72 LEAF-MINING INSECTS 



alike in venation, remote from one another at the base, and 

 semi-oval in shape and that the fore wings are marbled or 

 reticulated. 



FAMILY ERIOCRANIIDAE 



The leaf-mining members of the Lepidopterous suborder 

 Jugatae are but a few species comprising the small family 

 Eriocraniidae. Eriocrania auricyanea, has been carefully 

 studied by August Busck (1914), who describes the adult as 

 "a small (expanse 12 to 14 mm.) strongly iridescent golden 

 bronze moth, sprinkled with scintillating, bright metallic 

 purple scales." European species were studied earlier in 

 England by Chapman (1900). The following account is 

 mainly based on the work of these two authors. 



Eggs. The rounded cylindrical eggs are placed in a pocket, 

 cut in the tissue of a leaf by a serrated, lancet-like implement 

 in the abdomen of the female. J. H. Wood describes the 

 process for the European Eriocrania semipurpurella. The 

 adult, he says, selected a "forward bush" of birch (Betula 

 alba) just coming into leaf. She examined a bud with her 

 maxillary palpi and finding it to her liking took a lengthwise 

 position on a leaf. She then curved her abdomen and 

 inserted the points between the folds. After a series of 

 rocking and thrusting movements, with intervals of rest, 

 the ovipositor was withdrawn. Going to other buds she 

 made one laying in each. If the temperature was "warm" 

 a laying took two and one-half minutes, if "cold" four 

 minutes. Examination of the leaf made apparent a small 

 incision on the underside which led to a deepish chamber 

 with an egg in the bottom. Dr. T. A. Chapman observed 

 the process in Eriocrania purpuriella. This species sits 

 across the leaf and pierces it on the edge of a lateral rib. 

 Her pocket is wider and shallower and usually contains 

 three eggs. In "cold weather" it sometimes took her fifteen 

 minutes to make a laying. According to Busck and Boving 



