6 TRANSACTIONS OF THE [OCT. 7, 



nity to express my belief in the accuracy of his conclusions, 

 based on the same characters as those assigned in the original 

 description. 



In the Pocono localities the plant grew actually in the water, 

 in cold mountain springs and brooks, and densely shaded by 

 overhanging bushes. The very different habit of the C. pahtstris, 

 growing in open, sunny swamps, is a fact which does not appear 

 to have yet been recorded. 



Mr. Maturin L. Delafield, Jr., has communicated tome speci- 

 mens of a CaUha from West Hampton, Suffolk County, N. Y., 

 which I refer without hesitation to this mountain species. Mr. 

 Delafield has not detected the typical C. jyalustris in the region; 

 and knowing what we now do of the numerous elements in com- 

 mon possessed by the floras of the Shawangunk and Pocono 

 Mountains with those of the coast plains, this is not as remark- 

 able as it might at first appear.' 



If it should seem desirable in the future to reunite it with the 

 Old World plant which has been known as C. palustris, L., 

 var. Sibirica, Kegel (1861), it is to be remembered that this 

 name is long antedated by (7. radicans, Forster, Trans. Linn. 

 Soc. viii. 324, t. 17 (1805). But it does not appear to me from 

 the materials now at hand that this will again be suggested. 

 Dr. Gunther Beck, in his review of the relatives of C. pahtstris, 

 in Verhand. K. K. Zool.-Bot. Ver. Wien, xxxvi. 350 (lb86), 

 excludes C. flabellifolia. In Torrey and Gray's Flora the name 

 is stated to be synonymous with C. dentata, of Muhlenberg's 

 Catalogue (1813), but the description there given is not suf- 

 ficiently explicit, and until the fact can be more conclu- 

 sively shown I do not consider it safe to take up Muhlenberg's 

 name. 



Castalia tetragona (Georgi), Lawson, Trans. Eoy. Soc. 



Canada, vi. sec. iv. 112 (1888). 

 Nymjihcea tetragona, Georgi, Reise im Russ. Reichs, i. 220 



(1775). 

 Castalia pygmcea, Salisb. Parad. Lond. t. 68 (1806). 

 JVgmphcBa pygmma. Ait. Hort. Kew. ed. 2, iii. 293 (1811). 



This may be announced as a North American plant, having 

 been collected in ponds along the Severn River, Keewatin, 

 Canada, by Mr. Jas. M. Macoun, July 17th, 1886. This local- 

 ity lies between Hudson's Bay and Lake Winnipeg, in latitude 

 about 55°. It had previously been collected by Mr. R. Bell at 

 Misinaibi River, Ontario (July, 1879). Specimens from both 

 localities are preserved in the herbarium of the Geological and 

 Natural History Survey of Canada. The pl ant may at once be 



' Bull. Terr. Bot. Club, xi. 136-128; xiv. 187-189. 



