24 ANNALS OF SCOTTISH NATURAL HISTORY 



Edinburgh for a time, taking his M. D. degree in 1812, so that the 

 mountains he refers to are probably the Pentland Hills. His 

 type specimen, still preserved in the British Museum, is marked 

 " Scotland." 



At the present day this is without doubt the most abundant and 

 generally distributed of all our False-scorpions, occurring from the 

 edge of the tide to the inland moorlands and mountains. At the 

 mouth of the Avon, between Stirling and West Lothian, it lives 

 among the refuse at high-water mark ; and in Mid and East 

 Lothians tenanted nests of the species situated in similar positions 

 have come under my notice in the autumn months. In woods O. 

 muscorum lives among the masses of dead leaves lying in damp 

 situations, and on open ground it is obtained in abundance under 

 stones. I have taken it among damp earth on the Castle Rock in 

 Princes Street Gardens, Edinburgh, and on the slopes of the 

 Pentlands at Dreghorn. Inland, its area of distribution ranges over 

 the woodlands and even the open moors, but, so far as my observa- 

 tions go, it stops short at the border of the true mosses. In the 

 wild forest of Rothiemurchus it is quite common ; and in some 

 parts of Scotland it ascends to a considerable height, being numerous 

 for example on the range that lies between Glen Ogle and Edenchip 

 Glen in Perthshire to a height of 1500 feet at least, and on the 

 slopes of Ben Cailleach in Skye. It occurs also under the bark of 

 trees, both living and dead, and is the only species I have so far 

 found in such situations in Scotland. 



Throughout the middle and the southern portions of Scotland 

 its distribution will probably prove to be universal. Mr. James 

 Waterston informs me that he has found the empty nest on the 

 island of Arran, and I have examined tenanted nests on Island 

 More, a small island in Loch Fyne, near Lochgilphead, and on the 

 Maiden Island, Oban ; I have also seen this species on the Rough 

 Island, in the Solway Firth. Mr. Wm. Evans, in his notes, calls 

 the species " ubiquitous." Unless, however, the nest is known, the 

 real abundance of the species will never be suspected ; as an 

 illustration of this I may mention that during a fortnight in Argyll 

 in July 1901, although seventy-one nests most of which were 

 already empty came under my notice, only one solitary individual 

 was observed moving free. 



Obisium muscorum is abroad nearly the whole year round ; the 

 only month in which I have not found it active is October, but 

 this gap is most likely due to insufficient observation alone. Its 

 habits, during a free state, do not present any features conspicuously 

 different from those of its allies. It is more active than the blind 

 species, but less so than Chthonitts rayi. Its degree of activity 

 depends greatly on the place of its abode, those under stones being 

 much less active than those living among dead leaves and brackens. 



