#Ceph' al o-tho' rax#, the division of the body formed by the fused head and thorax in many arthropoda. #Cer' vi cal groove#, the groove marking the place of union when head and thorax are merged into a cephalo-thorax. #Cha la' za#, one of the spiral masses of albumen found at the two ends of a bird's egg. #Che' li peds#, the large claws in many crustaceans. #Chor-date#, animals with a notochord, present throughout life or disappearing. #Chro mat' o phore#, color body. #Chrys' a lis#, the pupa stage of a butterfly. #Cil' i um# (pl. #cilia#), a minute vibrating hair on the surface of many cells. #Co coon' #, the envelope spun by certain larval insects in which they are inclosed during the pupa stage. A similar structure, as the egg-case of spiders, earthworms, etc. #Cœ' cum# (se' kum), a blind pouch or bag; a sac open at one end. #Cœ len te ra' ta#, rather simple, sac-like animals with nettle cells in the body walls. #Co le op' te ra#, beetles. #Col' o ny#, a group of animals of the same kind found in one locality, usually related to each other and often actually connected. #Com men' sal ism#, an association of two animals, not mutually helpful, but without injury to either. #Com pound eye#, an eye made up of many simple eyes or eye elements. #Com pressed' #, narrower from side to side than from dorsal to ventral surface. #Con ju ga' tion#, a process occurring in some one-celled animals, preceding reproduction. In this process two animals unite temporarily and exchange nuclear substance, or in some forms the two cells fuse into one. After this exchange or fusion fission occurs, usually more rapidly than before. #Contracting# or #pulsating vacuoles#, small, clear spots in a cell, filled with a watery fluid. In the living animal these alternately disappear and then reappear. #Co' nus ar te ri o' sus#, a cone-shaped artery connected with the ventricle of the heart. #Cov' ert#, a feather overlying the base of the large feathers of the wing or tail. #Cra' ni um#, the skull, particularly that part of it inclosing the brain. #Crop#, an enlarged portion of the esophagus. #Cross fertilization#, a form of fertilization in which the male and female elements are produced by different individuals. #Crus ta' ce a#, aquatic, gill-bearing arthropods, with two pairs of antennæ. #Cu' ti cle#, the thin outer skin. #Cy' to plasm#, the portion of the protoplasm of a cell which is outside of the nucleus, less dense than the nucleus and usually taking a lighter stain. #Den' ta ry#, the terminal portion or bone of the lower jaw of vertebrates lower than mammals, containing all or most of the teeth. #Di a phragm#, a muscular partition separating the abdomen and thorax, in mammals. #Dig' i ti grade#, walking on the toes. #Di œ' cious#, reproductive organs in different individuals. #Dip' te ra#, insects with two wings, including flies, mosquitoes, etc. #Dis' tal end#, the free end of any object which is attached by one end.