398 Professor E. B. Poulton on 



conclusions which at present seem to be justified may be 

 confirmed or modified.* 



The instincts of certain moths with phytophagous larvae 

 do not seem to be equally perfect. I have often observed, 

 and every student of Lepidoptera must have noticed, that 

 the large solitary larva? of SphingidcV are far more 

 frequently found upon small bushes of their food-plant 

 than upon large ones. It appeared to me that the 

 explanation was tx) be found in the instincts of the parent 

 moth leading her to deposit two or three eggs on each 

 bush or tree, irrespective of size. If this were the case, 

 the larvae would of course be much easier to find and 

 their effect upon the food-plant far more conspicuous upon 

 the smallest bushes. However this may be, the parental 

 instinct is certainly liable to error, for such large larvae 

 may occasionally be found still immature upon a bush so 

 small that it has been completely denuded of its leaves. 



II. NEUROPTERA. 



Records of the attacks of predaceous insects are very 

 scanty in all Orders except the Diptera and Fossorial 

 Hymenoptera. It is hoped, however, that the following 

 brief tabular statements will draw attention to the great 

 need for a large body of accurate observations. 



Leaving the Hymenoptera to form Part II of this Memoir, 

 because of the voluminous literature and the fact that 

 Fossors are predaceous in a somewhat peculiar and special 

 sense, the remaining Orders are arranged in a succession 

 determined by the number of records. The Neuroptera 

 follow the Diptera, because the list of examples, although 

 sliort, is longer than that of any except the tvvo chief 

 Orders. 



* Compare Professor A. Giard's observation that the larvae of 

 Melanostorna mellinmn, L., generally supposed to feed upon Aphides, 

 can be reared njion Musca domestica and Chotinphila pusilla (Bull. 

 Soc. Ent. Fr. 1896, p. 234). Quoted in Verrall's British Flies, p. 

 303 (bottom line) and p. 311 (lines 12-17). 



