13 
propulsion of a tolerably sized rowing, boat — yet there is a 
very considerable amount of muscular work in maintaining 
the paddle in position, in the movements of the body, &c. 
Now the increase of temperature amounted to 1°*1 F., a 
much larger quantity than any noticed either during row- 
ing or mountain climbing, where the external work is 
larger. Nor was the decrease which followed the first in- 
crease in the latter cases, noticeable while canoeing, probably 
because the external work was not continued long enough 
to make any great demand upon the internal heat. 
MICEOSCOPICAL AND NATUEAL HISTOEY SECTION. 
October 11th, 1875. 
Joseph Baxendell, F.R.A.S., in the Chair. 
Mr. Plant exhibited specimens of Locusta migratoria, 
found in Ordsall Lane and Peel Park, Salford, after the 
unusually strong equinoctial gales of the end of September. 
“ On the Plybrid British Heath, Erica Watsoni, Benth.,” 
by Charles Bailey, Esq. 
Some weeks ago Mr. E. W. Nix, M.A., when in Cornwall 
with his brother Mr. Arthur Nix, collected, on a wet, boggy 
moor in the neighbourhood of Truro, a heath, whose habit 
and characters struck him as being different both from 
Erica Tetralix and E. ciUaris, and both gentlemen were 
satisfied it was a hybrid form. A small specimen which 
Mr. Edward Nix brought home with him to Manchester 
was shown to me for identification, and I had no doubt in 
naming it as the Erica tetralici-ciliaris of Syme {=E. Wat- 
soni of Bentbam). 
