BOTANY OF LAKE HURON. 471 



Forsythia viridissima. Deutzia gracilis var. crenata, 



Cydonia japonica. Chionanthus virginica. 



Pyrus ancuparia. Rhus cotinus. 



Deutzia scabra. Liburnum odoratissimum. 



It is somewhat remarkable that the majority of all the shrubs in 

 cultivation, either in Toronto or St. Catharines, can here be brought 

 to perfection without any artificial protection whatever, but that on 

 the exposed coast-line of Lake Huron such forms cannot be openly 

 cultivated, the snow supply not being sufficient, nor its continuance 

 constant enough, to aflFord the necessary protection. 



Before leaving this portion of our subject it may not be uninter- 

 esting to indicate certain preferences among the plants of this area 

 for the Niagara and Clinton limestones, a fact which at once suggests 

 an explanation of the many anomalies in the botanical geography of 

 the district. The Ferns, Scolopendrium officinarum, Pelaea atro- 

 ■purpurea, Aspidium felixrmas, and A. lonchitis, may more especially 

 be cited as peculiar, so far as investigation goes, to the Niagara and 

 Clinton Formations of Canada. Of these, Scolop)endrium ojficinarum 

 has been reported from only two localities in North America, the 

 one at Onondaga in New York State, the other in the vicinity of 

 Owen Sound, Ontario. Pelaea atropurpurea has been detected at 

 different stations along the Niagara escarpment, from the Falls to 

 Owen Sound and Colpoy's Bay ; and Asjndium lonchitis seems to be 

 confided to the Niagara escarpment of the Bruce Peninsula. Among 

 the mosses, however, we discover a more marked predilection for 

 the Niagara and Clinton rocks of Canada. The following brief cata- 

 logue in all probability includes the principal forms under this rela- 

 tionship : — 



Anodus Dorianus. Bartramia calcarea. 



Seligera recurvata. Didymodon luridus. 



S. pusilla. D. cylindricus. 



Gymnostomum curvirostrum. Desmotodon. 



G. rupestre. Trichostomum tophaceum. 



Hypnum Sulivantii. Fissidens grandifrons. 



H. brevirostre. Dicranum Scbreberi. 



H. Somerfeltii. Eucalypta streptocarpa, 



H. clirysopliyllum, var. rupestre. Cotoscopium nigratium. 



H. compactum. Trichostomum rigidulum. 

 H. deplanatum, . ' Mnium serratum. 



Bryum albicans. Barbara fallax, 

 Leskia nervosa. 



