Quail. — On New Zealand Lepidoprera. 227 



a tree. Later on she caused an assembly of the opposite sex 

 of her species, and as they hurried up we could see their 

 little eyes glow in the darkness quite a distance away. They 

 would, fly straight to the cage and crawl all over the gauze 

 sides, and the light from our lantern did not scare them. As 

 they flew up we netted them, until quite a number of males 

 had been taken ; and when the flight was over one was let 

 into the cage, when it immediately copulated and fertile ova 

 resulted. The captured males were handed over to the other 

 entomologists present. 



For the purpose of embryology and of classification it is 

 necessary to describe the pattern of the ovum, the structure 

 of the larva and pupa. Although we may not know the why or 

 the wherefore, there must be some functional, constitutional, 

 or environmental reason for such structures. Without further 

 preface I will now offer for your consideration such observa- 

 tions on some species of New Zealand Lepidoptera as my 

 limited time has permitted. 



A Contribution to the Life-history of Metacrias (Meyr.) 



strategica (Hdsn.). 



For my material I am indebted to Mr. George Howes, who 

 recorded the occurrence of this species at Invercargill.* The 

 apterous female of this and of the two congeneric species 

 raises the interesting problem of the cause of such a condi- 

 tion. The Arctid genus Ocnogyna, of Europe, has females 

 with rudimentary wings, but I know of no others in the group. 

 Liparidce, which by derivation must have more or less remote 

 affinities with Arctids, have some completely apterous females, 

 some with rudimentary wings. Other groups of Lepidoptera 

 not associated with these exhibit the same phenomena. 

 Such must be considered specialised, and the apterous condi- 

 tion of the female is intimately associated with reproduction. 

 Lessen productivity and the species is nearer extinction. 

 Whether specialisation of the ovum and its chemical contents 

 is the great factor in reduction of productivity can hardly be 

 proved, but I am inclined to think it is so. The organism, 

 after exclusion from the egg, builds up physiologically from 

 matter assimilated as food ; but before exclusion from the egg 

 the organism is formed entirelv from matter contained within 

 the egg, derived wholly from the female parent (granted 

 seminal stimulus of the male) by the primary unicellular 

 germ using up surrounding cells in the ovary of the parent 

 until the ovum developed. This, at least, is as I understand 

 the process. The quantity of cellular matter absorbed per 

 ovum would affect the quantity of ova resulting; specialisation 



* Trans. N.Z. Inst., vol. xxxiii. 



