APHIDIVOROUS OEABEONIDTE. J ()] 



description of the group was furnished to the Entomo- 

 logical Society of France, in 1866, by Dr. J. Giraud. 

 To this Memoir,* which is confined to a description of 

 those Hymenoptera which excavate the pith within the 

 dry twigs of the bramble, I am indebted for many of 

 the details following. 



I may be permitted in a general way to extract 

 certain portions, which set forth the curious instinct 

 shown by these insects in the manner of constructing 

 their cells and storing them with suitable food. 



Giraud says " that, previous to his own observations, 

 but twenty-seven species of insects were known to 

 excavate the stems of the briar for the purpose of 

 constructing their nurseries, but in 1866 he had been 

 able nearly to double this list." 



Dr. Giraud continues, " Their parasites, which are 

 numerous and of various genera, sometimes attack one 

 definite species ; in other cases they are less exclusive 

 in their choice of victims, and concern themselves 

 with species of different genera." " Pourvu que les 

 larves dont leur progeniture doit se nourrir puissent 

 fournir une alimentation suflfisante. Cette prevoyance 

 de la mere n'est jamais en defaut. Quelque fois elle 

 separe les sexes et confie les males, qui sont generale- 

 ment plus petits a des especes dont la taille est en 

 rapport avec la leur ; tandis que les f emelles devorent 

 des especes differents et de plus forte taille," &c. &c. 



These words are somewhat ambiguous, and might be 

 taken to refer either to the larvte of the constructor of 

 the nests, or the larvae laid up as provisions for her 

 own young, but Sir Sidney S. Saunders kindly allows 

 me to quote some of his remarks, which seem much 

 to clear the sense of the above passage, and illustrate 

 the remarkable economy of these creatures. 



Translating the above, he says, " Sometimes she 

 separates the sexes (of her brood ?) and confides the 

 males, which are generally smaller, to victims of corre- 



* J. Giraud, " Insectes qui liabitent les tiges seches de la Ronce," 

 ' Ann. de la Soc. Ent. de France,' torn, xvi, pp. 443 — 500, 



VOL. II. 11 



