234 PROCEEDINGS OF THE AMERICAN ACADEMY. 



Phycotheca Boreali-Americana, issued by Collins, Holden and Setchell, 

 and Phykotheka Universalis, issued by Hauck and Richter : references 

 to these are given under the respective species, with the abbreviations 

 P. B.-A. and P. U., and the numbers. 



The Humphrey collection includes 25 fresh water algae, the Pease and 

 Butler collection 9 ; only two species are common to both. If we com- 

 pare the marine species * in these two collections, we find that of the 

 whole number, 215, only 72 occur in both; 143 are found in one and 

 not in the other. A natural inference from this would be that the field 

 was by no means exhausted, and that more species might be expected. 



In Murray's list four species are given, which are omitted here : 

 Gymnogongrus furcellatus, Phyllophora Brodiaei, Liagora viscida, and 

 Plocamium coccineum, the first on the authority of Wright, the others of 

 Chitty. Probably a misplacement of labels has occurred. 



Tables have been prepared, comparing the marine flora of Jamaica 

 with the floras of New England, Great Britain, the northern coast of 

 Spain, the coast of Morocco, the Canary Islands, and Puerto Rico, lists 

 having been published of these regions of sufficient extent to make a 

 comparison of interest.f 



Some of these regions having been more thoroughly explored than 

 others, too much importance should not be given to the total number of 

 species in any region ; the relative proportion of the different classes is 

 of more weight, while the number of species common to two regions 



* In making up tliese statistics, named varieties and forms have been counted 

 the same as species. 



t Tlie data of tiiese tables are from the following works : — 



Preliminary List of New England Marine Algae, by F. S. Collins, Ehodora, Vol. 

 II. p. 41, 1000. 



A Revised List of the British Marine Algae, by E. M. Holmes andE. A. L. Bat- 

 ters, Annals of Botany, Vol. V. p. 63, 1892. 



Note Preliminaire sur les Algues Marines du Golfe de Gascogne, par C. Sauva- 

 geau, Journal de Botanique, Vol. XL, 1897. 



Les Algues de P.-K.-A. Schousboe, par E. Bornet, Memoires de la Societe' Na- 

 tionale des Sciences Naturelles de Cherbourg, Vol. XXVIII. p. 165, 1892. 



Plantes Cellulaires des lies Canaries, par C Montagne, Paris, 1840. 



Crociera del Corsaro alle Isole Madera e Canarie ; Alghe, per Antonio Piccone, 

 Genova, 1884. 



Contributions a la Flore Algologique des Canaries, par Mile. A. Vickers, An- 

 nales des Sciences Naturelles, Series 8, Botany, Vol. IV., 1897. 



Meeresalgen von Puerto-Rico, von F. Hauck, Eugler's Botanische Jahrbiicher, 

 Vol. IX. p. 30, 1888. 



In addition to the published lists of the Canary Islands, some species have been 

 included from the collection of the author. 



