SEASONAL IMI-0 \T10N WITH LARVAL \ KM.VI < >l >L>. 503 



narrow intestinal ccca, tr.icraliK- only in serial sections, reaching 

 almost to excretory vesicle. One pair of prominent larval gland 

 ducts, with granular contents, on either side of body, mistaken 

 by Linton for excretory vesicles; four large eosinophilic larval 

 glands, staining also with intra-vitam neutral red, but clearly 

 observable only in sections. Large excretory vesicle, much 

 constricted posteriorly, and surrounded by a sphincter muscle; 

 opening in center of adhesive disc. A few flame cells observed, 

 but exact pattern of excretory system obscured by numerous 

 refractile globules distributed throughout body. Future repro- 

 ductive system represented by a number of cell groups; two 

 spherical masses, just posterior to ventral sucker, probably 

 testes, with female complex anterior to excretory vesicle. Inch- 

 worm locomotion of this species effected by successive attach- 

 ment of posterior end of body, modified by invagination into an 

 adhesive disc, then extension of body and attachment by ventral 

 sucker. 



Cercarixum lintoni is obviously different from C. dentali, C. 

 giardi, and C. crispata of Pelseneer (1906), and from the five 

 species described by Lebour (1912) in character of the digestive 

 and excretory systems, or in the parthenita. 



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 Alice, W. C. 



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