no. 3638 TURBELLARIA — KAWAKATSU 9 



secretions of which pass into the bulbar cavity. Often the penis lumen 

 and the male antrum are packed closely with this heavily eosinophilic 

 granular secretion. The two sperm ducts enter the bulbar cavity from 

 the anterolateral sides of the penis bulb separately. 



The penis papilla has a symmetric conical shape when well extended 

 but varies according to the degree of contraction. The outer wall of 

 the penis papilla is lined with a flat epithelium, under which there are 

 two muscle layers, a layer of circular fibres below the epithelium, and 

 a layer of longitudinal fibres. 



A slight morphological difference was noted in comparing the present 

 new subspecies and Phagocata n. nivea. The new subspecies has a 

 symmetric conical papilla with the opening of the penis lumen on its 

 tip (fig. 3). The penis lumen of Phagocata n. nivea, however, opens 

 ventrally at the tip of the papilla (Kenk, 1953, pp. 164-168, fig. 21). 

 Kenk also notes that in "Phagocata nivea the penis lumen opens 

 usually below the tip of the papilla" (p. 168). 



b s cod v 



sv sd be ma PP c< 3 



Figure 3. — Sagittal view of copulatory apparatus of Phagocata nivea tahoena. 



The copulatory bursa, which is situated in the usual position, is a 

 large sac with somewhat irregular outline (fig. 3). The cavity of the 

 bursa is fined with a very tall and thick glandular epithelium. In the 

 lumen of this organ, in several worms examined, a mass of sperm 

 was found enveloped in a coagulum of the secretion. The bursa stalk, 

 a wide duct surrounded with a strong muscular coat consisting of 

 intermingled circular and longitudinal fibres, runs posteriorly to the 

 left of the midline, and curves ventrally to open to the common antrum 

 (fig. 3). The posterior terminal part of the bursal canal becomes 

 wide and forms the well-developed vagina. Numerous eosinophilic 

 glands open into the common antrum near the genital pore. 



