ARCHERINA. 1138 
apparently represents the nucleus. Occurring singly 
and in tetraschistic colonies. The chlorophyl cor- 
puscle, which takes the place of a true nucleus, is 
unique, and sufficiently characteristic of this genus. 
1. Archerina Boltoni Ray Lankester. 
(Plate XIV, figs. 2-6.) 
Archerina Boltont Ray Lanxestrer in Q. J. Micr. Sci. XXV, 
n.g. (1885), p. 61, t. vii, and in Encycl. Brit. ed. 9, XTX 
(1885), p. 840, f. 11, 8-11. 
Body of each individual sphere about one-thousandth 
of an inch in diameter, consisting of a sharply-defined 
mass of refringent pr ‘otoplasm from the surface of 
which radiate stiff filaments, some of which are four 
times as long as the diameter of the sphere and taper 
from the base towards the extremity. The base of 
each filament, according to Prof. Lankester (whose 
description we quote), is relatively broad, and appears 
to join, without penetrating, the surface of the sphere. 
No membrane or pellicle can be detected on the surface. 
Within the body is usually one large spherical vacuole ; 
sometimes there are more, varying in size. 
Dimensions: Individual spheres, 1-2000" (Lankester). 
Ponds near Birmingham, Mr. Thomas Bolton (after 
whom the species was named), the generic name being 
established in honour of Mr. William Archer. 
This rhizopod was found in great abundance in 
pond-water, associated with desmids and other minute 
chlorophyl-bearing alge. Its spherical corpuscles” 
may at first, Professor Lankester says, be mistaken for 
those of such microscopic plants, but a little attention 
is sufficient to enable one to detect around many of 
the bright green spheres a halo of radiant protoplasm 
frequently in the form of very long and stiff filaments. 
Once recognized it is not difficult to distinguish 
Archerina, 10 its various phases of growth and multi- 
plication, from its associates. 
8 
