310 Rev. F. D. Morice's Notes on Australian Saw/lies. 



fairly be described -as " sawing."' But there are two objec- 

 tions at least to considering this as the essential distinction 

 between this and the other Sub-orders. In the first place 

 -ill H ymenoptera (the Aculeates, Ichneumons, etc., included) 

 have their ovipositors so far saw-like that their apices are 

 armed with teeth, and are used for making their way 

 through the substances (whether animal or vegetable) on 

 which they are operating very much as a saw makes its 

 way through wood, etc., chiefly by help of its denticulationa. 

 And, secondly, it is only in certain Sawflies that the organ 

 has really a saw-like appearance, with fairly broad blades, 

 and denticulations elsewhere than at the apex. In many 

 cases it is rather lancet -like than saw-like, scarcely to be 

 distinguished from the " sting " of a Wasp or an Ichneu- 

 mon, and in Oryssus, etc., it is practically identical with the 

 terebra of a Cynipid. It may be added, that in all cases, 

 whatever be the general appearance of the organ, all its 

 parts are absolutely homologous — the sliding toothed 

 cutting-blades, their more or less connate " supports.'" the 

 attachments to the apical ventral segments, the complicated 

 arrangements by which the " saws '" are started and guided 

 in their movements, etc., etc. The purpose for which their 

 operations are undertaken (namely, to prepare a suitable 

 " larder " or " refectory," which will provide an unfailing 

 supply of food for the expected offspring) is identical, 

 whether the insect be a Sawfly, or a Cynipid, or even an 

 Ichneumonid, or a Fossor,* for food is food, whether it 

 be animal or vegetable ! On the whole, then, it is the 

 post-basal constriction of the abdomen, rather than any 

 character of the ovipositor, which really distinguishes other 

 Hymenopterous Sub-orders from the Sawflies. 



There are, however, a good many other characters which, 

 at least in the order Hymenoptera, are exhibit* d by Sawflies 

 only; but most of these (e. g. two calcaria instead of one 

 only — on the front tibiae) are not found in all groups of the 

 Sub-order. Always, however, their wings have a greater 

 number of veins. t and this should also indicate " general- 



* It seems to be only in i lie Social Aculeates that the organ is 

 chiefly used for other purposes, as a weapon rather than a tool, to 

 some extent merely fur self-defence, hut more for protection of the 

 community (by repelling enemies, extirpating its useless members, 

 etc., etc.). 



f Except in Oryssidae where the alar venation seems "degraded." 

 And even these have the "lanceolate cell." which is peculiar to 



Sawflies ! 



