1904] DAVIS—SEXUAL ORGANS IN PLANTS 263 
gia are multicellular organs which develop uninucleate gametes, 
These are believed to be derived from zoosporangia, multicellular structures 
which form zoospores. According to the author’s hypothesis (Davis ’o3¢) the 
gametangia of groups of extinct Chlorophyceae leading into the bryophytes 
became differentiated into 
Spermatangia (anther'dia), multicellular organs developing sperms, and 
Oangia (archegonia), multicellular organs developing eggs. 
Coenogametes are multinucleate sexual cells, and are morphologically either 
gametocysts that have become changed directly into gametes, or they are restricted 
portions of such cells. In the Mucorales and Gymnoasceae the coenogamete con- 
tains all of the protoplasm of the parent cell. In the Peronosporales and certain 
Ascomycetes only a portion of the protoplasm of the gametocyst is utilized in the 
gamete, the superfluous protoplasm passing into sterile structures (periplasm, 
conjugating tubes, sterile cells, etc.). The sexual organs of these latter forms, 
which are probably higher conditions than the former, may very properly retain 
the old names of oogonium, ascogonium, and antheridium. The structure of the 
sexual organs of the lichens and the Laboulbeniaceae is not sufficiently known 
to establish their position in this classification. 
THE UNIvERsiry OF CHICAGO. 
LITERATURE CITED. 
Barker ’03, The morphology and development of the ascocarp in Monascus. 
Ann. Botany 17:167. 1903. 
Zur Frage nach der Sexualitit der Collemaceae. Ber. Deutsch. Bot. 
Gesells. 16: 363. 1898 
ott 8, Die Anlage und Entwickelung einiger Flechtenapothecien. Flora 
D +319. Igor. 
aoe °3, Observations on Gymnoasceae. Ann. Botany 1'7:571. 1903. 
? . Mf 
ARBISHIRE ’00, Ueber e Apothecienentwickelung der Flechte Physcia pul- 
verulenta 
Davis ’00, 3 ly 
7a ’or, 
se ab The evolution of sex in plants. Pop. Sci. Monthly 62: 300. 1903. 
’o4, Oogenesis in Vaucheria. Bor. Gaz. 38:81. 1904. 
licher ane Homologien in der Entwickelung miannlicher und weib- 
; hlechtsorgane. Flora 90:279. 1902. 
: he Entwickelung des Peritheciums bei Sphaerotheca Castagnei. 
og Ves Gls 28S 95 joe 
erne bei der Fruchtentwickelung einiger 
Ascomyceten. Jarhb. Wiss. Bot. 29:655. 1898. 
