Phagoaata graoilis (Haldeman, 1840) 



Synonyms: Plancwia gracilis Haldeman, 1840; Euplanaria graoilis: Kenk, 

 1930; Fontioola gracilis: Castle § Hyman, 1934; Phagocata gracilis 

 graoilis Hyman, 1945; Fontioola gracilis gracilis: Ball, 1969; Phagooata 

 subterranea Hyman, 1937; Fontioola siibterranea: Ball, 1969. 



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49 



0.5 mm 



Fig. 49 after Kenk (1970c). 



A polytypic species. Mature specimens 8^-30 mm long and 1.5-6 mm wide. 

 Head truncated with straight or slightly bulging frontal margin. 

 Generally there is a pair of rounded auricles protruding laterally, but 

 in some populations (in Virginia) these may be subdued. Color generally 

 a shade of gray or brown, darker dorsally than ventrally. In subter- 

 ranean populations the pigmentation may be almost entirely lacking. 

 Eyes normally two, supernumerary eyes occasionally seen, also eyeless 

 specimens in some subterranean habitats. Pharynges multiple. Testes 

 numerous, predominantly ventral, extending to posterior end. Vasa 

 defe entia with a characteristic backward loop before entering the penis 

 bulb. Penis with highly muscular bulb and elongated pointed papilla. 

 Below the outer epithelium of the papilla is a layer of fine fibers, 

 apparently of an elastic nature, to which longitudinal muscles coming 

 from the bulb attach. Penis lumen divided into two cavities, an anteri- 

 or nonglandular one and a larger glandular vesicle. The sperm ducts 

 open into the anterior vesicle separately or united. The ejaculatory 

 duct, of variable diameter, proceeds from the posterior vesicle to the 

 tip of the papilla. The muscle coat of the bursal stalk consists of 

 two layers, circular and longitudinal, throughout its length. For 

 differences from P. woodworthi see that species. Cocoon spherical or 

 ellipsoidal, unstalked. Reproduction only sexual. Eastern United 

 States south of the Delaware River and west to Missouri. Principal 

 literature: Peaslee (1910), Kenk (1935, 1970c), Hyman (1937a). 



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