ABRANCIIIA. 



3L'9 



The Leeches {Ilinido, Linn.) — 

 Have an oblong body, sometimes depressed, and wrinlded transversely ; tbe mouth encircled by a lip, 

 and the posterior extremity furnished with a flattened ilisk, both ends Ijeing adapted to fix upon bodies 

 by a kind of suction, l)y means 

 of which these animals move, 



for, having fixed their anterior /^^il^M^Sff^^^^^^i^^^^^MW!S'SiH&0^ S'l \ —'?-=-'?" 

 extre»iity. tliev draw tbe other fJSwSi \\ ' '\ ' ' > '>'i'''ii iii' 'i \y'\\w^'\" ''^if^''^ ^1%^''--- '^h'^' 

 up to it and tix tliat, and then i ^X^lS^ _^'^'''^ '"^ ' — ^ i AV-^- iin-. n '. -r^ *^^*"^ yM^^^J-'j^^^ 



readvauce tbe first, [Ijesides 

 which, they swim Avith facility]. 

 Several have a double series of r-B. 2(i;.-nir»(io omtin«ii, ; o, ii> a„icr„jreiirt,niiy, ihc>.i„s ii,e .acker. 



pores underneath tlie body, whieli are the orifices of little internal pouches, considered by some natu- 

 ralists as organs of resinration, although they are generally filled with a mucous fiuid. The intestinal 

 canal is straight and swoln at intervals, extending for two thirds the length of tbe body, where there 

 are true C03ca. The blood they swallow continues red, and without alteration, for several weeks. The 

 ganglia of their nervous system are much more separated than those of the Earthworms. They are 

 hermaphrodite, and have a large penis about the anterior third of the body, and a vulva a little behind 

 it. Several accumulate their eggs into cocoons enveloped by a fibrous excretion. 



[On opening the Leech shortly after it has gorged itself with the blood of its prey, it will be found 

 that none of the blood has passed into tbe intestines. The operation of digestion is extremely slow, 

 notwithstanding the rapid and excessive manner in which the Leeeli fills its stomach; a single meal 

 of blood will sufiiee for many months, nay, more than a year will sometimes elapse before tbe blood 

 has passed through the intestines in the ordinary niannei-, during all which ])eriod so much of tbe 

 blood as remains undigested in tbe stomach continues in a fluid state, and as if just taken in, notwith- 

 standing the vast difl'erenee in the heat of tbe body of a mamniLferous animal and that of a Leech.] 

 — Griffith, An. King., part 35, p. 129. 



They are subdivided upon characters derived principally from the organs of tbe mouth. In 



The Leeches, properly so called [San- 



guhurja, Sav.), — 

 Tbe anterior sucker has the lip divided into 

 several segments ; its aperture is trans- 

 versal, and contains three jaws, each armed 

 with a double range of very fine trenchant 

 teeth, which enable them to pierce the 

 skin without inflicting a dangerous wound ; 

 Fi 1-te p mc.it o/Hirucio meHicinniit. thcyhave tcn minutc points, which have 



been considered as eyes. 

 Every one is .icquaintcd ivith the medicinal Leech (//. mcUchudis, Linn.), so useful an instrument for loc&l 



bIood-letfin|f. 



li^MOcis, Sav., — 



Differs by having the teeth less numerous and comparatively obtuse. 



Such is the common Horse Leach, (H. sanguhorba, Sav.). 



Bdellia, Sav., — 

 Has only eight eyes, and no teeth whatever. 



There is one in the Nile (Brf. nilotica, Egypt. Ann.) 



Nephelis, Sav., — 

 Has also but eight eyes, and the mouth with only three folds of the skin interiorly. 

 M. de Blainville terms them BrpobddUs, and M. Oken Ilelluo. 



Ndmerous small species inhabit our fresh waters, among which should be distinguisl et"- 



Trochetia, Untroebet, — 

 Which differ by having a bulge at the genitals. 

 A species (Gcobdella trocheiii, Blainv.), is often seen upon the ground, pui'suing the Earthivorms. 



