MUSEUM OF COMPARATIVE ZOOLOGY. 45 



AMENTACE^. (APETALE^.) 



Betiilacese. 



19. Betula fallax, sp. uov. Leaves rhomboiJal-ovate, cuneate to the base and 

 narrowed in the same degree from the middle to the apex, penninervate ; lower 

 pair of secontlaries attached to the midrib above the base of the leaves and op- 

 posite, the others, 5-6 pairs, parallel, at variable distance, at an acute angle of 

 divergence, somewhat curved in passing toward the borders ; border distantly 

 dentate in the upper part of the leaves, the teeth short and turned up, being 

 marked only at the apices of the lateral nerves which are mostly simple, the 

 lower ones only with few branches. The species resembles in the form of the 

 leaves Betula nigra, Linn. The leaves vary from 3| to 5^ cm. in length; 

 from 2^ to 3| cm. in width in the middle. The angle of divergence of the 

 nerves is only 30°, and therefore the leaves are only dentate in the upper part, 

 at the points entered by the secondaries. 32 specimens. 



20. Betula Schimperi, sp. nov. Leaves small, as broad as long, round or 

 subcordate at base; ovate, acute, simply or doubly dentate; lateral nerves thick, 

 5 pairs, the three lower opposite, the lowest more or less branching outside, 

 all craspedodrome, as well as the divisions, entering the larger teeth directly 

 when simple, and the intermediate short ones by branches; curved in travers- 

 ing the areas at a broad angle of divergence. The leaves measure 2 to 3 cm. 

 across, both ways, and are deltoid-acute at the apex. The teeth, like the veins, 

 are somewhat distant, turned outside, sharply pointed, triangular. The base 

 of the medial nerve is pressed into the stone, and thus the leaves appear sub- 

 cordate ; but the base is really rounded and abruptly turned down to the ped- 

 icel. The surface is rugose by the deep impression of the nerves and ner- 

 villes, these being simple or branching in the middle. The relation of the 

 species is with Betula angulata, Goepp., Shoss. Fl., p. 10, Plate IIL fig. 3. 

 2 specimens. 



21. Betula. Species not determinable. 1 specimen. 



22. Alnus rugosa, sp. nov. Leaves membranous, elliptical-ovate, narrowed 

 to the base, undulate on the borders, pinnately nerved; lateral nerves equi- 

 distant, parallel, straight, craspedodrome, with few branches; surface rugose. 

 The leaves are about of the same size as those of A. nostratum, Ung., as figured, 

 Chlor. Protog., Plate XXXIV. fig. 1, and the nervation is of the same type; 

 but the leaves are narrowed, not rounded to the base. 2 specimens. 



23. Alnus carpinifolia, sp. nov. Leaves comparatively small, ovate-acute, 

 narrowed and abruptly short-decurring to the petiole, entire to the middle, 

 denticulate above ; lateral nerves equidistant, the lower pair much branching, 

 all parallel, at an acute angle of divergence, craspedodrome. 



The relation of the leaf is with that of Alnus cycladum, Ung., Fl. v. Kumi, 

 p. 23, Plate III. fig. 19, differing essentially by the base which is rounded, 

 and abruptly turned down to the petiole. The lower lateral nerves are joined 

 to the midrib a little above the base of the leaf. 1 specimen. 



