Pleurothallis diptera Vaindley Fol. Orch. Pleurothallis 
(1859) 44, no. 279. 
Humboldtia Dinothern’ O. Kuntze Rev. Gen. Pl. 2 
(1891) 667. 
Humboldtia diptera O. Kuntze Rev. Gen. Pl. 2 (1891) 
667. 
Pleurothalls tricaudata Schlechter in Fedde Repert. 
Beith. 9 (1921) 77; ex Mansfeld in Fedde Repert. Beih. 
57 (1929) t. 115,. nr. 451, 
Judging by the type description of P. Dinotheru to- 
gether with records of that species from the Reichenbach 
Herbarium in Vienna, it would seem that the description 
of P. Dinotheru given by Lindley (1.c.) represents a dif- 
ferent concept. Lindley’s material apparently had broad- 
er sepals and a dissimilar lip. 
As represented by a photograph of the type, Plewro- 
thallis diptera differs trom P. Dinotherii in the smaller 
size of the leaves and the possibly greater length of the 
sepals. The latter organs are of precisely the same form 
in the two concepts. The lateral sepals, however, are de- 
scribed and figured as deflexed in P. Dinotheri, while in 
P. diptera some of the lateral sepals are only slightly 
decurved. In the absence of definite or striking morpho- 
logical characters, however, all attempts to separate P. 
diptera from P. Dinotherii satistactorily seem futile. 
Dr. Kriinzlin originally reterred to Pleurothallis diptera 
the collection (IWeberbauer 6827) which was later made 
by Schlechter the type of P. tricaudata. Atter examin- 
ing material of this Weberbauer number which was seen 
by both Krénzlin and Schlechter, [ am convinced that 
Kriinzlin was correct in referring the collection to P. 
diptera. Indeed, the only discrepancies between the two 
concepts Is that the flowers of the Weberbauer collection 
have a lip which is broadly cuneate, rather than subcor- 
date, below. 
