CHAP. xvin. VARIETIES IN ROSES. 311 



boulder clay. Drains and improvements on the soil atop 

 of the clay sent a perpetual stream of water over the 

 roots of the plants. In two years they have so altered 

 that I can hardly believe my eyes. . . . All the roses 

 growing wild in Caithness may have come from one 

 stock ; but from what particular stock I cannot tell." 



We merely quote these remarks from Dick's letters 

 to show the acuteness and accuracy of his observations. 

 He never missed any peculiar characteristic of a plant. 

 He had also a wonderful memory about it, and could 

 contrast its appearance during one season with its 

 appearance in another. It was the same with all his 

 natural history observations. In one of his letters to 

 Dr. Meiklejohn he refers to the mischief done to the 

 fields of Caithness by a particular grub. " Speaking of 

 grasses," he says, " reminds me of the crops of Caithness. 

 They are desperately cut up by a worm, of what par- 

 ticular species I'll not say, but the grub of 'Daddy 

 Longlegs ' (Tipula oleracea) has certainly the predomi- 

 nance. It has drawn after it whole flocks of starlings, 

 who are driving a brisk trade. But it would require 

 millions of them to stay she plague. Indeed, the work 

 of ruin is already done. It is pitiful." 



