200 [Febiuaiy, 



I at first thought that the specieg must be uew, as the female 

 insect does not entirely agree with any described species that I am 

 aware of ; but I am now induced to think that my specimens are 

 Aspidiotus zonatus, Frauenf.j = quercus, Sign., and that the females 

 which have been described by Signoret {I. c.) and by Mr. Douglas 

 (Eut. Mo. Mag., xxiii, pp. 150, 151) must have been young individuals, 

 whilst those which I have found are the fully developed adults, and 

 it will be necessary to give my reasons for coming to the above 

 conclusion. 



Signoret describes two species of Aspidiotus as feeding on the oak. His A. 

 ilicis (Ess. Cochen., p. 97) cannot, I think, be identified with that which I have 

 found, either from description or figure {op. cit., pi. iv, figs. 3, 3«). 



His description of A. quercus {I. c.) agrees in some respects with my examples ; 

 for instance, speaking of the scales, he says, " Celui des femelles est arrondi, celui 

 des males tres allonge, avec la depouille au centre et jaune." This description en- 

 tirely agrees with my specimens ; but, on the other hand, he states that he has not 

 been able to see any groups of spinnerets in the female, whereas my specimens show 

 four groups. 



In describing the male, Signoret writes (l. c), "Les antennes sont courtes." I 

 did not find any perfect male iinago on my oak leaves — only pupte, but Mr. Douglas 

 kindly sent me some leaves of the same species of oak as my own, and on those I 

 found more than one male. These had elongate antennae, about the length of the 

 body of the insect. 



Mr Douglas gives the measurement of his male scales as ranging from 1"075 

 mm. to 1'45 mm., and those of his which I measured I found to be about I'llS mm., 

 whilst my own measured about 1'25 mm. I do not see any difference between those 

 which he sent me and my own, as regards colour or shape, and after making allow- 

 ance for the important discovery by Mr. Douglas {I. c.) of the discrepancy as to 

 measurement in Signoret's translation of Frauenfeld's description of A. zonatus, I do 

 not think there is any reliable difference between the male insect and scale of the 

 A. zonatus, Frauenf., and those found by Mr. Douglas and myself. 



Signoret (op. cit., p. 106), referring to his A. quercus, states that it appears to 

 him distinct from A. zonatus, but he afterwards appears to have modified his opinion 

 on this point, and refers to the two species as being synonymous (op. cit., pp. 511, 

 630), and he finally afBrms this to be the case in his letter to Mr. Douglas (Eut. Mo. 

 Mag., xxiii, p. 151). 



Therefore, as far as the male is concerned, there seems sufficient reason for con- 

 cluding that my specimens are of the same species as those found by Dr. Signoret in 

 France, Mr. Douglas in England, and by Frauenfeld in Austria, viz., A. zonatus. 



As regards the females, however, an important distinction between A. quercus, 

 Sign., and my specimens consists in the absence of spinnerets in the former, and the 

 presence of four groups in the latter, and on examining those received from Mr. 

 Douglas, of which there were very few females, I find the same difference ; but with 

 this exception, viz., absence of spinnerets, Mr. Douglas' specimens show the same 

 cliaracters as my own. I should suppose that those which Mr. Douglas sent me are 



