thes] THE GROUPS OF ANGIOSPERMS 339 
Before entering upon a discussion of the sequence of series 
athe monocotyledons and dicotyledons, I wish to speak of the 
lagnostic importance which is being laid upon the development 
ithe pollen-tube in the ovule, and the structure of the ovule 
nthrespect to the development of the integuments. Inthe first ~ 
lew series of Archichlamy deze (2. é., the Piperales, Verticillate, 
Fagales, Juglandales, Myricales, Salicales, Urticales, Proteales, 
Satalales, and Aristolochiales) the pollen-tube and the ovules 
Sow relations which never occur elsewhere in angiosperms. 
‘Sforthe chalazogamy of Treub, the investigations of Nawa- 
“tinand others have greatly depreciated its importance from 
‘he standpoint of classification, and of late more importance has 
een laid upon the peculiar conditions which occur in the Santa- 
. and Loranthacee in the development of ovules and 
fabryo sacs, as set forth by Van Tieghem, who distinguishes a 
Manerogamous division ‘‘ Inovulées” to which the Loranthacee 
"i Balanophorace belong, and another division “ Innucellées,”’ 
‘hich about corresponds to our Santalacee. 
Por my part, I do not see sufficient importance in either of 
tse sets of characters to justify the establishment of subdivi- 
‘Sof the first rank. Nor in the fact that in the Loranthacee 
“embryo sac is developed within the tissues of the carpel do 
™ peculiarities which justify setting these plants apart as 
ty the remaining dicotyledons and monocotyledons. 
Sd regard them as dicotyledons which, like all other 
: thi are Opposed in many respects to monocotyledons, 
. . the development of the ovules show certain depar- 
.. lf own. We can no more found a higher systematic 
: More or less complete development of the ovule 
‘ | © Presence of endosperm and perisperm, or on the 
“ther. €ss advanced development of the embryo of the 
Pa Pent. -Indeed. if the gymnosperms stand in close rela- 
pee ‘0 the teridoph . a : d ovules with 
ak ophytes, since normally develope ae 
sume th integument occur in the gymnosperms, it 1s eset 
des ig a a the peculiar development of ovules in the Santa- 
: “'Y @ phenomenon of reduction. 
