100 THe Microscope. 
Pith—Thin-walled, brownish, hexagonal cells of paren- 
chyma make up the pith. Occasionally, pitted marks are 
found on the surface of the cells. 
DESCRIPTION OF FIGURES.—Fig. A.—a and a’, cork; b and b’, the green layer 
of the bark; ¢, liber fibre; h, stone-cells; d, cambium; e, medullary rays; m, pitted 
cells; f. wood prosenchyma; i, parenchyma, or liber layer of the bark. Drawn with 
a 4-10 inch objective, and an “A” eye-piece. 
Fig. B.—h, stone-cells; ¢, 1, cross-section of liber fibre, ¢, 2, longitudinal view 
of the same; m, pitted cell of the wood, longitudinal section. Drawn with a cam- 
era lucida, with an 44 inch objective, and an ‘‘A”’ eye-piece. [Fig. A and B reduced 
one-third.] 
—__—~e»>—___—_ 
ASTASIA versus ENGLENA. 
J. M. ADAMS. 
| ENT, Stein and others have made quite a change in the classi 
fication of Astasia and Englena, retaining the old features 
of the pigmentary eye spot and caudal extremity of Emglena, but 
adding greater distinctions in the oral aperture and endoplasm. 
The Astasia has a large widely dilatable clearly defined oral 
aperture leading into a distinct tubular pharynx or cesophagus, 
capable of taking in quite large particles of food or colored 
granules which may temporarily give coloring to the internal 
portion as appears to the naked eye, but not really, coloring the 
otherwise always colorless and homogeneous endoplasm. 
The Englena has no distinct oral aperture, or at best an ex- 
tremely small and almost invisible oral aperture, not dilatable 
nor continuous and able to take in only the minutest food par- 
ticles, while the endoplasm is capable of assimilating chloro- 
