1865.] 333 



[ will close this introductory paragraph by briefly stating the points 

 which deserve an early investigation from those who are so situated as 

 to be able to devote themselves to it. 



1. The species Cynips pezomachoides, forticomis and Mrta, known 



in their wingless form only, have been referred by me to Teras Hartig, 

 because they do not possess the principal character ascribed by this 

 author to Biorhiza, an almost obsolete scutellum (" scutellum subnul- 

 lum" Hartig). Their scutellum is as large, and even larger, than that 

 of the wingless specimens of the European Andrlcus (Teras) terminal-is 

 which I have received from Dr. Reiuhard. It is singular enough, 

 however, that the winged form of these species has not been discovered 

 yet, and it would be worth while to breed the galls in larger numbers 

 in order to obtain this winged form, if it exists. 



2. The dimorphism of certain female Cynipidse being accepted as an 

 apparently well established fact, it remains now to be investigated how 

 far this mode of reproduction is general in this family. The only 

 dimorphous female as yet discovered belongs to a particular group of 

 Cynipidse, occurring on the black and red oaks only, and having certain 

 characters in common, which probably will cause this group to be sepa- 

 rated as a distinct genus. (The details of these characters will be given 

 at the proper place below.) This group, as far as I can understand. 

 is foreign to Europe. 



The following questions arise at once: — 1st. Is this character of 

 dimorphism common to the whole group above alluded to ? This 

 can be easily ascertained, I think, by subjecting galls of C. singula- 

 ris, for instance, or any other common species of the group, to the 

 same process of observation as Mr Walsh applied to the galls of 

 C. spongijica. 2d. Are the other species of the black, red and wil- 

 low-oak group, species known as yet in the female sex only, dimor- 

 phous forms of some as yet unknown bisexual species ? This applies 

 especially to G. punctata (podagrse) of which more than one hundred 

 females have been reared without any male, and to C formosa, which 

 shows rather striking structural affinities to the agamous female of ('. 

 spongijica {(J. acindata olim.) 3d. Are the 39 European species be- 

 longing to the agamous genus ([//nips Hartig, the four or five North 

 American species belonging to the same genus, and the European aga- 

 mous species of Neuroterus, all dimorphous females of some known or 

 unknown bisexual species? This is the most important question of all. 

 and the most difficult to solve by means of an a priori reasoning. If. 

 on one side, we cannot but concur in the views expressed by Mr. Walsh 



