52 Mr. A. Ilenfrey on the Progress of Physiological Botany: 
above, and the upper part of the tubes thus remains destitute of 
granular matter or fertilizing fluid, because the latter is always 
carried toward their lower extremities. To the objection that the 
tubes are too numerous to be produced from the pollen-grains, 
the author opposes the fact of the enormous number of granules 
contained in the pollen-masses ; for instance, in Orchis Morio the 
two principal pollen-masses contain each no less than 200 secon- 
dary masses ; and the latter, which when compressed divide into 
granules united in fours, individually present more than 300 
orifices from which pollen-tubes may be emitted; consequently 
in all no less than 120,000 tubes may be produced. Again, in 
Orchis abortiva the moistened point of a needle will take up 
several thousand of the simple spherical pollen-grains, and in 
this species the progress of the pollen-tubes along the conducting 
tissue of the female organ may be easily followed, affording con- 
viction that the mucous cords are neither more nor less than 
prolongations of them. 
With regard to changes of relative position of the parts of the 
ovule in the ovary occurring before the period of fertilization, the 
author does not consider it worth while in the present day to 
stop to discuss them, since it is known that in whatever direction 
the orifices of the coats of the ovule point, the ovules may be fer- 
tilized by filaments floating freely in the cavity of the ovar}\ He 
notices that M. Brongniart found instances of this in Helian- 
themum niloticum and cegyptiacum, without however recognizing 
the free filaments to be pollen-tubes ; and he himself has seen 
similar filaments free in the ovary of Cresta gialla^, which pos- 
sesses no conducting tissue. 
The first researches of Professor Amici on the Orchidacece were 
made on Orchis Morio. At the period when the corolla expands, 
the ovule is so far developed, that the testa, the tegmen and the 
nucleus, or the primine, secundine and nucleus, may be distin- 
guished ; the latter consists of a large central utricle inclosed in 
a laver of smaller cells; it resembles an acorn, the teguments 
representing the cupule. 
Subsequently this cellular layer or membrane which clothes the 
nucleus opens like a tulip, and the nucleus, consisting of a simple 
cell, remains wholly uncovered, so that a granular fluid collected 
toward the apex may be seen in its interior. It might be sup- 
posed that this exposure of the nucleus indicates the fitting mo- 
ment for fertilization, but this is yet far distant. 
When the flower has begun to wither, a new transformation 
has taken place in the ovule. The testa and tegmen have in- 
* Cresta giaJIa is translated Cockscomb, with a query, by Prof. Von Mobl. 
In the Ann. dcs Sc. Nat. it is considered as Rhinanthus crista gaUi. It 
seems most probable that Celosia cristata is the plant in question. — Rep. 
