402 Prof. H. James-Clark on the Anatomy and 
of a cell that it should possess a tangible, distinctly differentiated 
envelope. 
At the present day we may safely consider every one of the 
minutest centres of organic development and action as so many 
individual cells (not only potentially, but as essentially so as are 
any of the most decidedly wall-bound cells of the highest kind 
of tissue), and yet not become liable to the accusation of leaning 
toward a visionary method of investigating or interpreting the 
phenomena of nature. It really seems as if the much-abused 
spirit of Oken were about to have its revenge, and the prophetic 
vision of that immortal genius were soon to be realized by the eyes 
of the philosophers of the present day. Happily, among the 
rising generation of the naturalists of this country, a growing 
independence of thought and action—too long under the shade 
of the upas tree of fictitious authority, and allured by the 
deceitful and fascinating exterior of superficial, glittering, swift, 
and hasty generalization—is leading to this result with rapid 
strides. 
Neither the genius of a Spencer nor the incomparable inge- 
nuity and tact of a Tolles are able to increase the availability of 
the microscope as rapidly as the requirements of scientific pro- 
gress demand; and if one would see beyond the mere optical 
image of the instrument, he should, by careful and judicious 
treatment, train the eye to develope to the requirements of the 
occasion. It must become to him a sliding-scale of adjustable 
optical powers. The tutored eye of Ehrenberg saw far more 
than the microscopes of his earlier days could help him to dis- 
cern. The truth of this is especially observable in the surpass- 
ing naturalness and life-like character of his illustrations, so 
often superior to the delineations of his more modern compeers. 
When we have combined the effect of the former with the more 
accurate details of the latter, we shall then, and not till then, have 
arrived at an honest representation of animal life, and have laid 
a firm foundation for a series of deductions and generalizations 
whose influence shall be felt beyond the brief flitting period in 
which they were produced. 
That investigation which, although confined within a narrow 
circle, is the most thorough, and at the same time truthfully 
recorded, is far more valuable for the future than a course of 
observations which extends over a larger field and is carried out 
on a grander scale, but lacks the element of completeness. A 
thorough and elaborate study of one single species will carry 
the possessor of such knowledge immeasurably deeper into the 
secrets of life, and inconceivably further along the road of pro- 
gress, than a superficial, lightly tripping survey of the whole 
kingdom of animals. In the former case, for each newly dis- 
