12 
and the observation of fresh species is required, and Dr. Greef s researches 
have therefore great value. While considering the subject matier of Dr. 
Greef's paper, it may be well to keep in mind the present state of opinion in 
England respecting the absence of all organization in that class of Protozoa 
which includes the Rhizopods and Amoebse. For this purpose I give here 
an extract from Huxley's Lectures, published in 1864. In his elements of 
comparative anatomy, the Author thus introduces the Rhizopod : — j 
"It seems difficult to imagine a state of organization lower than that of 
Gregarinida, and yet many of the Rhizopods are still simpler. Nor is there 
any group of the animal kingdom which more admirably illustrates a very 
well founded doctrine, and one which was often advocated by Hunter him- 
self, that life is the cause and not the consequence of organization. For in 
these lowest forms of animal life there is absolutely nothing worthy the 
name of organization to be discovered by the microscopist, though assisted 
by the beautiful instruments now constructed. In the substance of these 
creatures nothing is to be discovered but a mass of jelly, which might be 
represented by a little particle of thin glue, — not that it corresponds with the 
latter in composition, but it has that texture (?) and sort of aspect. It is 
structureless and organless., and without definitely formed parts ; nevertheless 
it possesses all the essential properties and characters of vitality. It is pro- 
duced from a body like itself; it is capable of assimilating nourishment and 
of exerting movements. Nay, more, it can produce a shell, — a structure, in 
many cases, of extraordinary complexity and singular beauty." 
"That this particle of jelly is capable of combining physical forces in such a 
manner as to give rise to these exquisite and almost mathematically arranged 
structures — being itself structureless, and without permanent distinction or 
separation of parts — is, to my mind, a fact of the profoundest significance." 
(p;>. 10, 11.) 
In a later chapter (p. 83) Huxley returns to the discussion of the limits 
and subdivisions of the class Rhizopoda, and briefly states the following as 
the conclusions to which a careful study of the extant literature of the subject, 
as we'll as his own investigations, lead. 
It appears that three, or perhaps four, types of structure obtain among the 
Rhizopoda. 
1st. That of the Amoebag, Rhizopods with usually short pseudopodia, a 
nucleus, and a contractile vesicle. 
2nd. That of the Foraminifera-Rhizopods, devoid of nuclei and of con- 
tractile vesicle, and for the most part with long pseudopodia, which commonly 
run into one another and become reticulated. 
3rd. That of the Th&lassicollas, provided with structureless cysts, 
