180 
The British Leeches 
Distribution, Pood, etc. This species is widely distributed in 
Europe and very common in the British Islands, in running and stag¬ 
nant water, upon the muddy bottom, beneath stones and among aquatic 
plants. It breeds from May to October and its dark brown, transparent 
egg-capsules are 4—6 mm. long and 2—4 mm. wide and attached at 
each extremity to the stalks of aquatic plants and other submerged 
foreign bodies. 
This and the succeeding species devour small Oligochaetes such as 
Tubifex, Planarians (Moquin-Tandon) and probably a variety of other 
soft-bodied aquatic animals. Bristol (1898) fed the N. American 
H. lateralis , in confinement, upon “ chopped fresh-water clams.” 
Herpobdella atomaria, Garena, 1820. 
Plate XV, Fig. 45. Text Fig. 15. 
Synonymy and Literature : 
Hirudo atomaria, Carena, 1820, p. 295, pi. xii, fig. 16. 
Nephelis atomaria, Moquin-Tandon, 1826, p. 128, pi. vi, fig. 6; R. Blanchard, 1892 a, 
p. 165, figs. 1—4; R. Blanchard, 1893 b, p. 4, figs. 1, 2. 
Hirudo ( Erpobdella) atomaria, de Blainville, 1827, p. 261, pi. xxxvi, fig. 5. 
N. octoculata, var. atomaria, Moquin-Tandon, 1846, p. 304, pi. iii, fig. 7. 
N. reticulata, Malm, 1860, pi. iii, fig. 7. 
N. scripturata, Schneider, 1885, p. 129 (see R. Blanchard,’ 1893 d, p. 195). 
N. crassipunctata, Schneider (see R. Blanchard, 1893 e, p. 197). 
Herpobdella atomaria, R. Blanchard, 1894 b, p. 56, figs. 18—22. 
Diagnosis. Body closely resembling H. octoculata in form, usually 
fulvous or greenish brown, paler and unicolorous ventrally. 
Dorsal surface, except at the anterior extremity, with a series of 
reddish or yellowish white spots on every ring and generally with a 
black reticulated pattern. The first ring of each somite is rendered 
conspicuous by the accentuation of the yellowish white spots, which are 
often fused into a transverse band, and by the absence of black pigment. 
Somites I—IV uniannulate, V and XXV usually biannulate but 
sometimes triannulate owing to the subdivision of the second ring, 
XXVI and XXVII biannulate; the 18 somites VI—XXIII complete 
with five rings. Somite XXIV usually quadri-, sometimes quinque- 
annulate owing to subdivision of the last ring. 
The male genital orifice is situated between the fourth and fifth 
ring or upon the fifth ring of somite XI; the female orifice lies between 
the second and third ring or upon the third ring of somite XII. These 
