OX THE CRYPTOGAMIC BOTANY. XXIX 



As every bryologist is aware this moss, at the time of the publi- 

 cation of Wilson's work on British mosses, had been found in three 

 spots in England and in one in Abyssinia, and nowhere else; a 

 fourth was found in 1862 on sandstone in Lennoxtown Woods, where 

 it fruits freely in March and April. The area of growth is very 

 restricted, not embracing more than 3 or 4 square yards; but it keeps 

 its hold notwithstanding adverse circumstances, for rocks of this 

 formation are perhaps the least favourable to the growth and 

 development of mosses and lichens of almost every kind. 



Didymodon recurvifolius (Tayl.), on grassy slopes midway up Ben 

 Voirlich from Loch Lomond, is due to the late Mr. A. M'Kinlay. 

 This is now believed to be the only station in existence for this moss, 

 as that on Knockavohila in Ireland is extinct. Apart from the 

 statement of Mr. M'Kinlay himself to the effect that he had no fear 

 of the plant becoming extinct on Ben Voirlich, I feel inclined to 

 maintain that this habitat has shared the fate of the Irish one, for 

 on every occasion of a visit to the mountain, I have devoted a share 

 of my time to the rediscovery of the moss, but hitherto without 

 success. This is to be deplored, inasmuch as the death of the dis- 

 coverer precludes the possibility of any more definite information 

 being arrived at as to the exact place of growth. 



Myurium Hebridarum (Sch.), detected for the first time in North 

 Uist by the late Dr. C. Smith of Inverary, has again been found in 

 great luxuriance in the original station. A second station has been 

 revealed by the Eev. Dr. H. Macmillan on the shores of Loch 

 Coruisk in Skye. The only other stations for it are in the Canary 

 Islands and Azores, from the latter of which I have it in fruit 

 gathered by Mr. Moseley of the Challenger Expedition. 



A slender clue is given in this instance, as well as in another 

 already stated, as to the former disposition of the land along the 

 great Mid Atlantic ridge ; but I forbear to follow it up, although 

 there are other botanical examples which go to strengthen the 

 theory of a continuous land-surface along this ridge or bank. 



4th. Other instances of restricted areas of growth might be men- 

 tioned; but as such are common to other districts I refrain from 

 multiplying examples. Three others may, however, be adduced as 

 indicating what may be termed initiatory stages of specific develop- 

 ment, in marked contrast to those previously given, viz., Ortho- 

 trichum Shawii on an old ash-tree near Dailly and Campylopus 

 Shawii from North Uist, both due to Dr. J. Shaw, now of Cape 

 Town, South Africa. There is little doubt that these are offshoots 

 from 0. cupulatum on the one hand and C. alpinus on the other, 

 and, accordingly, tend towards the Darwinian theory of development, 

 more especially as their botanical characters are quite appreciable, &c. 

 A third is Didymodon Daldinianus, clearly an offshoot from D. 

 cylindricus, which, besides, is found sparingly throughout our High- 

 land glens, and in fruit in two of these, viz. Campsie, the original 



