284 



ANNUAL EEPOET SMITHSONIAN INSTITUTION, 1915. 



Ortega's original figure of Eysenhardtia polystackya^ showing the 

 young leaves with stipels at the base of the leaflets, the flowers in 

 spicate racemes just beginning to bloom, and the reflexed seed pods, 

 together with details of the flower and fruit, is reproduced in the 

 Journal of the Washington Academy of Sciences, vol. 5, page 512, 

 figure 1, 1915. 



VARIABILITr. 



Eysenhardtia jyolystachya, as understood by the author, is remark- 

 ably variable in size and form of leaves, density of pubescence, and 



appearance of seed j)ods. It some- 

 times occurs as a stunted bush with 

 very small leaflets, sometimes as a 

 spreading shrub with straight stems 

 and recurved branches, and some- 

 times as a slender tree of dimen- 

 sions sufficient to furnish a valuable 

 cabinet wood. 



A distinction has been made be- 

 tween the forms having reflexed 

 seed pods, as shown in plate 3 and 

 in figure 1 &, and those with ascend- 

 ing or spreading pods, as shown in 

 figure 3; but in certain localities, 

 as in the barrancas of the State of 

 Jalisco, closely allied forms occur 

 almost side by side, some with re- 

 flexed and others with spreading or 

 ascending seed pods; but the latter 

 can never be confused with the 

 closely appressed pods of the dwarf 

 Eysenhardtia texana^ shown in fig- 

 ure 1 a. Figure 3 shows a subgla- 

 brous form with very pronounced 

 glandular dots on the leaflets and 

 with spreading seed pods almost 

 twice as large as those of the typical plant. 



On account of this tendency to vary it is difficult to delimit the 

 species. It is quite certain, however, that Eysenhardtia texana 

 Scheele, the type of which was collected by Lindheimer in the vicinity 

 of New Braunfels, Texas, is a valid species quite distinct from E. 

 folystachya of central and southern Mexico. Figure 2 shows the 

 fruits of the two species side by side, a, Eysenhardtia texana in 

 fruit, drawn from a specimen of the type collection, showing the 

 appressed subfalcate pods; 5, Eysenhardtia polystachya^ showing 



Fig. 2.— Fruits of Eysenhardtia. a, Ascending 

 pods of E. texana; b, reflexed pods of E. poh 

 ystachya. 



