CONTENTS. 



I. 



Frog. 



General characters — Development — Specific characters of Rana tern- 

 poraria and R. esciilenta — Splanchnic (pleuro-peritoneal) cavity and 

 the organs of the viscera — Neural cavity and the cerebro-spinal axis — 

 Comparison of transverse sections across the head and trunk — General 

 comparison with Lobster and Crayfish — Skeleton — Digestive system — 

 Lymph and blood vascular systems — Heart — Respiratory organs and 

 respiration — Urinogenital system — Ductless glands — Nervous system — 

 Sense organs and integument — Laboratory work . . pp. i — 172. 



II. 



Fresh-water Crayfish and Lobster. 



Habitat — General structure — Exoskeleton and appendages — Diges- 

 tive system — Circulatory system and heart — Respiratory system — Excre- 

 tory organs — Nervous system and sense organs — Reproductive organs — 

 Development — Ecdysis — Laboratory work. . . pp. 173—239. 



III. 



Earthworm. 



Habitat — General external characters — Exoskeleton and setoe — Di- 

 gestive system — General structure of body wall and alimentary canal — 

 Body cavity and mesenteries — Excretory system — Circulatory system — 

 Neurosensiferous system — Reproductive organs — Development — Clitel- 

 lum — Laboratory work. ...... pp. 240 — 271. 



