PROCEEDINGS OF SOCIETIES. 219 
as how otherwise could he come to the conclusion that Arcella vulgaris 
could be but a sub species or even a species of Difflugia ?” 
What on earth my conclusions regarding the limitation of species 
in these lower forms of animal life have to do with the correctness or 
incorrectness of my published description and figures of the structure 
of the Arcelline test I am at a loss to conceive. The one is a matter 
of opinion ; the other a matter of fact. I am quite ready, however, to 
allow that in my humble opinion our knowledge of the biological re- 
lations of the Protozoa and Protophyta is much more likely to be 
increased by taking into due consideration the causes on which 
divergence is mainly dependent, than by seizing upon every trivial 
variation from an assumed type as evidence of specific distinctness. 
How far it is admissible to say that “a correct description ” of the 
structure of the test of Arcella was given “for the first time) by 
Messrs. Hertwig and Lesser,” and that I merely “spoke of sym- 
metrical reticulation and hexagonal interspaces,” the subjoined extract 
will at once show. I may mention that it is taken from the explana- 
tory references which accompany the plates illustrating my memoir 
‘On the Extent and Causes of Structural Variation among the Dif- 
flugian Rhizopods;’ and that a detailed figure is there furnished of 
the structure as it exists in Arcella. 
“Fig, 87. Front view of D. arcella. Fig. a shows the invariably 
hexagonal pitting or reticulation of D. arcella (Arcella vulgaris). This 
can only be made out, however, in a mounted and crushed test, under 
a high power.” * 
I remain, Sir, your obedient servant, 
G. C. Watuico, M.D., &c. 
PROCEEDINGS OF SOCIETIES. 
Royat Microscorican Society. 
Kine’s Coutuece, March 7, 1877. 
H. C. Sorby, Esq., F.R.S., President, in the chair. 
The minutes of the preceding meeting were read and confirmed. 
A list of donations to the Society since the previous meeting was 
ie by the Secretary, and the thanks of the Society were voted to the 
onors. 
The President had great pleasure in announcing that there was 
every reason to believe that arrangements would be made with Sir 
John Lubbock to deliver the first Quekett lecture to the Society on 
May 2. The subject would in all probability be “The Microscopie 
Characters of Ants in connection with their Habits and Instincts.” 
The Quekett medal, which had recently been struck for the purpose, 
would be presented to Sir John Lubbock at the close of the lecture. 
F eee and Mag. Nat. Hist.’ March 1864. Explanation to plate xvi- 
g- . 
VOL. XVII. R 
