USGS11617.11 Indet. HAPLD150

Notes

USNM 406791

 

Locality

Locality Map

USGS11617

Lat. 60° 31' 45"N  Long. 165° 06' 00"W

Nunivak Island (C-1) Quad.

Description

Leaf:  simple; symmetrical; very wide obovate, trilobed; apex missing (?); base acute; margin serrate except in the basal quarter of the leaf where it is entire; teeth small (< 1 mm) with obtuse angular apices and wide shallow rounded sinuses, apices showing evidence of a swollen tip; venation suprabasal perfect marginal actinodromous; primary midvein moderate, more or less straight for two-thirds of the lamina length, becoming sinuous or zigzag near the apex, changing direction at the point of departure of the superior secondary veins; pectinal veins arising at an angle of 45-55°, moderate, slightly weaker than the primary at their point of departure which is approximately one-third of the length of the lamina above their base, recurved immediately after departure from the midvein then curved more or less uniformly for most of their length, the degree of curvature becoming greater near the apex so that the pectinals curve inwards towards the apex, moderate pectinal abmedials given off at angles of approximately 45°, curved, the degree of curvature increasing near the margin and joining the superadjacent abmedial at approximately 90°, third and fourth order arches also present; the superior secondaries given off at an angle of 45° and curved like the pectinals; inferior secondaries, approximately six pairs, also arising at 45° but immediately recurving so that the main course of the vein is at 90° to the midvein before curving near the margin to form arches by joining the superadjacent inferior secondary at approximately 90°; third and fourth order arches also present; tertiary veins percurrent, straight or convex, often forked, joining both ad- and abmedial sides of the lower order veins at approximately 90°; fourth order veins indistinct.

Remarks

Of the published leaf forms only 'Platanus' heeri (Lesquereux, 1874, p. 70; Plate 8, Fig. 1 not Fig. 4; Plate 9, Figs. 1, 2) exhibits any similarity to these forms but the differences are so great that they should not be considered to represent the same.  Lesquereux's specimens lack the wide basal development of the lamina along the petiole accompanied by the strong series of inferior secondaries, and both the pectinal veins and superior secondary veins are straighter.