1904] DAVIS—OOGENESIS IN VAUCHERIA 97 
of the nucleus with numerous small granules on a delicate linin 
network. 
After fertilization the nucleus of the sperm passes to the center of 
the egg, where it increases in size at the side of the female nucleus in 
the same region of dense protoplasm. The two sexual nuclei fuse 
slowly when both are approximately of the same size. 
THE UNIVERSITY OF CHICASO. 
LITERATURE CITED. 
BEHRENS ’90: Einige Beobachtungen tiber die Entwickelung des Oogons und 
der Oosphire von Vaucheria. Ber. Deutsch. Bot. Gesells. 8:341. 1890. 
Davis ’03: Oogenesis in Saprolegnia. Bor. Gaz. 35:233 and 320. 1903. 
GOLENKIN ’99: Ueber die Befruchtung bei Sphaeroplea annulina bad iiber die 
Structure der Zellkerne bei einigen griinen Algen. Bull. Soc. Imp. Nat. 
Moskow 343. 1899 
HarPER ’g9: Cell division in sporangia and asci. Annals of Botany 13: 467. 
99- 
KING ’03: Observations on the sty sae! of Araiospora pulchra Thaxter. Proc. 
Boston Soc. Nat. Hist. 31:211. 1903 
KLEBAHN ’92: Die Befruchtung von Ondoswaein Boscti. Jahrb. Wiss. Bot. 
24:235. 1892. 
KLEBAHN ’99: Die Befruchtung von Sphaeroplea annulina Ag. Festschrift fir 
Schwendener 81. 1899. 
LAGERHEIM ’oo: Untersuchungen tiber die nominees Bihang Svenska 
Vet.-Akad. Hand. 25:Afd. 3, no. 8. 
OLTMANNS ’95: Ueber die Pane ae a“ es bei Vaucheria. Flora 
80: 388. 1895 
ROSENBERG ’03: Ueber die Befruchtung von oe alpina (Johans.). Bihang 
Svenska Vet.-Akad. Hand. 28:Afd. 3, no. 1903. 
RUHLAND ’03: Studien iiber die od ated ie ‘Aiace Lepigoni und einiger 
Peronsporeen. wie Wiss. Bot. 39: 3: 
SWINGLE ’03: Formation of the spores in ee sporangia of Rhizopus nigricans 
and of Mieco. nitens. U. S. Dept. Agric. Bur. PI. jae Bull. 37. 
1903. 
EXPLANATION OF PLATES VI AND VII. 
The sections were cut 5 thick and stained with safranin and gentian violet. 
All figures were sketched with an Abbé camera under the Zeiss apochromatic 
objectives 2™™ or 1.5™™ in combination with compensation oculars. e mag- 
nification is as follows: figs. 1-2, X 500; figs. 3-8 and 10-13, x 667; fig. 9, X 2,000; 
fig. 14, X1,334- 
