§ 3. 
For the determination of genera, Jurine’s work will 
be found the most useful of all the preceding books, that is 
to say, as far as it refers to the Fossorial Aculeates. He 
merits great praise for the application of a system—the 
utility of which had not been fully recognised by its dis- 
coverer either Harris or Frisch—to a tribe of insects which 
still remained, notwithstanding the labours of Fabricius, 
Latreille and Oliver, in detail a confused mass very difficult 
to ascertain with perfect accuracy or satisfaction. The 
characters derived from the organs of the mouth, made use 
of by the former writer, are, perhaps, as good and as per- 
fectly distinct as any that could be adopted, were they not 
in the majority of cases too recondite for easy investiga- 
tion, exclusive of the excessive labour of inspecting them 
fully. But we shall even then find the number of their 
parts frequently the same, differing only in form, and that 
so slightly that recourse must still be had to external 
characters to substantiate and confirm them. But when 
characters are pointed out to us in a group of insects already 
combined by one still more important, which are so simple, 
that the first glimpse will inform us, even when we have not 
the clue of habit* to guide us, whether an insect be of the 
same or of a different genus with those with which it is 
compared, should we not be grateful to the individual who 
discovered or applied it; and this is due to Jurine. He saw 
in the neuration of the superior wings of the majority 
of the Hymenoptera differences, which he found would 
separate them generically from the circumstance of its 
assembling together such which perfectly agreed in all 
* This word, in the singular, [ always apply to the general appearance, the 
facies of the insect. 
B2 
