CHAPTEE IV 



ARRANGEMENT OF INTERNAL ORGANS MUSCLES NERVOUS SYSTEM 



GANGLIONIC CHAIN BRAIN SENSE-ORGANS ALIMENTARY 



CANAL MALPIGHIAN TUBES • RESPIRATION TRACHEAL 



SYSTEM FUNCTION OF RESPIRATION BLOOD OR BLOOD- 

 CHYLE DORSAL VESSEL OR HEART FAT-BODY OVARIES — 



TESTES PARTHENOGENESIS GLANDS. 



The internal anatomy of Insects may be conveniently dealt with 

 under the following heads: — (1) Muscular system; (2) nervous 



w -u. 



Fig. 63. — Diagram of arrangement of some of the internal organs of an Insect : a, mouth ; 

 5, mandible ; c, pharynx ; d, oesophagus ; e, salivary glands (usually extending 

 further backwards); /, eye; (/, supra - oesophageal ganglion; ^, sub-oesophageal 

 ganglion; i, tentorium; 7, aorta; k^, k^, ^3, entothorax ; Zj-^gj ventral nervous 

 chain ; m, crop ; 11, proventriculus ; 0, stomach ; ^J, Malpighian tubes ; q, small 

 intestine ; r, large intestine ; s, heart ; t, pericardial septum ; «, u^ ovary composed 

 of four egg-tubes ; 1', oviduct ; w, spermatheca (or an accessory gland) ; x, retractile 

 ovipositor ; y^ cercus ; s, labrum. 



system ; (3) alimentary system (under which may be included 

 secretion and excretion, about which in Insects very little is 

 known); (4) respiratory organs ; (5) circidatory system ; (6) fat- 

 body ; (7) reproductive system. 



