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Show 1892.] SPECIES OF EARTHWORMS. 701 though this seems to be perfectly similar to the arrangement figured by Michaelsen x for Notykus emini, I am inclined to think that in the latter there is a distinct sac independent of the septa. VI. Family GEOSCOLECIDAE. 15. Trichochaeta barbadensis, n. sp. I have examined a single specimen of this species which I received alive from K e w ; it is a native of Barbadoes. The worm was 24 m m . long and consisted of 84 segments; the colour during life was red, the skin containing no pigment. The setae are paired, their shape is precisely that of Trichochceta hesperidum, a new genus and species of Earthworms which I have recently 2 described from the island of Jamaica. On the clitellum the setae appeared to be rather larger than those upon the other segments of the body, and the ornamentation at the tip a little more pronounced. Although the setae in the present species show no trace of the characteristic irregularity of Trichochceta hesperidum, I do not hesitate to place them in the same genus on account of the peculiar form of the setae, which is unmatched in any other Oligochaet. At first one would be inclined to regard the irregularity of the setae as a mark of generic distinction; but it must be borne in mind that in Pontoscolex, as was first pointed out by Fritz Miiller 3, and I have been able to confirm his discovery, the setae are occasionally regular and paired. The clitellum, exceptionally for the family Geoscolecidae, is complete; that is to say, there is no ventral tract free from glandular tissue. Rosa has used the saddle-shaped clitellum as one of the characters of the Geoscolecidae; the present species shows that this character can be no longer used. The clitellum extends from the xiiith segment to the xxiind. The prostomium appeared, before the worm was examined by means of sections, to resemble that of Rhinodrilus or Trichochceta hesperidum, that is to say it lay apparently in the mouth instead of projecting above it. In longitudinal section, however, this appearance is seen to be largely due to the retraction of the prostomium, which is perhaps facilitated by the division of the first segment into two annuli by a groove. The nephridia are paired, the first pair being rather larger than those which follow: the large size of the first pair of nephridia is commonly found to be a character of the Geoscolecidae ; it is hardly so pronounced in the present species as in Pontoscolex for example. The duct of this nephridium is long and appears to open on to the exterior on the third segment. As to the vascular system, the only point that I particularly note is the presence of a pair of large hearts in each of segments x., xi. 1 " Beschreibung der von Herrn Dr. Fr. Stuhlmann auf Sansibar &c," JB. Hamb. wiss. Anst. ix. 2 Q. J. M. S. Jan. 1893, p. 252. 3 " Description of anew Species of Earthworm," Ann. & Mag. Nat. Hist. ser. 2, vol. xx. p. 13 (translated from a paper in the Arch. f. Naturg.). P R O C ZOOL. Soc.-1892, NO. XLVII. 47 |