PLATE XXII 



FIG. I. Linens rubescens Coe. Transverse section of head in front of brain, 

 showing distribution of cutis glands {cugT), the highly developed cephalic glands 

 (cgT), and the duct (a) leading forward beneath the rhynchodaeum (r/t). This 

 duct is probably the common efferent canal for the secretions of the more pos- 

 terior cephalic glands ; cf, cephalic furrow ; bl, blood lacuna ; COT, circular muscles. 

 X8o. 



FIG. 2. Carinella frenata Coe. Portion of transvers c ection of head, show- 

 ing the deep ciliated pit (cp) from which a ciliated sensory canal (cc) leads inward 

 to the brain region, where it becomes surrounded with sensory nerves (sn) from 

 the dorsal side of brain to form a highly specialized sense organ ; i, integument; 

 jfi, layer of fibrous connective tissue surrounding brain ; cm, circular muscles ; 

 br, fibrous core of brain, surrounded except internally by a thick layer of nerve 

 cells ; bm, basement membrane. X 6- 



FIG. 3. Carinella frenata. Portion of transverse section of body through 

 lateral sense organ; /, integument, sharply contrasted with the layer of special- 

 ized sensory cells lining the sensory pit; In, lateral nerve; Iv, lateral blood 

 vessel ; se#, epithelium of stomach ; icm and ocm, inner and outer circular mus- 

 cular layers ; Im, longitudinal muscles. X 60. 



FIG. 4. Tetrastemma bilineatum Coe. Portion of transverse section of body. 

 The two pigment bands ( $ig) which give the body its characteristic markings 

 are situated in the midst of the longitudinal muscles (/*), on either side of the 

 proboscis sheath (re] ; iae, intestinal epithelium ; other reference letters as in 

 fig, a. X 230. 



(220) 



