248 



LOWEK KOCENK FLOKAS OF SOUTHEASTERN NORTH AMEHU'A. 



forkins; morge with tlio tortian' system in the 

 marginal rcgiun. The basal two oi' three pairs 

 of secondaries originate close together at the 

 base of the leaf, and one pair, generally the 

 third, are somewhat stontor, more ascending, 

 and longer than any of the others, giving the 

 leaflets a |)alniately triveined appearance, as 

 in so many lauraceous and other genera. 

 These veins are not lateral primaries, however, 

 and the sum of the characters of the specimens 

 indicates their leguminous nature. Tlie ter- 

 tiary vems are tliui l)ut weU marked and inoscu- 

 late to form the typical papilidiiaceous vena- 

 tion of this species. 



In its outline this species suggests various 

 Wilcox Leguminosa\ from all of which it differs 

 in its venation characters, especially in its 

 triveined appearance. It may be compared 

 with existing species of Machan-ium, Drepano- 

 carpus, Pterocarpus, and the like, as well as 

 certain members of the Phaseolese. 



Occurrence — Grenada formation, Gre ada, 

 Grenada County, Miss, (collected by E. N. 

 Lowe and E. W. Berry). 



Collection. — U. S. National Museum. 



Genus CANAVALIA Adanson. 



Canavalia eocenica Berry, n. sp. 



Plate LIII, figures 3-6. 



Description. — Stem elongated, probably trail- 

 ing or scandcnt. Leaves trifoliate. Leaflets 

 variable in size, elliptical in outhnc, the apex 

 broad, emarginate or retuse, and the base 

 rounded or very broacUy and obtusely pointed. 

 Petiole stout, al)out 1.5 centimeters in length, 

 slightly tumid proximad. Petiolules stout, 

 with narrow and thick marginal \\nngs, con- 

 stricted at base of leaflets, 4 to 12 milhmetcrs 

 in length. Leaflets range in size from 4.5 to 8 

 centimeters in length and from 2. .3 to 4.7 centi- 

 metei's in maximum width, which is midway 

 between the apex and the base. Midribs stout 

 and prominent on lower surface of the leaflets, 

 appearing narrow on the upper surface. Sec- 

 ondaries thin, remote, five or six subopposite 

 to alternate pairs, diverging from the midrib 

 at angles of about 45° or more, curving regu- 

 larly upward, subparallel and camptodrome. 

 Margins entire. Texture coriaceous. 



This fine species is entirely distinct from prc- 

 \nously described fossil fonns. The detached 

 leaflets arc common in th(^ clays of Henry 



County and might readily ho confused ^\'ith 

 sa])otaceous leaves like tiiose of Mimusops or 

 \dth Sophora, Chrysobalanus, or Capparis. I 

 was fortunate enough, however, to find a com- 

 l^lete specimen, which had all three leaflets 

 intact. Tills is shown in Plate LIII, figure 6, 

 after the terminal leaflet was destroyed in 

 ti-ansit. When the pctiolule is not broken off, 

 the detached leaflets may be distinguished from 

 inirelated genera with similar leaves by the 

 enlarged lateral margins of their petiolules. 



Among existing species tliis Eocene form is 

 unquestiona])ly closely alhed to Canai'alia 

 ohtuaifolia (Lamarck) De Candolle, a widely 

 distributed tropical strand plant common in the 

 West Indies, creeping over the beach ridges and 

 climbing in the thickets in the beach jungle, 

 comparable in its abimdancc, range, and habi- 

 tat with Ipomaa pes-capne. 



This modern species is identical in character 

 ^vith the fossil form, except that its leaflets are 

 relatively shghtly broader, the petiole is some- 

 what longer, and the rachis extends a short 

 distance above the point of attaclnnent of the 

 opposite lateral leaflets. The size, textm^e, 

 and venation are exactly comparable, and some 

 of the broader leaflets, like the larger one fig- 

 ured, are identical in outline. The leaves of 

 the recent form are not deciduous, but the 

 leaflets commonly absciss after repeated wet- 

 ting, and a similar habit would account for the 

 presence of the commonly detached leaflets in 

 the clays of Wilcox age in Tennessee. 



Another existing species, Canavalia cnhensis 

 Grisebach, has leaflets relatively narrower than 

 those of Canavalia- ohtusifolia. They are ellip- 

 tical and identical with the average of those of 

 the fossil species but are as a rule merely ob- 

 tuse and not emarginate distad. Canavalia 

 cubensis is a common high climber of the moun- 

 tains of Cuba but in some places clambers over 

 coral rock at sea level along the coast. 



At least three of the existing species are 

 littoral and are dispersed by ocean currents. 

 The pods and seeds of Canavalia, ohtusifolia 

 float well and the seeds retain their vitality 

 after prolonged immersion in sea water,' so 

 that the wide dispersal of this species is un- 

 doubtedly largely due to this liabit. 



An unrelated mod(>rn form with trifoliate 

 leaves, and leaflets identical in outline with 



I fltippy, n. B, op. rit. ,p. 14.'i. 



