18M.J '43 



Dinspis ostreaeformis not only with A. circularis, but also with A. 

 furfurus. It ia only in his " Table generale des especea " (op. cit., 

 502j that he mentions A. circularis as equivalent to Diaspis ostrecs- 

 formis, but in his description (p. 123) and catalogue (p. 60) he regards 

 A. furfurus, Fitch, as a synonym of D. ostreceformis. A. furfurus 

 has, however, been proved from examination by Comstock to be a 

 different species (1st Ag. Eep., 1880, p. 315), Signoret states that 

 Diaspis Harrisii, described by Walsh in " Pract. Ent." (1866), vol. ii, 

 p. 31), is also a synonym of D. ostrecefoi'mis, and is very precise on 

 this point, saying (J. c.) " I'ayant re9ue dans ces derniers temps nous 

 avons pu nous en assurer." Comstock says that " this statement is 

 evidently a mistake." I have not seen Walsh's account of his species 

 which he appears to have first named Coccus Harrisii, but T presume 

 from the name that he considered it identical with the species described 

 by Harris, but not named (Harr., Treat, on Ins., 1852, p. 220), and it 

 appears to me that pei'haps here has occurred the mistake. It must 

 be remembered that Harris mentions two species, one which he con- 

 sidered as the Coccus cryptogamus, Dalman, and which Comstock 

 considers approaches Chionaspis furfurus, Fitch, Comst., and another 

 which he says resembles " in shape " one which was described by 

 . Eeaumur in 1738. Now Reaumur's insect we know is a Mytilaspis, 

 and the shape is, of course, perfectly different to the Diaspis ostrecd- 

 forinis. Therefore, as Signoret so definitely states that his D. 

 ostreceformis is the same as Walsh's species which he received, I think, 

 perhaps, we should accept that statement ; in which case it follows 

 that Walsh's species is not the same as that of Harris, and, conse- 

 quently, Coccus Harrisii, Walsh, Aspidiotus Harrisii, Walsh, and 

 Diaspis Harrisii become synonyms of D. ostreceformis. Signoret 

 named the species D. ostreceformis believing it to be identical with the 

 A. ostreceformis described by Curtis in 1843, but as this has already 

 been shown by Mr. Douglas to be an error, the name Diaspis Harrisii 

 would have priority. On the other hand, it seems probable that A. 

 circularis. Fitch, is identical, although it cannot be stated with cer- 

 tainty, as Prof. Comstock, who has seen Fitch's collection, says 

 (Comst., 2nd Eep. Corn. Un. Exp. Stn., p. 94), that "from the frag- 

 ment of scale in the private collection of Fitch it would be impossible 

 to recognise the species." But I see nothing in Fitch's description of 

 his species as quoted by Signoret {op. cit., p. 439) to prevent it from 

 being the D. osfreaformis, although the description is very imperfect, 

 and might apply to many Aspidioti. On the whole, although the 

 specific name circularis has priority, if the species is the same, and if 



