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PROCEEDINGS OF THE NATIONAL MUSEUM 



FiGURK 4. — Pimplinae:Ephiakini, head sclerltes: Delomerisia diprionis Cushman. (1, 



antenna; 2, spiracle; 3, skin.) 



The above key must be regarded as provisional, for, on the present 

 material, it is very difficult to decide on any one characteristic of a 

 genus. This may be due to the fact that Scamhus, to take one exam- 

 ple, is a composite genus. Dr. G. S. Walley (in litt.) has reached such 

 a conclusion on Scamhus from study of the adults. 



Genus Scamhus. — S. hispae (Harris) has been examined (fig. 2a). 

 S. hrevicornis (Gravenhorst) is figured hj Thorpe (1930), S. detritus 

 (Holmgren) by Salt (1931), S. foliae (Cushman) by Dowden (1941), 

 and S. pomorum. (Ratzeburg) by Imms (1918) and by Speyer (1926). 

 S. pomorum has neither lobes on the ventral surface of the labial 

 sclerite nor an enlargement on the hj-postoma as has aS'. hispae. S. 

 hrevicornis, S. foliae and S. detritus have lobes on the ventral surface 

 of the labial sclerite, but an enlargement is not present on the hypo- 

 stoma. The ventral surface of the labial sclerite of S. detritus is more 

 pointed than in other species. These points are of interest since 

 Tromera pomorum (Ratzeburg) and Epiurus hrevicornis (Gravenhorst) 

 are type species of genera sjmon^'^mized under Scamhus. 



Genus Alophosternum. — A. foliicola Cushman has been examined 

 (fig. 2b). The closing apparatus of the spiracle of this genus differs 

 from others of the tribe in its long slender shape (fig. 2B2). 



Genus Calliephialtes. — C. nuhilipennis (Viereck) and C. variatipes 

 (Provancher) (fig. 2c) have been examined. Both species possess 



