TERACOLUS. 85 



sci/heri, one of its food-plants. Most of my larvse of C. keiskamma were procured by 

 beating, as it was most difficult to detect them on the shrub. In raising chrysalids I 

 was particularly struck by the variations of their colour under different conditions. 

 These variations were not, however, followed by any marked differences in the colour 

 and form of the imagines. 



"About this time I regret to say that I gave away most of my specimens of this 

 species to a INTr. Bailey, of Port Elizabeth, under the impression that I could at any 

 time replace them, and being engaged in some other work, I neglected to collect this 

 species until the end of 1876. To my great surprise, I found every insect captured 

 on the bush proved to be not C. keiskamina, but C. evanic, which I had also not noted 

 in the neighbourhood before. Owing to the dryness of the season, these, however, 

 were scarce, and it was some time before I had an opportunity of watching the females 

 ^aying their eggs or of collecting the larvae. By daily watching the bush I had, 

 before leaving in April last, succeeded in collecting several, which were exactly similar 

 to the larvse obtained in the previous autumn. I also saw the female C. evanie 

 laying her eggs in precisely the same manner as did the female of C. keiskamma. 'J'he 

 eggs in like manner did not differ ; and not merely were the pupee the same in shape 

 and markings, but they presented the same liability to vary in colour as did those 

 of C. kehkcminia. 



" Up to the end of April last I never saw another specimen of C. keiskamma, 

 although the specimens of C. evanie round the bush in question were numerous. I 

 think this a most curious case, because, although the two insects closely resemble 

 each other, the differences relate not merely to the colour of both wings on both 

 surfaces and in both sexes, but also to form. 



" Considering how closely many of the so-called species of this group resemble 

 each other, and how extremely variable are even the forms collected in a single locality, 

 1 think that an instance such as this should make naturalists pause before multiply- 

 ing its nomenclature. Although I am disposed to think that more careful observation 

 will show tliat this is not an isolated instance in the Fierina group, it certainly would 

 seem contradictory to the axiom ' Natura non facit saltum.' 



" I may remark that individuals of both forms vary much, but in none of the 

 instances collected by me do they show any tendency to vary in the direction of the 

 other form. 



" From what I have noticed in some other Ficric/a, I am inclined to think that the 

 yellow coloration to which some species are peculiarly subject depends in some way 

 or other on the dryness of the season. Specimens of P. severina and /'. wrsentina 

 (females) collected in dry seasons in moist localities or in dry districts are genenllly 

 deeply colom-ed. 



"N 



