292 UNITED STATES NATIONAL MUSEUM BULLETIN 2 76 



obtained from only 159 of these collections, despite the fact that more 

 than one egg mass was obtained for many collections. In addition, the 

 percent of parasitized eggs was very low in nearly e\^cry case. This 

 supports the generally held idea that egg parasites are relatively un- 

 important as control factors influencing Malacosoma populations. 



No biological information is given, since the primary purpose of 

 this study was not the study of parasites. Consequently very little 

 biological information could be obtained. See Langston (1957) for the 

 most recent synopsis of egg parasites of western Malacosoma, and for 

 references to other pertinent literature. Dr. H. M. Kulman, Department 

 of Entomology, Fisheries and Wildlife, University of Minnesota, has in 

 preparation a key to the known egg parasites of Malacosoma. 



It is possible that a few of the following records are erroneous, 

 since the egg masses were not removed from the host twigs, and scale 

 insects, eggs of other insects, etc., may have been present from which 

 parasites could have emerged. This appears unlikely, however, since all 

 of the described species of parasites listed here except Dirhicnus sp. 

 have been recorded from Malacosoma eggs in the past. Seven species of 

 egg parasites were collected during this study. They are: 



Scelionidae: Telenomus clisiocampae Riley. This species was found 

 in 41 collections and was widely distributed, although it was most com- 

 monly collected in California, Langston (1957) reported Telenomus 

 clisiocampae from the Great Basin areas, and Telenomus sp. from the 

 coastal areas of California. It is probable that our specimens from 

 coastal California identified by Dr, Marsh as T. clisiocampae are the 

 same as those reported by Langston as Telenomus sp. 



Eulophidae : Tetrastichus malacosomae Girault, This species was found 

 in 62 collections and was widely distributed, although it was virtually 

 absent from the Pacific coastal areas, and was most common in Arizona, 

 Langston (1957) also found it to be quite rare in the coastal areas of 

 California, and more abundant in the Great Basin and Sierra Nevada, 



Eulophidae: Tetrastichus sp. This species was found in only three 

 widely scattered localities (California, Montana, and Utah). 



Eulophidae: Ablerus clisiocampae (Ashmead), This species was found 

 in only four eastern localities (three in Texas and one in Missouri), 

 but was collected from three diflferent hosts (americanum, disstria, and 

 tigris). Apparently, it has not been collected west of the Great Plains 

 (see Langston, 1957), 



Eupelmidae: Anastatus sp. This species was found in 12 collections, 

 of which 9 were from California. The other three collections were 

 from Texas, Arizona, and Utah. Five of the nine California localities 

 were in the Modoc County area where Langston (1957) first recorded 

 it from Malacosoma eggs. 



