DESCRIPTIONS OF GENERA AND SPECIES 381 



This species is quite exceptional in the genus Megascolex in having paired nephridia. 

 It may prove to be rather referable to Perionyx, which is chiefly to be characterized 

 by its paired nephridia and lobate spermiducal glands. 



(a8) Megascolex coxii (Fletcher). 



Perichaeta eoxu, Fletcher, Proc. Linn. Soc. N. S. "Wales (a), vol. i, 1886, p. 565. 



Definition. Length, igo mm.; diameter, gmm. Setae as many as ^o per segment posteriorly. 

 Clitellum, XIII-XVII. Dorsal pores commence XIII/XIV. Eight pairs of genital pores on 

 segments in front of and behind the eighteenth. Calciferous glands, 6 pairs in VIII-XIII. 

 Last heart in XIII. Sperm-sacs in XI, XII. Spermathecae in Fill, IX, with short caecum. 

 Spermiducal glands extend through nine segments. Hah. — Mt. Wilson, N. S. Wales. 



See also Fletcher (5). 



(39) Megascolex attenuata (Fletcher). 



Perichaeta attenuata, Fletcher, ibid. (2), vol. iii, 1888, p. 1552. 



Definition. Length, 100 mm.; diameter, 3 mm.; number of segments, 220. Setae, 28 per 

 segment in posterior fourth of body. Clitellum, XIII-XVII. Male pores on XVII. 

 Dorsal pores commence XII/XIII. Calciferous pouches, six pairs in VIII-XIII. Last hearts 

 in XII. Sperm-sacs in IX, XII. Spermathecae iti, VIII, IX ; pyriform pouches, with 

 a single, club-shaped caecum. Spermiducal glands extend through three segments. Hab. — 

 Mt. Wilson, Australia. 



(30) Megascolex enormis (Fletcher). 



Perichaeta enormis, Fletcher, ibid., p. i555- 



Definition. Length, 87 mm.; diameter, 4 mm,; number of segments, 220. Setae not more than 



16 per segment in posterior region of body. Dorsal pores commence X/XI. Male pores 



XVII/XVIII ; between each two segments from XV/XXII a pair of genital papillae. 



Spermathecae (in VIII, IX?) each with two small caeca. Hab. — Near Gosford, 



N. S. Wales. 



The setae appear to be sinuously arranged on the posterior segments of the body ; 



sometimes ' they alternate irregularly for some distance.' Along with this peculiarity, 



to which I have referred above in the sketch of the genus, is another, viz., that the 



setae are implanted on conspicuous ridges, ' giving the body a more perichaete 



appearance.' 



