245 
RECENT RESEARCHES IN MINUTE LIFE. 
By HENRY J. SLACK, F.G.S., Sec. R.M.S. 
[PLATES CXXIII. and CXXIV.] 
O BSERVERS have not yet arrived at sufficient knowledge of 
a great number of the minute organisms known as infu- 
soria to classify them in a satisfactory way. This is especially 
true of the Monadina, or monads, under which name many 
heterogeneous creatures were placed by Ehrenberg and Dujar- 
din. Recently Haeckel has proposed to group together, under 
the name Monera, those lowest organisms which, at their highest 
state of development, are composed of sarcode in a simple 
structureless state. These Monera he places in the lowest rank 
of Protista, a kingdom intermediate between animals and 
plants, which 65 reproduce themselves by monogony and not in a 
sexual manner.” * Amongst the Protista are the so-called 
Moners, Flagellates like Euglena, &c., Labyrinthula, Diatoms, 
Fungi, Amoebse, Rhizopods, &c. It certainly cannot be affirmed 
of all these organisms that they reproduce by monogony to the 
exclusion of a true sexual process, and as the life-history of only 
-a few have been fairly made out, many supposed different species 
may prove to be only various forms of the same creature. It is, 
moreover, somewhat begging the question to say of any small 
living object that it possesses no organisation because we cannot 
perceive it. The minuter forms are in many cases so small that 
it is difficult to see them as wholes with the highest objectives, 
and many probably escape vision altogether. When the whole is 
scarcely visible with the best appliances, it is mere dogmatism to 
say that it has no differentiated parts. The lovvest kind of orga- 
nization may differ little from the molecular arrangements which 
give the crystals of many substances different optical properties 
in different directions, and may continue to elude any means of 
investigation we possess. How low down in the scale of being 
true sexual processes occur is still a matter of speculation.. 
* “ Mic. Die.” 3rd edition. 
