276 [May, 



Kermes should not be included in the Coccina, provided that the adult 

 female does not possess the anal plates, and I must admit that my own 

 observations lead me to think that Mr. Maskell's reasons for the es- 

 tablishment of a new group are insufficient. 



The fact of the larvae having what are termed " anal tubercles," 

 such as are seen in the adult of the Coccina, whilst the adults of the 

 same species have anal plates and cleft such as are peculiar to the 

 Lecanina, does not, I think, warrant a separate division. For I find, 

 on examination, that the larvae of the Lecanina, for example, Pulvinaria 

 vitis or Lecanium olece, are furnished with these " anal tubercles," but 

 they seem at an early stage to be superseded by the " anal plates," 

 which I should suppose are the same processes as the former, although, 

 in a more advanced (or retrogressive) stage, in fact, I apprehend that 

 they really form the last dorsal segment. If these " anal tubercles " 

 have not before been observed in the larvae of the true Lecanina, I 

 think it can only be that the insects have not been examined when 

 sufficiently young. In the larvae of Diaspina similar tubercles will be 

 found, but the two long hairs or anal setae are 1 situated not at the 

 termination of the tubercles, as in the Coccina and Lecanina, but ap- 

 parently on the margin between the tubercles. These latter are 

 superposed dorsally, just as in the larvae of Lecanina, and I apprehend 

 form afterwards the median lobes so characteristic of the Diaspina, 

 and which are, I think, always dorsal, the limits of the ventral margin 

 being seen underneath in transparent specimens, as may be noticed in 

 many of Comstock's figures. In the Coccina, at least in the genus 

 Dactylopius and others, these " anal tubercles " do not seem to undergo 

 much modification. Comparative figures of the terminal segments of 

 the larvae of many different genera from the different divisions and 

 sub-families would, I think, show a considerable uniformity of struc- 

 ture, and could not fail to be instructive ; but it appears to me that 

 for the purposes of entomological division of the family we must 

 depend upon the characters of the adult in all cases, and to justify the 

 institution of a fourth group, I cannot help thinking that it would be 

 necessary to find some genera in which the adult female, while pro- 

 vided with the multi-articulate labium of the Coccina, is furnished with 

 the anal plates of the Lecanina. 



I may mention that it is quite possible that I am not correct in 

 my determination of the species figured, which were studied with a 

 view to the structure of the caudal segments as before mentioned, 

 and as Signoret describes such a large number of these two genera 

 {Lecanium and Dactylopius) , it is not difficult to be mistaken, until I 



