26 MISSOURI BOTANICAL GARDEN. 
in the pith are added to those observable in the buds and 
bark.* 
Professor Britton, in an article published in 1888, restor- 
ing the Rafinesquian name Hicoria for the genus which 
had so long been known as Carya,t bases a primary sub- 
division of the genus upon the location of the staminate 
catkins, this grouping being somewhat different from that 
of De Candolle. It seems to me, however, that the bud, 
fruit, and inflorescence characters are complementary to one 
another, the lateral umbels of the Pecan, which were 
held by Britton to be peculiar, resulting merely from the 
abortion of many of the shoots on which they are basal, 
and I am glad to see that Professor Sargent, in his recent 
treatment of the genus, has come to substantially the same 
conclusion. In the following pages, therefore, Britton’s 
subgenus Pacania has been amplified so as to include all of 
the species comprised in the section Apocarya as understood 
by DeCandolle.{ This being done, Eucaryaof De Candolle 
and Engler, and Euhicoria of Britton, have an identical 
limitation. In the main I quite agree with Professor Sar- 
gent § in the limitation of species, and the nomencla- 
ture of the Silva is followed unless the contrary is specifi- 
cally stated, so that this paper is not incumbered with the 
detailed synonymy of each species, which can easily be 
ascertained by reference to the Silva. 
During the past year Nawaschin || has ascertained that 
the pollen tube of Juglans regia reaches the embryo sac 
by growing through the walls of the ovary and the chalaza 
instead of passing through the cavity of the ovary and the 
micropyle, a phenomenon previously discovered in Casu- 
arineae, Myricaceae, Betulaceae, etc., and supposed to 
* See Beal, American Naturalist, xv. 32. 
t+ Bulletin of the Torrey Bot. Club, xv. 277. 
t See also Engler & Prantl, Pflanzenfamilien, iii. (1), 25. 
§ Sargent, Silva of North America, vii. 132, 134. 
|| Bot. Centralblatt, lxiii. 353-7; Smith, Am. Nat. xxix. 1103; Goodale, 
Am. Journ. Sci. 3 ser. 1. 429. 
