NEOARBOTTIA, A NEW CACTl^S CxENUS FROM 

 HISPANIOLA 



By N. L. BRITTON and J. N. ROSE 

 (With Four Plates) 



Among the earliest cacti described were those obtained by Plumier, 

 more than two hundred years ago, mostly from the island of His- 

 paniola, better known as Santo Domingo. These were characterized 

 briefly by him in 1704 and his illustrations of them were published 

 in 1755 by Burmann ; Lamarck gave most of them binary names in 

 1783 under the genus Cactus, and in 1828 De Candolle referred all 

 the cereoid forms to the genus Cereus; the other species described 

 by Plumier have been referred by various authors to Mammillaria, 

 Cephalocereus, Pilocereiis, Rhipsalis, Melocactus, Pereskia, Opuntia 

 and Nopalea. We have experienced great difficulty in definitely 

 identifying the plants from the illustrations of Plumier, since these 

 are largely diagrammatic. As the type locality is generally given, 

 however, the identification of all of them may eventually be made 

 fairly definite. 



In 1920 when Dr. W. L. Abbott and Mr. E. C. Leonard were start- 

 ing for Haiti, we asked them to collect both living and herbarium 

 specimens of all the cacti met with. As good fortune directed, they 

 spent a considerable time on the Cul-de-sac, where Plumier collected, 

 and so probably obtained several of the species which he described. 

 About 20 species of cacti were observed by them there. One of 

 these, which has proved to be an undescribed genus, is the subject 

 of this article. The Cul-de-sac is the bottom of an old salt lagoon, 

 which now has an altitude of 20 feet or more above the sea. It is 

 a coral formation and an ideal habitat for many kinds of cacti. Here 

 they appear in thickets or literally as forests, forming the dominant 

 feature of the landscape. This region lies north and east of Port- 

 au-Prince, extending from the bay of Port-au-Prince to Lake 

 Saumatre. 



After the return of Dr. Abbott and Mr. Leonard in September 



of the same year with these valuable specimens we wrote, at the 



suggestion of Mr. Leonard, to Mr. H. M. Pilkington, an American 



business man then stationed at Port-au-Prince, asking him to pro- 



Smithsonian Miscellaneous Collections, Vol 72, No. 9 



