164 



LEECHES 



47. 



XIIL 



Fig. 16. Ventral view of segments XII and XIII of Philobdella 

 gracilis showing genital pores in glandular area. 



American leech 47 



Segment VI with 3 annuli, VII with 4 annuli (Fig. 17a) 48 

 Segment VI with third annulus subdivided making 4 

 in the segment; VII having first annulus subdivided 

 making 5 in the segment (Fig. 17b) 49 



vm 



(a) (b) 



Fig. 17. Diagrams illustrating the subdivision of annuli of 

 segments VI and VII in certain species of Haemopis. The 2 

 annuli shaded in (a) are subdivided to form 4 annuli in (b). 

 {a) H. sanguisuga; (b) H. lateralis. 



48. Colour variable but usually blotched with black, brown 

 and yellowish grey; 12-16 pairs of teeth per jaw. 



Haemopis marmorata (Say 1824) 



— With a median dorsal black stripe; 9-12 pairs of teeth 

 per jaw. Haemopis kingi Mather 1954 



49. Jaws present, bearing 20-25 teeth; dorsal surface 

 usually with a median black stripe and orange marginal 

 stripes. Haemopis lateralis (Say 1824) 



