different from those envisioned by Holttum. He recog- 
nizes two subtribes, Angraecinae with a deeply excised 
or cleft clinandrium and an abbreviated rostellum, and 
A érangidinae with an entire clinandrium and a promi- 
nent rostellum. 
Evaluation of Generic Criteria 
Disturbed as well as intrigued by the available infor- 
mation, especially the misrepresentation and incon- 
sistentcy of them, several years ago I initiated a study 
toward the delimitation of the genera in the monopodial 
orchids with the intention of presenting a key to them. 
In order to secure the correct interpretation of criteria 
for each genus, it became necessary to typify every ge- 
neric name as astarting point. With 186 currently recog- 
nized genera and approximately 2150 species assigned to 
them, the task appears to be an endless chore with the 
end not yet in sight. Having studied literally hundreds 
of type specimens, the length of the list of incorrectly 
placed taxa has already outgrown the average length of 
papers normally printed in periodicals. Consequently 
this study has to be published in parts, the first of which 
deals only with those genera where nomenclatorial 
changes are necessary. Such genera are typified and 
their salient features are given. Emphasis is placed on 
the floral structures, since the vegetative aspects are 
characteristic for the entire phyletic line. The position 
and size of the column including its parts and accessory 
organs, such as the various wings, arms, foot-like ex- 
tensions, clinandrium, rostellum and stigma, present a 
large series of patterns. The number of pollinia, exclud- 
ing the semantical interpretation of two in four or four 
in two, is definitely a weighty character. The insertion 
of the petals and the lateral sepals is likewise an impor- 
tant criterion. In many instances, of course, the clearest 
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