Claes’ specimens, stating that, with the help of the Royal 
Botanic Gardens at Kew, he had been able to determine 
yoco as Paullinia scarlatina Radlk. 
According to Radlkofer’s monographic treatment of 
the Sapindaceae, Paullinia scarlatina does not occur in 
South America and, in fact, is known only from the prov- 
inces of Izabal and Alta Verapaz in Guatemala. It there- 
fore seems quite probable that Claes’ material was wrong- 
ly determined. [tis unfortunate that this mistaken iden- 
tification has found its way into chemical literature. So 
far as L have been able to ascertain, Radlkofer does not 
cite Claes’ collections in his monograph. It is impossible 
to borrow this material for study, but I feel certain that 
it will be found to be referable to Paullinia Yoco. 
In 1931, Senor Guillermo Klug,’ a collector from Iqui- 
tos, Peru, explored the Colombian Putumayo. He made 
an extensive study and several very excellent collections 
of yoco in the Inga Indian town of Umbria. Klug’s col- 
lections of yoco, two of which are fertile, are all referable 
to Paullinia Yoco. 
Dr. José Cuatrecasas, of the Instituto de Ciencias 
Naturales, Bogota, carried out extensive botanical work, 
in the Putumayo in 1940. Among Cuatrecasas’ material 
is asterile collection of yoco from Puerto Pinuna Negra 
on the Rio Putumayo. This collection is likewise refer- 
able to Paullinia Yoco. 
It is possible that another species of Paullinia may be 
employed as yoco. In the Herbario Nacional Colombi- 
uno, there is preserved a sterile specimen from the upper 
Caqueta region (7. Perez-Arbelaez sin. num.) identified 
as Paullinia pterophylla Tr. & Planch. The collector made 
an annotation that this species represents the source of 
?T am greatly indebted to Mr. Ellsworth P. Killip of the Smithso- 
nian Institution for permission to study Klug’s specimens and_ for 
placing at my disposal Klug’s unpublished notes on yajé and yoco. 
{ 310 | 
