hg] The Embryo-Sac in Acer rubrum. 375 
| the Old World. Of course it is to be expected that Junipe- 
“fuscommunis, which is indigenous in both Europe and Asia 
inall regions. § Fyziperus rigtda Sieb. & Zucc., of Japan, 
@ ‘parently also passes three seasons before arriving at matur- 
- ity; but it seems hardly likely that ali the species usually 
_tassed in this section, Oxycedrus, take so long before reach- 
-iigfull development. In the genus as a whole, probably a 
_ large proportion of the species ripen their fruits at the eyd of 
the second season: and there are others, besides Juniperus 
--Vitginiana, which mature their fruit in the same year in which 
y blossom, 
It is almost impossible to determine these points with ac- 
nary herbarium specimens as they are gener- 
,and, in making a study of the length of time re- 
F Wed by the fruit of different species to arrive at maturity, 
alum material should b 
this character; 
- Matefully obsery es 
; “ed me “tcompanying plate and other assistance I am in- 
-Rbted to My. Se 
Be Arbor elum, Harvard University. 
| AMTION oF PLATE XXXIII.—Fructification of /uniperus communis L 
sbuatigg Fig.. 2. F 
with flowers. emalé"branch, flowers and 
4. Fruit, one year old. ¢. Fruit, two years old (May 25). 
n. Fig. ged. Fig. 4. 
Oo 
2 
g 
“a 
e 
i i ; flow- 
Pas “oni eae ’ Fig. 8. Fruit two years after fl 
q toning resin Section, enlarged. Fig. 9. Seed, two years from flowering, 
: glands on the back, enlarged. 
ta ierapalataininiddsina ess’ cso 
Development of the embryo-sac in Acer rubrum. 
DAVID M. MOTTIER. A 
' Asis WITH PLATE XxxIv. 
Nbray Y of the development of the embryo-sac of Acer 
4 the Presents in itself nothing new or striking, we 
3 Y witha sPoint of comparative morphology it 1s or 
a seticg as Interest, This work represents only a a 
: ; of Similar investigations to be made upon atone 
s a OF both related and widely separated families. 
