Operc"lum of Scorpion, [189], [206], [212], [372]

Operc"lum of Thelyphonus, [189], [190], [206]

Organs, arrangement of, [10]

Org"ns, auditory, of arachnids and Insects, [368]

Org"ns, branchial, innervation of vertebrate, [151]

Org"ns, bran"hial, sense-organs of embryo vertebrate, [261], [281]

Org"ns, chordotonal, of insects, [364], [369], [370]

Org"ns, electric, [470]

Org"ns, generative, of Limulus, [208], [209]

Org"ns, gener"tive, connection between Thyroid gland and, [215]