l36 THE entomologist's record. 



Loafs series did not seem to favouL' the opinion that had been held 

 that Teracolus eraf/ore, as described and figured by Kkig, was the dry- 

 season form of T. yerhnrii, Bwinh. It appeared from this and other 

 evidence that Mr. G. A. K. Marshall Avas right in dissociating the two 

 forms. The weakness of the reasons given for the contrary view had 

 lately been pointed out by Colonel Yerbury. With regard to the 

 general question of seasonal dimorphism, a point that deserved notice 

 was the greater intensity and greater persistence of the cryptic dry- 

 season coloration of the undersurface, which often characterises the 

 female sex. This might be illustrated from among Mr. Loafs speci- 

 mens, but the principle was of wide application, and was operative in 

 both hemispheres. In the genus Teracidna especially, the " wet- 

 season " female often retained some of the " dry-season " garb, and, in 

 certain cases (as in T. /iiidlaris and T. phisadia), the female could 

 scarcely be said to have a "wet-season" phase at all. The significance 

 of these facts lay no doubt in the special need for protection experienced 

 by the female sex. Professor Poulton had lately given strong grounds 

 for believing that, on the whole, concealment was a more efficacious 

 means of defence for moderately distasteful forms than the display of 

 warning colours, especially when the pursuit was keen, and the 

 instances here adduced seemed to show that it might, in some cases, be 

 of advantage for the female of a given species to remain cryptic in the 

 wet season, even though the male should assume brighter colours with 

 the advent of a more copious supply of insect life. An interesting 

 parallel with the seasonal changes in Precis a nt i li ipe SbXid P. archesia, so 

 carefully worked out by Mr. Marshall and Professor Poulton, was 

 furnished by the Central and South American Pi/yisitia proUrpia, 

 Fabr. (a Pierine allied to Terias), with what is doubtless its dry-season 

 phase, P. i/nndlachia, Poey. Here, as in I'recis, the dead -leaf appear- 

 ance of the undersurface in the dry-season form is enhanced by the 

 falcation of the forewings and the development of " tails." These 

 changes of shape are found in the (/inullac/iia form of both sexes, but 

 are intensified in the female ; in the wet-season or piatcipia form they 

 are retained by neither sex, but the undersurface of the female is duller 

 than that of the male. The simultaneous occurrence in generally dry 

 localities, such as Aden, of forms which, in other places, are associated 

 with contrasting seasons, was not easy to explain. Professor Poulton 

 had shown that, in several species of Precis, the dry-season form was 

 larger than the wet, and had, on that fact, founded the inference that 

 the dry-season form must have been predetermined in the larval stage. 

 But there was reason to believe that, in many genera, and perhaps even 

 occasionally in Precis, the assumption of the characteristic seasonal 

 garb was not determined until a later period — in some cases, the last 

 few days before emergence from the pupa. If it might be assumed 

 that the Aden species in question were in a state so sensitive to 

 meteorological conditions as to respond almost immediately to a few 

 heavy showers, such as were reported to fall there not unusually from 

 January to May, the intermixture of " wet-" and " diy-season," which 

 in many cases meant an intermixture of aposematic and cryptic, forms, 

 might possibly be accounted for. This suggestion could only be 

 verified by observers on the spot. 



At the same meeting Mr. Lucas exhibited with the lantern 

 a series of slides illustrating the life-history of Liphyra hrassolis, 



