NATURAL HISTORY SOCIETY OF GLASGOW. 3 



shales in connection with the ironstone a rich harvest of organic 

 remains was formerly obtained in the old shale banks and in the 

 bed of the stream. So abundant were crinoid stems then that the 

 stream was known to the people of the district as the " witch whorl 

 burn," these remains being known in various districts of the 

 country as pulley stones, screw stones, fairy stones, or St. Cuthbert's 

 beads, before their real organic structure was understood. Of 

 recent years these fossiliferous shale banks have become very much 

 overgrown by whin, thorn, broom, and rose bushes, as well as by 

 grass and herbage, and few good exposures of the shale are now to 

 be seen ; still, by digging into the banks, by examining the bed of 

 the stream, or by washing the weathered shale for the smaller 

 organisms, many interesting specimens are yet to be found by the 

 patient investigator. Upwards of 150 species of Carboniferous 

 fossils have already been recorded from the strata of Craigenglen, 

 the list having been much enriched during recent years by members 

 of the Society in their search for the microzoa of these old deposits. 

 All the groups of fossils characteristic of the limestone districts of 

 other portions of Scotland are represented in the strata of the glen 

 to a large extent, while the number and variety of spiral or 

 univalve shells in a fine state of preservation has seldom been 

 equalled in any other beds of the same age. 



In connection with the marine deposits of Craigenglen, it was 

 pointed out by Mr. John Young, F.G.S., that here there are 

 alternations of fresh- water deposits with those formed or laid down 

 over the old sea bottoms, the fresh-water beds being characterised 

 by the absence of marine organisms and by the presence of entomo- 

 straca, and fishes, found in similar strata in other portions of the 

 Scottish coal-field ; such alternations of marine and fresh- water 

 conditions implying extensive upheavals and depressions of the 

 earth's crust during the formation of the limestone series. 



Craigenglen having a southern exposure, and being sheltered from 

 the east and west winds, affords a fine field for the botanist. In 

 the early months of the year the slopes are brilliant with a profusion 

 of primroses and other spring flowers, and farther in the season the 

 Adders-tongue fern, Ophioglossum vulgatum. may be found in 

 abundance on the eastern bank. A distinctive feature of the glen 

 is the profusion of rose bushes, which flourish more particularly on 

 the right bank, the prevalence of Rosa villosa imparting a striking 

 and picturesque aspect to the view. The long, straight stems of 



