440 ‘BOTANICAL GAZETTE [MAY 
Jurassic plants from Siberia (Amurland) makes a comparison of Alaskan and 
Siberian Jurassic floras possible. KNowLton concludes that the striking simi- 
larity between the Jurassic floras of northwestern North America and eastern 
Siberia shows that the land connection between these regions during the 
Jurassic must have been practically continuous. The Alaskan list recognizes 
12 genera and 17 species, the solitary species of Equisetum being described as 
new. The dominance of cycadophytes is obvious, so far as it can be inferred 
from so small a number of species, the list being as follows: pteridophytes 5; 
cycadophytes 11; and Ginkgo represented by a single species. 
SALISBURY® has described in detail a new species of Trigonocarpus obtained 
from the Lower Coal Measures at Shore Littleborough, England. In addition 
to the well marked features of the sclerotesta and sarcotesta, the nucellus is 
almost completely free from the integument, and has a well developed and 
thick walled epidermal layer, three longitudinal flanges corresponding with the 
commissures, and numerous secretory sacs in the ground tissue. The conclu- 
sion is reached that this species is more primitive than its congeners, and that 
the testa arose from the lateral fusion of a whorl of six originally free members. 
A discussion of the resemblances and differences between the Trigonocarpeae 
and the Lagenostomales reaches the conclusion that they are to be explained 
by intercalated growth, followed by subsequent fusion of the nucellus and 
integument. 
Dr. Stopes? has published a very interesting lecture upon the past and 
future of paleobotany, delivered at University College, London. The thesis 
is that paleobotany is now an independent — contributing to both botany 
and it and with its own important 
HOMAS and Bancrort® have made a "detailed comparative study of the 
cuticle of recent and fossil cycads, including also mention of other gymnosperms, 
especially with reference to the form and structure of the stomata. The 
see conclusion is that the characters presented by the stomata and epider- 
mal cells o gymnosperms are important as indicating to some extent their 
relatio eat Among the cycadophytes there are some characters which have 
undergone little modification from the Jurassic to the present time, and the 
authors conclude that stomatal structure is the expression of ancestral charac- 
ters rather than of purely local and temporary conditions of environment.— 
Ber Be 36 
® SALIsBurY, E. J., On the structure and ti f Trigonocar pus shorensis, 
sp. nov. A new seed from the Paleozoic rocks. Ann. Botany 28:39-80. figs. 8. 
bls. 4, 5. 1914 
7 Stopes, Marte C., Paleobotany; its past and its future. Knowledge 37° 
15-24. I914 
, ae. H. Hamsuaw, and Bancrort, NELLIE, On the cuticles of some recent 
and fossil cycadean fronds. Trans. Linn. Soc. London II. Bot. 8:155-204- figs. 32 
pls. 17-20. 1913. 
