24 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



eggs. This has been observed and recorded in a number of in- 

 stances. It has been observed at the Gipsy Moth Laboratory of 

 the Bureau of Entomology in Massachusetts that tachinids would 

 oviposit at times upon larvae covered with eggs, while masses of 



unstocked larvae were abundant close by Similar 



conditions could hardly arise except through man's interference. 



The stunted specimens always exhibit practically 

 the same characters, and if there is any exception, the true status 

 of a specimen is quite recognizable." 



Specimen Nos. 1 and 2 are taken from a series of 14 reared 

 from one pupa of Basilona imperialis. Furthermore it contained 

 in addition to the 14 which emerged one dead Tachinid puparium 

 and a shriveled larva, the puparia were crowded tightly together 

 occupying every available space within the pupa shell. The larva 

 of the host was collected from nature at Catawissa, Pennsylvania 

 and sent to the Division of Zoology at Harrisburg, Pennsylvania, 

 where H..O. Marsh made the rearing. E. imperialis is a native 

 species and since there is practically never an abnormal plentitude 

 of these large insects, at most, never so many as to upset the 

 equilibrium of nature, it must be admitted, in the light of the 

 facts noted below, that too many larvae fed upon this individual, 

 to permit of a full development of the resulting adults. There 

 is no evidence here of "mans interference." 



Specimen number seven was reared from a pupa of B. imperialis 

 collected from nature as a larva at Rockville, Pennsylvania, by 

 A. B. Champlain. It will be seen that it measures 4 mm. longer 

 and is very much more heavily bristled than specimens number 

 one and two. It was the sole inhabitant of the host pupa, which 

 was rather a small one for the species. But that this Tachinid 

 is capable of still further development is shown by the measure- 

 ments and chaetophorous adornments of examples 8, 9 and 10. 

 So it may be assumed that had more food been available for 

 specimen 7, further development would have resulted. In other 

 words, it appears probable from the evidence here adduced that 

 not only is the gradual increase in size due to increased food supply 

 but the number and size of the macrochaetae increases almost 

 directly with the size of the individual. Correlated with this is 

 a gradually increasing brilliancy in color. The stunted specimens 

 are pale, the golden bands of the abdomen are faded and the 

 wings nearly hyaline, the squamae dirty white. At the other 

 extreme of size and chaetophorous development, the colors are 

 most brilliant, the bands of the abdomen are splendidly golden 

 in contrast with the remainder of the abdomen which is intensely 

 shining black, the eyes in life are purple and iridescent, the wings 

 and squamae are a very dark brown. Between these extremes 

 there is a gradation of color. It may be seen from the foregoing 



