Ment of fu 
ted is ripe 
0d two from the 
Maller as am Bac showing one large embryo on the 
IRs '4, Neen FEL | 7 ea 
1898] POLVEMBRYONY AND ITS MORPHOLOGY | 227 
structures from the most different morphological origins. In its 
independent appearance in distinct groups it is comparable with 
the appearance of heterospory, but whether polyembryony like 
hetetospory will lead to some higher condition remains to be 
seen, though we shall not see it. 
_ Suite CoLLeGE, NORTHAMPTON, Mass. 
BIBLIOGRAPHY. 
Braun, A.— Ueber Polyembryonie und Keimung von Ceelebogyne. 1860. 
HEGELMAIER, F.— Zur Kenntniss der Polyembryonie von Ad/ium odorum 
L. Bot. Zeit. 55 : 133. 1897. 
Hupert, E.p’.— Recherches sur le sac embryonnaire des plantes grasses. 
Ann. Sci, Nat. VIII. 2: 37. 1896. 
JeFFRey, E. C.— Polyembryony in Erythronium americanum. Ann. 
Bot. 9 : 537, 1895. 
een, E.— Ueber Polyembryonie. Zeitschr. f. Naturw. 12: 647. 
TRETJAKow, S.— Die Betheiligung der Antipoden in Fallen der Poly- 
embryonie bei Allium odorum L. Ber. d. deutsch. Bot. Gesells. 13 : 13- 1895. 
A fuller bibliography and references may be found in Tretjakow. 
EXPLANATION OF PLATE XVI. 
egy all drawn with camera lucida, and the original drawings reduced 
In all of the figures, ¢,s. = embryo sac; #. = nucellus; é#. = the integ- 
as ® collectively ; 2, 7. = inner integument ; #. = micropyle or micro- 
em through the nucellus ; #. = pollen tube ; 7 protoplasm of 
Sac, : 
Figs, ; aa 
tral size. ‘2, 3,4, 5, each showing the embryos from a single seed, na 
Fig. ‘ : : 
di 6. Median section through an ovule of Opuntia vulgaris, some- 
“grammatized, six times natural size : f = funiculus; 4 = attach- 
hiculus to ovule; x = portion of nucellus not absorbed when 
Bis 
‘S-7. Embryo sac showing three embryos, one from the micropylar end 
F wall. x 18 
1G, 8, wall and several 
the micropylar end. x 18. Not a section, but a half seed laid 
