DESCRIPTION OF PLATES. 145 
induced most modern authorities, including Mr. 
Carter, to deny to the representatives of Euglena 
and its allies the rank of animal organisms, they 
referring them rather to the division of the Proto- 
phyta, or lower unicellular plants. The present 
author’s views, to within a comparatively recent 
date, harmonized with this decision; but a still 
later and more exhaustive examination of the 
typeform of the genus £. viridis, made in April, 
1877, has resulted in an entirely opposite opinion. 
Keeping animalcules of this species for a_pro- 
longed interval in water, with finely pulverized 
carmine, and submitting them to a magnification 
of eight hundred diameters and upwards, the pas- 
sage into their bodies, at the anterior extremity, 
of exceedingly fine particles of this pigment was 
repeatedly observed, as also the accumulation, 
in various parts of the body-substance, of small 
globular aggregations of the particles ingested. 
Hitherto, this anterior region of Euglena has been 
represented as exhibiting a bilabiate aspect, and 
the flagellum as a thread-like extension of the 
upper of the two lip-like prominences. With the 
aid, however, of the high magnifying power em- 
ployed on this occasion, it was clearly shown that 
the inner surfaces of these lip-like prominences 
actually represented the upper and lower boun- 
dary-walls of a conical or infundibular excava- 
tion or vestibule, the innermost recess of which 
fulfils the office of an oral aperture by permit- 
ting the free passage of exceedingly minute food- 
particles.” 
10 
