‘Tan. 8374. 
ONCIDIUM SanpDERAE. 
Peru. 
ORCHIDACEAE. Tribe VANDEAE. 
Oncrpium, Swartz; Benth. et Hook. f. Gen. Plant. vol. iii. p. 562. 
Oncidium Sanderae, folfe in Gard. Chron. 1910, vol. xlviii. p. 67; Orch. Rev. 
1910, pp. 248, 351; affinis O. Papilioni, Lindl., sed petalis Jabelloque 
magnopere crispo-undulatis et columnae alis glanduloso-pectinatis differt. 
Herba; epiphytica. Pseudobulbi ovato-oblongi, subcompressi, 4-6 cm. longi, 
3-4 cm. lati, monophylli. lia subsessilia, corincea, oblonga, subobtusa, 
brunneo-reticulata, 20-45 em. longa, 5-8 cm. lata. Scapi suberecti vel 
arcuati, circiter 80 em. longi, prope apicem subcompressi, pauciflori ; 
bracteae oblongo-lanceolatae, acuminatae, 2 em. longae; pedicelli 4-5 cm. 
longi. Flores speciosi, heterochronici. Sepa/um posticum lineari-lanceo- 
latum vel subspathulatum, acutum, circiter 8 em. longum, rufo-brunneum ; 
sepala lateralia oblonga, acuta, crispo-undulata, flava, bruanneo-maculata, 
6-7 cm. longa, 2 em. lata. Peta/a lineari-lanceola'a vel subspathulata, 
acuta, rnfo-brunnea, circiter 7 em. louga. Labe//um trilobum; lobi laterales 
rotundati, crispo undulati, flavi, brunneo-maculati, 1 em. lati; lobus inter- 
medius unguiculatus, orbicularis, crispo-undulatus, circiter 3-5 em. longus 
et latus; crista 5-loba, laevis. Colmna 1 cm. longa, clava‘a, alis latis 
longe glanduloso-pectinatis.—R. A. Rours. 
The remarkble Oncidium which torms the subject of our 
plate is a very interesting addition to the small group of 
species known as Butterfly Orchids hitherto believed to 
consist of but two species, viz. :—O. Papilio, Lindl., figured 
at t.2795 of this work, which isa native of Trinidad and the 
adjacent coast of Venezuela, and O. Kramerianum, Reich. f., 
which occurs in Colombia and Ecuador. This new member 
of the section is a native of Peru, where it was obtained in 
the Moyobamba district by Mr. Forget, when collecting 
on behalf of Messrs. F. Sander & Sons, by whom it was 
imported in 1909. It flowered in the firm’s nursery at 
St. Albans in August, 1910, and from their plant was 
received the material on which our figure is based. The 
three species of which this group is composed bear a close 
resemblance to each other in habit and in the handsome 
marbling of their leaves. It is interesting to note that 
although geographically more remote from O. Papilio than 
from VO. Kramerianum, it is to O. Papilio that O. Sanderae 
is most close] y allied, the upper portion of the inflorescence 
May, 1911. 
