REPORT ON THE ANNELIDA. 
409 
body, except that a Crustacean parasite was attached to the fifteenth segment Ijy two small 
processes on the under surface of the snout. There are four segments behind the buccal, 
each with strong simple spines and tufts of bristles. Some of the bristles are furnished 
with a distinct wing on each side, while others are simple, slender, tapering structures. 
The rows of hooks commence at the fifth segment. They present three well- 
marked teeth above the great fang (PL XXXIXa. fig. 1), the throat under the latter 
being only very slightly hollowed out, much less than in Maldanella antarctica, to 
which, however, the shape is somewhat allied. There is a ]3rominent posterior shoulder. 
No food existed in the alimentary canal. 
The tube has a whitish appearance, and is composed almost entirely of Diatoms, 
massive reticulated structures, probably Radiolarian, and the slender cylindrical spicules 
formerly alluded to. It is slightly friable, but by no means brittle, even when the 
tough hyaline lining is removed. 
A characteristic feature in the transverse sections of this abyssal form is the great 
thickness of the cuticle. The hypoderm is also of considerable bulk, and the circular 
coat is well marked. The longitudinal ventral muscles exceed the dorsal in area, and 
are not much tapered superiorly. The nerve-area (PI. XXXVIIa. fig. 5) has passed 
upward, so that it lies between the ventral longitudinal muscles, and even projects 
within them, so that the oblique muscles appear to be attached to the projecting angles 
of the nerve-mass. The circular muscular layer is indistinct in this region in the pre- 
parations, but appears to form no appreciable boundary on the inner border of the area. 
Fraxillinicola kroyeri, n. gen. and sp. (PI. XXXIXa. fig. 10). 
This Crustacean parasite consists of nine segments. The body of the female is about 
2 '5 mm. in length, narrow and elongate. The cephalo -thorax is somewhat shield-shaped, 
its transverse diameter, however, considerably exceeding its antero-posterior. The only 
differentiation this region presents is its central projection or rostrum on the anterior 
ventral margin, and the two short processes, which probably represent a pair of antennae, 
by which it adheres to its host. The abdomen has two dilated segments anteriorly, 
followed by four somewhat narrower ones. A narrow segment occurs in front of the 
rounded posterior end, which presents a central genital aperture. So far as could be seen 
through the opaque whitish body, the central region was occupied by the ovaries, which 
contained numerous ova. The description of the Doniisa clymenicola of Nordmann^ has 
not been available, but in the elongate form of the body the new species approaches the 
Rhodinicola elongata of Levinsen,^ a form found on Rhodine loveni. It differs, however, in 
the absence of the post-abdomen, and in the rudimentary condition of all the appendages. 
^ Stated by Levin sen to be in the Bull, cle I’Acacl. St. Petersburg, 1864, but which is not. 
2 Vidensk. Meddel. f. d. nat. Foren. i Kj^benhavn, 1877, p. 360, Taf. vi. figs. 1-4. 
(ZOOL. CHALL. EXP. PART XXXIV. 1885.) 
LI 52 
