Recent Progress and present State af Systematic Botany. 851 
tion, which are but different names for the same thing, an 
which it appears to me would be always more satisfactory in 
the nominative than in the ablative case. ter the example 
of Linngeus, and based upon the doctrine of the fixity of species, 
it has been almost universally the custom to distinguish the 
specific diagnosis and description, the former to contain the 
absolutely distinctive characters (any deviation from which 
would exclude a plant from the species), the latter to aid the 
student in identifying a plant by the enumeration of characters 
Ageie “eee Sgrepen might vary in the same species, or which 
may pos in common with other sae In order to 
eve 
Hea To which may not peo aay admit of exceptionss 
and although care should be taken to select the most important 
and constant ones, yet in some instances, those which are 
generally discarded as too variable for a diagnosis, such as 
dimensions, colour, &c., may yet be most useful, or even essen- 
tial for the distinition of species, or even of genera. These 
diagnoses, moreover, to be useful should be short. We cannot 
now restrict them to the twelve- word law of Linnaeus, but a 
ce. 
er synonymy 
should be avoided, ea where it may be necessary to refer to 
only when te may assist ess ntially i in the ee aoe deter- 
mination and elucidation of a asi All discussions on doubt- 
points and all details should d be reserved for monographs or 
Separate papers, where alone they can really tend to the advance- 
ment of the science. 
“Kach volume of the ‘Synopsis’ would of course be accom- 
panied by a full index oh genera, species, a ay such synonyms 
as it may have been found necessary to gi 
“The whole work would be so ‘pals feces sable to botanists of 
all nations, that, like the ‘Genera Plantarum,’ it should be en- 
tirely in bota nical Latin, which, moreover, from the number of 
Henin expressions to which a technical meaning has been 
assigned, is specially suited for short diagnoses. 
