OBTAINED AT THE ISLE OF FRANCE. 27 
if its size be such as not to admit of its being swallowed, it is again disengaged and 
permitted to escape. 
The back of the rays and of the suckers or cilia is marked with transverse lines, 
pointing out the positions of the places where the greatest motion ensues on the curving 
up of these members. 
Genus ANISOMELUS. 
Os tentaculis simplicibus octo, per paria dispositis, filiformibus, prehensilibus in- 
structum. 
Branchie? simplices, tentaculiformes, pedibus haud multd longiores, in segmentis 
corporis quatuor anterioribus site. 
Testa cylindrica, calcarea, erecta, ad basin in saxis immersa. 
Oxs. Numero et symmetrid tentaculorum, necnon branchiarum simplicitate?, a Terebella 
ceterisque generibus affinibus distinguitur. 
Mouth simple, with numerous elongate tentacula surrounding the oral disc. Superior 
rings of the body presenting ventrally from six to ten small tentacula or cilia, which are, 
probably, the branchie: the remainder each with a spatulate foot, from which project 
four spines capable of slight retraction. 
Forming an erect calcareous tube partially immersed in the coral rock. 
ANISOMELUS LUTEUS. 
Tab. V. Figg. 9—14. 
An. totus pallideé luteus. 
Yellow. Tentacula eight: one pair very short ; another pair long ; and an interme- 
diate pair on either side of moderate length : dilating slightly towards their apices, and 
with transverse folds. Beneath the disc and the roots of the tentacula is a double circle 
of minute black dots, and a contracted part or neck, which stands out from, and is 
capable of being received into, the first ring. The rings of the body are only obvious 
in the undistended state of the animal: the three or four superior have minute arms, re- 
sembling tentacula, proceeding from them; the lower have on each side a somewhat 
spatulate foot, declining slightly, and from its apex project four elongate spines, which 
are capable of a moderate amount of retraction. 
On the coral rocks, Black River, Isle of France. 
This minute species forms for itself a thin calcareous tube, which stands up from 
the surface of the rock, but not a sufficient way to admit of the concealment of the 
whole body of the animal within it: in consequence, the tube is prolonged into the 
E2 
