THE YOUNG NATURALIST. 



61 



starved. Mr. Gregson attributes his suc- 

 cesses in getting good varieties of A . grossu- 

 lariata to the constant introduction of larvae 

 from other places among the colony he 

 keeps in his garden. On the other hand, I 

 know of a collector who for several years 

 bred a very fine form of L. dispar without 

 any crossing at all. Though I have occa- 

 sionally reared an abnormal form of various 

 species, I have never been successful but 

 once, in breeding varieties when I tried to 

 do so, and an account of the process may be 

 interesting. I had been reading " The 

 Naturalist on the Amazon" and was much 

 struck by the account given of certain but- 

 terflies which varied so much when frequent- 

 ing damp woods, from those occurring in drier 

 and more open places, that they had been 

 thought distinct, till Mr. Bates found the 

 intermediate forms in localities of interme- 

 diate character. It occurred to me that I 

 might try to imitate the damp close woods, 

 of the banks of the Amazon, and might thus 

 succeed in getting good varieties. I procured 

 thirty very young larvae of ^. caja, which I 

 selected because they were very hardy and 

 very subject to variation. I took a large 

 glass jar, such as is used by confectioners, 

 and half filled it with sand. This sand I 

 ; made quite wet, or perhaps, very damp would 

 be a better term. I covered the jar with 

 paper slightly perforated and tied it tightly 

 down. This, with the larva; in it, I placed 

 I in the sun during the day, and when the sun 

 I was not shining I kept it on the hearth 

 where the heat of the fire would fall upon 

 it, but not near enough to scorch. For food 

 I gave them chiefly groundsell, but occa- 

 sionally a little lettuce. The treatment was 

 evidently too severe, for out of my thirty 

 larvae only six pupated. When they emerged 

 they were all well marked varieties. One 

 was a very peculiar one, and is figured in 

 Mosley's illustrations, plate 6, fig. 4. Five 

 of them were considerably darker than the 

 normal form, but the sixth was the lightest 



j specimen I have yet obtained. Encouraged 

 I by this success, I tried the same experiment 

 j again "for two or three years, but utterly 

 I failed. Whether I kept them too damp, too 

 warm, or gave them too little air, I don't 

 ' knew, but I never got another imago. The 

 experiment, therefore, though apparently 

 successful, really proves nothing, and I pub- 

 lish it here with the idea that some one else 

 may try the same, or some modification of it. 



It has often been wondered that with so 

 variable a species as the Tiger, no well- 

 marked form has ever established itself, 

 but the very tendency to vary will prevent 

 any particular form from becoming estab- 

 lished. I am strongly inclined to believe 

 that if any one would breed from his darkest 

 or lightest specimens, for a few years, he 

 would be successful in producing extreme 

 forms. I have noticed, however (and I do 

 not remember if the fact has been published 

 before), that among the insects that die 

 without emerging, there are always a number 

 of good varieties, as may be seen by peeling 

 the pupa case off the wings. 



BRITISH MOTHS: 



By John E. Robson, 

 (Assisted by Contributors to the Y.N.) 



Though it is not intended that the species 

 shall succeed each other in scientific order 

 in the following papers, it is nevertheless 

 desirable to give a brief account of the 

 various groups into which the large number 

 of insects known as Moths, or in science 

 Heterocera, are arranged. It is not to be 

 wondered that among such a vast assemblage 

 of species, and where there is such great 

 diversity of form and habit, as we find 

 among the moths, that there has been con- 

 siderable difference of opinion as to the 

 number of groups into which they ought to 

 be divided, and also as to which group cer- 

 tain species or genera belong. Nor can it 

 be expected that strict definitions can be 



