HOPS niOSSOM. 169 



exhibit so many points of minute adaptation to its own 

 peculiar habitat, nor would it be so distinctly marked off 

 from its other divergent relatives on either side. While 

 all of the nettles arc mere soft herbs, and most of the 

 pellitories arc slightly shrubby weeds, the hop has ac- 

 quired the habit of producing a stout perennial root- 

 stock ; from which each spring it sends up wonderfully 

 long annual stems, that climb to an immense height over 

 the poles in cultivation or over bushes and thickets in the 

 wild state, dying down again entirely with the approach 

 of winter. I know nothing more marvellous in the way 

 of growth than the rapidity ^vith which these lithe bines 

 curl spirally up the bare poles in early summer — at first 

 on the strength of material laid by in their buried root- 

 stocks, but afterwards b)' the rapid assimilation of aerial 

 food from the surrounding atmosphere. As one watches 

 the slender young sprays and the graceful fivc-lobed 

 heart-shaped leaves, rendered so singularly like those of 

 the wholly unconnected grape-vine by exact similarity 

 of situation and function, one can almost see them with 

 the eye of scientific faith drinking in the carbon visibly 

 from the air around by the numerous thirsty pores on 

 their under surface. 



Everything here has been obviously designed for the 

 climbing habit. The rough hairs w^hich in the nettle 

 serve as glandular reservoirs for a deterrent poison are 

 transformed in the hop, by a thickening of their base, 

 into recurved prickles, which serve as hooks to aid the 

 plant in hanging to the poles, or rather, in the wild 

 state, in clambering over small trees and hedgerows : for 

 of course the original evolving bines could never have 

 contemplated their descendants' future domestication in 



