14H 



\iir\e\\ oi' forui^dta, niid a good example of inelniiism, as it occurs only in 

 Northern Europe, and none have yet occurred in Ihe Southern United States 

 south of Massachusetts, though our knowledge of the distribution of this 

 species in America is exceedingly imperfect. 



Th(! localities of ferrugarla (not including unklentaria), given by Stau- 

 dhiger, are as follows: Europe (excluding Andalusia, Sardinia, and Greece); 

 Bithinia; Altai Mountains; and Amur. 



f^ftrni. — "The eugs are gen<'rally laid on the stems of grouud-ivy (G/c- 

 choiiia Iiedcfdrea), on the leaves of which plnut the caterpillars feed. The 

 i)cri()d in the egg-state varies li-om leu to twenty days, according to the tem- 

 pei-ature; the cold east winds, which so freciuently prevail in the spring, 

 <n-eatly retarding their euiergence. The full-fed caterpillar rests with the 

 anterior extremity rigidly extended, iiut often in a slightly-arched position. 

 When auno3e(l, it lucks In its head, and rolls up tln^ anterior part of its body 

 in the form of tlie Ionic volute. The legs are crowded together and closely 

 appresscd to the mouth; the iu'ad is prone, not conspicuously notched on the 

 crown, and nearly of the same width as the l)ody ; the l)ody is of nearly the 

 same width throughout, and mf.forndy cylindrical, with the exception of a 

 lateral skin-fold, which extends its whole length ; it is without humi)s, but, in 

 connnon \\ith the head, has a few small scattered warts, each of which emits 

 a single small bristle; the head is putty-colored, freckled with black on the 

 liice, and luiving a darker stripe on each cheek; the color of the dorsal area 

 of the body, as l:u- as the ninth segment, is dingy-brown, but this hue appears 

 to l)e caused l)y the somewhat tessellated ornamentation ; this consists, in the 

 lirst place, of a nn-dio-dorsal stripe, narrow and almost thread-like, <m the 

 third, fourt It, tilth, tenth, eleventh, and twelfth segments; on the sixth, sev- 

 enth, eighth, and ninth segments, the medio-dorsal stri|)e is interrupted, and 

 i-(!duce(l to a median, intensely black, spot; each of these l>lack spots is sur- 

 rounded by a paler area, dilated laterally, but attenuated at Ihe extremities; 

 a dorsal seiies of lozenge-shaped markings results as far as regards these four 

 segments; on ea(;h side of this dorsal ornamentation are three slendcn- rivulet 

 stripes, all of them sesqnialterons or semi-donble, but neither of them very 

 conspicuous; the ventral area, extending to and including- the s[)iracles, is 

 putty-colored, but the spiracles lliemselves are intensely black, and surrounded 

 l)y a paler area ; there is a medio-ventral, pale-brown, or reddish stripe, con- 

 taining three l)lack spots, and extending from the liflh to thelwellth segment; 



