INDEX 



Frog, reproductive organs of, 144 

 respiratory organs of, 142 

 skeleton of, 146 

 skin of, 138 

 spinal cord of, 146 



Grasshopper, 70 



Heart of bird, 186 



of clam, 268 



of crayfish, 28 



of earthworm, 254 



of fish, 124 



of frog, 142 



of grasshopper, 80 



of rabbit, 208 



of turtle, 162 

 Hemiptera, 96 

 Honey bee, 90 

 House fly, 92 

 Hydra, 234 



Insect case, 52 



net, 56 

 Insecta, 52 

 Insecticides, 68 

 Insects, collecting, 54 



field trip, 58 



life-history of, 62 



spraying of, 66 



sprays for, 66 

 Instincts, altruistic, 14 



egoistic, 14 



Kidneys of bird, 192 



of clam, 268 



of crayfish, gg, Fig. 1, 38 



of earthworm, nephridia, 258 



of fish, 124 



of frog, 144 



of rabbit, 214 



of turtle, 168 

 Killing bottle, 54 



Lungs of bird, 186 

 of frog, 142 

 of rabbit, 214 

 of turtle, 168 



Mammalia, 200 

 Man, 222 

 MoUusca, 260 

 Mussel, 260 



Nutrition of coelenterata, 236 

 of porifera, 230 

 of protozoa, 226 



Orthoptera, 70 



Pisces, 112 

 Porifera, 230 

 Protozoa, 226 



Rabbit, 200 



arteries of, 208 



circulatory organs of, 208 



digestive organs of, 210 



ears of, 202 



excretory organs of, 214 



eyes of, 202 



field study of, 200 



heart of, 208 



kidneys of, 214 



limbs of, 206 



locomotion of, 20<) 



mori)hology of, 202 



nervous system of, 218 



reproductive organs of, 214 



respiratory organs of, 214 



skeleton of, 214 



skin of, 206 



systematic study of, 21S 

 Reptilia, 152 



Scales, ctenoid, 116 

 cycloid, 116 

 of bultcrflv, 88 



