W. A. Harding 
177 
clitellum, well marked during the breeding season, extends from the second 
ring of somite X to the second ring of somite XIII, inclusive. 
The two species, H. octoculata and H. atomaria, which represent this 
genus in the British Islands have constantly been confused. The latter 
species generally has been considered to be merely a variety of H. octo¬ 
culata and has shared in its synonymy. The synonymy of H. atomaria 
has been here given as far as it could be ascertained, but a number of 
references which may apply indiscriminately to either species will be 
found under H. octoculata. 
Herpobdella octoculata, Linnaeus, 1758. 
Plate XV, Figs. 42—44. Text Fig. 14 (p. 179). 
Synonymy and Literature: 
Hirudo tenuior et a cauda muris non multum diversa, Aldrovandus, 1602, p. 722. 
Hirudo octocidata, Bergman (partim), 1756, p. 199; Bergman (partim), 1757, pi. vi, 
figs. 5—8 ; Linnaeus (partim), 1758, p. 649; Linnaeus (partim), 1761, No. 2080; 
Weser, 1765, p. 44; Linnaeus (partim), 1767, p. 1079; Turton, 1806, p. 69; 
Turton, 1807, p. 129; Blumenback, 1807, p. 432; Pennant, 1812, p. 71; 
Blumenbach, 1825, p. 244; Derheims, 1825, p. 10. 
Hirudo vulgaris, O. F. Muller (partim), 1774, p. 40; O. F. Muller (partim), 1776, 
p. 220; Gmelin, 1788, p. 3096; Bruguikre, 1791, pi. li, figs. 5—8; Bose, 1802, 
p. 256; Schrank, 1803, p. 161; Braun, 1805, p. 39, pi. iii, figs. 4—11 (coloured); 
Johnson, 1816, p. 33; Johnson, 1817, p. 21, pi. ix; Stewart, 1817, p. 356; 
Carena, 1820, p. 290; Johnson, 1825, p. 29, pi. ix. 
Nondescript Leech , Ure, 1793, p. 236. 
Helluo ( Hirudo ) octoculata, Oken, 1815, p. 367. 
Erpobdella vulgaris , de Blainville (partim, in Lamarck), 1818, p. 296; Fleming, 1822, 
p. 604 ; (not Delle Chiaje, 1823, p. 49); de Blainville (partim), 1828, p. 564, 
pi. xxxvi, figs. 4 and 4 a—4 i; Milne-Edwards (in Lamarck), 1835, p. 528 ; Egidy, 
1844, p. 134, fig. 64; Johnston, 1846, p. 439; Thompson, 1856, p. 425 (in 
Ireland); (not Verany, 1846). 
Nephelis tessellata, Savigny (partim), 1822, p. 117. 
Nephelis testacea, Savigny, 1822, p. 117; de Filippi, 1837. 
Nephelis tessulata, Risso (partim), 1826, p. 431. 
Nephelis vulgaris, Moquin-Tandon (partim), 1826, p. 125, pi. vi, figs. 4, 5 ; de Filippi, 
(partim), 1837, p. 28 ; Brightwell, 1842, p. 13, pi. i, figs. 9—14 (egg-capsules); 
Leydig, 1849 b; Diesing (partim), 1850, p. 456; Grube, 1851, p. 110; Robin, 
1865, p. 5 et seq. (embryology) ; Hertwig, 1877, p. 2 et seq. (embryology) ; 
Hoffmann, 1880 (embryology); Schneider, 1880, pjr. 19 and 256 (embryology); 
Jijima, 1882, p. 12 (ovary and egg-strings) ; Bergli, 1884, p. 284, pis. xviii and 
xix (development); Filatow, 1898, p. 645 (embryology); Graf, 1899, p. 224 
