392 BIOLOGY 



carotids. The two large arteries on the sides of the neck carrying blood 



to the head, 190. 

 carpals, 182. 

 carpels (Gr. carpos = fruit). The separate parts (leaves) of which a pistil 



is composed, 120. 

 cartilage. A hard material, softer than bone, which forms part of the 



skeleton, 27, 35. 



cartilage bones. Bones first formed as cartilage, 181. 

 casein. A proteid present in milk and constituting the curd, 8. 

 castor bean, 103. 

 cat, 366. 



caudal. Pertaining to the tail, 

 cell. One of the simple units of which living things are composed, 20, 



37. 



cell doctrine, 38. 



cell sap. A clear liquid inside of plant cells, 30. 

 cellulose. A material related to starch and forming the cell wall of many 



plant cells; the basis of paper, cotton, etc., 35. 

 cell wall. The covering on the outside of the cell, not present in all cells. 



29, 34. 



central nervous system, 162, 192. 

 centrosome (Gr. centron = center + soma = body). A small body lying 



near the nucleus in animal cells and apparently the center of active 



forces, 29, 34. 

 centrosphere, 34. 



centrum. The large central disk of bone in a vertebra, 177. 

 cephalic (Gr. kephale = head). Pertaining to the head, 

 cerebellum. The larger of the two divisions of the hind-brain, 193. 

 cerebral ganglia. The large ganglia in the head of an animal, usually two 



in number, 162. 



cerebral hemispheres. The anterior and largest part of the brain of ver- 

 tebrates, 193. 

 cerebrospinal axis. The central nervous system of vertebrates, composed 



of brain and spinal cord, 192. 

 chemical composition of living things, 5, 7, 42. 

 chemical compounds. Substances made of two or more chemical elements 



joined in chemical union. 



chemotropism (Eng. chemesa = chemical 4- Gr. trope a turning). Reac- 

 tion to chemical stimuli, 57. 



chiasma. The crossing of the optic nerves in the brain. 

 Chilomonas, 73. 

 chitin. A horny material, like that of which insects' wings are made. 



