26b' ORISMOLOGY. 
A. GENERAL ORISMOLOGY. 
I. SUBSTANCE. 
1. Membranous (Membranacea). A fine, thin, trans- 
parent substance. A Membrane. — Ex. Wings of 
Hymcnoptera and Diptera. 
2. Pergameneous (Pergamenea). A thin, tough, and 
less transparent substance, somewhat resembling 
parchment. — Ex. The Tegmina of the Orthoptera*. 
3. Cortaceous (Coriacea). A thicker, flexible sub- 
stance, resembling leather. — Ex. Elytra of Tclc- 
phorus and the Malacodermi. 
4?. Corneous {Cornea). A hard inflexible substance 
resembling horn. — Ex. Elytra of Lncanus Cerrms 
and many other Coleoptera. 
5. Crustaceous (Crustacea). A rigid calcareous sub- 
stance. — Ex. The Shell of a Lobster or Crab. 
6. Callous (Callosa). A substance without pores, 
harder than the surrounding matter, and usually 
elevated above it. — Ex. Elevated parts of the Collar 
in Nofnada. (Mon. Ap. Angl. Apis # b.) b Spots on 
the elytra of Stenocorus (Ti/lostagmus K. MS.) 
bimaculatus and affinities. 
7. Cartilagineous (Cartilaginea). A gristly substance 
between bone and ligament. — Ex. The Tongue of 
many Hymcnoptera. 
8. Subereous (Suberea). A soft elastic substance 
a The elytra of this Order in general differ so materially both 
from membrane and corium, that it was requisite to invent a term 
to distinguish them. 
" Mon, Ap. A)ig/. i. /, v. /', 8. A. c. 
