142 tUE entomologist's RECOtlb. 



that the number of ribs is the same for all the eggs laid by one individual. 

 This, however, in the light of Dr. Chapman's observation, is improbable. 

 Mrs. Peart made an observation on the same s^^ecies, in which she found 

 that the final egg of a chain had eleven ribs, while all the others had 

 nine. Scudder says the number varies from eight to eleven. In the 

 various species of Acronycta, it would appear, from Dr. Chapman's ob- 

 servations, that there is no constancy in the number of ribs. In V. 

 auricoma, it varies from 57 to 60, in V. venosa, from 41 to 45 ; in Cus- 

 pidia tridens, the average number is 38, and there are rarely more than 

 44, whilst in C. psi, the number is rarely fewer than 45, and some 

 specimens have as many as 54 ; Dr. Chaj^man, however, met with a case 

 in which the eggs of C. tridens had from 40 to 52 ribs ; these were laid 

 by a very dark moth, and produced large and dark imagines, so that 

 Dr. Chapman thinks that there may be two distinct races of C. tridens. 

 The eggs of C. leporina are very variable in the number of ribs, two 

 specimens having respectively 41 and 63, but the lesser numbers are 

 the more common. In C. aceris there are usually 70 to 75, but some- 

 times as few as 50. 



3. — On eggs as helping to ueterjiine natural affinities. — The 

 eggs of Lepidoptera are now much more generally taken into account in 

 attempting to determine the natural position of species. It has been 

 made a great point of by Dr. Chapman, in his researches into the affi- 

 nity of JDemas coryli, Biloha caerideocephala, and others {Ent. Rec, 

 vol. iii., pp. 249, et. seq.). Anent this Dr. Buchanan White writes 

 (E. M. M., vol. vii., pp. 230-1) : — " Lepidopterologists are not, as a rule, 

 guilty of laying too much stress upon little things ; indeed, it may be 

 said with truth, that they have altogether neglected to avail themselves 

 of almost any characters but those afforded by colour of wings, streaks, 

 spots, &c. It thus happens, I suppose, that, till within a very recent 

 period, no attempt has been made to turn to account the characters pre- 

 sented by the form of the eggs, and these beautiful objects have been 

 altogether neglected. The pajjers upon the ova of certain species of 

 Acidalla and Ennomos, published by Mr. Hellins in this Journal, prove 

 what good characters are afforded, in some cases at least, by the form 

 and size of the eggs. That the differences of form should give some 

 assistance in determining the position or family of certain species, it is 

 my object in this note to suggest ; and as instances, I will select the 

 cases of Asteroscopus nuhectdosa, A. cassinea, Diloha caeruleocephala and 

 JDemas coryli. The majority of, if not all, British authors, have con- 

 sidered that these species should be placed among the true or false 

 BoMBYCES, but Herrich-Schiiffer and some other Eurojjean entomologists 

 have thought their true position is among the Noctu^. What aid then 

 does the form of the eggs of these moths give us in trying to determine 

 the question ? The Notodontid^e, in which family Asteroscopus and 

 Diloha are generally placed, have smooth eggs, with scarcely any 

 sculpture, and not at all resembling the usual Noctua-tj'pe of egg, but 

 those two genera have ribbed eggs (as have the majority of the Noctu^), 

 that of Diloha especially resembling in shape the eggs of some of the 

 Boinhycoidae. With the egg of Demas I am not acquainted, but it 

 probably differs in form from the eggs of the Liparidae, and resembles 

 the Noctua-type. There is nothing, 1 l)elieve, in the structure of the 

 larva? of these three genera which would forbid their being placed 

 among the NocTUiE, while the perfect insects resemble NocTuai far more 



