This volume contains two sections, plus addenda to Lepanthes of Ecuador, addenda to the systematics of Masdevallia, miscellaneous new combinations, and an index to all Stelis of Ecuador.
The genus Lepanthes in Jamaica:
Following a brief history of the genus Lepanthes Sw. in Jamaica, the 29 species of Lepanthes presently known to occur on that island are described and illustrated by black and white line drawings with a key to the species.
Systematics of the genus Stelis and Part IV, the conclusion of Stelis of Ecuador:
A brief history of the genus Stelis Sw., and in particular, the genus Stelis in Ecuador, is given. A new revision of the classification of the genus is presented. Species not already described and illustrated in a previous Icones Pleurothallidinarum are described and illustrated herein with a black and white drawing. A key to the species known from Ecuador is presented. Thirty-five new species are described.