226 CLASS VII. 
Sp. Nephelis vulgaris, Hirudo octoculata L., Encyclop. méthod., Vers. Pl. 51, 
figs. 5—7; Sturm, Deutschl. Fauna vi. 2 Heft; Jonnson, Phil. Trans. 
1817, Pl. tv. (reprinted in his Further Observat. on the Leech, 1825); this 
species swallows small worms. 
Trocheta Dutrocuet, Trochetia Lam. (Geobdella Buainy. in part). 
Branchiobdella Optnr. Body somewhat depressed, with large 
rings, not numerous. ‘Two horny jaws. Eyes none. 
Sp. Branchiobdella astaci OptER, Mém. de la Soc. d@ Hist. nat. de Paris 1. 
1823, pp. 69—78, Pl. tv. (already observed and figured by RoEsEL, Jns. 111. 
Pl. urx. figs. 1g—221); Branch. parasita, comp. HENLE, Ueb. die Gattung 
Branchiobdella, MUELLER’S Archiv. 1835, 8. 574, &c. Taf. Xv. 
Hirudo L. (exclusive of several species). Body oblong, sub- 
depressed, with numerous rings. Three horny jaws. Eyes usually 
ten. 
Bdella Sav. Jaws not denticulate. Eyes eight. 
Sp. Bdella nilotica Sav., GuéRin, Iconogr., Annél. Pl. 4, fig. ro. 
Hemopis Sav. Maxille armed with a double row of denticles not 
numerous. Eyes ten. 
Sp. Hemopis sanguisorba, Hirudo sanguisuga L., Encyclop. méth., Vers. 
Pl. 51, figs. 3, 4, black, grey-green beneath; this species is larger than the 
common Leech. Commonly two species have been here confounded, 
which Moguin-Tanpon places in two different genera: Aulastoma (Hir. 
sanguisuga MuELL., Hir. Gulo Braun, Sturm, Deutschl. Fauna vi. 2) and 
Hemopis (Hir. sanguisuga BERGM., L.) 
Sanguisuga Say. Jaws armed with a double row of denticles 
very slender and crowded. yes ten. 
Sp. Hirudo medicinalis L., Hirudo venesector BRAUN, SturM, Deutschl. 
Fauna vi. 2 Heft; BRANDT u. RatzeBurG, Mediz. Zool. 1. Taf. XXvIt. 
figs. 3, 4; Guérin, Zconogr., Annél. Pl. 10, fig. 3; above, blackish-green, 
with six long stripes spotted reddish and black, beneath olive-coloured with 
many black spots (four to five inches long), Another species, Hér, officinalis 
Sav., is also used for medicinal purposes, which is yellowish beneath with 
a broad black edge, without spots, see BRANDT u. Rarzes. 1. 1. Taf. xxx. 
fig. 1; J. J. Knouz, Naturhist. Abhandl. ueber die Blutegel, Wien, 1820, 
1 This genus must by no means be confounded with Branchiobdellion Ruv., Bran- 
chellion SaviGNy, which like Clepsine and Nephelis has no jaws, but only three project- 
ing points ; if the semicircular little plates on the same part of the body be really gills, 
as Savicny says, (CuvrER doubts and Moqurn-TaNnDon denies it,) then it does not 
belong to this order. LAaTREILLE places it near the genus Arenicola. 
