
1. Unicolorous above 2. 
Elytra with irregular pale fasciae 3. 
2. Apex of prosternal process rounded ampla Er. 
Apex of prosternal process truncate glabra Schaef . 
