GLOSSARY 209 



Branchial : relating to the gills. 



Branchial heart : a lateral heart in the squid, 129. 



Branchiate : bearing gills. 



Branchiostegite : a paired lateral fold of the body-wall in crustaceans, 30. 



Brood-sac : a chamber in which the eggs develop in certain crustaceans ; 



sow-bug, 47 ; amphipod, 49 ; Daphnia, 57. 

 Bud : an outgrowth of an animal which becomes a new individual ; Bugula, 



87; Hydra, 161; hydromedusan, 166, 172, 177. 



Calcareous : formed of carbonate of lime. 



Capsulogenous glands : glands of uncertain function, but which may aid in 



the secretion of the cocoon in the earthworm, 69. 

 Carapace : the shell covering a portion or all of the cephalothorax in 



crustaceans ; crayfish or lobster, 29 ; crab, 42 ; larval decapods, 51. 

 Cardo : the basal division of the maxilla in insects, 13. 

 Cellulose : the woody cell-wall of plant cells ; Molgula, 135 ; Euglena, 193. 

 Cephalothorax : a body-division formed by the fusion of the head and the 



thorax in arthropods ; spider, 24 ; crayfish or lobster, 28 ; crab, 42 ; 



larval decapods, 51 ; copepod, 53. 

 Cercus : a paired projection at the posterior end in certain insects, 10. 

 Cheliped : the large grasping claw in many crustaceans, 30. 

 Chitin : a hard and very resistant substance present in the cuticula of 



arthropods. 

 Chloragogue cells : glandular cells surrounding the digestive canal of the 



earthworm, 71. 

 Chlorophyll : the green coloring matter of plants, 192. 

 Chromatophores : pigment bodies ; squid, 123 ; Hydra, 160. 

 Cilia : the numerous vibratory projections on the outer surface of certain 



animals ; planarian, 76 ; Paramecium, 185 ; Vorticella, 188 : and of 



certain organs ; Bugula, 86 ; mussel, 94 ; clam, 108. 

 Cirrus : a filamentous, sensory appendage of annelids, 62, 63 : a protrusile, 



copulatory organ of flatworms, 77. 

 Clitellum : a thickened glandular region on the earthworm which secretes 



the cocoon, 68. 

 Cloaca : a tubular or sac-like space which receives the discharge of various 



organs ; planarian, 77; tapeworm, 83 ; mussel, 92 ; clam, 106 ; snail, 121. 

 Clypeus : a median sclerite in the face of insects just back of the upper 



lip, 12. 

 Cnidoblast: a stinging cell in Cnidaria which contains the nematocyst; 



Hydra, 161; tubularian, 165; campanularian, 171. 



