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spent two months of the spring of 1906 engaged in botanical 

 study in the island of Jamaica. Most of the time was spent at 

 Cinchona, the Tropical Station of the New York Botanical Garden. 

 Here we joined Dr. Forrest Shreve, who was spending the year of 

 his tenure of the Bruce Fellowship of this University in a study 

 of the forest of the Blue Mountains of Jamaica. 



While on the island, the writer was engaged in studying and 

 collecting developmental material of the native species of Pip- 

 eraceae and Chloranthaceae. A former visit in 1903 showed 

 Jamaica to be a very favourable place for the study of these 

 groups of plants. Some of the species obtained in 1903, which 

 proved most interesting, were forms of which but little material 

 was found, or of which, because of the shortness of the stay, but 

 few developmental stages were secured. 



During this second trip more complete material of the species 

 found in 1903 was obtained and a considerable number of new 

 forms were collected. Altogether material is now at hand for 

 the study of the seed development of twenty Jamaican species of 

 Peperomia and twelve species of Piper. 



A considerable number of species of Peperomia occur in the 

 lowlands of Jamaica, but they are more abundant in the highlands, 

 especially in the Blue Mountains. Here they occupy a great 

 variety of habitats, and show modifications in structure which 

 are often clearly adaptive to the peculiarities of the habitat. 



Along the trails at from 1,200 to 1, 800 meters elevation, on the 

 dryer southside of the Blue Mountains, several strongly xerophytic 

 species of Peperomia occur. Among these are P. reflcxa, P. quadri- 

 folia, and P. verticillata. Higher up on exposed limestone cliffs P. 

 galioides is found. In the wooded areas, between the altitudes 

 mentioned above, several slightly less xerophytic species occur 

 on the soil of ridges or hillsides, on shaded rocks, or as epiphytes. 

 Among these are P. acuminata, P. distachya, P. glabella, P. maculosa, 

 P. magnoliaefolia, P. rlwmbca, P. stellata, and P. septemnervis. 



In the dense forests P. tenclla and P. filiformis occur as epi- 

 phytes, while the very delicate P. hispidula is found among mosses 

 on the saturated humus of the forest floor in deep ravines. 



The extremes of adaptive structure that may occur in this single 

 genus can best be indicated by comparing a xerophytic species 

 such as verticillata with a hydrophytic one such as hispidula. 

 P. verticillata is a hairy species 1 5-25 centimeters high, with 

 an erect, fleshy stem. The obovate leaves are 1 5-20 millimeters 

 long, 10 millimeters wide, and many of them are swollen to a nearly 

 hemispherical form with a massive water storage tissue. The 

 leaves as well as the stem are covered by a dense layer of thick- 

 walled, several-celled hairs, which seem capable of aiding the 

 thick cuticle in reducing transpiration to a minimum. 



Not only in the structure of the vegetative parts, but also in that 

 of the inflorescence, this plant is strikingly fitted for a dry habitat 

 The axis of the spike is fleshy and the ovaries and stamens, when 

 young and delicate, are sunk in depressions of the axis and pro- 

 tected without by the circular tops of the long-stalked, overlapping 



