FLO 11A OF NEW GRENADA. 
375 
even those are now admitted into the ablative diagnoses, which, in 
Triana and Planch on’s Flora for instance, only differ in general from 
descriptions in their inconvenient phraseology. It would be a great 
improvement in our modern systematic works, whether Floras or 
Monographs, if the Linnean restrictions on diagnoses were again en¬ 
forced, including in them only the most striking, essential, or con¬ 
trasted characters, under the distinct understanding that they are to 
serve as a guide only to the reader, who would then rely upon the 
detailed description in a more manageable nominative form, in broken 
sentences, for the absolute identification of his species. 
At the conclusion of each natural Order a few lines are very use¬ 
fully devoted to a sketch of the geographical relations of its New- 
Grenadine representatives, and the synonymy and critical observa¬ 
tions are, as might be expected from so sound a botanist as Dr. 
Planchon, generally to be depended on so far as they go. But in 
this respect, as well as in specific affinities, completeness as to what 
is already known, and even in some cases accuracy, can only be at¬ 
tained by treating each species or group in succession monographi- 
eally. It is for this reason that, with equal merits of authorship, 
the observations of the monographist always inspire greater confi¬ 
dence, and are therefore much more important than the passing cri¬ 
ticisms of the enumerator of the plants of a collection, or of a 
district. The need of such a comprehensive research became parti¬ 
cularly apparent to our authors when they came to Guttiferse, of 
which they had much that was new to deal with. This Order is much 
more abundant within the tropics, than the comparatively scanty 
specimens we possess would lead us to suppose. The rigid succu¬ 
lent or gummy leaves, flowers, and fruit, are not tempting to ordinary 
collectors, who seek for showy plants, easily preserved. The speci¬ 
mens are, moreover, very apt to fall to pieces when dry, the flowers 
are often few and mostly dioecious, and thus complete and well-matched 
specimens of some of the commonest kinds are rare in herbaria. 
Guttiferse had thus been generally neglected, or, with few excep¬ 
tions, ill-defined and badly grouped. The new forms supplied by the 
New Grenada collections could not be determined without a revision 
of the genera next to which they should be placed, and Dr. Planchon’s 
sagacity soon discovered the necessity of remodelling the whole system 
of their classification. In attempting this he found so much that was 
new and interesting in the varieties of floral structure and symmetry 
in species otherwise too closely allied to be generically separated, that 
he and his collaborator were induced to proceed to a detailed 
examination of every species of which they could procure specimens, 
and thus it was that the excellent and elaborate monographic memoir 
grew out of the enumeration they were preparing. And no work 
illustrates better the impossibility of determining a priori , whether a 
character first observed in a newly-discovered species is or not a good 
generic distinction. Their first impulse in determining M. Triana’s 
novelties was to propose a number of new monotypic genera. In 
