EXTERNAL ANATOMY OF INSECTS. 415 
the last place to be considered. I shall begin with the 
Mouth, or rather the orifice in which the ¢rophz or or- 
gans of manducation are inserted. In some insects, as 
was before observed, they occupy all the under-side of 
the head, as in the drachnida, Myriapoda, &c.; but in 
the great majority they fill an orifice in its anterior part, 
which in some instances,—as in Lampyris, the Lepido- 
ptera, the Heteropterous Hemiptera, Truxalis, &c.—ap- 
pears to be nearly under the head; but in general it termi- 
nates that part, though it extends further below than above. 
In Chermes, 2 Homopterous genus, the promuscis is 
stated to be in the Antepectus, and consequently the 
mouth ; but, as I shall endeavour to prove to you here- 
after, this is a fallacy. In the males of the species of 
Coccus there is no mouth at all. In that of the elm (C. 
Ulmz) in lieu there are ten little shining points, arranged 
two before and two behind in a line, and three on each 
side in a triangle*. It is to be observed that the orifice 
of which I am speaking is usually much smaller in those 
insects which take their food by suction, the Hemiptera, 
Lepidoptera, Diptera, &c., than in the masticating 
tribes. With regard to the real mouth, or that through 
which the food enters, I have nothing at present to ob- 
serve, except that it lies between the upper-lip and 
tongue, is sometimes covered by a valve, as in Apis, 
Vespa’, &c., and is different in the masticators and 
suckers. 
T shall next offer a few observations seriatim, as they 
stand in the Table, upon the organs of manducation; 
* Reaum. iv. 40. Latreille Fourmis, 328—. 
> Prare VII. Fie. 2. k". 
