56 MISSOURI BOTANICAL GARDEN. 



from a strong beginning and gradually merging into 

 terminals, forming indefinite, generally large meshes. 

 Terminals, in young leaves, are exceptionally developed, 

 arborescent, curling. 



The veining as a whole is nearly even, somewhat zigzag, 

 whitish brilliant. Resembling glaucophylla closely, but may 

 be distinguished by the crenate venation, by the extreme 

 regularity of the looping even to the very tip, by the more 



terminals. — Plate 1, fig. 14. 



more 



Illustration from specimens supplied by Edwin Faxon, 



Esq., Boston, Mass 



Lauder 



dale, Wis., by M. S. Bebb, Esq., and herbarium specimens 

 in Missouri Botanical Garden, from different places. 



Group III. — Secondaries irregular. 



15. S. humilis, Marsh. — Primaries distant, dividing" 

 or branching, the arms forming loops, or, most frequently, 

 arches; costals usually several. Secondaries very irreo-- 

 ular. The tertiaries, well defined and strong, subdivide 



the space into large, irregular meshes which inclose 



iably well developed non-curlino; terminals. Comb- 



em ar 



terminals present in young leaves. 



As a whole, the venation is exceptionally strong, abun- 

 dant, in broken, angular, zigzag lines, — the best type of 

 irregular veining in our list. — Plate 3, fig. 15. 



Illustration from specimen of vicinity of St. Louis. 



16. S. tristis, Ait. — Primaries distant, rather irregu- 

 lar, very zigzag, sometimes dividing, arms forming very 

 wide arches. Secondaries usually irregular. Tertiaries, 

 with exceptions, undeveloped, meshes indefinite or large, 

 embracing faint, fading terminals. The veining, as a 

 whole, very irregular, very uneven and thickened at junc- 

 tions. In spite of the irregularity there is not usually a 

 sharp angularity in the meshes; the}' are mostly rounded or 

 polygonal. 



11 



