1 62 [Proc. B. N. F. C, 



one, of mountain tops rising amidst an expanse of moorland and 

 bog, interspersed with patches of cultivation. Here a " standing 

 stone," or " dollan," marks the site of some forgotten event, or 

 the death of some hero of pre-historic times. The Sallagh Braes 

 constituted the next item in the programme, but owing to the 

 roughness of the ground, and an accident to one of the vehicles, 

 which caused an embarrassing delay, it was only the more active 

 of the party who were able to carry it out. These, however, 

 pushing hastily across the intervening boggy ground, were 

 rewarded by finding themselves on the edge of this magnificent 

 amphitheatre of cliffs, a grand piece of scenery which too many 

 of our coast tourists miss. This striking basaltic range consti- 

 tutes a habitat for the rarer indigenous plants, and they have 

 been long resorted to by those interested in the native flora. 

 Nothwithstanding the limited time, some scarce plants were 

 found. The filmy fern {Hymenophyllum Wilsont) was met 

 with, growing in moss-like patches on the shady rocks, and 

 along with it the bladder fern {Cystopierisfragilis). One of the 

 rarer hawkweeds {Hieracium anglicum) was seen in small 

 quantity on the steep rocks, and Alsine verna was in abundance. 

 At the same place the very rare wild vetch ( Vicia orobus) still 

 holds its ground, this is one of the most interesting plants of the 

 district. It is evident that any one having time for a thorough 

 search would be rewarded with specimens of many other 

 botanical rarities. Whilst the botanists were thus engaged, two 

 or three of the geological enthusiasts had bolted off to the 

 furthermost extremity of the cliffs, where, close to the abrupt 

 and craggy summit of Knock-dhu, are to be seen two of the most 

 remarkable trap dykes in the province. Trap dykes are plen- 

 tiful enough, for one can hardly walk a mile down a stream 

 any where in the North-eastern counties without coming on 

 half a dozen of them ; but these of Knock-dhu are unique. 

 They cut at right angles to a lofty cliff of the basaltic rocks, 

 which have weathered away so as to leave a steep gully or ravine 

 at each side of the dyke, and, in the case of the larger one 

 especially, the dyke is to be seen towering up thirty or forty 



