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BULLETIN 124, U. S. DEPARTMENT OE AGBICULTURE. 



The malachiid beetle, Collops vittatus Say (fig. 18), is rather 



numerous in the alfalfa fields of Arizona and was suspected of bear- 

 ing some relation to Eurymus. 

 Mr. T. Scott Wilson found both 

 adults and larva? feeding upon 

 pupa? of the alfalfa caterpillar. 

 He observed as many as 20 beetles 

 feeding upon as many pupa? in a 

 single day. This beetle seems to 

 feed upon either live or dead 

 Eurymus larva? and pupa? and does 

 not appear to have much choice 

 between the two. It attacks a pupa 

 or larva and, piercing it, sucks 

 the juices that exude. In this way 

 a hole is gradually made in the 

 host, which, of course, is killed. 

 Being small, the beetle does not 

 consume much of its prey, but 

 wanders off, and the next time it 

 is hungry it attacks a new pupa or 



larva and thus kills many. Larva? were taken in the act of feeding 



upon Eurymus pupa?, placed in vials, and reared to adult Collops. 

 Two species of ants, Pogonomyrmex harhatvs Smith and Gre- 



mastogaster lineolata IcbvIus- 



cula var. clara Mayr (?) were 



observed to attack Eurymus 



larva? and kill them. Several 



species of robber flies have 



been observed to catch the 



adult butterflies and feed 



upon them. The writer took 



P r o c t a c ant hu s milker til 



Macq. with a butterfly in its 



claws, and Mr. H. E. Smith, 



at Koehler, X. Mex., observed 



the butterflies being carried 



off by Stenop>ogon picticornis 



Loew (fig. 19). 



A FUNGOUS ENEMY. 



Fig. 18. — Collops vittatus, a beetle that 

 preys upon the alfalfa caterpillar. 

 Greatly enlarged. (Original.) 



Fig. 19. — Steiwpogon picticornis, a robber fly 

 that preys upon alfalfa butterflies. Not 

 quite natural sizp. (From C. X. Ainslie.) 



A fungus was found to at- 

 tack the pupa? in the Salt Eiver Valley in 1912. This is sometimes 

 quite common, but never abundant, although more prevalent about 

 August than at other times, probably owing to higher humidity. Dr. 



