42 THE entomologist's RECORD. 



We may add these up thus ; — 



First 4 lots to July 14 

 Next three lots to July 23 

 Remainder to August 21 



327 336 



These were dates, I may repeat, of counting, the mean dates of 

 spinning up would be about a week or ten days earlier. 



Though the moths look very different from 0. antiqua, and their 

 habits of egg-laying are very different, the larvae very much resemble 

 those of the " common vapourer." They have more brilliant red 

 tubercles and want the lateral tufts of hair, but are otherwise very 

 close. I was interested to discover whether the larvse had the curious 

 moulting discrepancy of 0. antiqua, in which species each brood may 

 be said to have two sets of larvae, one set having one more moult than 

 the other, and in each set the females one more moult than the 

 males. 



I carefully noted a very large number of iarvffi, chiefly by passing 

 them forward to another jar as they moulted, but I found that apart 

 from this each instar had such distinctive plumage that all the re- 

 mainder obviously confirmed the results of the more carefully noted' 

 sections. The result was that no larva spun up in the fourth instar, 

 but all did so in the fifth, with an interesting exception. Amongst 

 336 female larvaB that spun up all but 14 did so in the fifth instar, but 

 these 14 took another moult, that is, entered a sixth instar. These 

 grew decidedly larger than the others, but presented no difference in 

 plumage. 



This shows a very distinct constitution from that of 0. antiqua. My 

 recollection of the larva of 0. splendida is that they gave no indication 

 of variation in the number of moults, though I made no exact observa- 

 tions from the first stage onwards. 



The number of extra-moulters (in females only) amounted to 4% 

 of the female larvae, and may probably be regarded as being merely 

 ordinary variation as to moulting that occurs in so many species, 

 giving of course in all such species a basis for selection to such definite 

 specialities of moulting as occur in 0. antiqua and in Arctia caja, and 

 many others. I give this as my own view, though it might no doubt 

 be taken to be the remains, by regression, of such a habit as obtains in 

 0. antiqua. 



I may briefly note the plumage of the five several instars. In the 

 first the prothoracic projections are obvious, but there are no hair 

 tufts — full grown length 5-5mm. to 6-Omm. In the ^nd instar the 

 tufts are all represented, but so weakly that they have to be looked for, 

 and might on a superficial glance be regarded as absent — length full- 

 grown 7mm. to 9mm. In the third instar all the tufts are very obvious, 

 almost conspicuous. In the fourth the tufts are markedly larger than 

 in the third. The dorsal tufts are of a dirty white, darker certainly, 

 but all four are not of uniform tint. In the fifth (and last) instar the 

 tufts are all larger. 



The dorsal tufts are now all of the same coloration, pure white at 

 moult and may remain so, but generally get darker medially down the- 



