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a few very interesting species occur which are not known on the 
mainland; the oe columnar cactus Lemaireocereus hystrix is 
abundant, and very luxuriant; a small yellow-flowered Portulaca 
with globular ee interested us exceedingly. The density of 
the vegetation an ifficult walking prevented our making a 
complete investigation in the time at our command; more 
Britton, with Professor ae Mrs. Wille, had arrived at Ponce ie 
the courtesy of Senor Bartolome Barcelo o juntas, nuts and 
foliage of the Porto Rico walnut, now a very rare tree, and, at 
Hatillo, living plants and specimens of one of the water-lilies, 
from a small pond in which the plant was beautifully in flower. 
On March 13 the whole party went by motor-car to study the 
primaeval mountain forest at Arroyo de los Corchos on the road 
J 
r. Brown and Dr. Britton at the junction of the Jayuya road 
the summit of Monte Cerrote was re: an considerable 
a f primaeval forest was traversed, which yielded another 
large collection of mountain forest speci r ell collected 
east of Ponce. March 17 was given to a visit by motor-car to 
