TIIE INDIAN UMBRELLA. 
309 
Several species of the Aplysia inhabit the waters of the Florida Reef. The ornamentation 
is variable. The specimens were about the size of a large cowrey. 
The shell is never visible, being either very small and covered by the mantle, or wholly 
wanting, and in some instances being translucent and flexible as horn. The common Sea 
Hare (. Aplysia depilans) is a well-known example of this curious genus, which has given its 
name to the entire family. 
The Sea Hares possess the power of throwing out at will a rather large amount of 
a peculiar colored fluid, mostly of a deep violet, which is secreted by part of the mantle. 
This habit formerly caused the Sea Hare to be held in great dread, the popular opinion 
attributing to the violet fluid the most virulent properties, such as staining the skin indelb 
SEA HARE. —Aplysia depilans. 
bly with the purple dye, injuring its texture like strong caustic, and causing the hair 
to fall off. In allusion to the last-mentioned idea, the animal has received its spe- 
cific title of depilans. The illustration is remarkably true to nature, the figure being of 
natural size. 
We will now briefly examine a few of the more remarkable species. 
An oddly-shaped creature, looking as if it were made of some rough membrane covered 
with little projections, is the Dolabella, or Hatchet-shell, so called on account of the form 
assumed by the shell, which is, however, so entirely hidden under the softer parts that it is 
not visible until the lobes have been put aside. 
When separated from the animal, the shell appears small in proportion to the size of the 
creature which formed it, and as it is attached only to the hinder part of the body, it is of 
little use in protecting the soft parts from injury. In color the shell is pure, shining white, 
and pearly ; its substance is very thick, and it is covered with a tough membrane, technically 
called the epidermis. The color of the animal is dull olive-green. 
Our last example of this family is the Lobiger. While swimming, it uses the side lobes 
as fins. This creature is also called Lobe-bearer, in consequence of the rounded and flattened 
lobes that project from each side of the body, much like the four wings of a butterfly. The 
tentacles are also flattened and rather oval, and the eyes are very small and set on the sides of 
the head without any footstalks. The foot is small, and the hinder part of the body is length- 
ened and pointed so as to resemble a tail. The shell is small, oval, transparent, flexible, and 
set on the body so as to act as a shield to the plume-like gills. This species is found on the 
coasts of Sicily. 
There is a curious animal belonging to the next family of mollusks, called, from the mode 
in which the shell is carried, the Imdiam Umbrella. In this creature the body is large, 
roundish, and covered with tubercles, and in shape something resembling a great limpet ; 
