122 Annals Entomological Society of America  [Vol. VII, 
9. The anterior nerve trunk divides the longitudinal 
muscles into superficial and deep sets, and the longitudinal 
trachea similarly divides the transverse ones. 
10. The antecosta and ventral precosta arise as speciali- 
zations of the acrosternal insertions of the muscles and exist 
only in specialized segments. The muscles may exist in their 
absence. 
11. Characteristics are pointed out of members of five 
families and characteristic figures are published of a Noctuid, a 
Lasiocampid and a Sphingid. 
12. The following muscles are differently lettered by 
Lyonet in the meso- and metathorax. 
MESOTHORAX METATHORAX | MESOTHORAX METATHORAX 
Gr H only m 3d belly of a 
Ist belly of a G OY 2nd belly of a 
en e only € OY 
d f 6,¢ 65,9 
It is suggested that his lettering of the metathorax be 
adopted in general, but that m be used for the posterior of the 
three muscles he confused as a. 
13. The muscle marked E by Lyonet, and IX by Berlese 
is only a segment in length, both terminations being on the 
antecosta. 
14. Cases occur of wide shifts in the origin and insertion of 
muscles, both relative and absolute, notably in the primitively 
longitudinal ones p, p’, and x, near the midventral line and in 
d and F of Phaeocyma; they should therefore be used with 
a good deal of caution in identifying sclerites or parts of the — 
body, at least where as in the caterpillars the sclerites are 
obsolescent. 
BIBLIOGRAPHY. 
The following items refer to the Lepidopterous larve, Bibliography of the 
other insects may be found in Berlese, 1. c. I, 460. 
LYONET, PIERRE: Traité Anatomique de la Chenille qui Ronge le Bois de Saule. 
La Haye, 1760. 
A complete monograph of caterpillar structure based on Cossus cossus, (family 
Cosside) with numerous engraved plates, illustrating, among other things, 
the entire muscular system and its nerve-supply. 
Luppock, J.: Arrangement of cutaneous muscles of the larve of Pygaera bucephala. 
London, 1858. 
Family Notodontide. 
BERLESE, ANTONIO: Gli Insetti; Milano, 1909. 
A long chapter on insect muscles and their homologies, with figures of Detlephila 
(Sphingide) and numerous non-Lepidopterous insects. 
