THE HIRUDIN E A OF GEORGIAN BAY 175 



SESSIONAL PAPER No. 39b 



Piscicola punctata, Verrill. 



In size these specimens vary from 15 to 30 mm. in length and from 2 to 3mm. 

 in greatest diameter. The form is rounded and slender, and the division of the body 

 into anterior and posterior portions is evident. The suckers are slightly explanate 

 but do not exceed the body in diameter nor are they so deeply cupped as in P. 

 milneri. The separation of the suckers from the body is not so well defined as in 

 most Piscicolas. 



In these specimens one pair of eyes has been observed but the number of an- 

 nuli in a complete somite has not been determined. 



At about the anterior end of the middle third of the body is an area covering 

 apparently seven annuli. This area has a more or less swollen, porous appearance 

 and contains the genital pores. This region evidently answers to the description of 

 a clitellum, although a distinct clitellum is described as absent in this family 

 (Moore, 1912). 



An examination of a dissected specimen reveals the presence of a protrusible 

 proboscis, an oesophagus and a moniliform crop. Attached at the base of the pro- 

 boscis are a number of whitish bodies irregular in shape and provided with long 

 white "ducts". These are, in all probability, the diffuse salivary glands. Attached 

 to the oesophagus about midway is a pair of bodies which resemble the oesophageal 

 glands of Placobdella montifera. 



The ovaries appeal in the form of two elongated sacs. There are five pairs of 

 testes. Attached in the region of the "clitellum" are four thick layers of tissue just 

 beneath the layer of longitudinal muscle. These bodies, probably the clitellar 

 glands, pass backward toward the posterior end of the body. 



These specimens were found clinging to rock bass (Amhloplites rupestris). 



BIBLIOGRAPHY. 



1899. Bristol, C. L. — The Metamerism of Nephelis. Journal of Morphology, vol. XV. 



1900. Castle, W. E. — Some North American Fresh- Water Rhynchobdellidse and their Parasites, 

 Bull. Mus. Comp. Zool, vol. XXXVI, No. 2. 



1898. MooRE, J. Percy. — The Hirudinea of Illinois. Bull. III. State Lab. Nat. Hist., vol. V. 



1905. Moore, J. Percy. — Hirudinea and Oligochaeta Collected in the Great Lakes Region. 

 BuU. U. S. Bur. Fish., Vol. XV. 



1899. Moore, J. Percy. — The Leeches of the U. S. National Museum. Proc. U. S. Nat. Mus., 

 vol. XXI. 



1912. MooRE, J. Percy. — The Leeches of Minnesota. Geological and Natural History Survey 

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1872. Verrill, A. E. — Synopsis of North American Fresh-water Leeches. Rep. U. S. Fish Comm. 

 (Refers to Amer. Journ. Sc, vol. III). 



1891. Whitman, C. O. — Description of Clepsine plana. Journal of Morphology, vol. IV. 



