254 P^'oceeclings of the Royal Physical Society. 



family Eudrilus and Teleuchilus, about which something 

 will be said presently. This family is, however, closely 

 connected with the Perichaetidae, through the remark- 

 able genus Anisochceta made known by Fletcher. In this 

 form, which I regard as distinct from Ferichceta, the setse 

 of the first few anterior segments are eight in number in 

 each segment; afterwards they increase until the normal 

 " perichsetous " condition is reached. This genus connects 

 the two families in the only direction in which any con- 

 nection is at all necessary. Apart from the seta3, it is 

 absolutely impossible to draw any line, however slender, 

 between the Cryptodrilidae and Perichaetidse. 



My family Cryptodrilidse does not include Eudrihts and 

 the genus Teleudrilus, quite recently described by Eosa,^ and, 

 as I think, for good reasons. 



These two genera are unique among Earthworms (1.) in the 

 structure of the female efferent apparatus; (2.) in the structure 

 of the male efferent ducts. There are also a number of smaller 

 points in which they differ from any of the Cryptodrilidaj. 



The two vasa deferentia of each side are separate up to 

 their point of opening, a character hitherto confined to the 

 Deinodrilidse and Acanthodrilidse (? as to Hoplochceta Stitarti 

 and Megascolex ceylonicus) ; they open into the upper end of 

 a structure obviously identical with the atrium of other 

 forms, though differing in many details of structure. In no 

 other case is there a connection between the vasa deferentia 

 and the upper end of atrium, except in Moniligaster (which I 

 have already seen reasons for referring to a distinct group, 

 equal to that which includes all other earthworms). These 

 atria are connected with a terminal apparatus of a remarkable 

 nature, which has its nearest analogue in the Tubificidae.^ 



^ Lombrichi dello Scioa — Ann. Mus. Civ. Geneva, ser. 2, vol. vi. (1888), 

 p. 571. 



2 All these points are more fully treated of in the following papers by 

 myself: — The Reproductive Organs in the genus Eudrilus — Proc. Roy. Soc. 

 Edin., vol. xiii., p. 672; Descriptions of some new or little known Earth- 

 worms, etc. — Proc. Zool. Soc, 1886, p. 302 ; Notes on the Ovaries and 

 Oviducts o^ Eudrilus — Zool. Anz., No. 224, 1886; Contributions to the 

 Anatomy of Earthworms — No. 1 : On the Structure of Eudrilus sylvicola 

 (Proc. Zool. Soc, 1887, p. 372); Further Notes upon the Reproductive 

 Organs of ^Mc^nV^ts— Zool. Anz., No. 293, 1888. 



