The floral analysis of Odontoglossum Loesenerianum 
indicates that this concept is surely referable to O. an- 
gustatum as first described by Lindley, the only apparent 
discrepancies being that the bracts are noted as being 
equal to or a little exceeding the ovary (they are about 
half as long in O. angustatum) and the flowers are de- 
scribed as somewhat smaller. This difference in size is 
probably due to an immature condition. 
In the several collections here referred to O. angusta- 
tum, there appears to be a wide variation both in vege- 
tative and floral size and in the form of the lip. The most 
striking variations from the usual form are seen in Var- 
gas 2888, where the obviously immature flowers are 
smaller than those of O. Loesenerianum and have a lip 
which is more or less lightly pandurate; and in Weber- 
bauer 7797, where the carinate calli at the base of the 
lip are broader, blunter and thicker than in the usual 
form. All of the Peruvian collections included in this 
species, however, have a general similarity of lip calli, 
but there is apparently lacking from all of them one extra 
pair of tubercles present in the type. 
It seems to me, therefore, that Odontoglossum angus- 
tatum is a conspicuous example of the polymorphism 
that makes the tropical orchids so difficult. 
Odontoglossum aureo-purpureum (as auropur- 
pureum) Reichenbach filius in Linnaea 22 (1849) 848; 
Lindley Fol. Orch. Odontoglossum (1852) 15, no. 44. 
Odontoglossum compactum Reichenbach filius in Gard. 
Chron. n.s. 3 (1875) 492. 
Odontoglossum Koehleri Schlechter in Fedde Repert. 
Beih. 9 (1921) 109; ex Mansfeld in Fedde Repert. 
Beih. 57 (1929) t. 128, nr. 501. 
The concept Odontoglossum compactum is based in part 
on Peruvian specimens collected by W. Lobb which 
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