No. 457.] EMBRYO OF THE ANGIOSPERMS. 19 
Ramaley (:02), who for the past ten years has been working 
on the comparative anatomy of dicotyledonous seedlings, ex- 
presses his opinion on this subject in the following statement : 
“] think also that the theory of the above named writer [Pres- 
ton, : 02] to account for the lobing of cotyledons is of no great 
value. He suggests that the lobing of the foliage leaf is 
‘thrown back’ upon the cotyledon. This assumes firstly that 
‘throwing back ’ can actually occur, while as a matter of fact it 
yet remains to be proven; and secondly, that the cotyledons 
are homologous with leaves, something which also remains un- 
proven. The suggestion! concerning the morphology of the 
cotyledon made at the recent Chicago meeting of botanists of 
the central states seems more reasonable than the one which 
would consider the cotyledons as really a leat." 
Many other writers have expressed dissatisfaction with the 
foliar theory without taking a decided stand against it. Klebs 
(83) in his excellent treatise on germination pronounces the 
subject an enigma, while Lubbock (92), who has undoubtedly 
made more extensive observations upon seedlings than any 
other one man, writes: * No one who has ever looked at young 
plants can have failed to be struck by the contrast they afford 
to the older specimens belonging to the same species. This 
arises partly from differences in the leaves, partly from the con- 
trast which the cotyledons, or seed-leaves, afford, not only to the 
final leaves, but even to those by which they are immediately 
followed. This contrast between the cotyledons and true leaves 
is so great that one might almost be pardoned for asking 
whether they can be brought in correlation. So far, indeed, 
are the cotyledons from agreeing with the forms of the leaves, 
. that the difficulty is to find any which have been clearly influ- 
enced by them. One species of Ipomoea (I. Pes-caprae) has 
both cotyledons and leaves, as the name denotes, somewhat like 
the foot of a goat; but the leaves vary considerably, and it is 
probable that the resemblance may be accidental. A clear case 
is, however, afforded by the Onagrariez, where in CEnothera 
and some allied genera the form of the mature cotyledons is 
! Lyon (:02). 

