ABRANCHIATE. 145 



Immediately after the Nephelides come the Branchiobdella, 

 Odier, remarkable for their two jaws and the absence of eyes. 



One species is known which lives on the branchiae of the 

 Astaci =■-. 

 In all these subdivisions the anterior sucker is but slightly sepa- 

 rated from the body; in the two following ones it is clearly distin- 

 guished from it by a strangulation, is composed of a single segment, 

 and has a transverse orifice. In the 



H^MocHARis, Sav.\ 



In addition to this conformation, there are eight eyes, a slender 

 body, and but slightly distinct rings. The jaws are salient, and 

 scarcely visible points. The Hsemochares do not swim, but walk 

 like the caterpillars called Geometrae, and adhere particularly to 

 fishes. 



One species, Hirudo piscium,Ij.; Rcesel, III, xxxii, is fre- 

 quently observed on the Cyprini J. The 



Albion A, Sav.^ 



Differs from the preceding subgenera in the body, which is studded 

 with tubercles, and in having six eyes. The Albionae inhabit the 

 Ocean. 



Alb. muricata ; Hirudo muricata, L. A very abundant spe- 

 cies in the seas of Europe ; it is covered with small tubercles ||. 



There is a parasitic animal that lives on the Torpedo called Bran- 

 cheluonII, which closely resembles a leech in its two cups, depressed 

 body, and transverse plicae. Its anterior cup, Avhich appears to have 

 a very small mouth in the posterior margin, is placed on a narrowed 

 portion resembling a neck, at the I'oot of which is a small hole for the 

 organs of generation ; there appears to be another behind. The 

 lateral edges of its plicae, which are compiessed and salient, have 

 been considered as branchiae, but I can find no vessels there ; its epi- 

 dermis is ample, and the envelope like a very loose sac**. We also 

 commonly place among the Leeches the 



♦ Branchiobdella Asfaci, Od., M^va. de la Soc. d'Hist. Nat. de Paris, 1. 1, pi. iv. 

 t M. de Blaiaville, who had named them PiscicoL.5, a name adopted by La- 

 marck, has again changed it to Icthyobdella. 



I Add, Piscicola cephalota, Caren., pi. lii, f. 19, and Moq. Tand,, pi. vii, f. 2; — 

 Piscic. tesselafa, Moq. Tand., f. 3. 



§ The PoNTOBDELL^, Leach and Blainv. 



II Add, PontobdeUa areolata ; — Pont, vcrrucaia ; — Pont, spinulosa, Leach, Zool. 

 Miscel., Ixiii, Ixiv, Ixv ; — Hirudo vittata, Chamiss., and Eisenhardt, Nov. Act. Nat. 

 Cur., t. X, pi. xxiv, f. 4. 



^ Tlie PoLYDORA, Oken; Bkaxchiobdellion, Rudolphi ; and the Branchiob- 

 della, Blaiuv. 



** It is the BranchelHon torpedinis, Sav., but it mustnot be associated with the 

 species found on the Tortoise {Hir branchia'a, Meazies, Lin. Trans., I, xviii, 3), 

 which really appears to have branchiae that resemble a branch of feathers, and 

 which it is requisite again to examine. 



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