PLATK II. 



Lill.l'IIK Kl'llili, Sp. 11. 



Km. 1. Ventral view of the anterior end of <>ne <if tin- smaller specimens, magnified, and showing the 

 month, cephalic slits, proboscis-pore, and the groove forming a " V >: irmuediately in front of 

 the mouth. 



Kir;. 2. Transverse section towards the middle of the body. B.S., blood-sinus; C.M., circular muscle- 

 layer ; D.N., dorsal nerve ; D.V., dorsal blood-vessel ; <>!., glandular \ayer of the integument ; 

 Int., intestine ; L.M 1 ., inner longitudinal muscle-layer : L.M 2 ., outer longitudinal muscle-layer ; 

 L.N., lateral nerve-stem ; N.P., nerve-plexus : P.S., cavity of proboscis-sheath. 



KIG. :'. Portion of the outer part of the body-wall in transverse section, highly magnified. B.M., 

 (secondary) basement-membrane ; C.M-., layer of circular muscle-fibres : C.T., connective tissue 

 strands; Ep., external epithelium: <!!.. glandular layer ; Gl 2 ., gland-cells of the epithelium; 

 L.M 2 ., outer longitudinal muscles. 



Fin. 4. Transverse section immediately behind the brain. B.8., blood-sinus : C.C., cerebral canals ; 

 C.M., circular muscle-layer; C.O., cerebral organ ; D.N., dorsal nerve; 1>.V., dorsal blood- 

 vessel ; GL, glandular layer ; L.M 1 ., inner longitudinal muscle-layer ; L.M 2 ., outer longitudinal 

 muscle-layer ; L.N., lateral nerve-stem passing outwards from the brain : P.S., cavity of 

 proboscis-sheath ; V.B.8., ventral portion of blood-sinus. 



Fin. 5. Transverse section through the middle region of the body of a female specimen. B.8., blood- 

 sinus ; C.M., circular muscle-layer ; D.Y., dorsal blood vessel ; G., gonadial sac, tilled with 

 ova; Int., intestine ; L.M 1 ., inner longitudinal muscle-layer ; L.M 2 ., outer longitudinal muscle- 

 layer ; P.S., cavity of proboscis-sheath. 



FIR. 6. Transverse section through the proboscis, highly magnified. C., C., points where the circular 

 muscle fibres cross each other dorsally mid ventrally ; X., longitudinal nerves. 



