257 



upon some of the general characteristics of the non-articulated 

 corallines, and showed microtome sections and photomicrographs 

 illustrating the structure of the two species that were under dis- 

 cussion. In reply to a question as to the ecological relationships 

 of the coralline algae and the true corals, it was stated that though 

 certain species of both groups are reef-builders and inhabit sim- 

 ilar places, each of the groups seems to be somewhat inimical to 

 the other. A place in which corals are flourishing is not a good 

 place in which to look for coralline algae, and vice versa. It is 

 a common thing to find corallines attached to dead or moribund 

 corals, but comparatively rare to find the corals growing on cal- 

 careous algae. In one case a crustaceous coralline was noticed 

 to be encroaching upon and covering a living coral. 



"Remarks on the Flora of Nova Scotia," by Dr. C. B. Rob- 

 inson. 



The province of Nova Scotia consists of a peninsula connected 

 with New Brunswick by an isthmus of very slight elevation, and 

 the island of Cape Breton separated from the rest of the province 

 by the Strait of Canso, which at the narrowest place is less 

 than a mile broad. The northern part of the island is composed 

 of hills between 800 and 1,400 feet high, except narrow strips 

 along the coast and in the river valleys. 



In general, the flora of the peninsula and island is composed 

 of plants which have migrated from the west or southwest 

 through New Brunswick, many species having their northeastern 

 limit in the province. A second source lies in the introduction 

 chieflly from Europe, of weeds in ballast, etc., and many species 

 thus added to the flora are very conspicuous and troublesome. 

 But the main purpose of the paper was to call attention to the 

 presence in northern Cape Breton of a third element, namely, 

 species that are believed not to occur anywhere upon the penin- 

 sular portion of the province, and in some cases not in New 

 Brunswick. Such cases are always open to the suspicion of in- 

 complete collection, but this can hardly be held to explain the gap 

 in the distribution of the male fern, Dryoptcris Filix-mas (L.) 

 Schott, known from about twenty localities in this region, 

 although nowhere abundant there, and not found otherwise east 



