186 BRITISH DESMIDIACE^:. 



ENGLAND.- -Near Bowness, Westmoreland (Bissett). 

 Cowside Beck near Arncliffe, W. Yorks ! Epping 

 Forest, Essex ! 



WALES. --Capel Curig, Carnarvonshire (Roy). Holy- 

 head (in pond) ! 



SCOTLAND.- Ross, Inverness, Aberdeen, Kincardine 

 (zygospores from Muchalls), Forfar, Perth, Stirling, 

 Arran, Wigtown (Roy $ Bissett). 



IRELAND.- -Errigal, Donegal ! Derryclare Lough, 

 Galway ! Dublin and Wicklow (Arclu j r). Slieve- 

 commedagh and Slieve Donard (up to 2000 ft.), 

 Down ! 



Geoc/r. Distribution.- France. Italy. Sweden. 

 Bornholm. United States. 



There is a considerable resemblance between C. Sportella 

 and C. Corbula, but the former is larger and differently 

 ornamented. The granules of C. Sportella are irregularly 

 disposed and the granulated tumour in the centre of the 

 semicells is relatively smaller ; in fact, this tumour is some- 

 times almost wanting and the granules on it are much 

 reduced. 



We have never met with any specimens with a dilated apex 

 such as is indicated in Brebisson's original figure, but this 



O O ' 



figure, like many others bv the same author, is most wretched. 



' / 



The zygospores have been obtained by Nordstedt in Sweden 

 and by Messrs. Roy and Bissett in Scotland. 



Yar. subimdum rr. nov. (PI. LXXXII, fig. 14.) 



Cells proportionately longer (almost 1 J times as long 

 as broad) ; semicells more pyramidate, basal angles 

 not quite so rounded, central granules and tumour 

 entirely absent. 



c- 



Length 51/x; breadth 41 ^ ; breadth of apex 22 ^ ; 

 breadth of isthmus 14*5 JJL. 



ENGLAND .--Ogden Clough, W. Yorks ! 



This variety occurred in abundance among' mosses on 

 dripping rocks. As in the type, the cell-wall is finely 

 punctate. 



