INTERNAL ANATOMY OF INSECTS. 173 
to the sole of the foot, and by several heads to the skin 
of the animal; so that they can draw the proleg within 
the body or push it out, and perform other necessary 
movements ?. 
I shall now call your attention to the muscles of the 
perfect insect, as they move the head and its organs; the 
Trunk; the Abdomen; and the Viscera. 
i. The Head. ‘This part in insects moves upwards, 
downwards, inwards, to right and left, is pushed forth 
or drawn in, is often capable in part of a rotatory move- 
ment, and is sometimes versatile, turning as it were upon 
a pivot. All these movements are of course produced 
by an appropriate apparatus of muscles, which have their 
attachment in the anterior part of the trunk, mostly in 
the manitrunk, while their insertion is in the posterior 
part of the head, in the margin of the occipital cavity. 
To enumerate and describe them all would be tedious 
and uninteresting—I shall only mention some of the 
principal ones. ‘The levators of the head are usually a 
pair of muscles situated in the manitrunk, to the upper 
side of which they are attached, and perhaps in Colco- 
ptera and some others to the phragma, which probably 
Cuvier means by the anterior part of the scutellum® ; 
they are inserted in the posterior margin of the upper 
part of the head, in Coleoptera in a pair of notches (My- 
oglyphides‘), or a single one’. In Calandra Palmarum 
these muscles as they approach the head, to judge from 
the dead animal, divide into ¢wo branches or a fork: 
thus, as the muscle-notches are wide in this insect, the 
4 Vou. IIl. p. 135—. > Anat. Comp. i. 447. 
¢ Vou. II. p. 367. Prats XXVII. Fic. 1, 4.0’. 
4 [bid. Fic. 3. n’. 
