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Show 1892.] OF THE GENUS PERICHCETA. 163 There are two pairs of receptacula ovorum in segments xiii.l and xiv. respectively. Those of segment xiii. lie above the ovaries. The three pairs of spermathecce lie in segments vi., vii., and viii. The oval pouch of the spermatheca has a long narrow duct: the diverticulum has the same form but is much smaller; it is hardly as long as the duct of the main pouch. PERICHCETA TAPROBANCE, n. sp. The following description is based upon the examination of some half-dozen examples of a Perichceta from Ceylon. The specimens were collected a good many years ago by Prof. Moseley and were deposited by him in the Oxford University Museum. Mr. W. Hatchett Jackson was so good as to place them in my hands for identification and description. The worms were labelled " Perichceta cingulata" and I presume therefore that they agreed with Schmarda's coloured figure of that species2. As, however, Schmarda's description of the species is not by any means sufficient for identification, I do not think it safe, in the present state of our knowledge of this genus of Earthworms, to define any species by colour only. M . Vaillant3, to whom we are indebted for the first anatomical account of Perichceta, identified six Earthworms in the Paris Museum with P. cingulata, apparently basing this identification upon the shape of the setae. The futility of such a character is shown by the fact that Perrier * was rightly able to distinguish several distinct species among the individuals which were all called "Perichceta cingulata " by Vaillant. The name " cingulata " was applied by Schmarda in the belief that the species was characterized by possessing a clitellum. It is not, however, on this ground that I think it desirable to drop the name Perichceta cingulata altogether. Vaillant's Perichceta cingulata according to PerrierD is practically indistinguishable from the Perichceta posthuma of the same author ; and it is impossible to be certain that they are different from Perrier's Perichceta affinis-so at least Prof. Perrier thinks, and Dr. Horst6 agrees with him. But I do not follow Perrier in retaining the name Perichceta cingulata for Perichceta posthuma, since there are really 1 Fletcher (" Notes on Australian Earthworms, Part III.," Proc. Linn. Soc. N. S. W . ser. 2, vol. ii. p. 394) describes in Perichceta canaliculata " a pair of smooth white sacs "lying above the ovaries in segment, xiii., which are doubtless the same structures. Two pairs of these bodies occur in several species of Perichceta. 2 ' Neue wirbellose Thiere,' Bd. ii. p. 16, pi. xviii. fig. 162. 3 " Note sur l'Anatomie de deux Especes du Genre Perichceta, &c," Ann. Sci. Nat. 5e ser. t. x. p. 225. 4 Loc. cit. 6 Loc. cit. p. 114. 6 " Descriptions of Earthworms, V.," Notes Leyden Mus. vol. xii. p. 232. It should be remarked, however, that Vaillant neither figures nor describes setae upon the clitellum; he remarks, indeed, " la ceinture seule en [des soies] est privee." They are present in Perichceta affinis, so that probably Dr. Horst's earlier (Midden-Sumatra, Vermes, p. 4) identification of P. cingulata (of Vaillant) with Perichcsta indica was more correct. |
