54 MR. F. £. BEDDARD ON [Feb. 4, 



in one or both of the following characters: — (1) in the ring of setae 

 upon each segment being discontinuous at one or more points ; (2) 

 in the clitellum occupying more or fewer segments of the body than 

 three." 



Rosa has lately pointed out (24) that my distinctions are valid, 

 but that the names should be reversed. I am now quite prepared 

 to agree with him ; at the time when I wrote I was inclined to con- 

 sider that Templeton's Meyascolex was identical with Ferichceta, 

 even to the extent of having a continuous circle of setae in each seg- 

 ment, inasmuch as Baird (1), who had examined the type in the 

 British Museum, stated that he could find no difference between it 

 and Perichfeta. Taking for granted the accuracy of Baird's obser- 

 vations, it appeared to me necessary to use the name Megascolex for 

 the worms which Schmarda termed Perichreta ; strictly speaking I 

 should have allowed the name Ferichceta to drop, but it was pro- 

 posed to retain it for peiichcBtous worms with a dorsal and ventral 

 interrupted line &c. 



When I discovered (4) that my Pleurochceta was identical with 

 Templeton's Megascofea; cceruleus, it seemed necessary to restrict 

 the generic name to that form, and to group all the other known 

 perichcetous forms under the genus Ferichceta; it will be seen that 

 the definition oi Ferichceta appended to that paper includes such 

 forms as P. armata, though I omitted to state in so many words 

 that it was proposed to drop the generic distinction between Wlega- 

 scolex affinis and Ferichceta armata, since the differences between 

 Megascolex cceruleus and any other perichsetous worm are rather 

 more important than those which differentiate the latter species 

 among themselves. 



Rosa (24) has, as already stated, proposed to divide Megascolex 

 from Ferichceta by the distribution of the setge and the presence or 

 absence of intestinal cseca ; the genera are thus defined by him : — 



Megascolex. Line of setae interrupted ; no intestinal cseca. 

 Ferichcela. Line of setae continuous ; intestinal cseca present. 



Fletcher (17, iii.) has proposed a similar division, but also (17, ii.) 

 has pointed out that iu tlie typical Ferichceta, viitb continuous row 

 of setae and cseca, the gizzard is situated further back than h\ Mega- 

 scolex and occupies two segments, the mesentery between them 

 having vanished'. 



Tliis distinction, although it applies to so large a number of 

 species, falls to the ground bifore the Indian S[)ecies described by 

 Prof. Bourne^; Ferichceta hulikalensis (Bourne, 11. p. ()68) has 

 dorsal and ventral gaps, but possesses intestinal cseca in the usual 

 position. 



'■ I had previously directed (6) attention to tliis difference between certain 

 species of Perichata, though mistaken in supposing that in P. nnccomhei the 

 gizzard occupied three segments ; I have since convinced myself the gizi.ard is 

 really in segment (i ; in any case this species does not fit in very aceurateiy with 

 the jiroposed subdivision of Ferichceta. 



- This paper was overlooked bv Eosa, as he mentions in a postscript (24- 

 p. 11). 



