'with an Account of its Dcvelopement. 491 



known, but which will be fully described in my forthcoming 

 Essay upon the Bees of Great Britain. Upon a subsequent 

 visit to the same spot in the beginning of September, he was 

 anxious to capture more specimens of the bee, finding it a 

 choice acquisition to his own collection, and a desideratum to 

 his friends ; but, as it was to be expected, he was too late to take 

 it; when, fortunately, it occurred to him to secure several of these 

 bramble sticks, having first ascertained, by opening some of 

 them, that there was a certainty of succeeding in his object 

 by finding the tube occupied by the infant grub. It is a 

 remarkable fact, that not in one single instance did the insect 

 which he bred from these sticks prove to be the much wished 

 for bee ; but, instead of it, a more desirable acquisition, 

 namely, an entirely new species of wasp, of the subgenus 

 O'plopus of Wesmael*, the Epipone Kirby of the British 

 catalogues, and congeneric with the Vespa spinipes Linn. 

 It does not appear that he had ever captured the new insect 

 at the place, although a most assiduous collector ; and the 

 answer to the question of how they supplanted the O'smia, if 

 ever the O'smia occupied the same sticks, is one to which 

 much interest attaches. Is this wasp a parasite ? Reasoning 

 from analogy, I should say not ; for its congener, the Vespa 

 spinipes, supplies its larva with small caterpillars. But in 

 this instance may I safely reason from analogy, as its habits 

 of construction are dissimilar to the well-known habits of the 

 O. spinipes, which forms a trumpet- shaped projection of the 

 agglutinated particles of fine sand upon the vertical face of a 

 sand-bank ? Modifications of instinct are of daily observation ; 

 and may not the present be an instance of it, and the insect, 

 to save labour, having found^these excavated sticks suited to 

 its purposes, adopted them for the burrows of its young ? I 

 hesitate, however, in taking this view, and consider that we 

 have before us the constant and uniform habits of the crea- 

 ture; and I am strengthened in my opinion by the circum- 

 stance of the cylindrical cavity of these sticks, occupied by 

 the young of this wasp, being invariably used with a coating 

 of agglutinated particles of sand. Consequently, if it resorted 

 to the sticks, to save the labour of excavating and building, it 

 would dispense with this unnecessary task; and this fact also 

 confirms me in my opinion, that the insect is not a parasite 

 upon the bee, and that these sticks were never occupied by 

 the O'smia. Although not a parasite itself, this wasp appears 

 to be infested by one, namely, a new Cryptus Grav., bred 



* Bulletin de l'Academie Royale des Sciences et Belles Lettres de 

 Bruxelles, 1836, No. 2. p. 45, 



