THE YOUNG SCIENTIST. 
125 
charcoal— to form the substance of their 
delicate translucent tissues, and sending 
forth the oxygen as their contribution to 
the purification of the adjacent water, and 
the renovation of our atmospheric air. 
This was a good sign, for health^^ vegeta- 
tion is favorable to many of the most in- 
teresting forms of infusorial life. Ac- 
cordingly the end of a walking-stick was 
inserted among the green threads, and a 
skein of them drawn up, dank, dripping, 
and clinging together in a pasty-looking 
mass. To hold up a morsel of this mass, 
and tell some one not in the secrets of pond- 
lore that its dripping threads were objects 
of beauty, surpassing human productions, 
in brilliant color and elegant form, would 
provoke laughter, and suggest the notion 
that you were poking fun at them, when 
you poked out your stick with the slimy 
treasure at its end. But let us put the 
green stuff into a bottle, with some water 
from its native haunt, cork it up tight, and 
carry it away for quiet examination under 
the microscope at home. 
Here we are with the apparatus ready. 
We have transferred a few threads of the 
conferva from the bottle to the lire box, 
spreading out the fine fibres with a needle, 
and adding a drop of water. The cover is 
then gently pressed down, and the whole 
placed on the stage of the microscope, to 
be examined with a power of about sixty. 
A light is thrown somewhat obliquely by 
the mirror through the object, the focus 
adjusted, and a beautiful sight rewards 
the pains. Our mass of conferva turns 
out to contain one of the most elegant 
species. Fine hair-like tubes of an or- 
ganic material, as transparent as glass, 
are divided by partitions of the same sub- 
stance into cylindrical cells, tlirough 
which a slender ribbon of emerald green, 
spangled at Intervals with small round 
expansions, is spirally wound. We shall 
call it the Spiral Conferva, its scientific 
name being Spirngyra quinina. Some 
other species, though less elegantly 
adorned, make a pleasing variety in the 
microscopic scene; and appended to some 
of the threads is a group of small crystal 
bells, which jerk up and down upon spi- 
rally twisted stalks. These are the " Bell 
Flower Animalcules " of old observers, 
the Vorticellw, or little Vortex-makers of 
the present day. Other small creatures 
flit about about with lively motions, and 
among them we observe a number of 
green spindles that continually change 
their shape, Avhile an odd-looking thing- 
crawls about, after the manner of certain 
caterpillars, by bringifig his head and tali 
together, shoving himself on a stej), and 
then repeating the process, and making 
another move. He has a kind of snout, 
behind which are two little red eyes, and 
something like a pig-tail sticks out be- 
hind. This is the Common Wheel-bearer, 
Eotifer vulgaris, a favorite object with 
microscopists, old and young, and capa- 
ble, as Ave shall see, of doing something- 
more interesting than taking the crawl we 
have described. 
A higher power, say one or two hundred, 
may be conveniently applied to bring out 
the details of the inhabitants of our live 
box more completely; 1)ut if the glasses 
are good, a linear magnification of sixty 
will show a great deal, with the advantage 
of a large field, and less trouble in follow- 
the moving objects of our search. 
Having commenced our microscopic 
proceedings by obtaining some Euglente, 
I Vorticellse, and a Eotifer, w^e are in a po- 
' sition to consider the cliief characteristics 
I of three great divisions of infusoria, which 
I will often engage our attention. 
! It is well known that animalcules and 
I other small forms of being may be found 
j in hifi(s'H)}is of hay or other vegetable 
I matter, and hence all such and similar 
I objects were called Infusoria by early ol)- 
I servers. Many groups have been separ- 
I ated from the general mass compre- 
I hended under this term, and it is novi 
\ used in various senses. Tlie a.utliors of 
the " Micrograplnc Dictionary" employ 
it to designate "a class of microscopic 
j animals not furnislied with either vessels 
j or nerves, but exliibiting internal spheri- 
cal cavities, motion effected by means of 
cilia, or variable i)rocesses formed of tlie 
substance of the l^ody, true legs being ab- 
sent." The objection totliis definition is, 
that it to some extent represents theories 
which may not be true. That nerves are 
absent all through the class is an assump- 
tion founded merely upon the negative 
