88 
THE VOYAGE OF H.M.S. CHALLENGER. 
botli in regard to the shape and length of the tentacle (the organ being much shorter 
in Aphrodita echidna), the form of the head and the absence of eyes. There is nothing 
in the description of the Aphrodita echidna of M. de Quatrefages to give certainty in 
contrasting it with others, but it agrees with the present form in having the felt in a 
single layer, transfixed by the dark brown spines, and in all probability the forms are 
the same. Nothing further is known of the French specimen than that it was procured 
off South America by A. d’Orbigny. 
Aphrodita intermedia, n, sp. (PI. I. fig. 6 ; PI. VIa. fig. l). 
Dredged at Station 23 a, off Sombrero Island, West Indies; lat. 18° 26' N., long. 
63° 31' 15" W. ; depth, 460 fathoms; Pteropod ooze: also at Station 2a, off Culebra 
Island, West Indies, lat. 18° 38' 30" N., long. 65° 5' 30" W. ; depth, 390 fathoms; 
Pteropod ooze. 
A minute ovoid form, measuring about 5 mm. in length and about half as much in 
breadth. 
The whole dorsum is enveloped in a whitish coating of Foraminiferous mud, which 
obscures all the parts of the animal except a few of the ventral bristles along the anterior 
edge. In the natural condition it is, indeed, difficult to distinguish the anterior from the 
posterior end. The dorsal surface is convex, the ventral flattened. On the latter surface 
the spaces between the feet are occupied by masses of the same granular whitish material, 
which also in some parts projects beyond the tips. The whitish coating over the dorsum 
is composed of minute round spicular bodies, white sand-grains of various shapes, and 
debris. The layer is friable, and has only a few fine hairs in its composition. The 
latter have nearly the delicacy of those of Aphrodita, and pass from the upper division 
of the foot in beautiful pale iridescent tufts. They are so mixed with the little white 
spiked bodies and other debris, that it is difficult to detach them, especially as there are 
traces of m inute serrations at the tip. No dorsal spines are visible in the example, a 
feature probably associated with the presence of the dense coating of the whitish granules. 
The specimen, unfortunately, is much softened, so that a minute description of the 
cephalic region is difficult. It is at once seen, however, that the shape of the head 
corresponds to that in Aphrodita, not Lcetmonice — being pear-shaped with the broad 
region posteriorly. Onl}" the base of the tentacle remains in front. No eyes are visible, 
and no ocular peduncles. The palpi are of moderate length, and furnished with elongate 
papillse, which from their pointed tips resemble spines. 
The ventral bristles occur in groups of three or four, supported by a spine in the 
slender foot. The tip of each passes off from the shaft at a characteristic angle (PL VIa. 
fig. 1). There is a very well-marked spur as in Lcetmonice, above which is a region 
densely joilose almost to the terminal hook, and placed on one side like the setose tip in the 
