EEPOET ON THE ANNELIDA. 
25 
The head is at once differentiated from that in Amphinome by the greater caruncle 
and the modification of the anterior border of the snout. Instead of the broad median 
region anteriorly there is in this form only the small rounded upper surface of the pre- 
labial folds. The caruncle is much larger than in Amphinome, and extends to tlm 
posterior border of the fourth body-segment. It is composed of a series of folds (eight 
in number), each of which is again deejDly notched in the preparation, so that it resembles 
a rope with its strands. The primary folds run from behind forward and outward, and 
are alternate with regard to the central axis. The median tentacle arises immediately in 
front of the latter, from the prominent top of the head. It is much larger than the two 
tentacular cirri which lie outside and in front of it, or than the inferior cirri which 
spring from the sides of the labial folds beneath. The eyes are two on each side, and by 
no means large. One is situated in a line with the anterior margin of the median 
tentacle ; the other has nearly the same relation to the posterior border of the organ. 
In one a third pigment-spot occurred on the left, near the base of the tentacle ] 30 steriorly. 
In the large example the anterior pair of eyes are brownish, the posterior black. The 
top of the head and the caruncle are minutely flecked with whitish grains. 
The mouth opens interiorly in the middle line between the third and fifth segments. 
The thick pre-oral folds, so well marked in some of the genera, are here comparatively 
small, and chiefly occupy the middle of the first segment. There is a decided interval 
between their posterior border and the oral aperture. The pouting masses of buccal 
tissue are softer and more rugose than in Amphinome. 
The relative difference in the size of the branchise forms a characteristic feature when 
contrasted with Amphinome ; moreover, they commence on the first bristled or body- 
segment, the first three or four being less than the others. Each tuft (when fully 
formed) consists of two main divisions, of a pale greenish colour, an outer smaller, in the 
form of a separate process immediately behind the bristle-tnft, and a larger inner arl^uscle 
which divides into several main Ijranches with short terminal processes. Three seems to 
be a common numl^er in the terminal groups. The whole organ is minutely dotted with 
white grains, which are densest on the posterior aspect of the process, and is somewhat 
dichotomously branched. The branchise are continued to the posterior extremity of the 
body, and only slightly diminished in that region. 
The dorsal bristle-tufts are distinguished from those of Amp)hinome and the others 
yet examined by their evidently alternate arrangement. So well-marked is this 
feature that at first sight the dorsal series seems to be double. The bristles are very fine 
and slender, and in this respect in strong contrast to those of Chloeia, Amiohinome, 
and Notopijgos. Their beautiful asbestos-like whiteness is also striking, as well as 
their slightly twisted appearance as they emerge from the socket, like a tuft of camel’s 
hair from the cjuill of a hair-pencil. They do not spring from a raised papdla as in 
Chloeia and Notopijgos, but emerge from a pit. Each tuft consists of a dense series of 
(ZOOL. CHALL. EXP. PART XXXIV. 1885.) LI 4 
