The Crayfish: An Introduction to the Study of Zoology

abdominal appendages abdominal somites alimentary Amurland animals antenna antennule aperture appears arthrobranchiæ Astacine Astacus torrentium attached basal joint become blastomeres body branchiæ branchial branchial cavity canal carapace cavity cephalothorax cervical groove chelate chitinous convex corpuscles coxopodite cray Crustacea cuticle cuticular division ecdysis Écrevisses edge endopodite English crayfish epiblast epipodite existence exopodite exoskeleton external eye-stalks fact female filaments fluviatilis.-A food-yelk forceps front ganglia ganglion gastrolith genus gills give rise hind-gut hinder hypoblast inner lamina latter leptodactylus less lobster longitudinal male marine maxillipede modified morphological muscle Nauplius nerve fibres nobilis noble crayfish nucleated cells nuclei organs outer pairs plate pleura podo podobranchiæ portion posterior Potamobiida prawns present protopodite region ridge rostrum septal lines setæ side somite species spermatozoa spines sternal sternum stomach structure substance surface telson tergal tergum terminal thoracic thoracic limbs thoracic somite tissue transverse wall yelk young crayfish zone