170 ANNALS OF SCOTTISH NATURAL HISTORY 



examples of three slugs : Arion subfuscus (one), A. minimus 

 (two), and Limax ci?iereo-niger (one, from Loch-an-Eilan). 

 While recording these, I take the opportunity of mentioning 

 several examples of Hyalinia alliaria and a few of Vitrina 

 pellucida collected on the 12th of September 189 1 at Nairn, 

 which Mr. Evans has been good enough to allow us the sight 

 of. The eleven additions now brought forward raise the 

 total number of authentications for Easterness to 36 species. 



ON SCOTTISH DESMIDIE.E. 



By John Roy, LL.D. 

 ( Cotitinued from p. 1 1 1 . ) 



Plate IV. 



DESMIDIE^E (Kg.), De Bary. 

 DESMIDIUM (Ag.\ De Bary. 



1. D. Aptogonum, Breb. — Not common. Sutherland, Aberdeen, 



Kincardine, Forfar, Perth, Argyle, Fife. 



ft E/irenbergii, Rab. — Rare. Aberdeen — pools beside 

 Birsemore Loch ; Kincardine — near Banchory. 



2. D. cylindriaun, Grev. — General. With zygospores, at Slew- 



drum in Birse. 



3. D. quadratinn, Nordst. — Very rare. Aberdeen — at Slewdrum 



in Birse. 



4. D. Swartzii, Ag. — General. With zygospores, at Tomachar, 



in Aberdeen. 



/3 quadrangidatum, Ralfs, — Rare. Aberdeen — Scotston 

 Moss (Mr. P. Grant and Dr. Dickie), Heughhead 

 near Aboyne, Black Moss in Cromar, Braemar 

 (Mr. W. West). 



HYALOTHECA, Kg. 



1. H. dissiliefts (Sm.), Breb. — General. 



P bidentula, Nordst. — Common. 



y tride?ihda, Nordst. — Common. Zygospores are abundant. 



2. H. mucosa (Dillw.), Ehr. — Not common. Inverness, Aberdeen, 



Kincardine, Perth, Argyle. 



p ?}ii?ior, n. var. — Very rare. Only half the usual diameter, 

 9-12 [x. Aberdeen — plentiful in a small pool at the 

 west end of Birsemore Loch. 



