and Species of Diatoms from the South Pacific. 48 
DESCRIPTION OF PLATE I. 
Fig. 1. Stictodesmis australis, . front view. 
Ae Aa: a a side view. 
4. in valve. 
5. Plagiogramma costatum, front view. 
6. ‘5 i side view. 
7 ss spectabile, side view. 
8. Pe constrictum, side view. 
9: fa Atomus, side view. 
10. Omphalopsis australis, front view. 
11. x - side view. 
12. Amphiteras parvula, . side view. 
18. Amphiprora eximia, . front view. 
14, i lata, front view. 
15. a delicatula, front view. 
16. 3 % side view. 
LT. - 2? superba, . front view. 
18. x: nitida, . front view. 
19. b lineata, . front view. 
20. »  £Clepsydra, front view. 
21. »  2paradoxa, front view. 
22. » undulata, . front view. 
All the figures are x 400 diameters. 
On the question, Is Oxide of Arsenic, long used in a very 
small- quantity, mmjurious to Man? By Jonn Davy, 
M.D., F.R.SS. Lond. & Edin.* 
The facts which led me to propose the above question 
were the following :—In Cumberland, within a stone’s cast 
of the Coast’s Railway, between Whitehaven and Broughton, 
is the little church of the parish of Whitbeck, and also the 
farm-house of Whitbeck-head,—names these derived from 
the small mountain stream which descends from Black 
Comb, and so rapidly as to be an almost white line of 
foam. The hamlet, situated at the foot of the hill, consists 
of the farm-house just mentioned, and of five cottages, each 
occupied by a family dependent for water on the rivulet, 
“the Beck,” their inmates using no other. The same water 
is drunk by the cattle of the farm, and by the poultry, 
fowls, geese, and ducks; and, as regards all, with one excep- 
* Read at the Meeting of the British Association in 1862. 
