262 
BATHYMETRICAL SURVEY OF 
far to the north on the flanks of Beinn Dearg (3547 feet). Still further 
on the river Conon is joined by the river Orrin, and finally falls into 
the head of the Cromarty firth at Dingwall. The river Glass, which 
in its course flows through Loch Glass, rises on the flanks of Beinn nan 
Eun, and empties itself in the Cromarty firth at Balconie Point. The 
river Alness, which flows through Loch Morie, rises on the flanks of 
Beinn a’ Chaisteil, and falls into the Cromarty firth at Alness Point. 
The geology of the district is dealt with by Drs. Peach and Horne, 
whose notes are appended, as well as a few biological notes by Mr. James 
Murray. Mr. R. M. Clark, b.sc., who took part in the survey of the 
lochs in the Conon basin in 1902, has supplied us with several series 
of temperatures taken by him the previous summer (1901) in Lochs 
Achilty, Garve, Achanalt, a’ Chuilinn, and a’ Chroisg, which are here 
incorporated."^ 
* These temperattu’e observations, taken by Mr. Clark in the summer of 1901, are 
interesting, as compared with the observations taken in the same lochs in the summer 
of 1902, when viewed in connection with the atmospheric conditions in the two seasons. 
It will be observed that all the readings taken in the superficial waters of these lochs 
in 1901 are higher than those taken in 1902, and this is evidently related to the warmer 
season in the first-named year. Thus the mean temperature over Scotland for July, 
1901, was 61°-8 Fahr., or 3° above the long-period average for that month, while for July, 
1902, it was 54°'4, or 4J° below the average; for August, 1901, tlie mean was o7°‘5, or 
1° above the average, while for August, 1902, the mean was 53° ’9, or 2^° below the average. 
The nearest station to the Conon basin lochs from which observations are available is 
Inverness, and the mean temperature there for July, 1901, was 61°-0, or 4° above the long- 
period average, while for July, 1902, the mean temperature was 45°-4, or 3^ below the 
