THJ; Lii'E-UiSTokY OF A LEpiD0i'*fEk0US iNHECf. 141 



the apex, surrounded by a pale zone, and the rest of the egg is finely 

 dotted with yellow or orange dots, on a reddish-brown base ; this 

 colouring is assumed in two days in warm weather, but in cool weather 

 the change occiipies not less tlian a week. Coming to Cmjiidin, the egg 

 of C. tridcns is nearly colourless, almost glassy, when first laid, but 

 ac(|uires a certain whitish opalescence as the larval development })ro- 

 ceeds ; that of C. ps/ is very similar. That of C. uini is, when first laid, 

 nearly as colourless as the two preceding, but soon assumes some 

 coloration, and in about three days reaches its proper tint, which 

 is colourless on the margin but within of a rich chocolate-brown, 

 marked with creamy- white nearly circular patches, which tend to be 

 arranged in two circles, round a central one ; for twenty-four hours 

 before hatching, the egg becomes much darker, with the black head of 

 the larva occupying the summit. The egg of C. megacephala when first 

 laid, is of a pale greenish colour, uniform throughout ; when fully 

 matured in colour, the colourless margin, due to the shrinking of the 

 inner egg, is wider than in any other species ; the inner egg presents a 

 series of brown spots, which are not round, but angular, usually 2)enta- 

 gonal, and Avhich differ in size in different specimens, being sometimes 

 mere dots, and at others so large, as to occupy nearly as large an area 

 as do the pale spots in C. ahii. In C. striijosa, the inner egg shrinks 

 away from the outer, leaving a clear margin, but as the inner egg re- 

 mains colourless, the margin is not so evident as in the coloured species. 

 In C. leporina, the egg, of a pale straw colour at first, develops a 

 cliocolate dot at the apex, surrounded by a small circular reddish jjatch 

 which is gradually invaded by the chocolate colour ; then round the 

 margin of the inner egg appear five to eight reddish sjjots, towards 

 which the chocolate area extends angularly, leaving for a brief interval 

 a circle of pale blotches between them ; finally, the dark colour sjJi'eads 

 over the whole of the inner egg. The egg of C. aceris, when first laid, 

 looks very like that of C. pd or C. trklens, but is a little more opaque ; 

 as the inner egg shrinks and leaves a colourless margin, it assumes a 

 rich chocolate colour, with pale straw-coloured spots, which often 

 coalesce and form streaks and blotches. In Bisxdcia ligustri, the egg is 

 of a pale pearly green, almost colourless, and very translucent ; the 

 inner egg shrinks from tlie cell, but does not undergo any coloration. 

 In Moma orion the egg is extremely delicate and transparent ; it acquires 

 a pale sti-aw tint, but no deeper coloration nor markings ; nor does any 

 change occur as the contained larva l)ecomes ready to hatcli, except a 

 slight increase of opacity, the young larva itself being very transparent. 

 The colour of the egg of Demas corijli, is pale greenish when laid, and 

 then becomes yellowish, with a circle of small red dots just above the 

 widest part. 



d. Ornamentation. — The number of the ribs with whicli lepidopterous 

 eggs are frequently ornamented, often varies very considerably. Dr. 

 Cliapman re})orts that as a rule the egg of Vanessa pohjchloros has eight, 

 but that in a small projjortiou there are only seven ; also, that of thirty 

 eggs laid on the same day by GrapAa c-albnm, thirteen had ten, and 

 seventeen eleven ribs. Edwards, writing of the closely allied species 

 Grapta interrogationis, which, like G. c-albnm, lays its eggs in little 

 columns, five or six eggs being placed on each other, says that the number 

 of ribs does not vary in the same column, but that the number of ribs 

 which is commonly ten, may be sometimes eleven. He thinks it probable 



