1907] BRIEFER ARTICLES 209 
of the second year for a lateral conelet. The species is uninodal and bears 
subterminal conelets. 
It is not the purpose of this article to discuss the merits of Mayr’s 
very interesting arrangement of Pinus except so far as it involves the false 
node and its cone, on which his section Murraya is mainly founded. It 
serves to illustrate, however, the elusive character of the “lateral cone,” 
which should be regarded as an incident, more or less persistent, in the 
life of a pine, rather than as an invariable character—GroRGE RUSSELL 
SHAW, Arnold Arboretum, Jamaica Plain, Mass. 
THE GENUS ALISMA IN NORTH DAKOTA 
(WITH ONE FIGURE) 
As the basis for this investigation I have used BUCHENAU’s monograph.? 
According to his analytical key, Echinodorus has 6, 9, 12, or more stamens, 
and the carpels are arranged in a dense head; while Alisma is characterized 
by 6 stamens, and has the carpels placed in a circle. Consequently he 
has changed the name Alisma tenellum Martius to Echinodorus tenellus 
(Mart.) Buchenau. He refers all the other forms of Alisma to A. Plan- 
fago L. and has divided this species into three varieties: var. a Michaletii 
Aschers. et Graebn.; var. 8 arcuatum (Michalet) Buchenau; and var. 
¥ parviflorum (Pursh) Torr. He says that var. arcuatum “‘is distinguished 
by many special small characters” from the other varieties. As will be 
found below, some of these differences are most conspicuous and give to 
the plant a peculiar aspect, and the distinguishing characters are constant 
and extend to all parts of the plant. I have therefore restored this variety 
to its former specific rank, and believe that the following will be an accept- 
able ‘gpl 
. Pedicels forming with the scape an com of 45° or less; styles erect, longer 
A. Pl 
oe the ovules . ‘antago (aquatica) L. 
2. Pedicels isneine wih ‘the jeaiie an n angle of go° or more; styles bent 
outwards in a hook, shorter than the ovules . . . A. arcuatum Michalet. 
1. ALIsMA PLantaco L., vide a s Pflanzenreich, |. c.—Scapes gen- 
erally solitary (seldom two), 15-100™ high, erect; strong, slender, fibrous, 
as is the whole plant, except when very young. Leaves bright green, ovate 
to lanceolate, with an acute apex and a rounded or cordate sometimes 
tapering base; petioles 2-35°™ long; the blades usually 7-ribbed, 5—17°™ 
long, 3-9°™ wide. Inflorescence a strict, large, loose, pyramidal panicle 
of majestic appearance, its lower part raised above the level of the leaf 
t BUCHENAU, FR., Alismataceae. Engler’s Pflanzenreich 4:no. 15. pp. 66. 1903. 
