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Show . ' 468 ANNELlDES. tlll'ee folds of skin. Several small species are found in the stagnant waters of France; it is thought proper to distinguish from them the TROOHETIA, Dutroch.(l) Which only differs from them in an inflation at the spot where the genital organs are placed. One species is found in France-Geobdella trochetii, Blainv., Diet. des Sc. Nat., Hirud., pl. IV, f. 6, which frequently leaves the water in pursuit of Lumbrici. M. Moquin-Tandon, under the name of AuLASTOMA, even describes a subgenus, where the mouth is merely furnished with numerous longitudinal plicre-.8ulast. nigrescens, Moq. Tand., pl. vi, f. 4. Immediately after the N ephelides come the BRANOHIOBDELLA, Odier, remarkable for their two jaws and the absence of eyes. One species is known which Jives on the branchire of the Astaci(2). In all these subdivisions the anterior sucker is but slightly sepa· rated from the body; in the two following ones it is clearly dis tin· guished from it by a strangulation, i3 composed of a single seg· ment, and has a transverse orifice. In the H.lEMOOHARis, Sav.(3) In addition to this conformation, there are eight eyes, a slender body, and but slightly U.istinct rings. The jaws are salient, and scarcely visible points. The Hremochares do not swim, but walk like the caterpillars called Geometrre, and adhere particularly to fishes. One species, Hirudo piscium, L.; Rresel, III, xxxii, is fre· quently observed on the Cyprini( 4). The HELLuo. Such are: Hir. vulgaris, L., or H. octoculata, Dergm., Stock., Mem., 1757, pl. vi, f. 5-8;-N. atomaria, Caren., L., c, pl. xii. See also pl. vi of Moquin· Tandon. (1) M. de Dlainville changes this name to GEoBDELLA. (2) Brancltiobdella .!J.staci, Od., Mem. de la Soc. d'Hist.• Nat. de Paris, t. I, pl. iv. (3) M. de BI_ainville, who had named them PrscrcoL~, a name adopted by La· marck, has agam changed it to ICTHYOBDELLA. (4~ ~dd, Piacicola cephalota, Caren., pl. xii, f. 19, and Moq. Tand., pl. :vii,f, 21 -Pzsctc. tesaelata, Moq. Tand., f, 3. I ) I ABRANCHIAT.£. 469 ALBIONA, Sa v. ( 1) Differs from the preceding subgenera in the booy, which is studded with tubet·cles, and in having six eyes. The Albionre inhabit the Ocean. r t .O.lb. muricata; Hirudo muricata, L. A very abundant species in the seas of Europe; it is covered with small tubercles(2). There is a parasitic animal that lives on the Torpedo called Bru.NoHELLION( 3) which closely resembles a Leech in its two cups, de~ p1·essed body and transverse plicre. Its anterior cup, which appears to have a very small mouth in the posterior margin, is placed on a narrowed portion resembling a neck, at the root of which is a small bole for the organs of generation; there appears to be another behind. The Iate1·al edges of its plicre, which are compressed and salient, have been considered as branchire, but I can find no vessels there; its epidermis is ample, and the envelope like a very loose sac(4). We also commonly place among the Leeches the CLESPINE, Sav.-GLossoPORA, Johns.(s) The Clespines have a widened body, a posterior cup only, and a probosciform mouth witl~ut a sucker; some of them, however, may be found to belong to the family of the Planarire(6). I consider them more closely allied to the PnYLLINE, Oken(7), and to the MALAooBDELLlE, Blainv.(8), which also have broad bodies, and are deprived of a proboscis and anterior sucker. They are parasitic animals. (l) The PoNTOBDELL.J£, Leach and Blainv. (2) Adu, Pontobdella areolata;-Prmt. verrucata;-Prmt. spinulosa, Leach, Zool. Miscel., lxiii, lxiv, lxv;-Hirudo vittata, Chamiss., and Eisenhardt, Nov. Act. Nat. Cur., t. X, pl. xxiv, f. 4. (3) The PoLYDORA, Oken; BnANCHIOBDELLION, Rudolphi; and the BnANcnxon· DELLA, BlaiJw. (4) It is the Branchellion torpedinis, Sav., but it must not be associated with the species found on the Tortoise (Hir. branchiata, Menzies, Lin. Trans., I, xviii, 3), which really appears to hl\ve branchia: that resemble a branch of feathers, and which it is requisite again to examine. (5) The GLossonnELLiE, Blainv. (6) HirudJJ complanata, L., or sexoculata, Bergm., Stock. Mem., 1757, pl. vi, f. 12-14;-Hir. trioculata, lb., f. 9-11;-Hir. hyalina, L., Gm., Trembley, Polyp., pl. vii, f. 7;-Clespine paludoaa, Moq. Tand., pl. iv, f. 3, &c. (7) EPIBDELLM, Blainv. ;-Hir. hippogloa8i, Mull., Zool. Dan., liv. 1-4. (8) Hir. grossa, Mull., Zool. Dan., xxi. |