EXPLANATION OF FIGURES. 
Fro. 1.—Larval Ascaris from Sagitta x60. A anus, (E cesophagus, Gi.8 blind sac 
intestine, I.S blind sac from intestine, H boring hook. 
from cesophagus, B brain, I 
Fras. 2-3.—Derogenes varicus from Sagitta x 60. 
Fic. 4.—Ditto containing eggs x 60. 
Fic. 5.—Free-swimming cercaria of Pharyngora bacillaris < 60. 
Fre. 6.—Cercaria of Pharyngora bacillaris from Sagitta x 60. O oral sucker, V ventral 
sucker, E excretory duct, E.P excretory pore, I intestine, P pharynx, VT vitellaria, 
OV ova. 
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