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that year, the author records the fact of having himself hrccl both sexes of 

 Cynips spougifica from the galls of the black oak of North America. These 

 galls resemble those of Cynips KoUari, being globular, rather larger than 

 the European galls, but of the same hard woody consistency externally, 

 and of the same spongy substance inside. Mr. Walsh adds, ' By the fore- 

 part or middle of June both male and female gall-flies eat their way out 

 of a certain number, say about one-fourth part; the remainder are not 

 developed until about two months later.' In a private communication 

 from Mr. Walsh, I learnt that he had, like myself, bred hundreds of the 

 gall-flies from galls collected late in the autumn, all these proving to be 

 females, and that it was not until he made collections of galls in summer, 

 when a partial development of flies takes place, that he obtained the male, 

 this sex being as" one to many hundreds of females. At length he bred 

 three males, one of which he kindly forwarded to me, and which 1 exhibited 

 at a meeting of this Society. Following up Mr. Walsh's method of collecting 

 the galls of Cynips Kollari early in the season, — that is, just at the time 

 when they are becoming hardened, and before any flies have escaped from 

 the fresh galls, — I have tried, but hitherto without success, to obtain males 

 of Cynips; but I advise all who are interested in the matter to pursue the 

 same plan, always remembering that these mysteries of nature are only 

 unfolded at intervals, and then only to favoured votaries. 



" With respect to the obtaining of males of Nematus gallicola, I believe 

 that any one may collect, even early in the season, thousands of the galls of 

 that insect without obtaining a male ; but in all probability, by persevering 

 season after season, his efforts will, as in my own case, be crowned with 

 success ; but I feel assured that unless the galls are gathered before any 

 of the flies have escaped, he will have little or probably no chance of 

 success. The same care must also be taken in collecting the galls of 

 Cynips KoUavi; collecting them early, just at the time when they harden 

 and become woody, for it is out of the flies first developed that the male 

 may be expected to be found. My having bred thousands upon thousands 

 of flies without obtaining a male should prove a stimulus to others, for that 

 a male exists I think Mr. Walsh has determined beyond question. The 

 impregnation of a single female may possibly be sufficient to render her 

 progeny, and their descendants, for several generations, equally fertile ; and 

 the same may possibly be the history of Nematus gallicola. The male bred 

 by Mr. Walsh is said not to belong to the restricted genus Cynips, but to 

 one not represented in Europe. This may be the case ; but in all essential 

 generic characters it agrees in a remarkable manner: 'spougifica,' like 

 Cynips proper, has thirteen -join ted antennae ; the neuration of the wings is 

 the same, and uo difference is perceptible in the construction of the legs ; 

 the difTerences that are perceptible are in its abdomen being less com- 

 pressed, and it is glabrous ; there may be some other minor differences ; 



