( exii =) 
specimens, including the type, both females, have hitherto been 
known to science. 
Mr. Loat’s series did not seem to favour the opinion that 
had been held that Teracolus evagore, as described and figured 
by Klug, was the dry-season form of 7) yerburti, Swinh. It 
appeared from this and other evidence that Mr. G. A. K. 
Marshall was right in dissociating the two forms. ‘The weak- 
ness of the reasons given for the contrary view had lately been 
pointed out by Col. 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 
under-surface, which often characterizes the female sex. This 
might be illustrated from among Mr. Loat’s specimens ; but 
the principle was of wide application, and was operative in 
both hemispheres. In the genus Zeracolus especially, the 
‘‘ wet-season ” female often retained some of the ‘“ dry-season ” 
garb, and in certain cases (as in 7’. pwellaris and 7’. 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. 
Prof. 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 antilope and P. archesia, so carefully worked 
out by Mr. Marshall and Prof. Poulton, was furnished by the 
Central and South-American Pyrisitia proterpia, Fabr. (a 
Pierine form allied to 7erias), with what is doubtless its dry- 
season phase, ?. gundlachia, Poey. Here, as in Precis, the 
dead-leaf appearance of the under-surface in the dry-season 
form is enhanced by the faleation of the forewings and the 
development of “tails.” These changes of shape are found 
in the gundlachia form of both sexes, but are intensified in 
