JOURNAL OF MICROSCOPICAL SCIENCE. 
DESCRIPTION OF PLATE IV, 
Illustrating Dr. Redfern’s paper on Flustrella hispida. 
Fig. 
1.—Ceenecium of Flustrella hispida removed by horizontal section from 
the frond of Chondrus mamillosus. 
2.—Ditto, ditto, showing cells with fewer hairs on their sides and a more 
imbricated arrangement. 
3.—A single cell of the same separated from those which surrounded it. 
Figs. 1, 2, and 3 magnified. 
3 dis.— Cencecium of a specimen gathered on the coast of North Wales. 
4.—Polypide removed from its cell, showing its digestive viscera. 
5.—Portion of a tentacle, showing the natural state of its investing ciliated 
epithelium. 
6.—Ditto, denuded of its epithelium. 
7.—Ditto, showing its epithelial cells distended by fresh water. Figs. 
5, 6, and 7 magnified. 
8 to 10.—Unciliated ova or statoblasts densely filled with cells. 
9.—Ditto, from which some of the cells have escaped, showing the remain- 
ing contents more distinctly cellular. Figs. 4, 8,9, and 10 magnified. 
11.—A single polypide in its cell, with a gemma forming on its wall. 
12.—The same after two days, showing a striation produced by rows of 
highly refractive corpuscles. 
13.—Ditto, on the third day, showing the polypide like a bud at the bottom 
of the new cell. 
14.—Ditto, on the fourth day, showing traces of the formation of three 
other gemmee. , 
15.—Ditto, on the seventh day. The polypide has assumed the form of a 
bent tube; the cell has four well-marked hairs formed on it; one 
only of the other gemme is now distinctly seen. 
16.—Ditto, on the twelfth day. The projecting part of the cell has become 
flexible and greatly more prominent; the wall of the perigastric 
space and the tentacles are quite distinctly seen; no other gemma 
is distinctly visible. 
17 and 18.—Ditto, on the thirteenth day, showing states of retraction and 
protrusion. The movements are now remarkably distinct, the ten- 
tacles much longer, the perigastric space clearer, the rows of refrac- 
tive globules greatly diminished in number and size. 
19 and 20.—Ditto, on the seventeenth day, showing the whole digestive 
system beautiful ly distinct, as well in the state of retraction as of 
protrusion; a gemma appears to be forming on the side of the 
‘newly developed cell. 
