58 THE ROYAL SOCIETY OF CANADA 



assistance, moie paitifularly in the indentification of species, of Dr. A. 

 H. Mackay, of Halifax, and Mr. Oliver Kendall, Jr., of Providence, R.I., 

 both special and successful students of Diatoms. The literature 

 available on the writer's part for the work embraces all the early writings 

 of Prof. J. W. Bailey, of West Point, N.Y., the earliest student of 

 Diatoms in America; Smith's British Diatoms; Van Heurck's Diatoms 

 of Belgium; Wolle's Diatoms of North America; Gran's Nordisches 

 Plankton; Schmidt's Atlas der Diatomaceen-Kunde; the "Diatomiste," 

 the Journals of the Microscopical Society of London and Pritchard's 

 Infusoria, besides somewhat numerous papers by Mann, Cleve. Walker- 

 Arnott, Cîreville, Gregory, Edwards, Lewis and others. He has also 

 had the advantage of possessing many slides, drawings and descriptions 

 prepared by the late Prof. J. W. Bailey, representing in many cases 

 the original types from which a large number of forms, first named and 

 described by him or by Ehrenberg, were derived. 



As Diatoms, like other plants, are directly affected by their environ- 

 ment, it is proposed in this paper first to give some account of the 

 physical conditions which characterize the region from which the col- 

 lections were made, and secondly to give a classified list of the forms 

 so far observed, with critical notes upon the latter. 



It would seem at first that a natural division might be made between 

 fresh water and salt water forms. But practically this is impossible. 

 For while of course typically marine genera, such as Coscinodiscus, 

 Triceratium, Biddulphia, &c., are not to be found in fresh-water lakes and 

 ponds, they are nevertheless found in the rivers many miles from the 

 sea, while on the other hand, such forms as Navicula viridis, Stauroneis 

 phœnicenteron, Cocconeis Placentula, Epithemia turgida, Nitschia 

 sigmoidea, Synedra ulna and many others, ordinarily regarded as fresh- 

 water forms, not only occur in the brackish waters of estuaries, but also 

 in purely salt waters at many points along the coast. The late Rev. 

 William Smith, in his classical work on the British Diatomaccœ, says 

 that these "inhabit the sea or fresh water, but the species peculiar to 

 the one are never found in the living state in the other locality, though 

 there are some which prefer a medium of a mixed nature, and are only 

 to be met with in water more or less brackish"; but these views are 

 cetainly not in accordance with the facts as observed in New Brunswick, 

 as they have also been shown to be incorrect in other parts of America. 

 The late Prof. Bailey, of West Point, found marine Diatoms in Lake 

 Monroe, Florida, two hundred miles from the sea and on the Hudson 

 at a distance of nearly one hundred miles, while in New Brunswick the 

 writer has found such forms as Doryphora Boeckii, Triceratium alternans 

 Grammatophora marina and Coscinodiscus eccentricus at points from 

 ten to fifteen miles above the mouth of the St. John river. Navicula 



