1892.] 21 



families (?'. e., offspring of a single pair) of the spring feeding larvae of Selenia 

 illustraria {tetralunaria) , the individuals of each family averaging perhaps 50 or 60 

 in number. These have invariably (barring an occasional straggler which has fed 

 slowly and gone over till spring) emerged as moths the same summer, with the ex- 

 ception of four families that (barring two individuals which emerged the same 

 summer) went over till the next spring. The families (40 in number, or thereabouts) 

 which followed the normal course were reared on trees in the open air ; the four 

 exceptional families were brought up on cut food indoors. There w^as doubtless a 

 substantial difference in the temperature between the two classes, probably not less 

 than 5 or 6 degrees, F. ; but a higher temperature being, as is well known, a cause 

 which promotes double-broodedness, the operation of this would be in the opposite 

 direction to that of deferring emergence till next spring ; and in fact some of these 

 four families pupated rather earlier than those which were sleeved. Some other 

 cause than temperature must, therefore, be sought for. I have mentioned that each 

 of the four families was fed on cut food. Further, I have ascertained that in the 

 case of one the larvae were kept in an open wooden or cardboard box, and fed with 

 twigs simply laid in the box, and that the other three families of larvae were fed in 

 large plum-bottles on food not standing in water, and further, that these plum-bottles 

 stood away from draughts of air, and, in fact, that moisture was rarely observed on 

 the glass. These circumstances seem to me to point to the different condition of the 

 food plant, as regards the circulation of sap and internal dryness, as the probable 

 cause of the difference in the behaviour of the larvae. In a state of nature the 

 autumn larva, which is destined to emerge in the spring, feeds during the latter part 

 of August, September and October, on leaves in which little sap is circulating ; in 

 this respect the condition of its food- plant must bear some resemblance to that of 

 the cut food under the circumstances I have described. 



Of course the cases of S. fagi mentioned by Mr. Holland are in several respects 

 different ; for example, that species is only exceptionally double-brooded, whereas 

 S. illustraria is so normally. Still, in the case of S.fagi the statement is that it is 

 those fed indoors which are not emerging as a second brood, while some of those 

 " fed under natural conditions," i. e., on growing food, are so emerging ; and there- 

 fore, it would seem not improbable that the former have been fed on more sapless 

 food, and that may be the reason why they are all " going over" till next spring, 



Brighton : December, 1891. 



CallimorpTia Hera.— I see by a Eeport of the Entomological Society's Meeting 

 of November 4th, that a discussion took place as to the manner in which Calli- 

 morpha Hera had been introduced into England. Thinking it would be of interest 

 to you, I enclose a copy of a statement made by the late Dr. F. C. Lukis in a 

 Guernsey Guide Book, published in 1863.— W. A. Luff, 7, Mount Eow, Guernsey : 

 December, 1891. 



[Extract from Le Lievre's Guernsey Guide, 1863, p. 166.—" Now referring to 

 the CalUmorpha Hera, we think it due to science and to ourselves to give the 

 following account :— This is a most lovely moth, but enjoying the unenviable 

 soubriquet of the " Guernsey Tiger," although met with in nearly all the other 



