No. 2388. TERTIARY FOSSIL PLANTS FROM VENEZUELA— BERRY. 577 



extended its range northward from the Bahamas to Bermuda. On 

 the west coast of America it is found from southern California to the 

 Galapagos Islands. Rhizophora mucronata Lamarck ranges from 

 southern Japan to northern Australia and westward to eastern 

 Africa; Rhizophora conjugata Linnaeus is confined to tropical Asia. 

 Doubtless modern systematists will differentiate additional specific 

 forms, but judging by the rather uniform habits of these plants, such 

 differentiation will be based upon minor features. The mangroves 

 possess the singular ability of thriving in sea water, and their manner 

 of life and development have become well adapted both structurally 

 and physiologically to their mode of life, so that they have become 

 widely disseminated and individually abundant. In fact they are 

 the most remarkably specialized plants for their habitat that are 

 known and their specialization appears to have been in a measure 

 reached during the Tertiary period. 



It is possible that leaves of this genus may not have been recognized 

 although present in paleobotanical collections. However, since the 

 genus is almost exclusively tropical and most known Tertiary floras 

 are not strictly tropical, the geological record of Rhizophora may 

 be as meager as it seems. Only three fossil species have heretofore 

 been referred to Rhizophora and only one of these has any claim to 

 such an affinity. A single specimen was described by Massalongo 25 

 from the later Tertiary (Messinian) of the east coast of Italy, and a 

 second form was referred to this genus by Ettingshausen. The latter 

 came from the Ligurian-Aquitanian of Austria and was compared 

 with the existing Rhizophora parvifolia Roxburg of the East Indies. 26 

 The similarity of this form to various members of the Myrtaceae and 

 Leguminosae, however, led Schenk to express doubts as to its 

 identity. 27 The third and in my judgment only authentic fossil 

 species, Rhizophora eocenica Berry 28 was described from the upper 

 Eocene (Jackson) deposits of Georgia. The presence of a fossil 

 species in the later Tertiary of Venezuela serves to explain, if expla- 

 nation were needed, the presence of the modern mangrove on both 

 the Atlantic and Pacific shores of America. 



The present species is named for the collector C. F. Bowen, and 

 comes from Betijoque. 



Holotijpe.— Cut. No. 36442, U.S.N.M. 



» Massalongo, A., Studii sulla flora fossile e geologia stratigraphica del Senigalliese, p. 407, 1859. 

 •• Ettingshausen, C, Die Tertiare Flora von Haering in Tirol, p. 82, pi. 27, figs. 28, 29, 1853. 

 » Schenk, A., Zittel's Handbuch, Ab. 2, p. 032, 1890. 

 '■» Berry, E. W., U. S. Geo!. Surv. Prof. Paper 84, p. 141, pi. 29, figs. 1, 2, 1914. 



27177— 21— Proe.N.M.vol.59 37 



