TABLE OF CONTENTS 
NUMBER | (Jan. 31, 1978) 
Studies in American Orchids X 
DW IESE A CIABAY cc sertivenideaeeanitenpsanuvecsaisvscess l 
Revision of the Genus Masdevallia - | 
by HERMAN R. SWEET. ...........cccccceececceceeccececeeaeens 39 
Studies in the genus Oncidium - II. Section Serpentia 
Oy OPIN, Foe ERO ies cee oeinccy eastern reaececues nausea cceess 55 
NUMBERS 2 - 4 (Feb.-April 1978) 
Bibliography of Precambrian Paleontology 
and Paleobiology 
by STANLEY M. AWRAMIK AND 
EO PUN RGOORS eeu viviseensod ceieeednceses elas eenaaias 65 
NUMBER 5 (May 30, 1978) 
De Plantis Toxicariis e Mundo Novo Tropicale Commen- 
tationes XXIII. Notes on Biodynamic Plants of 
Aboriginal Use in the Northwestern Amazonia 
by RICHARD EVANS SCHULTES  ......cc.cceeceeeeeeeeeeeeeees ye 
Cocaine in Blood of Coca Chewers 
by B. HOLMSTEDT, J.-E. LINDGREN, L. RIVIER AND 
Be IAN acoso thse g senna ran trsesteaataueeeteiserai os 199 
Chromosome Numbers in Neotropical Erythroxylum 
(Erythroxylaceae) 
by T. PLOWMAN, L. RUDENBERG 
PI Ss WIRE EG du dirrenciutaeuusarersaatenierseebarniccediawe: 203 
NUMBER 6 (June 30, 1978) 
Soma Brought Up-to-date 
by R. GORDON WASSON  .........ccc cece ceceeceesceeseeeeeeeees 211 
De Plantis Toxicariis e Mundo Novo Tropicale 
Commentationes XXIII 
DY RICHARD EVANS SCHULTES: ccccscessekicsiscaivaviveuace 225 
