ETTSPIO GEAVJEBI. 179 



Reproduction. — The specimen is a female with small ova. 



This form differs from the Sp. filicornis, 0. Fabricius, as indicated by (Ersted, 1 in its 

 size (8 lines and -J a line broad), in the two pairs of eyes ((Erstecl's being wide in front) in 

 not having the four black points on the last segment (singnli segmenti margine posteriore 

 punctns 4 nigris notato), and in the disappearance of the branchiae about the middle of 

 the body. Though having four anal cirri, like Pygospio it differs in the arrangement of 

 the branchiae, which, in the species mentioned, commence on the thirteenth segment. 



Montagu's 2 (1808) Spio crenaticornis is somewhat like Polyclora without the large 

 bristles in the fifth series, and posteriorly it has two broad, short cirri. It may be allied 

 to Pygospio, for minute details in the figures are uncertain. Montagu termed it crenati- 

 cornis from its crenate tentacles. It had a bifid snout and four eyes. The branchiae 

 occur from the anterior to the posterior end. Its tubes were attached to Sertularians. 



2. Eltspio GRAViERi, 3 n.s. Plate XCVIII, figs. 5 and 5 c— head and tail; Plate 0, figs. 4 

 and 4a — fifth and tenth feet; Plate CV, figs. 8 and 8 b — bristles and hook. 



Specific Characters.— Head produced anteriorly into a rostrum with two small frontal 

 tentacles, the central region supported by the buccal segment on each side. Median 

 ridge goes backward to the first segment. Tentacles absent in the example. Body about 

 an inch in length, little tapered anteriorly, gradually diminished posteriorly, and ending in 

 two subulate caudal cirri. Branchiae commence on the first segment and continue 

 apparently to the posterior end. Foot with a narrow and prominent superior lamella in 

 front, and a small conical lower lamella. The former becomes small posteriorly, and the 

 latter flattens out as a narrow rim. The bristles show a long dorsal group, a shorter 

 lower group in the superior division, and a similar short group in the ventral division 

 anteriorly, but at the eighth bristled segment the place of the bristles is taken by winged 

 hooks, the main fang of which comes off at a large angle from the neck, and is not very 

 acutely pointed, the rounded crown bearing a single spike. 4 



Habitat. — Found in a tunnel, probably of Dodecaceria or other boring annelid in the 

 spreading form of Lithothamnion between tide-marks, St. Peter Port, Guernsey. So far 

 as could be observed no projecting processes or tubes were appended to the tunnel. 



The head (Plate XCVIII, fig. 5 — 5 a) of this species terminates anteriorly in a 

 rostrum with two short frontal tentacles, and apparently is supported laterally, as in the 

 former species, by a process of the buccal segment. A median ridge continues backward 

 to the first segment, or a little further. The body is about an inch in length, very little 

 diminished anteriorly, and in the softened example seems to taper very gradually 

 posteriorly, but the specimen is incomplete. The branchiae apparently commence on the 

 first foot and continue to the end of the example. They seem to be conspicuous about 

 the middle of the body. 



1 c Arch. f. Naturges/ Bd. x, p. 106, 1844. 

 3 MS. vol., 4to, Linn. Soc, pi. xlix, fig. 1. 



3 Named in honour of M. Charles Gravier, of Paris, who has done so much excellent work in the 

 group. 



4 This, as usual, refers to the lateral view. 



