MEETINGS OF SOCIETIES. 143 
force of gravity had not acted? The first law of motion says 128 
feet. The force of gravity, however, does act. How high, then, 
does the mass rise? 112 teet. What, then, was the “ work” of 
the force of gravity? It stopped the mass from rising the 16 
feet additional ; it would have risen if gravity had not acted. This 
then is all the work the force of gravity does in the jst second, 
and not 112 foot pounds as the text-books assert it does in 
negative work.—I am, &c., 
T. WAKELIN, B.A. 
Greytown, March 31, 1882. 
NEW ZEALAND FERNS. 
(To the Editor N.Z. JOURNAL OF SCIENCE.) 
Sir,—In my work on ‘‘ Ferns and Fern Allies of New Zea-. 
land,’ I have unaccountably fallen into the error (at p. 31) of 
making Mr. Kirk state that Dicksonia fibvosa, Colenso, is a variety 
of D. squavvosa, Swartz, and I quote his remark on the subject 
(N. Z. Inst. Trans., vol. X., app. p. 43). A reference to Mr. Kirk’s 
paper will show that he places it under D. antarctica, Lab. I do 
not know how I can have made such a slip. I have to apologise 
to Mr. Kirk tor the mis-statement.—I am, &c., 
Geo. M. THomson. 
MEE CLINGS OF SOCIETIES. 
—_ <+—_— 
eeaGcO INSTITUTE AND DUNEDIN NATURALISTS’ 
: PLD CrhUB, 
28th March.—The session was opened by a conversational 
meeting, at which numerous interesting exhibits were shown. 
Geo, M. Thomson, Esq., Vice-President, was in the chair. 
New Members.—Messrs. Robt. Jones, James Henry, and 
Wm. A. Dickson. 
Besides a considerable number of microscopes,. including 
several dissecting instruments, the following objects were ex- 
hibited, amongst others :— 
(1) A fine collection, most beautifully preserved, of marine 
Invertebrates, prepared at the Zoological Station, Naples. 
(2) A large and valuable collection of Foraminifera, received 
from Prof. W. K. Parker, F.R.S., Royal College of Surgeons, 
London. 
(3) Casts of Plesiosaurus, Ichthyosaurus, Pterodactyl, 
Iguanodon, Labyrinthodon, Machairodus, Hipparion, and Engis 
and Neanderthal skulls; together with a number of new speci- 
mens from the Otago Museum. All the above were shown by 
Prof. Parker. 
