Procotyla fluviatilis Leidy, 1857 



Synonyms: Vendroooelwn superbum: Leidy, 1851 (not Girard, 1850); D. 

 laateum: Woodworth, 1896 (not 0. F. Miiller, 1774); D. graffi Wilhelmi, 

 1909; ?D. pulaherrimum Girard, 1850; lOligooelis pulahervima: 

 Stimpson, 1857. 



88 



89 



0-5 mm 



vdc pp gp 



Mature animals 12-20 mm long and 2-5 ma. wide. Head truncated, rather 

 variable in shape during locomotion. Subterminal adhesive organ 

 clearly visible in living animal, bulging out slightly during gliding, 

 flanked by two rounded auricular projections with a constriction or 

 neck behind them. Eyes of variable number, in the northern distribu- 

 tional area 1-8 on either side, in the sourthem states usually only 1. 

 The groups of eyes are rather far removed from each other, by about 1/2 

 the width of the head. Testes numerous, dorsal, extending posteriorly 

 to level of copulatory complex. Vasa deferentia unite at the level of 

 the penis and enter the penis bulb anteroventrally as common vas 

 deferens. The penis consists of an elongated muscular bulb with a large 

 cavity and a short conical papilla. The bulb is composed of several 

 layers surrounding the cavity: an outer, very thick layer of longitudi- 

 nal muscles, a fibrous layer, an inner layer of chiefly longitidinal 

 muscle fibers (in P. typhlops these are circular) , and the glandular 

 epithelial lining of the cavity or prostate. The common vas deferens 

 runs along the ventral wall of the penial cavity and connects with it 

 at the base of the penis papilla. Beyond this junction the lumen con- 

 tinues into the penis papilla as ejaculatory duct and opens at its tip. 

 The common oviduct and the outlet of the sac-shaped copulatory bursa 

 open close to the gonopore. Cocoon ellipsoidal, unstalked. The species 

 refuses liver or Tubifex as food but takes living amphipods, isopods , 

 and aquatic insect larvae. Inhabits ponds, lakes, streams and springs 

 in the eastern part of North America, from Maine to Louisiana and west 

 to Ontario, Wisconsin, and Illinois. Principal literature: Woodworth 

 (1897), Hyman (1928), Kenk (1944). 



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