166 
POPULAR SCIENCE REVIEW. 
The Nervous System. — I liave not been able to find any trace 
of a brain in any of the species of tbe genus. Two eyes are 
discernible in tlie new-born young, and even in tbe embryo 
some time before maturity. I bave also, by using reflected 
light, detected these organs in half-grown individuals, which had 
well-formed and conspicuous cases. In an adult F. cor nut a I 
have seen a single eye by reflected sunlight, and two in un- 
hatched eggs, and in young that had developed the disk. The 
eye in the adult, though now and then it shone out brightly, was 
frequently invisible with any adjustment of forms : — so delicate 
and difficult are often these determinations ! In another of the 
same species I was able to bring- out under pressure one eye, 
minute, but perfectly distinct, but only one. 
Around the neck (in F. ornata and cornuta certainly) goes a 
band of greyish granular substance, which sends off threads 
toward the margin of the disk, and in some specimens may be 
traced running as an evanescent thread around the edge, close 
to the marginal vessel. These may be, and probably are, 
threads of nervous matter. 
The Muscular System closely resembles that of Steplia- 
noceros, but it is much less distinct. The action of muscular 
threads stretching across the clear disk to the knobs and inter- 
mediate points, whereby different parts of the outline are 
twitched inwards, and the whole more or less collapsed, can often 
be seen. 
The Reproductive System and Development. — The organs 
of reproduction, so far as known, agree with those already de- 
scribed. The ovary, a large translucent organ, nearly fills the 
ventral half of the body, and may generally be recognized either 
by its immature eggs, — clear spherules, each with its nucleus, — 
or by a great semi-opaque developing egg, as yet soft and shell- 
less, in the lower part. On being extruded, the eggs, now 
clothed with a hard and brittle shell, of a long-oval form, 
accumulate in the case, sometimes adhering to the foot and 
body of the animal, sometimes to the interior wall of the 
case (plate ix., fig. 1). 
Several hours after being laid, the egg-shell bursts, and the 
infant Floscule makes its appearance. It is a white, cylindrical 
maggot, blunt at the front end, with a central orifice, whence 
protrudes a short brush of cilia ; but the margins are capable of 
unfolding, when the cilia are seen to form a whorl around the 
truncate summit, swiftly rotating (fig. 2) . The margin soon begins 
to bud forth the little knobs, around which the cilia are gathered ; 
these quickly increase in length, and the angular flower-like disk 
gradually forms (fig. 3) . Meanwhile, the little creature, which was 
at first free, attaches itself by its hinder end, and assumes the con- 
ditions as well as the form of the parent. The case, however, 
