140 Proceedings of the Royal Society of Edinburgh. [Sess. 
Juncus lamprocarpus, J. acutiflorus, J. effusus, Caltha palustris, Heleocharis 
palustris, H. multicaulis,Menyanthes trifoliata, Comarum palustre,Lysimachia 
vulgaris, (Enanthe crocata, Lythrum Salicaria, Lycopus europseus, Spiraea 
Ulmaria, Schoenus nigricans, Radicula officinalis, Hydrocotyle vulgaris, 
Scutellaria galericulata, and Polygonum Hydropiper. Eupatorium canna- 
binum occurred chiefly at the islands, on some of which Osmunda regalis was 
abundant. Bryophytes on the shore, with the exception of Hypnum 
cupressiforme, which covers rocks, and Sphagnum sp. in peaty places, were 
not abundant. 
Gastle Loch is J mile west of the last mentioned, which it much 
resembles in size and general features. It is 16 feet higher than Mochrum 
Loch, into which its north-eastern effluent flows. There are a few trees at 
the north end and on one of the islands, which also has upon it the remains 
of a small castle. The surrounding country is bare, open moor. This loch 
is studded with numerous bare, rocky islands, the largest being occupied by 
hundreds of cormorants, which breed there. The shores are rocky or stony, 
and the bottom is rocky nearly everywhere. The water is clear, like that 
of Mochrum Loch, and the average depth is from 6 to 8 feet, with a maximum 
of 11 feet. I dredged a dozen or more of the less rocky places and examined 
many other parts of the bottom, but could obtain no plants from the water 
save Fontinalis antipyretica and F. squamosa, which abound on the rocks. 
The bottom appears to be quite destitute of plants, excepting the two species 
just enumerated. This is remarkable, especially when the adjoining 
Mochrum Loch has such an abundant aquatic flora. Mr David M'Dowall, 
the keeper, informed me that he had never seen any plants upon the net 
when netting this loch. The water was remarkably free of plankton 
organisms, the tow-net gathering extremely little (end of August), but Mr 
M‘Dowall told me that in early summer the water is thick and green with some 
organism that dies away towards the end of July. Perhaps the presence 
of this organism in the spring accounts for the absence of plants in the 
water. The scanty vegetation of the rocky shores was of no particular 
interest, being similar to that of Mochrum Loch, but less abundant. 
Lythrum Salicaria and Phalaris arundinacea were the most plentiful species. 
Fig. 60 illustrates this loch, with Mochrum Loch in the distance. 
On Anabaglish Moss, to the north-west of Castle Loch, there are a 
number of small lochans of some interest because of the abundance of their 
vegetation, which includes some unusual species. Figs. 61 to 64 illustrate 
four of these tarns ; the legends appended to the illustrations afford sufficient 
description. 
[Monreith Lake, near Port William, is entirely surrounded by wood 
