THE VOYAGE OF H.M.S. CHALLENGEE. 
34f> 
is sucli that it would be unsafe to say more. The foregoing forms and the Glycera 
brevicirris of Grube all show certain resemblances. 
Glycera sagittarice, n. sp. (PI. XLII. fig. 8 ; PI. XXIIa. fig. 10). 
Habitat . — Dredged on September 29, 1874, olf Arrou Islands. 
An elongated annelid, tapering much posteriorly, and measuring about 110 mm., with 
a diameter of 5 mm. at the widest part, near the anterior third. 
There is little in the contour of the head and body to discriminate the species. The 
teeth, which are admirably concealed on retraction of the proboscis, have a long slender 
process on one side of the base. 
The feet are formed on a similar plan to those of the British species which so closely 
resembles Glycera tesselata, but in addition to the difference in regard to the branchiae 
(which are present in the Challenger specimen) there are other distinctive features. In 
comparing the tenth foot of the two forms it is found that in the foreign example the 
dorsal cirrus is at a greater distance above the foot, that the two long processes of the 
foot are less bulbous towards the tip, and that the ventral lobe is proportionally broader. 
The tips of the ventral bristles also appear to be larger. A little beyond the thirtieth a 
branchial process springs from the upper and anterior part of the foot, and it continues 
for a considerable distance, being at first short and thick, and then somewdiat elongate. 
There is not much in the structure of either dorsal or ventral bristles to distinguish 
them from the British form, except, as already noted, the somewhat longer terminal piece 
of the ventral. Both the latter and the dorsal show indistinct serrations along the 
margin. The tips of the ventral bristles of this and other Glyceridse seem to be triangular 
in transverse section, that is, they have a keel posteriorly, and two serrated margins in 
front. Moreover, from the formation of the bristle it is difficult to get a good lateral 
view (so as to show the entire side), and in most views the double line indicates the 
nature of the anterior edge. The tips of the upper ventral (PI. XXIIa. fig. 10) are longer 
than those of the inferior series. 
A dark brownish mass in the perivisceral cavity consisted of granules and numerous 
slender hairs (bristles). 
This species closely agrees with Glycera capitata in the structure of the body- 
wall, though the nerve-area is less pointed superiorly, indeed, it forms beneath the 
granular outer layer of the region a smoothly rounded arch with two small but distinct 
neural canals superiorly. The papillae of the proboscis are slightly longer than in 
Glycera capitata. 
In the form of the foot this species resembles Grube’s Glycera saccihranchis} from 
^ Anneliclenfauna d. Philippinen, p. 181, Tab. viii. fig. 10. 
