GENTIANALK.S. 



343 



to its ('xtnniic base, fonniiiii; jictiolar wings, 

 each from 1 to 2 milliinetcrs wide. Leaf tex- 

 ture suhc'oriaceous. Petiole stout, grooved, 

 about 2 centimeters in Iciigtli. Midrib stout 

 below, becoming tliin in the upper part of the 

 leaf, longitudinally striated, somewhat jirom- 

 iuent on the lower surface in the proximal half 

 of the leaf. Secondaries thin, largely immersed 

 in the leaf substance: 15 to 20 irregularly 

 spaced and mostly alternate pairs diverge from 

 the midrib at angles of about 45°, cuning 

 slightly outward and then upward, campto- 

 drome in the marginal region. Tertiaries not 

 weU marked; some are ])arallel and between 

 secondaries and others percurrent; they are 

 fuie and largely immersed. 



This species is readily s(>paraljle from tlie 

 other Wilcox species of Apocynophyllum, its 

 peculiar decurrent base alone rendering it 

 easily recognizable. It is intermediate in its 

 resemblances between ApocynophijUum sapin^ 

 difolium Hollick and Apocynophijlluin, tahd- 

 larum (Lescjuereux) BeiTV. It is less ol)long 

 in outline than either species ; the secondaries 

 are more numerous than those of sapindi- 

 foliuin and mucli fewer than those of tahellarvm. 

 It is not common in the coU(>ctions. 



Occurrence. — Grenada fonnation, Grenada, 

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

 Lowe and E. W. Berry). Wilcox group, U 

 miles northeast of Mansfield, De Soto Parisii, 

 La. (collected by G. C. Matson). 



Collections. — U. S. National Mus(>um. 



Apocynophyllum tabellarum (Lesquennix). 



J'latcs CIl, figures 2-5, and CIII, figure 5. 



Salix tabcllaris. Lesquereux, Am. Philos. Soc. Trans., 

 vol. 1?., p. 411, pi. 17, fig. 4, 1869. 



Description. — Lestiuereu.x's description . pub- 

 lished in 1869, is as follows: 



Foliis clongatis, ultra pollicaribus latis, liiioarilnis, raar- 

 gine parallcliiS, integerriini.s, in pctioluni altomuilis; norvo 

 medio lalo, norN-is seeumlariis numerosis, irregularil)us, 

 angustis, camptodromis. 



The type, from the "soft wliite clay of Lafay- 

 ette County, Miss.," was collected by Ililgard 

 and described by L(?squereux. It probably 

 consisted of the single specimen figured, wliich 

 I have not b(>en a])le to find in tiie remains of 

 the Hilgard collection at Oxford, Miss. Addi- 

 tional material has l)een found in abundance 

 in the clays at Pmyear, Tenn., and elsewhere, 



and tlie species may be soiuewliat more fully 

 characterized as foUows: 



Leaves ol)long-lanceolate in outl'ne, the 

 apex short ])ut sharply pointcnl and the liase 

 more narrowly pointed and sliglitly decurrent. 

 Length about 17 centimetei-s. Maximum 

 widtli a])()ut A centimetei-s, the average ])eing 

 somewhat less than tliis (igure. Margins entnc 

 l)nt slightly undulate, deeply constricted in one 

 s])ccinien. Petiole short and stout, less than 

 1 centimeter in length. Midrib stout, ])ronii- 

 neiit on the lower surface of the leaf. Second- 

 aries tliin, very numerous, somewhat irregidarly 

 sijaced, subparsiUel; they cUvei-ge from the 

 midrib at angles of about 60° at uitervals of 

 1 to 3 millimeters and run outward with only 

 a shght cur^'ature to tlie margimd region, where 

 they curve upward parallel vnili it to form a 

 series of rapidly reduced camptodrome arches. 

 Tertiaries mostly obsolete, mdistinctly sliown 

 in one of the figured specimens. Texture co- 

 riaceous. 



Lesquereux compared this species with the 

 European Miocene Sali.c longa iVlexander 

 Braun, and thought that it might even be a 

 variety of that widespread type. The species 

 is obviously not related to Salix longa nor is it 

 even a Salix in either size, outline, venation, 

 or texture. It is, however, closely alUcnl to a 

 number of tropical American genera of the 

 Apocynaceas and very close to the numerous 

 Tertiary species, of which at least two score, 

 mostly European forms, have been described. 

 American fossil species are uncommon. Lcs- 

 cjuereux ' described Apocynopliyllum scudderi 

 from the Green River formation of Wyoming. 

 It is very chstmct, however, from any Wilco.x 

 species. IloUick - referred a fragmentary speci- 

 men from this horizon m Louisiana to Apocyno- 

 pliyllum, and though I have since collected more 

 complete material, the generic reference can 

 not be said to be conclusively established. 

 ApocynopliyUum sapindifoliwm HoUick has the 

 same general outlmc but is a smaller leaf and 

 has a more obtuse apex, longer petiole, ami 

 less numerous, relatively distant secondaries. 



ApocynopliyUuni tahellarum suggests to a 

 certain extent some American species of the 

 genu's Chrysophyllum of the Sapotaceaj, and 



• Lesquereux, Leo, The Cretaceous and Tertiary Qoras, p. 172, pi. 4.5a, 

 fiSS. 1-5, 18S3. 



- Hollick, .\rthur, in Harris, G. !>., and Veatch, .\.C., Aproliininary 

 report on the geology of Louisiana, p. 288, pi. 46, fig. 3, 1899. 



