386 / C. O. WHITMAN. 
7th to the 9th ganglia. The left oviduct passes under the 
nerve-chain, just the reverse of what happens in H. nipponia. 
The common oviduct (od. c.) and the gland (gl. alb.) adhere to 
the saccular portion of the vagina. 
Habitat.—Ditches and ponds around Tokio and Yezo. 
None found at Aomori. Much less abundant than the 
common Medicinal Leech. 
Habits.—Very sluggish ; not easily induced to swim, though 
swimming well when forced. Food unknown; probably car- 
nivorous. 
LEPTOSTOMA EDENTULUM, g. et sp. nov. Pl. XIX, figs. 28—389. 
Diagnostic Characters. 
Body.—Small, tapering gradually to the very narrow head 
(figs. 28 and 29). 
Length, swimming, 5°5 cm.; in extension, 7°5 cm.; abreast, 4°5 cm. 
Width a Teme * 6 mm.; » 910mm, 
The largest individual found measured, in extension, 12 cm. ; 
swimming 8°5 cm. 
Cephalic lobe and anterior portion of body extremely 
narrow. 
Acetabulum 4 mm. in diameter. 
Annuli 105, with sometimes a rudiment of a 106th behind 
the anus. 
Buccal annuli = 5th and 6th, united on the ventral side. 
Post-buccal annuli= 7th and 8th, united on the ventral 
side. 
Genital Apertures.—Male orifice between 32nd and 
33rd annuli—two annuli behind the fourth pair of nephridial 
pores. Female orifice between 37th and 38th annuli. 
Clitellum 9th, 10th, and 11th somites. 
Anus cuts the 105th annulus. 
Ocelli five pairs, as in Hirudo. 
(Esophagus has six folds, one dorsal, one ventral, two 
dorso-lateral, two ventro-lateral. 
Maxillz three, very small, only a little higher than the 
