140 
These are either uni-colorous or of different tints, the veins and 
veinlets being either lighter or darker than the membrane, or 
vice versa, or the former lined on either side more or less by 
lighter or darker borders. 
The chest or pectus is of very uniform structure, and only in 
the genus Hpacra are there any prominent lobe-like expansions 
The ovipositor is more or less straight in the adult, of con- 
siderable length usually, and stout at the base, where the lower 
valves are sharply turned up and quite enclosed by the upper 
ones. The apex is smooth and shining, neither acute nor 
serrated. In the nymph-stage it is shorter than in the adult, and 
often (if not always?) shortly incurved from near the base and 
carried over the back. Its length, curvature, &c., afford good 
characters. 
Size and proportions of the various species appear to be fairly 
constant, also the colouring, which cannot be neglected in 
determination. 
The most prominent characters are, however, found in the 
number, size, and arrangement of the spines of the legs, especially 
of the under side of the hind femora and the upper side of the 
hind tibiz, also the relation they exhibit in number and size 
to each other. The femoral spines are in four to five pairs in the 
majority of the Australian species examined by me, but are 
wanting wholly or partially in rare cases, or increase to nine. 
Those of the hind tibie are quite as variable. Even this charac- 
ter, however, cannot be wholly relied upon, as the numbers not 
only vary within the species, but actual disparity in the same 
individual may occur, obsolete spines being indicated by wider 
intervals or minute tubercles, and increase of numbers by inter- 
calated spinelets separated by narrower interspaces. But the 
greatest uniformity prevails in regard to the movable spines of 
the fore and middle tibie, at least in those examined by me. 
Here the number is five on each margin, the only exception 
observed being a female of Honius tagrinus with four pairs. The 
same remark applies to the spines of the under side of the hind 
tibiz, the usual number being three. The subjoined table of the 
variations of the spines of hind femora and hind tibiz will show 
the extent of the observed variability, rarely obscured by other 
characters, and also serve as a ready means of identification. 
