ii6 The Ottawa Naturalist. [September 



reached by a series of slopes and ** benches," the level land at the 

 bottom never reaching a mile in width and seldom half a mile. It 

 is on these slopes with a southern aspect that plants characteristic 

 of an arid climate are found, chief among them a cactus, [Opuntia 

 Missourietisis?) which is quite common. The grasses are those of 

 the driest parts of the southern prairie region, 



The prairie on the plateau above would delight the eye of 

 those who admire large masses of one color, for abundant as 

 individual flowers are the number of species is strangely small. 

 Hundreds of acres will be seen on which a single species predom- 

 inates to such a degree that it colors the whole landscape. To the 

 writer this seems conclusive proof of two things, the first being 

 the comparatively recent origin of these prairies, and the second, 

 that only a small number of the prairie plants of the south can 

 withstand the climate of the Peace River region. The most 

 natural explanation of the occurrence of these prairie species there 

 is that many of the seeds were brought from the south, attached 

 to the buffalo which formerly were very abundant, and the forest 

 having been destroyed by repeated fires the conditions were more 

 suitable to prairie species than those of the forest. Those which 

 first made themselves at home soon spread and occupied large 

 areas, making it more difficult from year to year for new species to 

 establish themselves. On the other hand, the seeds of many species 

 must have beien been brought there, which if they germinated at 

 all, were unsuited to the climate and soon disappeared. But what- 

 ever hypothesis be adopted to account for the prairie in the first 

 place, or the introduction of suitable plants later on, the paucity of 

 species is very evident. Castilleia niiniata is perhaps the most 

 conspicuous and the most abundant, and not being relished by 

 cattle seriously interferes with the cutting of hay on the open prairie. 

 Several species ot leguminous plants are also common, the best of 

 these for forage purposes being Lathyrus ochrolencns, Vicia Ameri- 

 cana and Hedysaruni boreale. The latter is among the most 

 beautiful plants growing on the prairie, and to see masses cover- 

 ing many acres is a sight not soon forgotten by anyone. Though 

 not usually a conspicuous plant. Astragalus hypoglottis, is on the 

 Peace River prairies one of the most valuable forage plants, and 

 it is not uncommon to see the ground covered with this species 



