34'2 THE ENTOMOLOGIST. 



A very striking example of this law is exhibited by the hybrid 

 of Deilephila euphorhia ^ x D. vespertilio ? . All the individuals of 

 this crossing which I have yet seen — about fifty specimens — are 

 so near to D. euphorbics that one would suppose that they were 

 an ill-characterized variation of the latter species, if its hybrid 

 extraction were not known. The type of D. euphorhm is distri- 

 buted over nearly the whole world in numerous species, and is 

 therefore almost certainly the relatively older ; whereas Z). ves- 

 pertilio is a solitary type of eccentric character, occurring over a 

 very limited area, and therefore most probably newly formed. 

 The reciprocal hybrids of Smerinthus ocellata x S. populi (both 

 forms are known) illustrate the law in question very thoroughly. 

 We have good grounds for believing that the type of S. populi is 

 older than S. ocellata. The highly differentiated eye-markings 

 on the hind wing indicate this fact very strongly. 



The cross between S. ocellata 3' x populi 'i is in colour and 

 markings nearer to S. populi than ocellata, and the reciprocal 

 cross S. populi $ and ocellata 2 exhibited among the specimens 

 hitherto seen by me, even a specimen which could not be dis- 

 tinguished from the very variable populi. 



Besides the evident predominance of the phylogenetically 

 more ancient p)opuli type- on the part of the hybrids, this 

 crossing showed another or second law very thoroughly, namely, 

 that the male sex has a far greater influence on the resulting 

 hybrids than the female. 



In the reciprocal crosses between Saturnia pavonia, L., x spini, 

 Schiff., of which S. spini, Schiff., is the more ancient type, the 

 case was the same ; the male element had more influence on the 

 resulting form of the hybrid than the female (see Handbuch, 1896, 

 pp. 66-76). The same fact has been noted by C. Oberthiir in 

 the third and last reciprocal hybrid as yet known (bred by 0. 

 Hiini-Inauen, Zurich); Biston hirtarius, G\. x p)omonarius, Hb., 

 hjhi.p)ils:ii, Stdf., from a pairing of hirtarius, CI., 3 x pomonarius, 

 Hb. ? (see Handbuch, 1896, pi. iii. figs. 1 and 2 ; and Oberth. 

 Bullet, de la Soc. Entom. de France, 1897, No. 15, pp. 256-259, 

 and pi. 1) ; hybr. hilnii, Oberth., from pomonarius 3 x hirtarius, 

 ? (see Bullet, de la Soc. Entom. de France, 1897, No. 15, pi. 2). 



Of the reciprocal crossing of two local races of the same 

 species, of which the author bred many examples, viz. : — 



1. Callimorpha dominulaS" X dominula var. persona, Hb., ? . 



2. C. dominula var. persona, Hb , $ X dominula, L., ? . 



3. Spilosoma mendica, CI., <y X mendica var. rustica, Hb., ? . 



4. S. mendica var. rustica, Hb., <3 x mendica, CL, ? — 



the reciprocal mixtures of C. dominida, L., and its var. persona, 

 Hb., fell under this law, but the reciprocal mixtures of the small 

 ermine {S. mendica and its var. rustica, Hb.) showed that the 

 hereditary qualities of the female individual were apparently in 



