Ih'. Johnston^s Index to the British Annelides. 441 



Un ver plat et blanc, Tremb. Polyp. 147. pi. 7. fig. 7. 

 Hirudo hyalina, Mull. Verm. i. ii. 49. Stew. Elem. ii. 357. 

 Clepsina hyalina? Brightwell in Ann. and Mag. Nat. Hist. ix. 15. 

 pi. 1. fig. 20. 



Piscicola, 



Piscicola, Lam. Anim. s. Vert. 2nde edit. v. 525. — Haemocharis, Sa- 

 vigny. (See Ann. and Mag. N. Hist. ix. 11.) 



1. P. geometra. 



Hirudo geometra, Linn. Syst. 1080. Turt. Gmel. iv. 70. Turt. Brit. 



Faun. 129. Johnson on the Med. Leech, 35. Brightwell in Ann. 



and Mag. N. Hist ix. 11. pi. 1. fig. 1-8. 

 Hirudo piscium, Mull. Verm. i. ii. 43. Penn. Brit. Zool. iv. 70. pi. 21. 



fig. 3. Stew. Elem. ii. 357. 

 Piscicola piscium. Lam. Anim. s.Vert. 2nde edit. v. 525. Stark, Elem. 



ii. 142. 

 Piscicola geometra, Flem. Phil. Zool. ii. 604. 



2. P. Percee. 



Ichthyobdella Percae, Templeton in Loud. Mag. N. Hist. ix. 236. 

 fig. 28. 



3. P. marina. Plate XV. fig. 4-6. 



Hah. Parasitical on the Aspidophorus cataphractus. 



Desc. Body one inch in length and a line in diameter, slightly tapered 

 forwards, terminated at each end with a plain tn'rcular sucker, of a uniform 

 chestnut-brown colour, or red and mottled (for the colour varies according 

 to the intestinal contents), smooth, rather soft and compressed ; the margins 

 minutely crenulate under a magnifier. 



Fig. 4. P. marina of the natural size. 5. The same magnified. 6. An out- 

 line figure drawn from an individual which had the genital organs extruded. 



Ohs. Mr. W. Thompson has, in his Catalogue of the Irish Worms, 

 a Piscicola marina (Rep. p. 272), but no description of it has been 

 published. 



Pontohdella. 



Pontobdella, Leach in Suppl. Encyclop. Brit. i. 451. Lam. Anim.s. 

 Vert. V. 293. 



1 . P. muricata. 



Hirudo piscium. Bast. Opusc. Subs. i. 82. tab. 10. fig. 2. 



Hirudo muricata, Linn. Syst. 1080. Turt. Gmel. iv. 71. Turt. Brit. 



Faun. 130. Stew. Elem.ii. 357. Penn. Brit. Zool. iv. 71. pi. 21. 



fig. 4. Johnson on the Med. Leech, 38. Dalyell in Edin. New 



Phil. Journ. 1827, p. 391. Grant in Edin. Journ. of Science, 



no. 14. 

 Hirudo verrucosa, Fleming in Wern. Mem. ii. 245. Johnson on the 



Med. Leech, 39. 

 Pontobdella muricata. Lam. Anim. s.Vert. v. 293; 2nde edit. v. 524. 



Stark, Elem. ii. 142. Templeton in Loud. Mag. N. Hist. ix. 236. 

 Albione muricata, D. Chiaje, An. s.Vert. Nap. i. 49. 



