Feb., 1908.] Polar Conjugation in the Angiosperms. 
2 55 
type. Other teleosts in which the gustatory system is reduced as 
compared with Ameiurus, as well as Cyclostomes, Elasmobranchs 
and Amphibia must be studied with this particular point in view. 
In other forms the neural crest element is apparently fairly 
constant in those nerves which contain gustatory fibres. The 
small size of the special visceral component and of the placodes 
in these types may account for the idea that the placodes arise in 
response to the stimulus furnished by the contact of the neural 
crest with the skin. The catfishes, however, are unique in the 
size of their placodes and of their special visceral component. 
And if the IX ganglion should prove not to be a pure placodal 
ganglion and the IX nerve of the adult does supply general 
visceral surfaces, I still think the evidence very strong that the 
placodal portions of these ganglia give rise to the special visceral 
or gustatory fibres. 
And the special visceral system bears the same relation to the 
general visceral that the Acustico-lateralis system bears to the 
general cutaneous. 
ON THE ORIGIN OF POLAR CONJUGATION IN THE 
ANGIOSPERMS. 
John H. Schaffner. 
Various attempts have been made to explain the probable 
origin of the remarkable structures and activities present in the 
embryosac of the Angiosperms. These attempts, however, 
resulted in mere hypotheses with few or no known facts in their 
favor to recommend them for serious consideration. With the 
recent great advance in our knowledge of the female gametophyte 
of the Gymnosperms, due to the thorough work of a number 
of zealous observers, has come the opportunity for a reconsid¬ 
eration of the problem in the light of the new discoveries. Porsch 1 
has done this in a very interesting and convincing paper in which 
he presents very strong evidence for his views. 
He holds that the two synergids of the Angiosperms are neck 
canal cells homologous with the neck canal cells of the Gymno- 
sperm archegonium; that the oospheres of Gymnosperms and 
Angiosperms are homologous cells: and that the upper polar, 
which is a sister cell of the oosphere, as determined by various 
observers for different plants and very definitely by the writer 
for Erythronium, 2 is the homologne of the ventral "canal cell of 
the Gymnosperm archegonium. He holds further that the 
1 Porsch, Otto. Versuch einer phylogenetischen Erklarung des Embryosackes und der 
doppelten Befruchtung der Angiospermen. Verlag von Gustav Fischer in Jena. 1907. 
2 Schafner, John H. A contribution to the Life History and Cytology of Ervthro- 
nium. Bot. Gaz. 31 : 369-387. 1901. n ° 
