84 INSECTA. 
This family is composed of two tribes. 
In the first, that of the Tenrnrepinet#, Lat., vulgarly 
termed Mouches-a-scie, or Saw-flies, we observe elongated 
and compressed mandibles ; a trifid or sort of digitated ligula 5 
an ovipositor formed of two serrated, pointed blades, united 
and lodged in a groove under the anus. The maxillary 
palpi are all composed of six joints, and the labials of four 
the latter are always the shortest. The wings are always di- 
vided into numerous cells. ‘This tribe forms the genus _ 
TENTHREDO, Lin. 
The cylindrical abdomen of these Insects which is rounded poste- 
riorly, composed of nine annuli, and so closely joined to the thorax 
that the two seem to be continuous; the ragged appearance of their 
wings; the two little rounded, granular, and usually coloured bodies 
situated behind the scutellum, together with their heavy port, cause 
them to be easily recognized. The form and composition of the an- 
tenne vary. Their mandibles are strong and dentated. The ex- 
tremity of their maxillz is almost membranous, or less coriaceous 
than their stem. Their palpi are filiform or nearly setaceous, and 
consist of six joints. The ligula is straight, rounded, and divided 
into three doubled portions, the intermediate of which is the nar- 
rowest; its sheath is usually short, and its palpi, shorter than the 
maxillaries, consist of four joints, the last almost bordering on an 
oval. The abdomen of the female presents at its inferior extremity 
-a,double, movable, squamous ovyipositor that is serrated, pointed, 
A, lodged between two concave laminz, forming its sheath or 
case. 
It is by the alternate action of the teeth of this ovipositor, that the 
Insect makes a number of little holes in the branches, and various 
other parts of trees and plants, in each of which it first deposits an 
egg, and then a foaming liquid; the use of which, it is presumed, is 
to prevent the aperture from closing. The wounds made i in this 
way become more and more convex by the increasing size of the 
egg. Sometimes these excrescences assume the form of a gall-nut, 
either ligneous or soft and pulpy, or resemble a little fruit, accord- 
ing to the nature of the parts of the plant that are affected by them. 
These tumours then form the domicil of the larvze which inhabit 
them either solitarily or in society. There they undergo their met- 
amorphosis, and issue from them through a circular opening made 
in their parietes by the teeth of the Insect. Generally speaking, 
