366 FORMS OF LEPRALIA, 
beautifully exhibited, some shut up closely in their homes, some just putting forth their heads 
from the cells, others half protruded, and a few with the plumy tufts displayed in all their 
beauty. It is. as well to view this and other polyzoa with different kinds of illumination, both 
as opaque and transparent bodies ; artificial light is, however, to be avoided. 
An allied species is called Lepralia landsborovii. In the Lepralia, as well as the Mem- 
branipora, the process of development is very interesting, especially as it can be readily 
watched under the microscope. 
Towards the end of May, specimens of Lepralia, Flustra, and Membranipora should be 
procured and placed in shallow glass vessels containing sea-water. After a little time, 
minute beings, much resembling the ordinary infusoria, are seen swimming about. Presently, 
the ‘‘gemmules,”’ as these creatures are technically named, become stationary, affix themselves 
to some definite spot, and develop a feather-covered polype, being now similar in shape to 
a single cell of the species from 
which it was produced. Buds, 
or projections, are soon formed 
at the sides, which are rapidly 
developed into new cells, and 
in their turn are the means of 
putting forth new cells. Thus 
it will be seen that each poly- 
zoary spreads from a centre ; 
and that, although a free gem- 
mule is capable of producing 
stationary cells, the greater 
number of cells have never 
passed through the state of 
their original progenitor. When 
a polyzoary has attained a con- 
siderable size, it is not unfre- 
quent to find the margins of the 
group filled with vigorous and 
lively polypes, being those last 
produced, while the centre is 
composed of empty cells, the 
original inhabitants having 
died out from old age. 
The Lepralia spinifera 
differs through the short sharp 
thorns with which the edges of 
the cell are guarded, and the 
curious ovicell, notable for its beautiful sculpturing of ridges radiating around a centre. The 
Lepralia trispinosa is distinguished by three long spines from which it derives its name. 





































































NET-PORED ANIMAL.—Retepora eellulosa. 
A LARGE and interesting genus with about forty or fifty known species, comprises the 
species of Lepralia, Eschara, Lunulites, Cupularia, and Selenaria. Among these especial atten- 
tion must be drawn to Lepralia monoceros, or the Unicorn Lepralia, so called on account 
of the single horn, or club, with which it is furnished ; the Zepralia alata, or Winged Lepralia, 
remarkable for the classically elegant sculpturing and the projecting ‘‘wings;’’ and the 
Lepratia variolosa, so called on account of the peculiar mottlings which are thought to bear 
a resemblance to the face of a person seamed with small-pox. 
The spoor-like avicularium of the Cellepora fusca is a creature notable for its urn-shaped 
and chalky, stiff cells, arranged either irregularly or in the form of a quincunx, 7. e., like the 
cinque spots on a die, +: It isa native of Bass’s Straits. Two tolerably common species 
are the Hschara foliacea, so called from its superficial resemblance to the scar left by a 
