THE FALSE-SCORPIONS OF SCOTLAND 27 



this late-laying group is probably quite a different set of creatures 

 from the spring- laying group. So far as I have observed very 

 few individuals take part in the autumn laying. August 1 2 is the 

 date at which I have found this autumn brood able to begin a 

 free life. 



In the yearly cycle of O. muscorum's history, autumn is marked 

 off as the time for moulting. The presence of False-scorpions' 

 remains in nests in autumn and winter had been puzzling me a 

 considerable time, and the explanation of moulting did not occur to 

 me till I discovered the creatures in the act. While endeavour- 

 ing to discover Chelifer latreillii under the bark of trees at Aberlady 

 on September 26, 1903, I came on the nests of O. muscorum under 

 the bark and between different layers of the bark. Several were 

 opened without result, but ere long occupied nests were discovered 

 containing specimens of O. muscorum in process of casting their 

 skins. One creature was caught in the act, and in another case the 

 living muscorum was resting in the nest beside its cast skin. In t the 

 case of the half-moulted individual the liberated head was facing in 

 the opposite direction from the discarded head skin, but the crea- 

 ture was motionless and may have died in the process of moulting. 

 In the cast-off moult found in the other nest there was no trace of 

 the hind-body, but the fore-body remained nearly intact, with the 

 basal joints of the legs and the position of the eyes prominently 

 marked ; the pedipalps attached were perfect to the very tips of the 

 pincers, and the skin of the chelicene was observable inside the 

 skin of the fore-body, having been drawn into that position during 

 the animal's retreat. As usually happens with all creatures after 

 their moult, O. muscorum shows very little colour, with only a faint 

 greenish tinge on the carapace, pedipalps, and legs, and a dirty 

 brown abdomen ; it is also very tender and listless and not at all 

 anxious to move. As soon as its skin hardens sufficiently, the 

 creature leaves its nest and resumes its active life. 



The period of moulting is not constant. The normal period is 

 August and September, but even as early as June 21 I have seen 

 half-grown light-coloured individuals inside nests which, in my 

 opinion, they were using for moulting purposes. 



One other question remained for solution, "Does O. muscorum 

 hibernate ? " My opportunities of looking for these creatures in 

 winter had been so meagre that I could not infer from the absence 

 of any personal records in my note-books that they do not hibernate. 

 I rather inclined to believe that they did, and during the winter of 

 1903-4 in Ayrshire, when laid aside from active work, I set myself 

 to solve this problem. I opened many nests of the species, only to 

 find them either empty or containing the cast skins of last autumn's 

 moult, but at length on March 18, 1904, I obtained what I sought. 

 On that day I found a very immature specimen inside its nest alive 



