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Part III. — Seventeenth Annual Report 



Diapiomus gracilis was more plentiful in the gatherings from this loch 

 than in those from the other two. It was, however, less common in the 

 December gatherings than in those for the other months. 



Diaptomus hircus, Brady, was also moderately frequent, except in the 

 gatherings for August 1897. 



Cyclops strenuus was one of the more common species in this loch ; 

 while Cyclops viridis only occurred once. 



Holopedium yibberum has already been referred to. 



Daphnia yaleata was quite common in the gatherings from Loch Lochy, 

 with the exception of those collected in August 1897. The Daphniw in 

 the gatherings from this loch were similar to those observed in Loch Ness ; 

 but those with the head strongly helmeted were less in evidence here 

 than in Loch Oich. 



Bosmina lonyispina. The Bosmince of Loch Lochy, like those of Loch 

 Oich and Loch Ness, exhibited a certain amount of variation in size and 

 in the length of the antennules and of the posterior spines, and it may be 

 that they include one, or perhaps two, other species besides B. lonyispina. 

 That, however, appears to be the typical form, and I prefer meantime to 

 consider the others as " varieties." 



Polyphemus was one of the less common Entomostracans in Loch Lochy, 

 and here, as elsewhere, appeared to be susceptible to seasonal changes. 



Bythotrephes was more plentiful in the gatherings collected in August 

 and October 1898 than in those collected previously, and, though it 

 occurred in all of them from the surface down to seventy fathoms, it was 

 scarcer in those collected in deep water. 



Leptodora differed little in its distribution from Bythotrephes, except 

 that it was not observed in the gatherings collected either in December 

 or January, nor in those collected below fifty fathoms. It was common 

 in one or two of the surface gatherings. 



General List of all the Species of Crustacea and Mollusca that 

 are recorded from the various lochs referred to in the 

 Preceding Pages, together with Names of the Lochs in 

 which they were observed. 



An x under the name of a Loch indicates that the species was obtained in it. 



Names of the Species. 



Loch Lomond. 



Loch Arklet. 



Loch Katrine. 



Loch Achraj-. 



Forfar Loch. 



Loch Leven. 



Duddingston Loch. 



Loch Doom 



Loch Ness. 



Loch Oich. 



Loch Lochy. . 



CRUSTACEA. 

























Amphipoda. 

























Gammatus pulex (Penn.),- 







X 





X 



X 



X 



X 









ISOPODA. 

























Asellas aquaticus (Linn.), 

























