228 [August, 1890. 



in Ilia Catalogue considers Aspidiotus saliceti of Bouche to be the same as Chionaspis 

 salicis, auctorum. Lastly, the Mytilaspis abietis, Schrank, is described by Signoret 

 {op. cit., p. 136), who mentions that " Targioni-Tozzetti a fait de cette espece un 

 Lecanium, mais nous pensons, a cause de la citation de Schrank meme qui indique 

 corame synonymie le Chermes arborum linearis, Geoff., p. 509, 17, qu'il ne faut pas 

 le confondre avec Vabietis rotundus, p. 507, 7, veritable Lecanium." I do not see 

 anything in Signoret's description to distinguish this from the typical species of 

 Mytilaspis, and, in accordance with Schrank's own opinion, I think it may be con- 

 sidered a synonym of M. linearis. Mr. Maskeli describes eight species in New 

 Zealand, of which one is 31. pomorum, and the remaining seven are not yet known 

 in Europe or America. Prof. Comstock describes four species in America, of which 

 one is M. pomorum, and the others will be referred to hereafter, and it may be well 

 to recal his observations (2nd Rep., p. 116) on the genus Mytilaspis. He says, " I 

 believe that the recognising of diiJerent species of the Coccidm has been, in many 

 cases, more a matter of feeling than of knowledge, and this has been the case es- 

 pecially in the genus Mytilaspis. There is no doubt that new names have been 

 given to forms simply because they looked a little different from other forms, or 

 because they occurred on a diffei-ent plant." 



I should add that Targioni-Tozzetti, in his Catalogue, 1869, mentions Coccus 

 salicis, and gives it another name, calling it Mytilaspis Maquarti ; but Signoret 

 considered the Coccus salicis of authors as a synonym of Chionaspis salicis. Targ.- 

 Tozzetti likewise catalogues Mytilaspis myrti, Bouche, without furnishing Bouche's 

 designation, which was Aspidiotus myrti (Ent. Zeit., 1851, p. 112), and Signoret 

 Cop. cit., p. 127) considers this as a Chionaspis, but admits that Bouche's description 

 is too short to enable the insect to be recognised with certainty. The Mytilaspis 

 pinifolicB, Fitch, mentioned by Signoret {op. cit., p. 442) has been described by 

 Comstock {op. cit., p. 315) as a Chionaspis. 



Having now glanced at all the various species described by the earlier authors, 

 if I am right in my conclusions, I suppose the synonymy of M. pomorum will be as 

 given above, and I apprehend that the correct designation would be Mytilaspis 

 linearis, Modeer, because, as Mr. Douglas shows (Ent. Mo. Mag., vol. xxiii, p. 28), 

 Modeer was the first to give the species a name in accordance with scientific rules, 

 for Reaumur only called it " Gallinsecte de coquille," and Geoffroy called it " Chermes 

 arborum linearis," whilst Modeer named it Coccus linearis. I have not Modeer's 

 work in my possession, but I quote from Mr. Douglas. 



The characteristic features on the margin of the abdominal segments of this 

 species are — a single marginal secreting glandular opening (called by Prof. Comstock 

 " elongated pore ") between the 1st and 2nd lobes, a double set of similar glands 

 between the 2nd and 3rd lobes, then another similar double set, followed by a similar 

 single gland. Between each such set of single or double marginal secreting glands 

 is a pair of conspicuous plates, and likewise a pair between the 1st and 2nd lobes, in 

 other words, four paii's of plates and four marginal secreting glands (two of which 

 are double), in addition to a pair of plates usually less conspicuous between the 

 median lobes. There is a dorsal spine at the base of each of the median lobes, 

 another at the base of the second lobe, and one adjacent to each second, third and 

 fourth set of marginal glands, making four spines in addition to that on each median 

 lobe. The corresponding ventral spines appear situated between each set of plates. 



