164 APHRODITA. 
§ 1. Apnroprra crrrosA.—Plate XXIV. Figs. 1, 2. 
Length three inches ; breadth halfan inch. Form linear, nearly of 
equal breadth, throughout flattened, covered by thirteen pair of scales, 
arranged in two rows, nearly parallel, and spreading over the sides, as 
well as over the head. The whole upper surface presents a gelatinous 
appearance, especially when under water. Two stout setaceous antenne 
issue from the head, besides which, there are six bristles with an enlarge- 
ment towards the extremity. At the root of each of the two antennze 
are seated two black eyes. The sides of the body are bordered by forty- 
four or forty-five pencils issuing from nipples, with an external red spot 
at the roots, and denoting division into as many segments. The head is 
red ; the colour of the upper surface faint purple, the under surface of 
fine pearly, somewhat iridescent aspect, traversed by a vivid red line. 
The true colour of the animal is perhaps reddish. The late accomplished 
artist, Mr Peter Syme, acquainted me, that in executing drawings from 
the living specimen represented here, he found some difficulty in fixing 
the precise hue. 
When the scales are detached, each irregularly circular, is about 
three-eighths of an inch in diameter, with an aperture rather of a spheri- 
cal triangular form towards one side. They seem vascular or susceptible 
of distension, and when detached, each resembles a flat drop of pale grey 
or purplish jelly. It is from the peculiar nature of the whole that the 
upper surface seems gelatinous. 
The motion of the animal is very swift, half running, half swimming. 
But it likewise swims rapidly through the water, and with much more 
facility than any other of its tribe. 
Probably the Aphrodita cirrosa preys on living animals, nor does it 
spare even its own species. Of two specimens procured at the same time, 
the one was large and fine, two inches and a half in length ; the other 
not quite half as long, but proportionally broader. After living peace- 
ably together during two or three days, I was surprised to find the former 
attempting to devour its companion. One-half was absorbed into its 
