42 Dr. W. B. Benham on some Javan Perichetide. 
six segments or so the white chetigerous ring is interrupted, 
and each cheta or two or three chate lie in a white patch; 
moreover, on these segments the bands extend further and 
further ventralwards, till on the first three segments they meet 
ventrally, though the depth of colour ts slightly less here than 
on the dorsal surface. On the clitellum these bands, though 
faint, are still recognizable. 
Unfortunately Dr. Willey did not inform me of the true 
colours of the living worm; and no doubt the colours will 
soon fade in spirit. 
A somewhat similar banding occurs in P. pulchra*, from 
Luzon, and P. pictust, from Borneo; but in both these 
species the dark bands are intersegmental. ‘The anatomy, 
moreover, is quite distinct. In P. annulatus, Horst ft states 
that the worm is “blackish, with a white ring round the 
middle of each segment.” But in these three cases no 
mention is made of the light intersegmental ring. 
In P. Willeyt the chete form practically a complete circle, 
but the median dorsal space is about twice the length of the 
ordinary intersetal spaces ; and across this space there is fre- 
quently a dark line joining the dark transverse bands; so that 
the worm appears to have a darker longitudinal median 
stripe along its back. ‘The ventral cheete are somewhat closer 
together than the dorsal ones ; there is no ventral gap. The 
number of cheete is 54 on the thirty-fifth segment, 48 on the 
nineteenth, 44 on the twelfth, 28 on the second. 
The prostomium is small and not dovetailed; but as the 
buccal region is everted, it is difficult to be positive on this 
point. The limits of segments i. and ii. quite distinct. 
The clitellum is confined to the three segments xiv., xv., 
xvi., and has very distinct limits. 
The first dorsal pore is between segments xii. and xiii. ; 
there are none on the clitellum, nor are chet present here. 
The male pores are very evident, slightly oblique, curved 
slits surrounded by a prominent margin, which is anteriorly 
crenate, but posteriorly rounded and more projecting (as in 
P. operculata, where, however, the “ operculum” is formed 
by the anterior lip). Surrounding the projecting margin or 
lips is a circular area reaching to the boundaries of the 
segment. There are ten chete between the male pores. 
The oviducal pore is median and distinct. There are two 
* Michaelsen, “ Terricol. d. Berliner Zool. Sammlung,” Arch. f. Natur- 
gesch. 1892, p. 25. 
+ Ibid. p. 38. 
t ‘Notes from the Leyden Museum,’ y. 
