Dr. Johnston’s Index to the British Annelides. 44) 
Un ver plat et blanc, Tremb. Polyp. 147. pl. 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. 
pl. 1. fig. 20. 
Piscicola. 
Piscicola, Lam. Anim. s. Vert. 2nde edit. v. 525.—Hzmocharis, 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. pl. 1. fig. 1-8. 
Hirudo piscium, Mull. Verm. i. ii. 43. Penn. Brit. Zool. iv. 70. pl.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. Perce. 
Ichthyobdella Perce, Templeton in Loud. Mag. N. Hist. ix. 236. 
fig. 28. 
3. P.marina. Plate XV. fig. 4-6. 
Hab. 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 circular 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, 
Obs. 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. 
Pontobdella. 
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.u.357. Penn. Brit. Zool. iv. 71. pl. 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. i. 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. 1. 49. 
