1919] Cort: Eggs and Miracidia of Human Schistosomes 



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the body without cilia, is constantly pushed forward and withdrawn 

 when the miracidium is moving in debris. The firm nature of this 

 papilla was shown by the way it could push aside the particles with 

 which it came in contact. 



The cephalic glands (figs. 2, 3, 4, eg) of the miracidium of Schisto- 

 soma mansoni are somewhat larger in proportion to the length of the 



ad- 



cg: 



exp 



Fig. 2. Miracidium of S. mansoni, from glandular surface; ad, anterior 

 ducts; ap, anterior papilla; eg, cephalic gland; exp, excretory pore; f, flame 

 cell; gc, germ cell; n, central nervous mass; rd, rudimentary digestive sac. 



body than in the miracidium of the other two species of human 

 schistosomes. The position of their ducts and their similarity to the 

 cephalic glands of the schistosome cercariae suggest that their secretions 

 may aid in the penetration of the miracidium into the intermediate 

 host, either by dissolving the tissue or hy neutralizing the secretions 

 of this host. The cephalic glands are unicellular, with large nuclei. 



