190 
THE VOYAGE OF H.M.S. CHALLENGER. 
species range themselves under five genera. One of the most interesting discoveries in 
Prof. Grube’s series is the occurrence of very large eyes, with lenses in the ventral pair, 
in Odontosyllis hyalina from the Philippines and Singapore. The ocular region in this 
species is so unusually large as to simulate the condition in the Alciopidse. Eleven 
Syllidians are given in the same author’s Annulata CErstediana, chiefly from St. Croix, 
one of the Windward Islands ; while only one species from West Africa was procured 
by the “ Gazelle.” A single new example also is described by Alarenzeller from Southern 
Japan, but having the peculiarity of a “wing” at the tip of the bidentate terminal 
pieces of the bristles. Twelve species are mentioned by Schmarda, but his descriptions 
are somewhat indefinite. 
In the present collection none occur beyond 600 fathoms, but in the “Porcupine” 
Ehlers^ describes a form {Syllis abyssicola) from a depth of 1380 fathoms, and another 
from 1443 fathoms. They range to the littoral region; and especially abound in the 
waters of the Mediterranean, and those of Madeira, where they formed the subject of 
careful examination recently by Langerhans.^ 
Eusyllis, Malmgren. 
Eusyllis tubifex, Gosse. 
Efabitat. — Dredged near Station 48 (off Le Havre Bank, Nova Scotia), May 8, 1873 ; 
lat. 43° 4' N., long. 64° 5' W.; depth, 51 fathoms; surface temperature, 38°'0 ; sea- 
bottom, rock. 
The specimens are about the same size as the British examples, measuring 11 mm. in 
length and 1’5 mm. in breadth. 
The body presents a slight narrowing from the anterior third backward, and is 
rounded dorsally, flattened ventrally. 
The head shows four distinct eyes of considerable size, arranged along the limbs of 
a V. The tentacle rises from the central line, in a plane drawn between the two 
anterior eyes. The antennae are somewhat shorter, but of similar shape, and spring 
from the anterior border in front of and slightly to the inner side of the anterior eyes. 
The palpi are distinct, and separated by a considerable interval. The tentacular cirri 
have a long dorsal and a shorter ventral division. 
A few of the anterior dorsal cirri are long, the first exceeding even the dorsal division 
of the tentacular cirrus. They rapidly diminish, however, so that throughout the rest of 
the body they are of moderate length and slightly fusiform, narrowed at the base, 
dilating and then tapering to a blunt tip. The short setigerous division forms a 
^ Ann. and Mag. Nat. Hist., ser. 4, vol. xiii. p. 295, 1874. 
^ Zeitschr. f. wiss. Zool., Bd. xxxii. pp. 513-591, Taf. xxxi.-xxxiii., 1879. 
