212 [August, 



ON OVIPOSITION, AND THE OVIPOSITOR, IN CERTAIN 

 LEPIDOPTERA 



BY JOHN H. WOOD, M.B. 

 {continued from page 185). 



AVe now come to that most interesting class, the plant-cutters. 

 In addition to JSIicroptcryx and Incurvnria, the genera Lamprojiia, 

 Adda, and Nemo-pliora must also be included, as well as, judging from 

 dry specimens, Ncmotois, Pancalia, and Tinagvia, which, perhaps, 

 exhausts the list, so far as the British fauna is concerned. In those 

 that pierce the seed-pods of their food-plants and lay their eggs among 

 the seeds, like Adela riifimitrella and Jibulella, the end of the instru- 

 ment is conical, but hollowed out on the under-side, and may be 

 likened to the mandible of a bird's beak. In A. viridella it is shorter, 

 and more trowel-shaped, and has the visceral tube ending immediately 

 behind it in a pair of large, singular looking flaps. The use and 

 meaning of the apparatus must have remained unsolved but for a 

 valuable observation made by Dr. Chapman. Having placed two 

 moths on some fresh sprays of oak, he found that five eggs had been 

 inserted by their narrow end into the tender petiole of a baby acorn, 

 and were sticking half in and half out of it. We may, therefore, 

 suppose that the trowel gouges in some tender stalk or stem (perhaps, 

 not necessarily, a flower stalk) a shallow cavity, into which the point 

 of the egg is guided by the flaps of the visceral tube. Nemophora 

 ScliwarzieUa has a very similar instrument, and she probably sticks her 

 egg half in and half out of some similar part of her food-plant, 

 whatever that may be. Lampronia prcelatella and rubiella, on the 

 other hand, have broad, chisel-like instruments, with the cutting edge 

 curiously indented and scolloped according to the species, and without 

 any flaps to the visceral tube. They are for cutting through the 

 receptacles of flowers and depositing the egg in the loose cellular 

 tissue within. Here, again, I am indebted to Dr. Chapman. I had 

 suggested that rul it! la would probably lay in the flowers of raspberry, 

 and my friend has actually watched her perform the act. She sits on 

 the open flower, thrusts the point of her body in among the outside 

 stamens, and in about two and half minutes manages to pierce the 

 receptacle and lay her egg. PrcBlatella will almost certainly be found 

 to lay in a similar way in some other flower. 



As these various instruments are all very much alike, it makes very little 

 difference which we select for illustration. Let us take, then, Adela viridella. 



In the first place it is well to notice the great strength of the abdominal 



