HYMENOPTERA. TEREBRANTIA. 157 



in many instances nearly parallel, except towards the 

 end, which is always pointed. 



The antennas vary considerably, not only in the genera, 

 but even in the sexes. They are sometimes club-shaped 

 (Cimbex), sometimes long and thread-like (Tenthredo) 

 with many joints of nearly equal length ; whilst sometimes 

 (Hylotoma), they consist of but three joints, two very 

 short, and the third forming nearly the whole of the 

 antennae. The number of joints varies from 3 to 30. The 

 antennaB of the males are sometimes exceedingly beautiful 

 in form. In one species it is feathered and resembles that 

 of the Silkworm-moth. In another, the last joint (which 

 forms nearly the whole length of the antennae) is forked 

 from its base, giving the insect the appearance of a pair 

 of double straight horns. The wings are large, and when 

 in repose lie horizontally on the back, overlapping each 



Fig. 49. 



Leg of Sawfly (Trichiosoma). 



other ; the legs are of moderate length, or rather long, 

 and have a series of curious sucker-like appendages 

 attached to the tarsus. In some, if not all the species, 

 the claws are cleft or forked. 



In colour and markings the species vary much. 

 Tenthredo viridis, scalaris, and punctatus are of a beau- 



