SPILOSOMA MENDICA, ETC. 77 



the mongrel than the female. He also repeats, with confidence, 

 his previous opinion that var. rustica is the older race, that it 

 was generally distributed during the interglacial, desert period, and 

 that S. mendica arose later with the change of climate. Further, that 

 var. rustica in part assimilated itself with the changed conditions, and 

 in those localities, forming its present insulated area of distribution, 

 maintained itself by better adaptation, as proved by its occurrence in 

 Bergell, Roumania, Bucovina, the Caucasus — and I may add — in 

 Ireland. 



Where the two areas occupied by the type and the variety meet, 

 Mons. Caradja thinks the mongrel form standfussi iwwBi exist naturally 

 with the type and variety, since his crossing experiments prove that 

 the males of var. rustica, and the females oi mendica, procreate healthy 

 descendants. In the neighbouring Carpathian mountains, our observer 

 states that the type appears exclusively to occur, he having captured 

 it at an elevation of about 900 metres. In the Roumanian hills, at 

 30-40 kilometres distance, he had, until this spring, only caught 

 and bred males of var. rustica. He was, therefore, surprised, when he 

 found in the box — in which he had placed female mendica and stand- 

 fussi for the purpose of attracting wild males— besides 134 male 

 rustica, 14 specimens, of which part were identical with the form 

 standfussi, the other part with the form clara — without doubt, natural 

 mongrels. A third form (9 individuals), with darker bordered, milk- 

 white, or pale yellow-grey wing areas, was also taken. These, it will 

 be observed, are the reverse of the form mixta, and hence the name 

 inversa is proposed, and it is suggested that these have been developed 

 by the crossing of the form standfussi with var. rustica. This point 

 he hopes to clear up, with the emergence of the progeny of this year's 

 insects, which he is now experimenting upon. 



Mons. Caradja states that in the arid parts of Central France, 

 isolated cases of male mendica assuming a light grey colora- 

 tion, occur, which he looks upon as cases of reversion to the 

 form rustica, which also was probably the earliest form of the species 

 there. He believes that his facts point to var. rustica as a race under- 

 going extermination, and that its complete disappearance in the near 

 future is very probable. We prefer to look upon it as simply developing 

 over a greater area than hitherto into the form we now call mendica, 

 and have but little doubt that long after rustica has disappeared as a 

 variety or local race, it will exist as a recurrent aberration of the sup- 

 planting mendica, reverting to the original form. 



In conclusion, we are told that the in -breeding of these mongrel forms 

 has, so far as the pairing of (1) standfthssi males and females (14 

 pairings), (2) standfussi with mendica {^ and 5 ), and (3) standfussi 

 with rustica {$ and J ) (24 pairings), are concerned, produced in every 

 case fertile ova, yet it is remarkable that the pairing of rustica J with 

 mendica $- only very rarely results in the production of living larvae. 

 The observations of Mons. Caradja are of such interest that no 

 excuse is needed for bringing them before our readers. The fact that 

 var. rustica occurs in Ireland, that typical mendica is so generally 

 distributed with us, and that a few years ago quite an excitement 

 existed among our collectors who were breeding var. rustica, should 

 certainly cause our Irish lepidopterists to bestir themselves to get some 

 fresh stock, and when this is obtained, the previous experience of 



