156 DEVELOPMENT OF THE OVULUM 
He describes it as he did in his former paper, and adds 
that it is only when the embryo commences that the quintine 
swells into a cellular mass, either transparent and mem- 
branous or opaque and fleshy, this swelling almost always 
takes place from above downwards. 
He says that when the chalazal appendix exists the quin- 
tine is attached to its apex, that the development of both is 
simultaneous. 
It would appear likewise that in some cases the embryo is 
developed outside the quintine, as in Statice, for we are told 
p. 55, that the albumen is developed in the quartine, such a 
structure is so contrary to all analogy, that I have little hesi- 
tation in saying tbat if this quintine be not quartine, it is a 
mere modification of the stalk of the embryo. 
In the instance of Cicer arietinum figured to shew the 
quintine, there is enough to raise a suspicion that it is the 
embryonary sac in an early stage, at least it agrees with this 
sac in situation and appearance. 
Embryonary sac, Amnios, Quartine. 
This name which is very appropriate, originated with M. 
Brongniart, who rightly supposed that the embryo was 
formed in it in almost all cases. M. Brongniart, however, 
confines its application to the ovulum; subsequently however, 
if I understand him rightly, he supposes that the embryo in 
most other plants (he is speaking of Ceratophyllum) is not 
actually contained within the sac, but that the sac and the 
embryo have the same relations that our viscera are suppos- 
ed to have to our peritonea ? 
This sac, to which the name embryonary is most aplica- 
ble, since in it the embryo is invariably developed, com- 
mences as I have stated in the shape of a vesicle. It is 
situated generally at that part of the nucleary excavation 
which corresponds to the apex of this organ, but in some it 
is developed from the opposite point. It is the only essential 
part of an ovulum antecedent to the apperance of the em- 
_bryo. This assertion I consider justified by the consider- 
ation of Santalum and of Viscum. 
