CERCERIS. 189 



family, being upwards of one inch in length. Amongst the 

 species from South America, some are remarkable for their 

 departure from the normal type of form, having the first seg- 

 ment of the abdomen prolonged into a long petiole ; the Bra- 

 zilian Philanthi also assume this formation, and have been 

 separated from the rest by Klug, forming his genus Trachypus. 

 Five species have been discovered in this country, and a sixth 

 may probably be added, the Philanthus emarginatus of Panzer ; 

 four specimens are in the collection of British Hymenoptera in 

 the British Museum, but there is a want of certainty as to the 

 locality from whence they came. 



There is no genus of Hymenoptera with which I am ac- 

 quainted, the species of which prey upon such widely different 

 insects for the nourishment of their young : the most abundant 

 and most universally distributed species, C. arenaria, stores up 

 different species of Curculionidse, not confining itself even to 

 those of a particular genus, the selection apparently being deter- 

 mined by the abundance of any species suitable for its purpose ; 

 thus, although Strophosomus faber is usually its prey, I have 

 observed it conveying Balaninus Nucum ; on another occasion 

 I captured several with Otiorhynchus sulcatus. St. Fargeau 

 imagined that the beetles were deposited by the Cerceris when 

 soft and recently disclosed, but such is certainly not the case ; 

 the specimens of 0. sulcatus were so hard, that it was with diffi- 

 culty they could be pierced with a pin : the larva of Cerceris is 

 not developed until the beetles have been buried some days, by 

 which time the dampness of the ground renders them sufficiently 

 soft for the larva to feed upon. 



Cerceris interrupta I have observed provisioning its cells with 

 Apion rufirostre ; this species selects hard trodden pathways for 

 its burrows. 



Cerceris ornata is the most subject to variation in its colouring 

 of any species of the genus ; it provisions its nest with different 

 species of Halicti. I have captured it with H. rubicundus, H. 

 zonulus, and H. cylindricus (females). This species is extremely 

 partial to the flowers of the wild Bryony, to which it is sure to 

 be attracted if that plant grows in the neighbourhood of its 

 colony. 



Cerceris labiata I have taken abundantly on several occasions ; 

 I captured it conveying specimens of Haltica tabida ; it is fond 

 of reposing on the flowers of the Herb-Yarrow (Achillea Mille- 

 folium). 



