CONTENTS OF VOL. IV. 
Letter. Page. 
XXXVII. Internal Anatomy and Physiology of 
Insects. Sensation 1 — 33 
XXXVIII. Internal Anatomy and Physiology of 
Insects continued. Respiration . . 34 — 80 
XXXI X. Internal Anatomy and Physiology of 
Insects continued. Circulation . . 81 — 101 
XL. Internal Anatomy and Physiology of 
Insects continued. Digestion. . . . 102 — 126 
XLI. Internal Anatomy and Physiology of 
Insects continued. Secretion.... 127 — 151 
XLII. Internal Anatomy and Physiology of 
Insects continued. Reproduction . 152 — 173 
XLIII. Internal Anatomy and Physiology of 
Insects concluded. Motion .... 174 — 203 
XLI V. Diseases of Insects 201— 240 
XLV. Senses of Insects 241—264 
XLVI. Orismology, or Explanation of Terms 265 — 363 
XLVII. System of Insects 364—428 
XLVI II. History of Entomology 429—485 
XLIX. Geographical Distribution of Insects ; 
their Stations and Haunts; Seasons; 
Times of Action and Repose .... 486—527 
