late leaves, but in a few cases the petiole is very short. 
It is almost invariably articulate with a number of sharp 
or blunt teeth at the joint, this articulation usually being 
some distance above the base of the leaf, and sometimes 
in the centre of the long slender petiole. Reichenbach 
and Schlechter, when dealing with some species, have 
treated the lower part of the petiole below the articula- 
tion as being the rostrate upper internode or prolonga- 
tion of the pseudobulb, but this is clearly not a possible 
interpretation in plants like J”. sawndersiana where there 
are two leaves, both with their petioles articulate some 
distance above the base. The leaves are usually rather cori- 
aceous and often banded or spotted with paler markings. 
‘* As these variable characters are associated with very 
similar floral structures I feel that too much emphasis 
should not be placed on them and that all these species 
should be placed in an enlarged Hulophidium.” 
In no way diminishing the value of these important 
observations, we are compelled to reexamine some of its 
crucial points. We believe that the distinction between 
homoblastic and heteroblastic pseudobulbs is not clearly 
understood by many. Both types of pseudobulbs are de- 
rived from the common sympodial stem which consists 
of aset of nodes and internodes. In the case of the homo- 
blastic pseudobulbs, each internode or most of the inter- 
nodes are equally developed and enlarged throughout 
the entire length of the sympodium, at the nodes leaves 
or sheaths or cataphylls are produced. In the case of the 
heteroblastic pseudobulbs only one internode is fully de- 
veloped and enlarged throughout the entire length of the 
sympodium. The nodes are closely approximate, often 
so congested that no visible separation is apparent ; rarely 
the leaf-bearing nodes are separated by obvious distances, 
yet minimal in proportion to the internode that repre- 
sent the true heteroblastic pseudobulb. The one to three 
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