590 
INDEX. 
Silums, Dr Traill's description of a species found in Deme- 
rara, ...... 377 
Slate quarries, Carnarvon, described, . . . 233 
Snowdon range of mountains, its geology and statistics de- 
scribed by J. S. Menteath, Esq. 209 — General survey, 
210 — State of cultivation of the Conway Basin, 215 — 
Forest trees, 216— Minerals, 218— Metals, 219— Menai 
Basin, 223 — Want of irrigation, 229 — French whin em- 
ployed as food for horses and cattle, 230 — Carnarvon 
slate, 233 — Amount of tons, their value, and population 
employed, 236 — Veins of copper, 238 — Anglesea, 240 
— Its agricultural produce and live stock, 243 — Coal and 
copper, 247 — Cardigan Bay Basin, 250 — Menai iron- 
bridges, 257 — General summary, 258 — List of grasses 
and other plants, ..... 264? 
Spiders, observations on the habits and food of, by Mr Mark 
Watt, . . . . . .365 
Squalus, organ of hearing in the genus, described by Mr 
Buchanan, 144 — S. canus, 145 — S. borealis, 146 — 
Auditory nerve, . . . . .159 
Structure of the eye of the Sword-fish described by Dr 
Grant, . . . . . .113 
Sturgeon, on the anatomical peculiarities of the, by Dr 
, Craigie, 334 — Alimentary canal, 336 — Pancreatoid, 346 
— Spiral valve of the intestine, 353— Liver and spleen, 
356 — Urinary organs, 357 — Additional observations, . 358 
Sword-fish, on the structure of the eye of the, by Dr Grant, 1 IS 
Sun-fish, description of a new species of, by Dr Traill, . 381 
Traill, Dr, description of a Silurus, known in Demerara by 
the name of Gilbacke, .... 377 
description of a new species of Cephalus, which 
it is proposed to name Cephalus Cocherani, Cochran's 
Sun-fish, . . . . . .381 
4 
