66o FRESH-WATER BIOLOGY 



64 (63) Eyes, three or four pairs; genital pores separated by two annuli; 

 atrial cornua prominent; pigment absent or in scattered flecks. 



Dina fervida (Verrill) 187 1. 



FlO. loio. Dina fervida. Reproductive organs except testes. a(, atrial cornua; de, ductus ejaculatorius; 

 iXI-XVIII, ganglia XI to XVIII; of, closed end of ovary; ov, ovary; ss, sperm sac; vd, vas deferens. 

 X ,3i- (After Moore.) 



IMPORTANT PAPERS ON NORTH AMERICAN LEECHES 



Bristol, C. L. 1899. The Metamerism of Nephelis. Journ. Morph., 15: 



17-72. 

 Castle, W. E. 1900. Some North American Fresh-water Rhynchobdellidae 



and their Parasites. Bull. Mus. Comp. Zool. Harv., 36: 18-64. 

 1900. The Metamerism of the Hirudinea. Proc. Amer. Acad., Arts and 



Sci., 35: 285-303. 

 Forbes, S. A. 1890. An American Terrestrial Leech. BuU. 111. State Lab. 



Nat. Hist., 3: 119-122. 

 Graf, A. 1899. Hirudineenstudien. Nova Acta Leop. Carol. Akad. Natw., 



72: 215-404. 

 Hemingway, Ernest E. 1908. Placobdella pediculata n. sp. Amer. Nat., 



42: 527-532. 

 Leidy, Joseph. 1868. Notice of Some American Leeches. Proc. Acad. Nat. 



Sci., Phila., 20: 229-230. 

 Moore, J. Percy. 1901. The Hirudinea of Illinois. Bull. lU. State Lab. 



Nat. Hist., 5: 479-546. 

 1905. Hirudinea and Oligochaeta collected in the Great Lakes Region. 



Bull. U. S. Bur. Fish., 25: 153-171. 

 Nachtrieb, Hemingway, and Moore. 1912. Report on the Leeches of 



Minnesota. Geological and Natural History Survey of Minnesota, 



Zoological Series No. V. Part III., Classification of the Leeches of Min- 

 nesota, by J. Percy Moore, pp. 65-150. Frontispiece and Plates I-VI. 

 Verrill, A. E. 1874. Synopsis of the North American Fresh- Water Leeches. 



Report U. S. Comm. Fish., 2 : 666-689. 



