THE FRESH- WATER LOCHS OF SCOTLAND. 193 



dozen species of Desmids were observed, including Staurastrum longis- 

 pinum and S. gracile, var. bulbosum. 



Loch Owskeich. The fauna was much richer than that of Loch 

 Bad a' Ghaill, with which, from position and size, it is best comparable. 

 Diaptomu* yracilis and D. laciniatus were both present. The Daphnia 

 was D. galeata. There were many filamentous Algae and Desmids, 

 among which occurred Staurastrum Brazil iense. 



Loch Skinaskink. The plankton was very rich, and, notwithstanding 

 the large size and considerable mean depth of the loch, resembled that 

 of a shallow loch in the great numbers of Rotifers, Desmids, and 

 Protozoa. There were two species of Diaptomus, D. gracilis and D. 

 laciniatus, and two of Daphnia, D. lacustris and D. galeata. Among 

 the Rotifera were two species which, though pelagic, are not usual in 

 large lakes, viz., a Synchceta and a Plcesoma. The Desmids included 

 Staurastrum Brazil ie?ise and S. ophiura. 



Loch Fionn. This loch, though long, is so narrow as to be little 

 more than an expansion of the river. When in spate, as on the occasion 

 of the visit of the Lake Survey, there is a decided current down the 

 loch. As would be expected in the circumstances, life was very scarce 

 and of few species. Two forms of Bosmina were present, B. obtusirostris 

 and its variety B. longispina. 



Loch an Tuirc. Entomostraca were numerous, but of few species. 

 Rotifera were scarce. Filamentous Algae were abundant, but there 

 were few Desmids. 



Loch Beannach. Organisms were not very abundant. Only the 

 commonest pelagic Entomostraca were present. Rotifera were more 

 numerous, including, in addition to the usual pelagic species, Gastropus 

 stylifer and a species of Plcesoma. 



Loch na Doire Daraich. The very abundant fauna of this loch 

 closely resembled that of the adjacent Loch Druim Suardalain, the 

 most notable difference being the more numerous Rotifera. Among 

 these were Floscularia pelagica, Triarthra longiseta, Pterodina patina, 

 Copeus cerberus, Dinocharis Collinsii. Among the numerous Desmids 

 were Micrasterias furcata, M. j)innatafjda, Staurastrum grande, and 

 S. longispinum. 



Loch, Druim Suardalain. This shallow loch had the richest fauna 

 found in the lochs of the district. The flora was also very rich. About 

 a dozen species of Rotifera were seen, including Callidina Brycei. 

 Over thirty species of Desmids occurred, among which were Staurastrum 

 grandr, S. ophiura, and S. serangulare. There was nothing among 

 the Entomostraca calling for remark, only the commoner pelagic and 

 shallow-water species being observed. 



Loch Maol a' Choire. Crustacea were very abundant, including a 

 species of Gammarus. Diaptonnis Wierzejskii was the only Calanid 

 observed. It was in a collection from this loch that the species was 



o 



