68 lepidoptera. 



Concluding Remarks. 



As a result of the preceding circumstantial observatiou5 

 (continued during many years) on the Sciaphilce., I would 

 suggest that the Wahlbomiana-gYOU]), as it can scarcely be 

 rightly considered as composed of one sj^ecies (Heinemann, 

 vol. ii. p. 58), appears to afford a very good illustration of 

 the Darwinian views, according to which the tendency to 

 variation in a species first leads to the formation of constant 

 varieties, and gradually to their separation into distinct 

 species. Sc. communana and virgaureana, which, in the 

 larval state, show constant differences from the typical species, 

 whilst in the perfect state, as Heinemann specially maintains, 

 and rightly so, and as I have myself frequently observed, 

 one can find numerous transitional forms to the typical species; 

 and they can, therefore, only be reckoned as varieties of it, 

 whilst Sc. Ttiinusculana with its var. incertayia^ in which an 

 essential departure from the type in the form of the female 

 genital organs is observable, may rightly enough be con- 

 sidered as a distinct species. 



How it really stands with var. alticolana and derivana, I 

 cannot for want of observations of the larvae determine; yet 

 they would also appear, especially alticolana^ to which forms 

 very similar occur amongst the Wahlbomiana of the plains, 

 on that account, and on account of the similar formation of 

 the ovipositor, only to be varieties. 



Further, it seems to follow from my observations that 

 certain differences from the type first become perceptible in 

 the larva state, and gradually become constant, whilst up to 

 such a time no perceptible differences have been developed 

 in the perfect insects, and in the unicolorous group of the 

 genus Coleophora I have observed a very similar state of 

 affairs. 



