THE LEECHES (HIRUDINEA) 



659 



54 (37) Eyes three or four pairs (rarely absent), usually one or two pairs 



on II and two pairs at sides of mouth on IV; no jaws, no 

 gastric ceca; genital ducts relatively simple, with small 

 atrium produced into a pair of dorsal cornua and no penis; 

 testes numerous, not paired. Predaceous. 



Family HERPOBDELLIDAE . . 55 



55 (56) Somites strictly five-ringed, none of the annuli obviously enlarged 



or subdivided. Eyes three pairs, the first largest; genital 

 pores separated by two annuli; atrial cornua simply curved; 

 vasa deferentia reaching forward to ganglion XI. 



Herpobdella punctata (Leidy) 1870. 



The largest, best known and most widely distributed 

 member of the family in North America. The color varies 

 considerably according to the amount of black pigment 

 present. A very active leech which feeds voraciously on 

 small worms, other leeches, and aquatic insect larvae. It 

 will take human blood when opportunity offers. Egg 

 capsules found abundantly attached to stones, etc. 



FIG. 1008. Herpobdella Punctata. Atrium and neighboring parts 

 of reproductive organs, at, atrium; de, ductus ejaculatorius; 

 gXI, ganglion XI; 9 , female orifice; of, fundus of ovary; 

 ov, ovary; p, atrial horn. X 7|. (After Moore.) 



56 (55) Annulus b obviously enlarged and subdivided 57 



57 (58) Atrial cornua spirally coiled, vasa deferentia with anterior loops 



reaching to ganglion XI; eyes four pairs; genital orifices 

 separated by two annuli; colors plain or irregularly blotched. 

 Nephelopsis obscura Verrill 1827. 



FlG. 1009. Nephelopsis obscura. Dorsal and lateral aspects of atrial 

 region. X 3- (Original.) 



58 (57) Atrial cornua not spirally coiled, but short and merely curved. 



Dina R. Blanchard 1892 . . 59 



59 (62) Vasa deferentia with anterior loops reaching to ganglion XI. . 60 



Go (61) No pigmented eyes; genital pores separated by two annuli; longi- 

 tudinally striped. California. . Dina anoculata Moore 1898. 



6 1 (60) Eyes four pairs; genital pores separated by three to three and one- 

 half annuli; nearly pigmentless. . Dina parva Moore 1912. 



62 (59) Vasa deferentia not extending anterior to atrium 63 



63 (64) Eyes, three pairs; genital pores separated by three annuli; atrial 



cornua very small; pigment nearly absent. 



Dina microstoma Moore 1901. 



