ROSALES. 



223 



stout, only about 1 millimotcr in l(>nf;th. 

 Midrib slender but well niarlxed. curved. 

 Secondaries tiiin but well marked, alxniti live 

 alternate pail's. The lower i)airs diver<;;e from 

 tlie midrib at acute anj^les, asceadins^ in long, 

 somewhat irregular eurs^es, caniptodronie; the 

 upper pairs diverge at a wide angle and are 

 nearly straight in their eoin-se to tlie pomt 

 where they turn upward to form campfodrome 

 arches. Tertiary venation fine but distinctly 

 marked, as shown in the specimen figured. 



Tliis weU-marked species is clearly unlike 

 previously described forms but not unhke 

 several existing .Imeriean species of Inga. 

 Among fossil fonns the only one tiiat ap- 

 proaches it closely is an undescrii)t'd sjiecies 

 from the Claiborne group of .Vrkansas, wliich 

 has the same general form but is slightly larger 

 and has a stouter venation, immei-sed tertiaries, 

 and a more coriaceous texture. It seems to be 

 genetically related to this Wilcox species. 



The fossil species of Inga are few. Inga 

 cretacea Lescpiereux of the Upper Cretaceous 

 is abimdant in the clays of the Tuscaloosa 

 formation of northwestern Alabama and is 

 somewhat suggestive of the present species 

 l)ut is larger, more regularly lanceolate, and 

 carries more numerous secondaries. Engel- 

 hardt ' has described a small-leafed species, 

 Inga ochseniusi, from the Tertiaiy of Bolivia. 



The existing species of Inga num]>er more 

 than 150. They are confuied to the Tropics 

 and subtropics of America and are common in 

 the West Indies but fail to r(>ach the United 

 States. 



Inga mississijrpiensis is very close to the small 

 leaf from Carbon, Wyo., figured by Lescjuereux- 

 as a form of his Ficus oblanceolata, a reference 

 that will be questioned by most students. 



A specimen of Inga mississippii'usi'i was 

 collected by Safford at Somerville, Temi., 

 many years ago and was iderrtified by Lesfpic- 

 reux as a leaf of the living Prunns caroliniana 

 Michaux. It does not at all resemble that 

 species and the determination was lai-gely 

 influenced by the idea that the deposits were 

 very recent and pi-oi)ably Pliocene. 



Occurrence. — Holly Springs sand, Early 

 Grove, Marshall County, Miss, (collectetl by 

 E. W. Berry). Lagrange formation (Ln beds 



' Engelhardt, nermann, Naturwiss. Gesell. Isis in Dresden Abb., 

 1894, p. II, pi. 1 , flfs. 39, 40. 

 2Lesquereu.\,Leo,TheTertiarynora.pl.2S,ng. 9 (not figs. 10-12), 1878. 



of Wilco.x; age), Somerville, Fayette (\)unty, 

 Tenii. (collected by J. M. Safford). 

 Collections. — U. S. National Museum. 



Inga rrmEARENsis Berry, n. sp. 

 Plate LI, rigurel2. 



DcKcri pfion . — Leaflets oblong-lanceolate, in- 

 ("(juilateral and slightly falcate in outluie, 

 abruptly narrowed to the mequilateral bluntly 

 pointed apex and to the ine(|uilateral cuneate 

 base. Length about 6.5 centimeters. Maxi- 

 mum width, at f)r l)elow the middle, about 2.2 

 centimeters. Margins entire, slightly undu- 

 late, the outer longer, fuller, and more curved 

 tlian the imier. Texture sul)coriaceous. Peti- 

 olule wanting. Midrib st on t, somewhat curved, 

 especially cUstad, prtuninent on the lower 

 surface of the leaflet. Secondaries relatively 

 stout and pi-ominent, five or six iiTcgularly 

 spaced and generally remote, oppt)site to 

 alternate paii-s: they diverge from the midril) 

 at dift'erent angles, which are acute in the 

 lower part, of the leaflet but more open toward 

 its tip. Tlie lower secondaries are slightly 

 curved, elongated, ascending sid)parallel with 

 the lower lateral margins and eventually 

 camptodrome. Their angles of divergence 

 range from 30° to 50°. The upper two or 

 three secondari(>s diverge at angles of about 

 60° and describe short, even, camptodrome 

 curves. Tertiaries thin, relatively straight, 

 percurrent at nearly right angles to the midrib. 



iVlthough several species of Inga are known 

 from the Wilcox group, they are chiefly repre- 

 sented by a few leaflets, which are generally 

 detached. The present species is most like 

 Inga mississippiensis Berry but is larger and 

 coai"ser and has a more prominent venation 

 and fewer secondaries, the apex is much more 

 abruptly pointed, and the basal lamina is fuller 

 on the inner insteatl of on the outiu- side of the 

 midrib. It is very much larger, less coria- 

 ceous, less inequilateral, and more oblong in 

 form than Inga wickliffensis Berry, which also 

 has more numerous, much thimier, and much 

 less ascending secondaries. It is much smaller 

 and less in<^quilateral than Inga laurinaJ'oUa 

 Berry and has less numerous and much more 

 ascending secondaries, which arc also more 

 prominent. It is much like several existing 

 species of Inga of the American Tropics. 



Inga puryearensis closely resembles and is 

 possibly ancestrsil to Inga arkansensis Berry of 



