Smith. — Notes on Neiu Zealand Earthworms. 133 



cases 'reserve setae,' more or less immature, and to the num- 

 ber of two, were present in addition to the fully-formed and 

 functional setae. The setae are implanted so as to divide the 

 circumference of the body into four areas ; the distance, how- 

 ever, between the ventral pairs is less than that between the 

 dorsal and ventral pair of one side, and the distance between 

 the two dorsal pairs. The arrangement of the setae, therefore, 

 in P. smithii brings the genus nearer to the Lumbriculidce, 

 where there are four rows of pairs of setae. Another point 

 in which P. smithii differs from the other species of the 

 genus is in the shape of the setae. In both the other species 

 the shaft, the portion implanted in the body-wall, is straight : 

 in P. smithii this is not the case ; the setae are bent through- 

 out, and have the shape so characteristic of the setae of the 

 Oligochceta. 



"Absence of Genital and Pcnial Setce. — It is important to 

 put on record the fact that in the neighbourhood of the repro- 

 ductive apertures there is no modification whatever of the 

 setae. It is not possible to state with absolute certainty that 

 Phreoryctes has no genital setas, but it is at least highly pro- 

 bable that this is the case. This, again, is a point which 

 bears upon the affinities of the genus. Most Oligochceta show 

 some modification of the setae on the genital segments, but 

 this is apparently not so with, e.g., the Lumbriculidce, which 

 family Phreoryctes resembles in other particulars. 



" Clitellum. — In the majority of my specimens the clitel- 

 lum was developed. The position of the clitellum in the 

 genus has not been hitherto known, and, as this organ is of 

 some little importance in the classification of Oligochceta, it is 

 particularly desirable to have some information upon the point. 

 The clitellar region was obvious, in all the specimens which 

 had reached that degree of maturity, by its swollen, distended 

 appearance and whitish colour. The swollen appearance and 

 the white colour are, however, due not so much to the modi- 

 fication of the integument in this region of the body as to the 

 mass of generative products, principally spermatozoa, which 

 are developed in these segments, and cause them to be con- 

 siderably distended. The comparatively slight increase of 

 thickness in the epidermis of the clitellum, as compared with 

 the epidermis over the general body-surface, is not sufficient 

 to distinguish this part of the body when examined without 

 the aid of a microscope. When the body is slit open, and the 

 integument examined microscopically, the extent of the cli- 

 tellum is quite obvious ; it extends over three complete seg- 

 ments and the part of a fourth. The posterior boundary of 

 the clitellum coincides with the furrow separating segments 

 xiii.-xiv. Anteriorly the clitellum is not so sharply defined ; 

 it commences on segment x., at or near the setae. The clitel- 



