BIOLOGIA CENTRALI-AMERICANA. 



ZOOLOGIA. 



Class INSECTA. 



Order HYMENOPTERA. 



ACULEATA. 



Under the designation of 'Aculeata' are included the Hymenoptera commonly 

 called Wasps, Ants, and Bees, the other section of the Order with petiolated abdomen 

 being called ' Terebrantia.' As a matter of fact I do not see how any clear line of 

 demarcation can be drawn between the ' Aculeata ' and the l Terebrantia,' nor am I 

 sure that they can be separated by any one structural character. It is doubtful if 

 Hartig's divisions of ' Ditrocha ' and * Monotrocha ' can be looked upon as altogether 

 satisfactory; for, like most classifications based upon a single character, it would 

 separate groups which agree in many points to place them near those with which they 

 agree in one only. 



The Aculeata include four more or less clearly denned sections — the ' Fossores,' 

 ' Diplopteryga,' ' Heterogyna,' and the ' Anthophila.' 



Section FOSSORES. 



This section contains the sand- and wood-wasps and the Mutillidee. From the 

 ' Heterogyna ' (Ants) they are recognizable by the abdominal petiole having neither 

 scales nor nodes, in which respect they agree with the ' Diplopteryga '; the ' Fossores,' 

 in fact, only differ from the latter in the wings not being folded longitudinally in repose. 



Pam. SPHEGIMI. 



This family is tolerably well defined by the neck-like prothorax, the hinder angles 

 of which do not reach to the tegulse, and by the smooth, cylindrical petiole. 

 biol. CENTE.-AMEE., Hymenopt., Vol. II., October 1888. bb 



