59 



spotted Diabrotica eating the leaves. The plums and the apricots were 

 selected out by the beetles, and except in a few instances nothing else 

 was touched. The exceptions were the Governor Wood Cherry and the 

 Hansen Raspberry, which were slightly injured. The attack began 

 upon trees planted in the old melon patch above mentioned. The plums 

 and apricots in the immediate neighborhood were soon stripped of foli- 

 age, and the insects spread over nearly the entire orchard. The first 

 and second growth of leaves were almost entirely devoured and the third 

 growth was much injured. Many of the trees partly succumbed to the 

 attack and some were killed entirely. The injury was quite severe and 

 amounted to several hundred dollars. The injury was not entirely due 

 to the Diabrotica, although Mr. Bowers, who is a very good observer, 

 states that this insect was by far the most numerous of any of the spe- 

 cies found upon his trees. The well-known weevil — Epiccerus imhrica- 

 tus — occurred in small numbers and attacked the foliage to some slight 

 extent, and one of the common May beetles — probably Lachnosterna 

 fusca — was also present on some few evenings instill smaller numbers. 

 Another Scarabteid {Diplotaxis sp.) was also noticed. There seems, how- 

 ever, no doubt but that the main damage was done by the Diabrotica, 

 and this instance is certainly the most marked which has ever been 

 brought to our attention of damage done to fruit-trees by this species. 

 It is safe to say, however, that this occurrence is exceptional, and that 

 it depended almost entirely upon the peculiar circumstance of a young 

 orchard having been planted close to a last year's melon patch, which 

 was not replanted this year. The beetles undoubtedly bred upon the 

 melons last season and hibernated in large numbers. The present 

 spring, finding no more appropriate food at hand they took to the young 

 plums and apricots merely as a substitute. We have little fear, there- 

 fore, that a new habit has been formed. 



The above facts are gathered from correspondence with Mr. Bowers 

 and from observations made by Mr. Alwood, who visited Herndon at 

 our direction on the evening of June 13th. 



HEAT EVOLVED FROM THE WORK OF A BRUCHUS. 



In June, 1887, Judge Lawrence Johnson, of the D. S. Geological 

 Survey, a member of the Entomological Society of Washington, sent 

 to the Division from Holly Springs, Miss., a small quantity of Cow 

 Peas {Bolichos spp.), which were badly infected by Bruchus soutellaris, 

 and in his accompanying note mentioned a circumstance which is worthy 

 of record, as we do not recollect to have seen anything similar in print. 

 The peas when he first examined them were contained in a paper sack, 

 which would hold about one gallon, and which was about one-third full. 

 Resting the bottom of the sack accidentally upon his hand he noticed 

 that it was very perceptibly warm. He then tested its heat with an or- 

 dinary thermometer and found that while the temperature of the air was 



