THE ENTOMOLOGIST. 53 



diameter at the base is about the sanoe, but is sometimes 

 narrower than this, and sometimes even broader; from 

 the base to the apex it is thickly and coarsely striped or 

 furrowed, and its surface is smooth. Single galls, or 

 those not very crowded, are perceptible on the outside on 

 short or uneven space of the bark, which latter, however, can 

 only be regarded as a ring, for the base of the gall penetrates 

 farther into the bark than the periphery, so that half of the 

 spacious larva-cell is below the circumference of the cone. 

 The substance of the gall is composed of two thinnish layers : 

 the outer one, of a reddish colour, is doubtless full of sap ; 

 while the inner, which is yellowish, is hard and sharply 

 furrowed, from the circumference of the cone to the apex, in 

 a way that makes the furrows appear deeper at the circum- 

 ference than nearer the apex ; the striae, or the outer layer, 

 unquestionably result from its adhering so closely to the 

 grooves and furrows of the inner layer during the slow process 

 of drying. In old galls the outer layer is generally cracked, 

 and we then only see the brownish yellow inner layer. In 

 this condition the deeper furrows round the periphery of the 

 cone appears as dots ; the aperture through which the imago 

 makes its escape is on the side, and above the periphery of 

 the cone. 



M. von Siebold has been so kind as to send me typical 

 specimens, found at Dantzig and Friebourg on Quercus 

 sessiliflora, and from these it appears that Professor Schenck 

 considers this gall to be that of Cynips corticalis of Hartig. 

 Now, as Hartig's description of Corticalis is such that one 

 cannot distinguish it from A. Sieboldii ; and, moreover, as 

 Hartig doubtless applies the reference to " Malpighi [op. 

 omn. tab. 17, fig. 60"), although the figure of the gall repre- 

 sents that of A. Sieboldii, 1 think it very probable that 

 C. corticalis and C. Sieboldii are synonyms of the same 

 species, and that Hartig, when describing his Corticalis, had 

 only ill-preserved specimens at his disposal. 1 therefore feel 

 justified in retaining the later name, since under that name 

 the gall is minutely described, and typical specimens have 

 been submitted to me for examination. — G. L. Mayr. 

 Synergus incrassatus inhabits this gall. — F. Walker, 

 I think it will be impossible for an entomologist to 

 examine attentively the beautiful figures of the bark-galls, 



