A YORKSHIRE NATURALIST jyj 



numerous thin transverse separable layers, Medulla? 

 of till* type are found in the white jasmine, in the 

 common walnut, and some others of the Juglandaceae, 

 and in the balsam pine of Canada, The wood and 

 bark of my specimens were of the common quasi- 

 coniferous form so frequently met with in the car- 

 boniferous rocks, then known by the name of 

 Dadoxylon, and now regarded a* being of a gymno- 

 spermous type, half coniferous and half cycadean. 

 This successful investigation brought me back in 

 thought to my old subject of fossil botany, and 

 two casual incidents led the way to my devoting my 

 leisure hours to pabeo-botanical subjects during the 

 remainder of my life. 



Early in the fifties, when I was commencing in 

 an unsystematic way to grind down fragments of 

 various objects for microscopic investigation, I found 

 in a drawer of my cabinet a portion of a Calamite 

 that had been extracted from one of the ironstone 

 nodules of the coal-measures, I was not at that 

 time provided with a lathe or any other sort of 

 cutting or grinding machinery ; but as the calamite 

 presented indications that some structure might 

 be found in it, I chipped off with hammer and chisel 

 such fragments as appeared suitable, and ground 

 them down on a flagstone, obtaining nine curious 

 sections, showing the structure of a woody zone 

 where it was in immediate contact with the 

 medulla. 



Having then no intention of making any special 



