THE ROUGH-HEADED CORN STALK-BEETLE 25 



off by strong winds. Plate I, A, represents a badly injured cornfield 

 in the vicinity of Tappahannock. This field had been replanted 

 several times. There were a. number of fields showing such injury in 

 the vicinity of Tappahannock. 



An interesting discovery in relation to the feeding habits of Eue- 

 theola rugiceps is that it will feed readily on apples, either in breed- 

 ing cages or in the field. This fact was first ascertained by Ezra 

 Shackelford, at Tappahannock, who informed the junior writer that 

 he had found a beetle feeding on a, fallen apple in the orchard. This 

 observation subsequently was verified. 



All efforts to find the beetles feeding under natural conditions on 

 common grasses other than Paspalum spp., and Bermuda grass were 

 futile, though in breeding cages they were induced to accept Panicum 

 lindheimeri and Fmibristylis baldwiniana. The indications, how- 

 ever, are that the beetles do not like these plants, and that they feed 

 upon them only when deprived of all other food. 



Since iron weed (Vernonia noveboracensis) was a common weed in 

 the typical habitat of the species, an experiment was made to ascer- 

 tain if the beetles were capable of utilizing it for food. The results 

 were entirely negative. The junior writer found that the common 

 ragweed (Ambrosia artemisiae folia) , the well-known food plant of 

 Ligyrus gibbosus, was unacceptable to< E. rugiceps in breeding cages, 

 nor could they ever be found attacking these plants in the field. 



One or two correspondents of the Bureau of Entomology have 

 stated that potatoes are occasionally injured by Euetheola rugiceps. 

 To test this point, the junior writer on one occasion buried a few 

 tubers in a cage containing a considerable number of beetles, but the 

 latter apparently took no notice of them. 



At Tappahannock Euetheola rugiceps could never be found attack- 

 ing the common grass locally known as goose-grass (Eleusine indica) , 

 but to ascertain if the beetles are capable of subsisting on it a 

 quantity was transplanted to one of the cages containing the beetles. 

 When examined a week later it was found that a number of the culms 

 had been shredded to some extent at the base, but that in only a few 

 was the injury serious. Evidently the beetles do not willingly feed 

 upon this grass, but may possibly do so to a slight extent if unable to 

 obtain more acceptable food. 



Since the beetles were found to be rather common in one of the 

 timothy-clover pastures at Tappahannock, tests were made to ascer- 

 tain if the beetles would feed upon these plants. In both instances 

 they were untouched. It is probable, therefore, that beetles living in 

 timothy and clover fields derive their sustenance from some other 

 plant associated with them. This, in all likelihood, is Bermuda grass, 

 which is usually common in such fields. • 



Occasionally the adults are accused of damaging rice. The writers 

 have never had an opportunity to study the species in rice-growing 

 sections and are unable to speak on this matter from personal obser- 

 vation. Inasmuch as Euetheola rugiceps in one or two instances was 

 reported as injuring rice, and subsequently proved to be the allied 

 species Dysc'tvetus Irac/iypygus, the writers can not avoid the sus- 

 picion thai :ill other reports of such injury may be cases of mistakes 

 in identification. Superficially the adults of the two species are 

 much alike and may be easily confused by persons not familiar with 

 their distinctive characters. 



