162 



LEECHES 



• — 14 annuli per segment; contracted specimens reveal 

 distinction between anterior and posterior body regions. 



Illinobdella Meyer 1940 

 39. Gonopores separated by 8 annuli (apparently 4 annuli 

 faintly subdivided) ; distinct seminal vesicle present. 



Illinohdella moorei Meyer 1940 



— Gonopores separated by 4 annuli (2 faintly subdivided) ; 



no seminal vesicle. Illinohdella alba Meyer 1940 



39 



40. 



41. 



42. 



Section 4. Key to the Family Hirudidae 



Jaw^s well developed, with 1 row of sharp teeth ; pharynx 

 short and very muscular; crop with many large, lobed 

 caeca 41 



Jaws reduced, with 2 rows of blunt teeth; pharynx 

 longer and less muscular; crop of adults with only the 

 posterior pair of caeca well developed 45 



Copulatory glands present behind gonopores (Fig. 13). 



Macrobdella Verrill 1872 43 



00 



XGz: 



(b) ' (c) 



Fig. 13. Diagrams of the arrangement of copulatory gland 

 pores of Macrobdella; (a) M. decora; (b) M. sestertia; (c) M. 

 ditetra. After Moore. 



Copulatory glands absent 42 



Jaws with salivary gland papillae (Fig. 14); upper Up 

 with median ventral groove (Fig. 15); diameter of 

 caudal sucker about same as maximum width of body. 



Limnatis Moquin-Tandon 



One species L. nilotica Savigny 1822 



Jaws lacking salivary gland papillae; upper Hp lacking 



median ventral groove ; diameter of caudal sucker about 



J maximum width of body. 



Hirudo L. 



One species H. medicinalis L. 



