REPORT ON THE ANNELIDA. 
369 
which under a moderate power (PI. XXXVIa. fig. 6) show externally a translucent 
investment of connective tissue, and internally a highly refractive, globular body often 
split into two or more divisions, and resembhng a fatty mass. A distinct capsule 
surrounds the refractive body. The abundance of these on the vessels indicates their 
functional value. The walls of the vessels are further provided with granular cells and 
granules frequently arranged in longitudinal masses like glands. The whole structure 
appears to unite in providing for the lymphatic and circulatory functions. Certain parts 
of the narrow anterior region of the alimentary canal also present a somewhat reticulated 
appearance, probably from the arrangement of the glands in the wall. 
From the dorsal region of the buccal chamber the proboscidian sheath, a tube 
externally somewhat resembling the former, proceeds backward to be attached to the 
alimentary canal about its anterior third. This tube did not appear to have any 
communication with the canal, but the tissues were so soft that the slightest inter- 
ference caused rupture, and thus several points escaped notice. Externally this 
tube is of a dark madder-brown colour, and curiously ridged longitudinally, the free 
edges of the ridges being fimbriated. So far as could be made out in the softened 
specimen, the apparatus terminated posteriorly by becoming attached to the wall of the 
alimentary canal, after a course of about an inch and a half, the terminal ridge being- 
provided with a number of long fimbriae (PL XXXVIa. fig. 7). Internally are two slender 
white processes, which probably represent the proboscis. In section the external sheath 
presents a hyaline layer, apparently structureless, though generally marked by transverse 
wrinkles. Immediately within is a thick stratum of rounded cells and granules, bounded 
internally by another hyaline coat similar to the former. The rounded cells are slightly 
coherent, and contain brownish pigment. The central area is occupied by masses of 
granules and sections of the slender whitish tubes. The latter have a firm external 
layer and a granular central region. 
The minute structure of the oesophagus differs quite from the foregoing. Externally 
is a coat composed chiefly of longitudinal fibres, followed by a firm circular muscular layer, 
which adjoins the lining of cylindrical epithelium. The latter consists of long fibre-like 
granular cells defined internally by a granular limiting membrane. This region of the 
canal also possesses the mesenteric vessels with the large refractive bodies in their walls. 
The whole alimentary canal was filled with a whitish pulp consisting of a vast variety 
of Diatoms and their debris and a considerable number of Foraminifera, chiefly 
GlohigerincB. The great length of the alimentary canal is peculiar, and cannot altogether 
be associated with a diet mainly composed of vegetable organisms (Diatoms), for the 
system is no longer in the phytivorous than in the carnivorous Eunicidse and Nereidse. 
Below the oesophageal region anteriorly is a series of transverse glandular processes, 
three or four in number and symmetrically arranged, which probably represent the 
reproductive organs. The upper surface of these organs is papillose, and they are 
fzOOL. CHALL. EXP. PART XXXIV. 1885.) LI Vi 
