374 
EEYIEWS. 
was to be verified was more than could be expected. Another draw¬ 
back was the residence of his collaborator at Montpellier, at a 
distance of 500 miles from Paris, and away from any rich general 
herbarium. This entailed long correspondence and repeated delays, 
and when at length the first volume was ready for press, revolutions 
and civil wars stopped all supplies from the Government of New Gre¬ 
nada, and after years of alternate hopes and fears the completion of 
the great work originally contemplated was indefinitely postponed. 
The present Government,, has, however, so far come forward as to 
enable arrangements to be made for the publication of the first 
volume at least in an abridged form, in the Arm ales des Sciences Na- 
turelles, in detached portions, to be afterwards reissued as a separate 
work. This mode of publication, which the authors also adopted for 
the monograph of Guttiferse, has the advantage of saving from pecu¬ 
niary loss scientific labourers who can ill afford it; the chief in¬ 
convenience, independent of delay, is the impossibility of ascertaining 
the date of publication of new species in case of disputes as to 
priority, the Annales being habitually antedated, while the collected 
volumes are in a great measure post dated. 
In substance this Prodromus Florae Novo-Granatensis is not an 
abridged synopsis for the use of residents or travellers in New Gre¬ 
nada, but a critical enumeration for the use of the general botanist 
who has a library at his command, for diagnostic characters are not 
given. The names of the published species are accompanied by such 
references, ascertained synonyms, or critical observations, as the 
earnest labours of Triana, and the extensive knowledge and sound 
judgment of Planchon have enabled them to supply ; the observations 
always given in the French language. The new and imperfectly known 
species are described in Latin, the descriptions being given in the no¬ 
minative case where the species had been previously published, in the 
ablative case when new, a distinction of which we do not see the 
benefit. The ablative absolute was the form given by Linnaeus 
to his diagnoses in which he expressed within the prescribed limit of 
twelve words the most striking or best contrasted characters of each 
species. These might be sufficient so long as the species of each 
genus or section were few and comprehensive. But as the number 
of species increased, and their variability became better known, 
diagnoses professing to include all absolute characters ( i . e. all those 
without which a plant would not be conspecific) came to be more 
extended, the twelve words growing into more than as many lines, 
numerous alterations were introduced in order to admit all known 
varieties, until, in many recent works the description of all modifica¬ 
tions in number, form, or structure, conventionally taken as absolute 
or essential characters has been introduced into the ablative diagnoses, 
and the nominative description has been reserved for little more than 
dimensions, colour, etc. supposed to be accessory only. There are 
some cases, however, where, within certain limits, dimensions and 
colour have proved more constant than form or number ; accordingly 
