F 1893.) : Briefer Articdes, 315 
which may reach 30". The anatomy of the lower part of 
thisstem was, however, like that of a rhizome. The scape 
varies in outline from terete to triangular, and shows fre- 
quently a conspicuous furrowing. The cells of the mechani- 
cal tissue differ from typical stereome-cells by their length 
and having their pores transverse. This has hitherto only 
been observed in the Restiaceac.* 
The leaves show also several variations. They are, in re- 
_ gard to the arrangement of the tissues, centric, excepting in 
_ Abolboda brasiliensis, where they are dorsiventral. 
The author discusses also the geographical distribution of 
the various species. While the genus Adolboda is restricted 
to South America, Yyris has been recorded from all parts of 
the world excepting Europe. One hundred and eleven spe- 
“es are enumerated of Xyrzs,and seven of Abolboda. Twenty- 
one are described as new to science. 
pis ri a previous note, entitled: ‘Ueber die Afrikanis- 
"Ua Arten der Gattung Xyris*”, to which we hereby take 
°pportunity to call attention. —THEO. HOLM. 
BRIEFER ARTICLES. 
“eto full Lake Biological Station of the University of Minn.— 
tomical lib ng ELopga CaNnaDENsIs.—In the absence of my ana- 
hairs in ea and periodicals I cannot say whether the presence of root- 
bre 4 vhas been made out or not. De Bary in his Compara- 
Tot. Me (ens: tran. P- 55, 1884) seems to except E/odea from the 
lants, saying, “If we disregard the root-hairs which, 
: o Ptions (Zlodea, Lemna, Ophioglossez) are univer- 
Lipp, “onan and Van Tieghem in his Traité de Botanique, 
Poils rad i “quelques plantes se montrent méme dépourvues 
Telodée Oa pe bien si la racine est aquatique, comme dans 
these hile I do not yet know upon whose observation 
Elodeg ae are based, I can state that they must be corrected, for 
NSis 8towing in the outlet stream of Cullen lake, Cass 
ASTERS 
"M. 
Ratie, Journ, yacrvations on the Morphology and Anatomy of the Genus 
 MOhenigt * S0e. vimt. (1865). Pl. xrv, fig. 1. 
pass af Kgl. s 
venska Vet. Akad. Forhdlgr. Stockholm 1891. m0. oe 
