286 Life-histories of Northern Animals 



the water and mud about him mixed into a complete mortar, 

 which changes his colour, and drips in streams from every part 

 of him as he rises up upon his feet a hideous monster of mud 

 and ugliness, too frightful and too eccentric to be described." 



This practice seems to have been much more popular with 

 the bulls than with the cows — a fact which seems to prove that 

 the flies alone were not the cause of it. The bulls were more 

 heavily clad with wool on the fore parts and suffered more, 

 therefore, from the heat. Also they gathered more of the prickly 

 seeds that are an active irritant of the skin. Chief among these 

 on the northern Plains is the ** spear grass" or "wild oats" 

 (Sttpa spartea). In July it seeds abundantly. Each seed is 

 like an oat, with a sharp corkscrew point and a long barley awn, 

 but set everywhere with fine bristles pointing backward. 

 When this contrivance touches the wool of a Buffalo, its barbs 

 at once cling, and by a complete hygroscopic mechanism, 

 first carefully studied by Miller Christy,®^ it revolves seven or 

 eight times in an hour, boring through the wool and finally reach- 

 ing the skin. Every prairie man remembers the sharp prick of 

 the spear-grass — first its corkscrew penetrates his clothing; then 

 it attacks his person. Every sheep-owner, too, can testify that it 

 keeps on boring, even through the skin, till an angry, irritating 

 sore is produced. This aggressive plant was, no doubt, one of the 

 plagues that drove the Buffalo to the wallows. A proof of this, 

 as Christy points out, is seen in the fact that the old wallows are 

 rimmed about with an unusually thick and vigorous growth of 

 spear-grass. The newer generation calls them *' fairy-rings." 



RUBBING The wallow was not the only offset. Rubbing places were 

 in great demand. It is well known that the posts of all the 

 first telegraph-lines across the Plains were thrown down, again 

 and again, by the Bufifalo rubbing against them. Even when 

 the poles were protected by sharp spikes, the big brutes were 

 not deterred from availing themselves of these delightfully con- 

 venient scratching posts — they were, indeed, attracted rather 



^* On the power of penetrating the bodies of animals possessed by the seed of Stipa 

 spartea. Read before the Linnasan Society, London, February 21, 1884. 



