Tin: Kdd: KXTERXAL (IIAItACTKKISTICS. 3 



These eggs, though al\v;iy,s circular or round!}' polyhedral* in .section, 

 vary greatly in shajR', and are clatised in one of the chapters of this work 

 mto barrel-shaped, globular, tiarate and hemispherical. The first are the 

 most eonnnon, vary nuich in [)roportionate lieight and are usually also 

 ribbed vertically, the ribs varying in our species from eight to thirty or 

 forty in number, the former obtaining in some species of Vanessidi, the 

 latter in Kiu-ema. AMiere the ribs run from base to summit, the si)ace 

 between them is always broken u[) into (piadrate cells, by nuich more fre- 

 (pient and generally more delicate raised transverse lines. But the character 

 of the ribs v aries in ditl'erent species almost as nuicli as the form of the egg 

 itself ; and while some of these eggs are two and a half times higher than 

 broad, the lieight of others exceeds their breadth by very little ; some are 

 thimble-shaped, sugar loaf-, flask- or acorn-shaped, while others are even 

 fusiform ; so the ribs may either be coarse and heavy, or delicate, strongly 

 compressed and greatly elevated ; tliev may be as large at their edges as at 

 their bases, or wedge-shaped ; the cross lines are usually very delicate, but 

 in a few species they vie with the vertical ribs in stoutness and near or upon 

 the sununit of the egg are often nuicli heavier than elsewhere. Barrel- 

 shaped eggs occur in every family excepting the Lycaenidae. 



Globular eggs occur only in the Satyrinae, Nymphalidi, and Papilion- 

 inae. They are always a little flattened at the base. The surface is either 

 simply rugose, as in the Papilioninae ; or covered with veiy minute and 

 very inconspicuous cells, as in some Satyrinae ; or is l^roken up, as in Xym- 

 phalidi, by very high and thin partition-walls into pretty regidar deep 

 hexagonal cells, from the angles of which thread-like filaments project to a 

 considerable distance. 



Hemis[)herical eggs are only known in the Pamphilidi, and among them 

 we find great uniformity. The surface, apparently smooth, is broken up by 

 exceedingly delicate lines into minute, usually hexagonal cells, the floor of 

 which is profusely filled with shallow microscopic punctulations. 



AVith the sole exception of the genus Paruassius among Papilionidae, 

 not found in eastern America, tiarate or echinoid eggs are confined to and 

 include all of the Lycaenidae, but in one genus, Heodes, the base of the 

 egg is broadened to such an extent that it is only by suflferance that it can 

 be classed here ; it is rather demiechinoid ; the surface of tiarate eggs is 

 nearly always broken up into cells of varying size separated by distinct 

 heavy walls, which are sometimes of uniform height throughout, at others 

 produced at the angles into tubercles presenting on close examination a very 

 different effect. 



The egg shell, without taking into account the increased thickness which 

 is often given to a large part of the svu'face by ridges and ribs, is always 



*I)oberty snys that in the East Iiulian Ly- probal)lymeansi simply that the cells arc oxcesi- 

 caeuid, Poritia, the egg is hexahedral, which sively large .ind few. 



