118 TREES AND SHRUBS. 



petiole is prolonged into a pointed rachis, while in Serenoa it is furnished wi 

 into a rachis. From Brahia, which it closely resembles, Acoelorraphe differs c 

 thickened and does not penetrate the albumen on the side of the raphe. 



The two species of Acoelorraphe are very similar ; but until more is known about them it seems best to follow Beccari, 

 who has carefully studied the Coryphas and to whom I am indebted for much information in regard to Acoelorraphe and 

 its allied genera, and keep the two species distinct. Their distinctive characters are, — 



Petioles furnished with stout marginal teeth throughout their entire length ; leaves green on both surfaces, the pri- 

 mary divisions extending to the middle, their secondary divisions only from 8 to 15 centimetres long ; flowers from 

 2 to 2.5 millimetres long ; fruit from 8 to 9 millimetres in diameter ; stems forming large thickets. 



1. A. Wbightii. 

 Petioles furnished with thinner teeth, usually unarmed toward the apex ; leaves green or glaucescent on the lower 

 surface, their primary divisions extending nearly to the base, the secondary divisions often 25 centimetres long ; 

 flowers not more than 2 millimetres long ; fruit from to 7 millimetres in diameter. 2. A. Arbokescens. 



The synonomy of the second species becomes, — 

 Acoelobbaphe AEborescens (Sargent), Beccari, Webbia, ii. 113 (1907). 



Serenoa arboreseens (Sargent), Bot. Gazette, xxvii. 90 (1.899) ; Silva N. Am. xiv. 77, t. 734 ; Man. Ill, f. 98.— 



Small, Fl. Southeastern U. S. 224. 

 Paurotis Wrightii, Britton & Shafer, N. Am. Trees, 141 (in part) (1908). 



An additional station for Acoelorraphe arboreseens is at the head of East River, White Water Hay, where it was col- 

 lected by A. A. Eaton on March 22, 1905, and by J. B. Ellis in June and October, 1908 (in herb. Arnold Arboretum). 



C. S. S. 



