COROCORO COPPER DISTRICT OF BOLIVIA 101 



mediumly stout, generally curved, not especially prominent. 

 Secondaries thin but prominent, numerous; about 10 

 opposite to alternate pairs diverge from the midrib at 

 angles averaging about 45 and are camptodrome. Ter- 

 tiaries thin but well marked. 



This is a common and characteristic form in the Coro- 

 coro and Potosi collections, much like numerous previously 

 described fossil species and many still existing species of 

 this large genus, especially the existing Cassia ligustrina 

 Linnaeus after which it was named. Britton has referred 

 several forms to this species which fall beyond its limits of 

 variation, and this is especially true of the small petiolate 

 leaves shown in his figures 26 and 27. Engelhardt's name 

 is preoccupied by Schrank, 1816. Cassia chrysocarpoides 

 Engelhardt is much shorter and wider, Cassia cristoides 

 Engelhardt is a much smaller spatulate form, Cassia 

 wendtii Britton is very much smaller and oblong elliptical 

 in form, Cassia singezvaldi Berry is a broadly elliptical 

 form. Cassia rigidulifolia Engelhardt is a large retuse 

 form, Cassia obscura Engelhardt is a very small obscure 

 form, and Cassia incmbranacea is very similar to the pre- 

 sent species, but with slightly wider thinner leaflets with 

 more numerous secondaries. 



>>>'**' " 



Genus Copaifera LINNE 

 Copaifera corocoriana BJ?,RRY^ 



PLATE VII Fig. 8. 



Copaifera corocoriana Berry, Proc. U. S. Natl. Mus., vol. 54, p. 

 144, pi. 16, fig. 18, 1917. 



Description. Pod of small size, nearly orbicular in out- 

 line, greatly compressed, pedunculate, obliquely cuspidate 

 tipped, single seeded. Length, about I cm. from the top 

 of the recurved cuspidate tip to the top of the peduncle. 

 Horizontal diameter, about 8 mm. Peduncle stout, about 

 4 mm. long: Seed lenticular, nearly orbicular, compressed, 



