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Show 164 MR. F. E. BEDDARD ON WORMS [Feb. 16, no reasons either for believing or disbelieving that Vaillant's Perichceta cingulata is the same species as Schmarda's Perichceta cingulata. In the specimens which I examined there is no trace of the natural colour left; the worms are a pale brownish grey-the clitellum a darker brown. As they do not agree with any Perichceta of which there is an adequate description, I give them the new name Perichceta taprobance. There are only four species of Perichceta which agree with the present in possessing only a single pair of spermathecae, so that it is more easily to be discriminated than species which possess the more typical number of three or four pairs. The species in question are Perichceta sangirensis, Mich.1, Perichceta ceyfonica, F. E. B.2, Perichceta quadrayenaria, E. P., and Perichceta elongata, E. P. Perichceta taprobance differs from the last two species in a number of points ; it will be sufficient here to mention one point of difference only for each species. Perichceta taprobance differs from Perichceta quadra-genaria in the size and form of the spermathecal appendix; from Perichceta elongata in the characters of the " prostate" ; from Perichceta sangirensis in the absence of a dilated sac at the distal extremity of the atrium. Perichceta ceylonica is distinguished by having two pairs of atria. Perichceta taprobance is a stout worm, measuring about 80- 100 m m . ; the largest specimen was 105 m m . in length; an individual measuring 84 millims. in length had a breadth of 6'5 mm. and was composed of about 114 segments. The worm undoubtedly belongs to the restricted genus Perichceta, although, as will be seen presently, one of the distinctive characters of the genus is absent : the setce form continuous rows and are numerous ; on the first setigerous segment of one specimen I counted 52 setae, on the fifth 81, on the twelfth segment of the same individual there were 74, on the twenty-fifth 67. The seta formula is therefore as follows :- Segment I. V. XII. XXV. 52 81 74 67 The setae are present on all the clitellar segments and form complete circles. Their form is not different from that of the setae elsewhere. Those upon the hinder segment of the body are nearly twice as long as those upon the anterior. The clitellum is composed of the usual three segments, but is a little indistinct at both ends. _ The oviducal pore is single and median; it lies in front of the circle of setae of segment xiv. The atrial pores are upon the xviiith segment and are sometimes very prominent-forming conical elevations-owing to a protrusion 1 " Oligochaeten des naturhistorischen Museums in Hamburg, IV.," Jahrb. Hamburg, wiss. Anst. viii. p. 35. 2 "Notes on some Earthworms from Ceylon and the Philippine Islands &c " Ann. & Mag. Nat. Hist., Feb. 1886. * |