REPORT OjST THE FORAMINIFERA. 
45 
But few years had elapsed before a fresh method of classification was suggested 
by Dr. G. C. Wallich , 1 which is of considerable interest, as being founded upon 
a totally different set of characters. The nature of the pseudopodial extensions of 
the sarcode is regarded by Dr. Wallich as a matter of secondary importance, and 
the features selected for the primary division of the Class into Orders are the 
presence or absence of nuclei and contractile vesicles ; whilst the chemical com- 
position and minute structure of the skeleton, and the form of the pseudopodia are 
only recognised in the subsequent division into minor groups, as shown in the annexed 
table : — 
Wallich, 1865. 
Class. Orders. 
Foraminifera. 
Polycystina. 
Plagiacantliidce. 
A canthometrina. 
Thalassicollina. 
Dictyochidce. 
Actinopliryna. 
Amcebina. 
It would occupy too much space, and without adequate advantage, to follow minutely 
the progress of research, or even to summarise the views of the various authors who have 
written upon the systematic arrangement of the Rhizopoda during the last twenty years ; 
the works of Ehrenberg, Max Schultze, Haeckel, F. E. Schulze, Archer, Biitschli, and 
others will occur to everyone conversant with the literature of the subject, and may be 
consulted by those interested in its history. The scope of the present Report is limited 
to a single section out of the many into which the Rhizopoda are now divided, and the 
more practically useful plan appears to be to introduce in full one of the more recently 
proposed schemes of Classification, in order to represent in its principal features the 
condition of our knowledge at the present time. None perhaps is better suited to this 
purpose than the synopsis appended to Prof. R. Hertwig’s admirable treatise on the 
Radiolaria , 2 of which the following is a translation. 
1 Quart. Journ. Micr. Sci., vol. xiii. p. 82. 
2 Der Organismus der Radiolarien, p. 142. 
(ZOOL. CHALL. EXP. PART XXII. 1884.) Y 7 
RHIZOPODA, . 
I. Herpnemata, with, no definite nucleus and no 
contractile vesicle. 
Skeleton never siliceous, . 
Skeleton invariably siliceous, 
II. Protoderjiata, with definite nucleus hut with 
no contractile vesicle. 
Skeleton solid, 
Skeleton tubular, 
III. Proteina, with definite nucleus and contractile 
vesicle. 
Pseudopodia monomorphous, 
Pseudopodia polymorphous, 
