Insects. 6867 



gation. I give the following as some of the results. Having prefaced these remarks 

 with a description of the larva of H. abruplaria, I will commence with that insect. 

 My friend Mr. Crewe, at the beginning oflast summer, sent me about a dozen and a 

 half nearly full-fed larvae of this species, with a request that I would take care of ihem, 

 as he was leaving home for a lour in Scotland. They fed up tolerably well, and in 

 due course went down. After the lapse of a month a crippled female appeared, and 

 was followed, three days later, by a crippled male. Having kept the female alive, I 

 obtained from this pair of cripples a dozen eggs. The rest of the brood from which 

 these two came are still (January) in the pupa state. The dozen eggs hatched almost 

 immediately ; the young larvge, however, feeding so slowly that I at once suspected 

 they were going to bother me by hyberuating. When about one-third fed I showed 

 them to Mr. Crewe, who paid me a flying visit on his return from Scotland. In spite 

 of blandishments, such as juicy food and plenty of it, to persuade them to feed up 

 and have done with it, ihey turned sulky, and exercised a doubtless praiseworthy 

 moderation, continuing, day after day, to nibble at their food (privet) throughout the 

 winter. They are now nearly full-fed, but show no signs of going down ; and every 

 time I remove the gauze cover I find them rigidly extended, with a resolution, I 

 would venture to say, worthy a better cause. It is from these I have taken my 

 description. Now, from the circumstance of these two crippled specimens having 

 emerged from the pupae in the autumn, do 1 infer that H. abruptaria is a double- 

 brooded insect .'* Certainly not, at least in the sense in which I understand the term. 

 To prove it double-biooded (strictly) alt should have become perfect insects. Had 

 they done so I should have saxd, prim d facie, it was a double-brooded insect. But, 

 even so, T should not have been quite satisfied. I should continue the investigation 

 for two or three seasons longer ; and if I then found that it was the invariable custom 

 for all the pupae to produce insects in the autumn, I should unhesitatingly pronounce 

 it a strictly double-brooded species. If, on the contrary, I found a very small mino- 

 rity only coming to maturity, the remainder passing through the winter as pupae, and 

 if I found this to be the rule, I should just as unhesitatingly say that the insect was — 

 anything you like, except double-brooded. The next example I shall adduce is that 

 ofP. palpina. A number of larvae, recently hatched, were sent to me, at the same 

 time as those above-named, by Mr. Crewe. These fed extremely well, and all went 

 down, in number I suppose about thirty. One single insect, a male, appeared about 

 three weeks afterwards. This specimen I showed to Mr. Crewe. All the others are 

 still in pupa. A precisely similar circumstance occurred in 1858, in reference lo 

 N, ziczac. I found about sixteen eggs of this species in June. In due time they 

 hatched, fed and spun up, or went down, whichever is the best term. In this case 

 also one insect, and one only, a male, emerged the same year. The last instance I 

 shall bring forward is that of S. conspicuaria. In the autumn of 1858 Mr. Crewe gave 

 me six pupae of this insect. These all produced perfect insects the following May. 

 From these I obtained eggs, as I was anxious to perpetuate the species, and, if pos- 

 sible, introduce it into the county. In this latter eflForl I fear I have failed, much to 

 the satisfaction of some I have no doubt. The larvae hatched from these eggs fed up 

 very rapidly, and went down, in number about fifty-six. Greatly to my surprise, and 

 I may add pleasure, three weeks later one male and two females appeared in the per- 

 fect state. From these, again, I obtained a batch of eggs. With equal rapidity these 

 fed up and went down ; and both sets of pupae are now in statu quo. Once again I 

 ask, am I to infer from this fact that S. conspicuaria is double-brooded in the strict 



