PHILIPPINE POLYCLAD TURBELLARIANS. 



637 



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to a certain degree as two somewhat lighter colored streaks. The 

 ventral surface was a little paler than the dorsal. 



Completely round the margin of the body are numerous small 

 eyespots which form a crowded row. In addition to these there is 

 a large number of eyespots scattered over the anterior end of the 

 body, extending back as far as the brain, where they are thickly set. 

 Further, some eyespots 

 form a crowded cluster on 

 each side of the brain which 

 apparently represent a ten- 

 tacular group of eyes. 



The genital organs are 

 constructed on the same 

 plan as in 0. toahlbergi. 

 The vasa deferentia, pro- 

 ceeding straight backward, 

 turn abruptly round at 

 near the male gonopore 

 and then pursue a directly 

 opposite course, to enter the 

 base of the penis, without 

 forming any seminal ves- 

 icle, differing to that ex- 

 tent from G. ivahlbergi in 

 which the seminal vesicle 

 is formed on either side. 

 Within the penis bulb they 

 unite into a common duct, 

 the ejaculatory duct, which 

 opens into the anterior part 

 of the penis sheath near the 

 tip of the penis. Embedded 

 in the penis bulb, just pos- 

 terior to the ejaculatory 

 duct, is the prostate, which 

 is a small pear-shaped or- 

 gan and opens near the 

 apex of the penis together 



with the ejaculatory duct. The penis is of conical shape and projects 

 downward into a cavity, whose walls form the penis sheath. This 

 cavity opens directly to the exterior by the male gonopore which lies 

 a little behind the pharyngeal cavity. 



The female gonopore occurs a short distance posterior to the 

 male and leads into a narrow irregular antrum, which in turn is 



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