2()6 Mr. Horace A. Byatt on 



As this rare monstrosity was found among the large 

 number of specimens tabulated by Mr. H. A. Byatt it 

 was thought well to select it for representation, inasmuch 

 as the teratological interest is simply an additional 

 advantage which in no way interferes with the bionomic 

 interest of the plate. 



The subapical white bar on the fore-wing of chrysippus 

 is prolonged downwards and outwards with a slight in- 

 ward trend by means of a few small marginal spots and a 

 local intensification of the white elements in the fringe. 

 This character is very persistent, and is traceable in the 

 dorippus form when the band itself has, except for its 

 costal end, disappeared (compare Fig. 4 with 1). A similar 

 effect is produced in the $ misippus (Fig. 2) by the 

 position of the last or fifth spot of the band, by a local 

 strengthening of the two rows of whitish hind-marginal 

 lunules, and by the white elements of the fringe. The 

 three narrow interrupted white lines which are thus 

 formed parallel with the hind-margin, persist in the 

 inaria form when the band itself is only faintly trace- 

 able (compare Fig. 5 with 2). In both chrysippus and 

 misippus, it is obvious, especially in the latter, that this 

 prominent subapical marking is in large part prolonged by 

 the local strengthening or the local persistence of elements 

 which are not part of the bar itself, but belong to the 

 category of marginal markings. In this respect Pseuda- 

 crxa poggei (Fig. 3) stands in considerable contrast with 

 the other two members of the group; for its bar is 

 prolonged — and much more fully prolonged than in the 

 other species — by elements Avhich have the appearance of 

 continuity with the bar itself. If these elements are 

 marginal markings as in clirysippus and misippus they 

 have been far more subordinated to the subapical bar 

 than in these species. The local strengthening of white 

 elements in the fringe is also somewhat less marked, and 

 plays a less important part in poggei than in the others. 

 As regards the few minute spots at the extreme apex 

 of the fore-wing of chrysipptcs, mimetic resemblance is 

 more honoured in the breach by poggei than in the too 

 emphasized observance by misippus £ — to say nothing of 

 the very different position of the marking in model and 

 mimic. 



In spite of all these differences in detail, the two 

 mimics are by no means unlike; and in general effect 



