44 



HIRUDINEA 



4. Transverse section through a Leech under low power. Epidermis ; alimentary canal ; connective 

 tissue and muscles of the body ; dorsal sinus ; ventral sinus enclosing the nerve-cord ; lateral vessel ; 

 fine capillary branches of vascular system ; nephridia ; vas deferens ; unicellular glands dipping into 

 body muscles from the epidermis ; longitudinal muscular fibres ; external circular muscular fibres ; 

 dorso-ventral muscles. 



5. Sections from the anterior extremity to show the eyes and special sense organs. 



