2 Britton: Studies of West Indian Plants 



long, maturing 2 achenes; lower empty scales broadly ovate, the 

 others lanceolate, acuminate; bristles none; achenes obovate- 

 orbicular, I mm. long, pale brown, shining, finely cancellate; 

 tubercle triangular-lanceolate, acuminate, flat, about one-third 

 longer than the achene, its base nearly truncate. 



Rocky banks in the Blue Mountains of Jamaica; type, from 

 Hardware Gap, N. L. Britton 3322, collected Sept. 9, 1908. Re- 

 lated to R. elongata (Boeckl.) Clarke, and to R. polyphylla Vahl, 

 but at once distinguished from them by its pubescent sheaths. 



I. P. circinale. 



2. P. Unguis-cati. 



3. P. guadalupense. 



4. P. bahamense. 



5. P. Hystrix. 



24. THE GENUS PITHECOLOBIUM IN CUBA 



A. Pods curved or coiled, dehiscent, the valves twisting after separating. 



1. Seeds with a fleshy aril; stipules spinescent; pinnae i 



or 2 pairs; leaflets 2-4 pairs. 

 Leaflets 1-6 cm. long (species perhaps confluent). 

 Leaflets spinulose-mucronate. 

 Leaflets obtuse or mucronulate. 



Leaflets chartaceous; petioles of the lower 



leaves, at least, longer than the petiolules. 

 Leaflets coriaceous; petioles shorter than the 

 petiolules or as long. 

 Petioles and petiolules stout; leaflets large, 



2.5-6 cm. long. 

 Petioles and petiolules slender; leaflets small, 

 1-3 cm. long. 

 Leaflets only 3-7 mm. long. 



2. Seeds without a fleshy aril; stipules not spinescent; 



pinnae 2 pairs or more; leaflets 3 pairs or more. 

 1. Leaflets obovate to oval, large, 1.5-6 cm. long, 3-6 

 pairs to each pinna. 

 Calyx subtruncate at base; seeds oblong, about 



twice as long as wide. 

 Calyx narrowed at base; seeds suborbicular to 

 obovate. 

 Pinnae 3 or 4 pairs; leaflets 4-6 pairs; calyx 



narrowly campanulate, thin. 

 Pinnae 1 or 2 pairs; leaflets 2-4 pairs; calyx 

 broadly campanulate, coriaceous. 

 Calyx truncate, its teeth minute, mucronu- 

 late. 

 Calyx teeth large, broadly ovate. 



Calyx short-campanulate; stamen- tube 



short; leaflets broadly obovate. 

 Calyx long-campanulate; stamen-tube 

 5-6 mm. long; leaflets oblong to obo- 

 vate. 



6. P. savannarum- 



7. P. discolor. 



8. P. Iruncatam, 



9. P. obovale. 



10. P. pinetorum. 



