112 



A. CI. Bourne — On cerfain Earthworms from the [No. 1, 



setas, but is closely approximated to tlie posterior extremity ; the part of 

 the seta which lies behind the dilated region is straight. The general 

 shape of these clitellar setaa, apart, of course, from the bifid extremityi 

 is like that of imperfectly developed ordinary setro. That this is not 

 really the case with these setfe is, however, clearly shown by the fact that 

 all the setfe of the several rows comprised in the clitellum have precisely 

 the same shape, and also by the fact that in two specimens of the worm, 

 which were the first that came to hand, the structure of these clitellar 

 setfe was precisely identical." 



The ordinaiy petfe present also some variations in size. The seta 

 immediately on either side of the median ventral line is usually if not 

 always larger than the others. The setfe on the clitellar somites in 

 my specimens agree with the minute desci'iption quoted above. 



Perrier states that the gizzard occupies somite IX, but I have found 

 that the septa separating somites VIII — IX and IX — X are absent, so 

 that the gizzard may be said to occupy somites VIII, IX, X. This is 

 the position ascribed to the gizzard in P. fees., P. indioa, P. peregrina, 

 and is moreover its probable position in P. sieholdi, P. japonica, P. 

 musica, and P, anniilata. These are all worms possessing other special 

 characters in common, and further investigation will probably add to the 

 list P. affinis, P. hirmanica, P. sumatrana, P. hasselti, P. rnbusta, P. 

 aspergillum, P. quadragenaria, P. elongata, P. schmardce, P. capensis, and, 

 possibly, P. ^ueenslandica and P. darnleionsis. 



The organs described by Perrier as testes are doubtless seminal 

 reservoirs ; in position and structure they agree with these organs in so 

 many other worms. 1 have not, however, been able to find the true 

 testes, btit could doubtless do so in fresh specimens. The spormathecce 

 and prostates have been described and figured by Perrier. I have 

 figured them in PL III, Figs. 4 and 5. The number, position, and struc- 

 ture of the spermathecfe have been largely used as specific characters. 

 The structure of the prostate glands is a character of no less specific 

 importance. 



Typhous masoni, sp. n. 



External characters. — Length 130 m.ni. ; width 6 m.m. Prosto- 

 mium is short and broad and can be retracted so as to be hidden by the 

 first or buccal somite. The latter is but very slightly marked oft" from 

 the second somite and is as usual devoid of setfe. The other prc-clitellar 

 somites consist of two, three, or oven four annuli. 



The clitellum when fully developed extends complotoly round the 

 body in somites XIV, XV, XVI, nearly the whole of XVII, and a small 

 portion of XI II. 



