270 AMPHIGLENA MEDITERRANEA. 
they are generally directed forward, with a slight curvature, whilst the. anterior bristles 
are directed backward. The anterior hooks (Plate CX XIX, fig. 5b) have a similar shape 
to those of Amphicora fabricia, that is, have a curved shaft which tapers inferiorly, a shoulder, 
above which is a somewhat narrower neck surmounted by a strong, sharp main fang coming 
off at less than a right angle to the throat, and with two or three strong teeth above it, the 
crown being on the whole more elevated than in A. fabricea. The neck of the hook is also 
slightly bent backward. The posterior hooks, which, as in Amphicora fabricia, occur in the 
last three bristled segments, differ, as Claparéde observed, from those of the species just 
mentioned in their shorter form (Plate CX XIX, fig. 5c), for the basal region is truncated, 
and the posterior outline short and concave, the conspicuous part of the hook being the long 
anterior face and crown—occupied by a small, sharp main fang and numerous minute teeth 
above it. The anterior outline below the main fang bounds a small bay, the prow bending 
up to circumscribe it. The inferior outline is convex. 
The statocysts in this species belong to the second group of Fauvel,' viz., to the closed 
series, in which the statoliths are formed by concentric layers of secretion in the organ. 
Reproduction.—Marion (1872) describes the reproductive elements in each sex as 
developing in hyaline investments on vascular tufts in each segment. 
Mature specimens were found by Southern in September in Blacksod Bay, Ireland. 
Genus CLXIX.—AMPHIGLENA, Claparede, 1864. 
Eyes on the first (achetous) segment and on the pygidium. Branchie similar to those 
of other Sabellids and more numerous than in Orza; no collar. Dorsal bristles of two kinds 
on the anterior (thoracic) region, viz. those with elongated tips and narrow wings and those 
with short tips and broad wings (spatulate). Anterior hooks avicular, accompanied by 
“flag” bristles ; posterior hooks also avicular. Hermaphrodite. 
1. AMPHIGLENA MEDITERRANEA, Leydig, 1851. Plate CXIIIA, fig. 4 ventral, and CXV, 
fig. 4—dorsal view of body ; Plate CXXXI, figs. 4—4 f—bristles and hooks. 
Specific Characters —Cephalic region with ten to thirteen branchie, each having a 
double row of ciliated barbules about thirty im number, shorter at the base and tip 
than in the middle, the tip ending m a long and slightly tapered process with a narrow 
web at the base. Body about 8 mm. in length, of twenty-nine to thirty-three segments, 
usually little tapered anteriorly, but more so posteriorly, ending in a bluntly conical or 
rounded pygidium which bears four to six pairs of eyes. First achetous segment has 
four eyes. Pair of spherical statocysts in the second segment, and two or three minute 
winged bristles dorsally. The next seven segments have dorsal tufts of bristles. Anterior 
bristles of two kinds, the upper or dorsal series with narrow wings, the lower with spatulate 
tips (from the broad wings), the ends being hair-like. Avicular anterior hooks commence 
on the second bristled segment, and have a long main fang with three or four spikes in 
lateral view above it; posterior outline much curved, and the posterior process long. A 
1 «Comp. Rend. Acad. Se. Paris,’ December 29th, 1902. 
