108 HVMENOPTERA 



CHAP. 



The habits of one species of this genus have been fully de- 

 scribed by Fabre ; he assigns to the species the name of S. flavi- 

 pennis, but Kohl considers that it is more probably S. maxillosus. 

 This Insect forms its nests, in the South of France, in the ground, 

 excavating a main shaft with which are connected cells intended 

 for the reception of the provisions for the young. The entrance 

 to the burrow is formed by piercing a hole in the side of a very 

 slight elevation of the soil. Thus the entrance to the construc- 

 tion consists of a horizontal gallery, playing the part of a vesti- 

 bule, and this is used by the Sphex as a place of retreat and 

 shelter for itself; at the end of the vestibule, which may be two 

 or three inches long, the excavation takes an abrupt turn down- 

 wards, extending in this manner another two or three inches, 

 and terminating in an oval cell the larger diameter of which is 

 situate in a horizontal plane. When this first cell has been com- 

 pleted, stored with food, and an egg laid in it, the entrance to 

 it is blocked up, and another similar cell is formed on one side ; 

 a third and sometimes a fourth are afterwards made and pro- 

 visioned, then the Insect commences anew, and a fresh tunnel is 

 formed ; ten such constructions being the number usually prepared 

 by each wasp. The Insect works with extreme energy, and as 

 the period of its constructive activity endures only about a month, 

 it can give but two or three days to the construction and pro- 

 visioning of each of its ten subterranean works. The provisions, 

 according to Fabre, consist of a large species of field-cricket, of 

 which three or four individuals are placed in each cell. Kohl 

 states, however, that in Eastern Europe an Insect that he 

 considers to be the same species as Fabre's fyhex, makes use of 

 locusts as provisions, and he thinks that the habit may vary 

 according to the locality or to the species of Orthoptera that 

 may be available in the neighbourhood. However that may 

 be, it is clear from Fabre's account that this part of the 

 Sphex's duties do not give rise to much difficulty. The cricket, 

 having been caught, is paralysed so that it may not by its 

 movements destroy the young larva for whose benefit it is 

 destined. The Si^liex then carries it to the burrow to store it in 

 one of the cells ; before entering the cell the Insect is in the 

 habit of depositing its prey on the ground, then of turning round, 

 entering the burrow backwards, seizing as it does so the cricket 

 by the antennae, and so dragging it into the cell, itself going back- 



