KEPORT ON THE ANNELIDA. 
161 
' occurrence of Nematoids in such positions is by no means common. The ventral cirrus 
is large and lanceolate, and at the base of the ventral lamella sujDeriorly is a short 
conical cirrus. 
The short anterior bristles (PI. XI Va. fig. 9) are boldly barred transversely. They 
are straight and regularly tapered, but present comparatively few points of decisive 
i specific distinction. The longer forms (PI. XI Va. fig. 10) are slender, gently curved, 
and have the convex edge covered with minute spikes. Some of the examples from 
Kerguelen present posteriorly stouter and darker long bristles (PL XIVa. fig. 11), with a 
shghtly different curve. The serrated region is decidedly shorter, while the shaft is 
longer. 
Besides the parasitic Nematoids, the branchiae are the seat of many Loxosomce, while 
the long bristles abound with a short thecate Infusorian as in the British and other 
forms. 
The muscular rugose alimentary canal of the larger specimens was emj)ty, but in 
others mud, rich in sponge-spicules, Radiolarians, Diatoms, and the bristles of Annelids 
(Spionidse) occurred. 
In the structure of the body-wall this species in the main agrees with Nejohthys ccBca, 
Fabr., though the dorsal longitudinal muscles are less bulky inferiorly, in transverse 
section. The ventral longitudinal are also less massive. The ventral area is proportion- 
ally larger, and the combined oblique and vertical muscles do not form so complete an 
arch as in Nephthys cceca. The hypoderm, as in the latter, seems to be wholly external. 
The nerve-trunks are large, and each has an internal {i.e., near the median line) neural 
canal of considerable size. In some sections smaller canals appear above the former, but 
such may be due to imperfect preservation. 
The proboscis seems to agree with typical forms — having its cnticular and hypo- 
dermic layers internally, and its radiate fibres externally — much after the plan of that 
in the Polynoidse, only there are no distinct folds at the poles. The horny teeth are 
cuticular. 
Professor Grube’s examples were procured at Kerguelen by the German exploring ship 
“Gazelle.” A specimen in the British Museum, also from Kerguelen (75, 7, 15, 4), is 
labelled (by Grube in 1876) simply Nephthys. It had not been forwarded previously for 
examination with the other Annelids from the same region. 
Nephthys dibranchis, Grube (PI. XXVI. figs. 8, 9 ; PL XXVII. fig. 5). 
Nephthys dibranchis, Grube, op. cit. (S.M.S. “Gazelle”), p. 536, 1867. 
Habitat. — Dredged in the Arafura Sea, south of New Guinea. Professor Grube’s 
specimen came from the same region. 
(ZOOL. CHALL. EXP. — PART XXXIV.- — 1885.) 
LI 21 
