ZOOLOGY OF FEET^'ANDO NOROITnA. 



561 



colour, somewhat like that of Limlricus terrestris ; it measured 

 5 1 inches ; the fifth turned out to be merely the anterior portion 

 of a similar specimen. 



The Worm A. — The first feature which struck me was the 

 quincuncial arrangement of the setsein the posterior region of the 

 body ; anteriorly the setae are in couples. 



The body-wall, being somewhat transparent, allowed me to 

 distinguish through it paired light-coloured bodies, or " pyriform 

 sacs," lying in the ventral region posteriorly. The most 

 anterior somite of the body is very elongate, and carries the 

 mouth terminally, the prostomium being absent. These features 

 recalled the genus UrocJiceta of Perrier ; but somewhat similar 

 characters are found in other Earthworms : thus the pyriform 

 sacs have been described by myself in Urohenus * ; and the scat- 

 tered condition of the setae, though not identical with the arrange- 

 ment noticed, closely resembled, and might easily be confounded 

 with, what obtains in Diachceta (Benham). 



Turning then to the clitellum, I found it to cover the somites 

 xiY. to XXII. or XXIII. ; it is not complete on the ventral surface ; 

 and both anteriorly and posteriorly is, as is often the case, 

 more feebly developed. One peculiar feature, however, about 

 the clitellum, which therefore recalled Urochcdta, is the fact 

 that the intersegmental grooves are deep and noticeable; the 

 glandular structure not being continuous from somite to somite, 

 as is the case in most other Earthworms. 



I could see no pores, or external apertures, of the genital ducts 

 or nephridia ; I therefore opened the worm, in the ordinary way, 

 by a median dorsal incision, in order to satisfy my suspicion as 

 to its belonging to the genus Urochceta, 



The septa are thin, with the exception of four situated anteriorly, 

 which are greatly thickened, namely those forming the posterior 

 wall of somites yi., yii., yiii., and x. (the septum between ix. and x. 

 is absent). Such thickened muscular septa are not unusual in 

 Earthworms ; but whether their position is constant in a given 

 species is by no means certain. Perrier has not helped us to 

 settle the matter, since in liis figure he represents only four such 

 septa, whereas in the text he speaks of five of them. However, 

 Beddard t, in a species of this geiuis from Aust ralia, describes four, 

 having the same position as in the worm under consideration. 



^ Quart. Journ. Micr. Sci. vol. xxvii. 



t Proc. Roy. Soc. Edinb. xiv. 1887, p. 160. 



