98 STUDIES IN GEOLOGY, No. i 



the subandean zone of the eastern slopes, but so far as I 

 know none occur in or west of the Cordillera Real or 

 eastern Andes. 



Genus Enterolobium MARTIUS 

 Enterolobium grandi folium ENGEXHARDT 



PLATE VII Fig. 16. 



Enterolobium grandifoUum Engelhardt, Sitz. Naturvv. Gesell. Isis 

 in Dresden, 1894, Abh. i, p. 12, pi. i, fig. 60. 

 Berry, Proc. U. S. Natl. Mus., vol. 54, p. 135, pi. 15, fig. 30, 1917. 



Description. Leaflets sessile, falcate-lanceolate in out- 

 line, with a shortly acuminate, cuspidate, inequilateral tip 

 and a bluntly pointed very inequilateral base. Margins entire 

 Texture subcoriaceous. Length about 1.6 cm. Maximum 

 width, midway between the apex and the base, about 4 mm., 

 one-fourth on one side of the midrib and three-fourths 

 on the opposite side. Midrib mediumly stout, curved. 

 Secondaries mostly obsolete by immersion, a few sub- 

 parallel with the lower lateral margins and camptodrome 

 are made out With difficulty throughout most of the leaflet ; 

 the basal and second secondary on the enlarged side of the 

 leaflet are more prominent and the latter curves upward 

 to above the middle of the leaflet and when visible serves 

 readily to distinguish this form from the associated leaflets 

 of similar shape but belonging to other species. 



The present species is not common in the collections but 

 is represented at Corocoro by several well preserved 

 specimens which are slightly larger than the type and show 

 more of the details of venation. It is very similar to the 

 existing Enterolobium timbouva Martius, a Brazilian 

 species ranging northward to the West Indies, and record- 

 ed by Herzog from the hill country of Velasco, in eastern 

 Bolivia. The genus is a small one closely related to Inga 

 and Pithecolobium, with about half a dozen existing species 

 of trees with even pinnate small leaves, confined to tropical 



