224 BOTANICAL GAZETTE [SEPreMgen — 
GUILLIERMOND® has published a second paper upon nuclear and cell division 
in the ascus, extending his observations to Pustularia vesiculosa, Peziza colin, 
Ascobolus marginatus, and Peziza rutilans. For the first three he finds that the 
nuclear figures agree with what he and others have already described for other 
forms. P. rutilans possesses unusually large nuclei and differs from other foms 
so far studied in that the nuclear membrane disappears during mitosis; neither 
centrosomes nor asters are in evidence. In contradiction to DANGEARD’s gener 
ization that the Ascomycetes have four chromosomes, GUILLIERMOND finds eight 
in Aleuria cerea, P. vesiculosa, and probably also in Otidea onotica; twelve in 
P. cotinus, and sixteen in P. rutilans—W. G. MARQUETTE. 
Morrrer®? has studied the development of the sperm in Chara fragilis, his 
account differing in certain important details from that of Belajeff. The ble- 
pharoplast is crescentic in cross-section, being concave within, and is of home 
geneous structure, excepting a strip of granular substance along the concave side 
at the posterior end. It arises as a delicate thread-like differentiation of the 
cytoplasm at the surface of the cell, seeming to be a modification of the plasm 
membrane, and in its later stages is one piece, extending the entire length of the 
sperm. The cilia were always found attached some distance back of the antenor 
extremity of the blepharoplast, and did not seem to develop from any centrosome 
ike body or “Plasmahicker,” as described by BELAJEFF, STRASBURGER, ani 
others.—J. M. C. f 
PARTHENOGENESIS in Taraxacum officinale was reported about a year ag 
by Raunkraer,™ but the evidence was hardly convincing. Ina short prelimi 
nary announcement JuEL’? describes the tetrad formation in the ovule. Te 
embryo sac mother-cell divides, giving rise to two cells of unequal size.” 
smaller cell, which is nearer the micropyle, disorganizes without further — 
while the larger cell develops at once into an apparently normal embryo 
Although the number of chromosomes was not determined definitely, 
to be no reduction, between 20 and 30 chromosomes appearing in both the mother 
sac mother-cell and in vegetative cells. The mitosis in the embryo sac 
cell is not heterotypic, although in some phases it resembles this form. CH! 
J. Coampertam. : 
Pp ‘ ibed by OveRTON” 
ARTHENOGENESIS in Thalictrum purpurascens was descri shat 
1902." A preliminary announcement'+ of his further studles shows 
z les Ascomyee 
9 GUILLIERMOND, M. A., Recherches sur la karyokinese chez 
Rev. Gén. Bot. 16: 129-000. 1904. oe a Annals 
t© Mortier, D. M., The development of the spermatoz oid io AES 
Botany 18: 245-254. pl. 17. 1904. 
** See Bor. Gaz. 36: 397. 1903. Taraxacum- Arkit 
12 JuEL, H. O., Die Tetradenteilung in der Samenanlage von 
Bot. K. Svenska Vetensk. Akad. 2:— (reprint pp. 9)- 1904- 
*3 Bor. Gaz. 33: 363-375. 1902. 
: 4 OVERTON, J. B., Ueber Parthenogenesis bei Thalictrum 
laufige Mittei 
pur purasens. (SS 
lung.) Ber. Deutsch. Bot. Gesells. 22: 274-283. pl. 15- aid 
