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Show 158 MR. F. E. BEDDARD ON A [Feb. 15, distinguished the clitellar from the ordinary setae ; moreover I have frequently found even in mature examples that the clitellar setae of both dorsal and ventral pairs only showed slight traces of ornamentation at their free extremity ; such setas alternated in the most irregular fashion with setas like that displayed in the drawing (fig. 3) ; they are, however, of equal size. Dorsal pores appear to be entirely absent. The only apertures besides the mouth and anus recognizable on the exterior of the body are those of the nephridia, which are placed in front of the dorsal pair of setae close to the anterior margin of the segment (fig. 2 ) ; these apertures were especially plain upon the clitellum. Vascular System.-In none of my specimens was the vascular system very well preserved. The dorsal vessel (fig. 4, d) runs close to tbe surface of the gizzard, and near to the hinder end of that organ gives off two pairs of slender trunks (h) to the ventral vessel (v). After this the dorsal vessel runs some way above the surface of the oesophagus, and is not directly connected with the ventral vessel; segments 10, 11, and 12 contain each a pair of lateral "hearts" (h), Chief Trunks of Vascular System. d, the dorsal vessel; v, ventral vessel; s, supraintestinal; h, anterior "hearts" connecting dorsal and ventral vessel; h', posterior hearts connecting supraintestinal and ventral vessel. of which the two anterior pairs are considerably stouter than the pair ; these are given off from the supraintestinal trunk (s), which is of some thickness in these segments. I could not detect any additional communication with the dorsal vessel, and am inclined to think that there is none. Alimentary Canal.-The mouth-aperture, as already stated, is terminal, and in all my specimens was excessively minute ; the buccal cavity is thick-walled and very narrow, with an almost imperceptible lumen. The pharynx is large, and is followed by a wide thin-walled oesophagus. The oesophagus is remarkable for the fact that it does not pass straight to the gizzard, but is bent upon itself, forming a loop : it might be readily imagined that this condition is simply due to the contraction produced by the preservative reagent; but I found the same condition of the oesophagus in all the specimens that I dissected, and in all of these the gizzard was apparently retracted |