ALASKA GEOLOGY 
156 
serrate above ; midrib very thick and strong; secondaries very numer¬ 
ous, 25-30 pairs, thin, mostly alternate, those in the lower, narrower 
basal portion being often at a slight angle, those above arising nearly 
at an angle of 45°, running nearly or quite straight to within 13 mm. 
of the margin, then turning abruptly upward to end in a marginal 
tooth; secondaries often with two or three slight branches very near 
the margin, which pass to marginal teeth; nervilles numerous, strong, 
both broken and percurrent; finer nervation not clearly preserved. 
A number of examples, some of them nearly perfect, represent this 
species. They all seem to be of about the same size. The nearly 
perfect leaflet figured is 20 cm. in length and about 9 cm. in width. 
It is well shown in the figure. 
Family STERCULIACEiB 
Pterospermites magnifolia sp. nov. 
pi. xxxi. 
Leaves very large, coriaceous, ovate-cordate, obtusely acuminate at 
apex; margin coarsely and irregularly toothed, the teeth low and 
obtuse; midrib very strong, straight; secondaries strong, about 14 
pairs, mostly alternate, those at the base clustered, emerging at a right 
angle or falling below one, those above at an angle of about 45 °, 
slightly curved upward, craspedodrome, ending in the large marginal 
teeth; nervilles numerous, strong, mainly percurrent and at right 
angles to the secondaries ; finer nervation obscure. 
This species is represented by the largest leaves in the collection, the 
figured example being 23 cm. in length and about 14 cm. in width. 
Other specimens are 20 cm. long and 14 cm. wide, and there are frag¬ 
ments that would seem to indicate a still larger size. 
Pterospermites alaskana sp. nov. 
pi. xxvi, fig. 2 ; pi. xxxii. 
Leaves of large or medium size, thick, coriaceous, ovate or ovate- 
oblong, obtusely wedge-shaped or rounded at base, obtuse at apex; 
margin coarsely dentate, the teeth somewhat irregular, very flat and 
obtuse at the point; petiole strong; midrib rather thin for the size of 
the blade, perfectly straight; secondaries 11 or 12 pairs, thin, alter¬ 
nate, at an angle of about 45 0 , little if any curved upward, cras¬ 
pedodrome, ending in the large marginal teeth, occasionally with one 
or two short branches on the lower side near the margin; nervilles 
moderately numerous, usually broken, though often percurrent but 
curved on crossing; finer nervation obscure. 
