Land and Freslmater Shells found in Caithness. 163 
new species, tliey have greatly assisted in extending locali- 
ties, and from their quick observation I have great hopes. 
At present, until more facts have been collected, it is not 
desirable to enter on a comparison of this district witli 
others, nor anything else beyond giving the numbers stated 
in three local lists which I have. First, Mr Alder's " Cata- 
logue of Northumberland and Durham ; " that of Aberdeen, 
by the late Professor Macgillivray, in the work on " Dee 
Side ;" and that of the " Province of Moray," by the Kev. 
Dr Gordon, published in the " Zoologist." 
Northumberland and Durham, 80 species. 
Aberdeen, .... 53 ,, 
Province of Moray, . . 46 
Caithness, .... 30 „ 
I would here remark, that when the well-known fact of 
the diminution of the pulmonifera as we proceed north is 
taken into consideration, with the little examination made, 
and the small area included in our list — viz., Caithness 
only — there is little cause for either surprise or dissatis- 
faction, and it only requires more eyes and willing hands of 
the lovers of Carnabia to be set in motion, to increase the 
number for a supplementary list. When this is the case, 
I hope to return to the subject. For the present be pleased 
to accept of this as an instalment only. 
N.B. — Those marked with an asterisk (*) have also been 
found in the marls of Caithness. 
* Sphcerium corneum, Brickigoe, River of Wick, &c. 
Pisidium nitidum, River of Wick, and Loch of Sarclet. 
Unio margaratifer, River of Wick — rather plentiful, 
*■ Valvata piscinalis, Loch of Brickigo, and River of Wick . 
* Planorbis nautilus, Reiss, and near the Mill of Thrumster. 
1 * P. albus, very rare, Loch of Brickigo. 
I P. glaber, Reiss, and near the Mill of Thrumster. Mr Jeffreys 
1 says : — " These are finer than usual, indeed very near as large as some 
Mr Bridgman found near Norwich. 
Planorbis spirobis, same localities as the last. Jeffreys records it as 
" from the Moray Firth district to the Channel Islands." 
* P. contortus, River of Wick and Loch of Brickigo. 
* Linncea pereger, Wick, Ulbster, &c. &c. 
L. truncatuluSf Southhead, Wick, &c. 
iAncylus Jluviatilis, plentiful in many localities. Jeffreys says — 
VOL. III. Y 
