XXXIX 



The same diligent observer has more recently ascertained that 

 the subterranean brood of the Phylloxera of the vine is also con- 

 tinued from 3^ear to year by a similar sexual race, which appears 

 later than that derived from the winged type (about the middle 

 of October), but perfectly identical therewith, the females of 

 both producing only a single egg {Voeuf d'hiver of Balbiani) ; 

 whereby, in the one case, the continuity of the race is main- 

 tained for several years upon the same root until this is entirely 

 exhausted ; while, in the other, by the intervention of the winged 

 type, new colonies are dispersed far and wide. 



M. Balbiani also states that certain abnormal forms, occa- 

 sionally found mingled with the winged type, noticed by him 

 in several other species and formerly considered as males, are 

 rather to be regarded as females with atrophied characters, some- 

 what analogous to the neuters of social Hymenoptera.* 



Some strange theories, however, have been propounded by 

 M. Lichtenstein, as to certain phases in the genetic cycle of the 

 race, whereby it is alleged that the winged Phylloxera of the 

 vines resorts to the Kermes oaks {Quercus coccifera) to deposit- 

 not eggs hilt— pupa, from which such sexual race is developed as 

 aforesaid ; this winged type being characterized as " Androphores " 

 and " Gynephores," according to the sex of the pupcs deposited 

 by these so-called " flying cocoons." 



' M. Balbiani, however (on examining other specimens taken by 

 himself), maintains that the author of this startling hypothesis 

 has confounded two distinct species ; that alluded to as aforesaid 

 being, as he conceives, a new species (to which he gives the name 

 of P. Lichtensteinii),f differing from P. vastatrix in all stages of 

 development, including that of the sexual race ; while the manner 

 in which it had been sought to explain the return of the progeny 

 of the latter from the oaks to the vines, by means of a second 

 supposititious winged-type, would be contrary to all the analogies 



of the genus. 



M. Lichtenstein demurs to these conclusions and repudiates 



the name given by M. Balbiani, alleging :— _ 



1. That the species adverted to by the latter is not new being 

 his P. Rileyi, described also by Kaltenbach (in 1873) under the 

 name of P. corticalis : 



* Compt. Kend., 21 Sept., 187i; p. 687. 

 + Ibid., U Sept., 1874; p. C45. 



