6\ Holmes and Batters . — A Revised List of 
to enumerate in the form of a list, available as a check-list, all 
the British species which have up to the present time been 
identified. 
There are still many species existing in our own and other 
herbaria which have not yet been examined, and which will 
probably hereafter still further enlarge the present list. In 
the form of an appendix we have given a list of species found 
on the Baltic and French coasts, which may not unreasonably 
be expected to occur on our own shores. Descriptions, or 
figures, or references to these will be found in the following 
works : — 
Bornet et Flahault, Revision des Nostocacees hetero- 
cystees. (Ann. Sc. Nat. vii serie, Bot., tom. iii. iv. v. 
and vii.) Paris, 1886-1888. 
Crouan, Florule du Finisterre. Paris, 1867. 
Hauck, Die Meeresalgen Deutschlands und Oesterreichs. 
Leipzig, 1885. 
Kjellman, The Algae of the Arctic Sea. Stockholm, 1883. 
Reinke, Algenflora der Westlichen Ostsee. Kiel, 1889. 
Stromfelt, H. G. Om Algvegetationen vid Islands Kuster. 
The authority given for the name of a species is in every 
case that of the botanist who first employed the name as it 
stands, not that of the author who first described the species 
under another name. We hold that the changes which have 
taken place in the nomenclature of a plant should be indicated 
in the list of synonyms which are usually appended to it in 
most descriptive works. The only deviation from this rule 
will be, to give in parentheses the old name under which the 
plant was described in Phycologia Britannica, or, if omitted in 
that work, in the last work on British Marine Algae in which it 
occurred. This plan will, we trust, render a reference to other 
works, and to herbaria, less toilsome. 
The mode of classification adopted has been to proceed 
from the lower to the higher forms, those being regarded as 
the lowest in which the vegetative organs are the most 
simple or least differentiated, and in which the reproduc- 
tive organs are either unknown, or belong to a low type of 
