K0.2229. FOSSIL PLANTS FROM BOLIVIA— BERRY. 133 



Mimosa microcep'hala Bonpland and with Mimosa iiectinata Kiinth. 

 It has also less aptly been compared with the existing Parldnsonia 

 aculeata Linnaeus, 

 Plesiotype.— Cat. No. 35090, U.S.N.M. 



MIMOSA MONTANOIDES Engelhardt. 



Mimosa monlanoides Engelhardt, Sitz. Naturw. GescU. Isis in Dresden, 1894, 

 Abh 1, p. 10, pi. 1, fig. 04. 



Description. — Leaves small, even pinnate. Leaflets tiny, obovate, 

 entire, 2 to 3 mm. in length by 0.5 to 1.5 mm. in maximum width, 

 sessile. 



This somewhat rare form was described by Engelhardt and is 

 apparently absent in the other collections from Potosi. It is of some- 

 what doubtful botanical aflmity, but is compared by its describer 

 with the existing Peruvian species, Mimosa montana Humboldt, 

 Bonpland, and Kuntn. 



Genus MIMOSITES Bowerbank. 



MIMOSITES ENGELHARDTI, new name. 



Plate 15, fig. 22. 



Mimosites linearis Engelhardt, Sitz. Naturw. Gesell. Isis in Dresden,. 1894, 

 Abh. 1, p. 13, pi. 1, figs. 21, 35 (not M. linearifolius Lesquereux, 1878= 

 M. linearis Knowlton, 1898). 



Description. — Leaflets sessile, linear-lanceolate, slightly inequi- 

 lateral, with an acuminate-cuspidate tip and an acuminate base. 

 Margins entire. Texture coriaceous. Length, 12 to 15 mm. Maxi- 

 mum width, 2 to 3 mm. Midrib relatively stout. Secondaries 

 obsolete by immersion. 



The name of this species appears to be preoccupied by the Mimo- 

 sites linearifolius of Lesquereux ^ from the Green River Eocene of 

 Wyoming which Knowlton ^ amended to Mimosites linearis in 1898. 

 While Engelhardt named his form in 1894, it seems desirable to rename 

 it in order to avoid confusion, and I therefore take the liberty of 

 calling it engelliardti as a slight token of esteem for the labors of M. 

 Engelhardt. 



This species is abundant at Potosi, always in the form of detached 

 leaflets, and it occurs sparingly at Corocoro. It is very similar and 

 liable to be confused with other leguminous leaflets found at Potosi — 

 namely. Acacia uninervifolia Engelhardt, Machaerium eriocarpoides 

 Engelhardt, and Enterolohium grandifoUum Engelhardt. The first 

 is more narrowly elongate and lanceolate, with more prominent 

 camptodrome secondaries. The second is relatively shorter and 

 wider, petiolulate, more lanceolate, and with more prominent sec- 

 ondaries. The third is larger, more inequilateral and more lanceolate. 



Plesiotypes.— Cat. No. 35091, U.S.N.M. 



I Lesquereux, L., Tertiary Flora, 1878, p. 300, pi. 59, fig. 7. 

 » Knowlton, F. H., Bull. 152 U. S. Geol. Survey, 1898, p. 144. 



