242 ANNALS OF SCOTTISH NATURAL HISTORY 



ioo. S. quadrangulare, Breb. — Very rare. Aberdeen, — at Birse- 

 more Loch, near Dinnet, and Dalbagie. 



101. S. Reinschiij Roy. — General, but scarce. With zygospores, in 



Argyle, Glen Coe (Mr. Archer). 



1 02. S. refiandum, Perty. — Very rare. Aberdeen — Glen Callater. 



103. S. rhabdoplwrum, Nordst. — Extremely rare. Aberdeen (or 



Forfar ?) — table-land north-west of Canlochan. 



104. S. rostellum, n. sp. — Rare. 



Small, slightly longer than broad, broadly oval, constriction 

 shallow, opening wide : semi-cell flatly oval, spiny, spines small, 

 the one next the constriction rather larger and directed 

 downwards, more prominent at one angle owing to a peculiar 

 twist in the semi-cell giving it a considerable resemblance 

 to a bird's beak, a number of small spines (about 14) are 

 arranged round the margin of the semi-cell and 2 to 3 rows 

 within the margin ; end view quadrangular, with sides con- 

 cave, spiny, and angles a little produced, one more promi- 

 nent on account of the twist. Membrane smooth ; isthmus 

 broad. Length, 31-33/x; breadth, 29-31 /jl; isth., 13-14/*. 



It seems unnecessary to compare this species with any 

 other (our Plate III. fig. 3). 



Ross — near Tain and Strathpeffer ; Inverness — Skye, at 

 the head of Glen Sligachan ; Aberdeen — many localities from 

 Scotston to Girnoc ; Kincardine — Rickarton ; Perth — Glen 

 Garry; Argyle — Glen Coe. 



105. S. rugulosum, Breb. — Rare. Ross — near Strathpeffer; Kin- 



cardine — on the north side of Cairnmonearn. 



106. S. saxontcum, Bulnh. — Rare. Aberdeen — near Mill of Maiden- 



craig, Haughton, Tillyfour, old channel of Dee below Aboyne, 

 near Dinnet School, Koynach Moor in Cromar, Castleton, 

 Braemar; Kincardine — near Durris Bridge, Cammie, Dal- 

 brake, Slack of Birnie ; Forfar — Lundie Bog, Easter Ogil in 

 Fern {pur Plate III. fig. 10). 



107. S. saxonicum, Reinsch. — Very rare. Aberdeen — Powlair in 



Birse, and Dinnet. 



This is probably nothing more than a form of S. aculeatum, 

 Ehr., but it is a remarkable one. I have seen few examples. 



108. S. scabriwi, Breb. — Not common. Shetland, Sutherland, 



Ross, Moray, Aberdeen, Kincardine, Forfar, Perth, Fife, 

 Argyle, Arran. With zygospores, in Aberdeen near Cambus- 

 o'-May. They are globular, sometimes slightly oblong, with 

 short stout spines, 3-4-fid at the apex. About 10 to 13 

 visible round the margin. Diameter without spines, 32-35 fi ; 

 length of spine, 5-6 //. 



