450 DR. BAIRD ON A NEW SPECIES OF ANNELIDE. 
They are all of a brilliant carmine-red colour, which, however, fades much by keeping 
in spirits. The sete on the feet are in two separate tufts. The dorsal tuft (fig. lc) 
issues from a stout peduncle, the edge of which is tinged with the same colour as the 
branchie, to which it is attached. These sete are extremely numerous, of very 
considerable length, of a pure white colour, and are straight, sharp-pointed, and 
slightly serrate on the outer edge (fig. 6). The ventral tuft (fig. 2 b) consists also of very 
numerous white setze, of considerable length, but of a somewhat different structure. 
Each seta is stouter than those of the dorsal tuft, rather blunt and slightly curved at the 
extremity, and is slightly toothed or bluntly serrate near the point, and exhibiting at a 
short distance from the extremity a small projection or tooth (fig. 7). These setze, espe- 
cially those of the dorsal tuft, are so numerous and fine that, along with their pure white 
colour, they resemble tufts of fine cotton-wool. It is difficult, however, to keep them 
from falling off; and the specimens now preserved in spirits do not show half the beauty 
they had when fresh. The cirri (fig. 5 c) are rather slender, and slightly tinged with 
carmine near the free extremity ; they are considerably shorter than the setze, which 
completely envelope them and conceal them from view, unless pulled aside. 
The specimens of this worm now in the British Museum were brought by Mr. Watson 
from the Island of Ascension, where they are collected by the boatmen and sold as curi- 
osities. They pretend that they are of a venomous nature, and are able to inflict serious 
. wounds upon those who incautiously handle them. This idea no doubt takes its origin 
from the numerous setze with which their feet are clothed, but which, though (to judge 
from their appearance, as shown figs. 6 & 7) in reality powerful weapons for offence and 
defence against those animals which prey upon or are fitted for food for these, are in fact 
powerless for harm to human beings. 
A similar-looking and brilliant-coloured species was taken by Bory St. Vincent amongst 
the rocks and lava off the coast of Metana in the Morea; and if is curious that this 
bright-hued species should be taken also on the coast of a volcanic island. 
DESCRIPTION OF THE PLATE. 
PLATE XLV. 
Fig. 1. Amphinome didymobranchiata, dorsal aspect, natural size (in spirits, and rather contracted) : 
a, caruncle; 6, û, b, branchize; c, dorsal tuft of sete. 
° Fig. 2. Ventral aspect of animal, natural size: a, proboscis extruded; 5, ventral tuft of sete. 
Fig. 3, Extremity or fleshy pad of proboscis, slightly enlarged. 
Fig. 4. Caruncle, with five or six anterior segments of body (13-inch power). 
Fig. 5. Branchie, magnified : a, smaller branch; 4, larger branch; c, cirrus. 
Fig. 6. Seta of dorsal tuft (ths power). g 
Fig. 7. Seta of ventral tuft (4 ths power). 
