158 



Part III. — Seventeenth Annual Report 



were observed in both of these latter gatherings. Diaptomus was much 

 more common in the gathering collected in November — especially in that 

 collected with the fine net — than in any of the others. Cyclops strenuus 

 was more or less frequent in all the four gatherings. The annexed Table 

 contains the names of all the species captured in the tow nets. 



Table containing Names of Species and Dates when Captured 

 in Forfar Loch. 



(Ab., abundant ; c, common ; fr., frequent ; f., few; r., rare ; 0, none.) 





Dates. 



Names of the Species. 



1897. 



1898. 





Nov. 3. 



March 4. 



June 16. 



Sept. 15. 



COPEPODA. 











Diaptomus gracilis, G. 0. Sars, 

 Cyclops strenvus, Fischer, 

 ,, viridis ( Jurine), 



f. (ab. in 

 fine net. ) 

 fr. 



0 



r. (fr. in 

 tine net.) 

 fr. 



r. 



f. (fr. in 

 fine net.) 

 f. (fr. in 

 fine net.) 

 0 



fr. 

 fr. 



0 



,, albidus (Jurine), 



0 



r. 



0 



0 



Cladocera. 











Ceriodaphnia reticulata (J 'urine), - 



0 



0 



0 



r. 



Simocephalus vetulus (Miiller), 



0 



! r * 



0 



0 



Daphnia lacustris, G. 0. Sars, 



ab. 



ab. 



ab. 



ab. 



Chydorus spluericus (Miiller), 



0 



0 



0 



r. 



The gathering collected with the fine net in September contained 

 numerous Ceratium, Diatoms, Desmids, Nostoc, and others. So numerous 

 were these minute forms of animal and vegetable life that they made the 

 water obscure, so that it had the appearance as if fine dust were held in 

 suspension. These minute forms may be reported on later. 



The Ceriodaphnia were represented chiefly by females with pseudova, 

 but there were also a few ephippial females and one or two males. The 

 Daphnice consisted chiefly of females with pseudova; and besides the males 

 already referred to as having been observed in the June and September 

 gatherings, there were also a few ephippial females present in these 

 gatherings. Very few creatures other than the Entomostraea, and the 

 Infusoria and Micro-algae already mentioned, were observed in the tow-net 

 collections. 



The SJiore and Bottom Fauna collected chiefly with the Hand-Net. 



The Crustacea, Mollusca, etc., captured with the hand-net were fairly 

 numerous and varied, and amongst them several rare forms were observed. 

 These will be more particularly referred to in the sequel. 



It has been remarked that, besides the four occasions on which the loch 

 was tow-netted, the shores had on a previous visit^-viz., in July 1897 



