320 BOTANICAL GAZETTE [OCTOBER 
bers of a pair may separate at this stage. Tetrads sometimes occur at this 
time. The mantle fibers (Zugfasern) are believed to persist from one cell 
generation to another. The nuclear membrane is a tonoplast, and the nuclear 
cavity a complex of vacuoles. 
Many of the figures look rather diagrammatic, but they are carefully 
drawn, and the summary indicates that the author, at least, feels certain of 
his principal conclusions, The work is so extensive and so well presented that 
it cannot be laid aside; cytologists should either confirm the conclusions or 
correct them.—CHARLES J. CHAMBERLAIN 
Fungi in rhizoids of liverworts.—Investigation of about thirty species of 
liverworts by GARJEANE’ shows that there is no uniformity in the occurrence 
of fungi in the rhizoids. In some forms the presence of fungi seems to be the 
growth of the hyphae are described for Lophozia inflata and species of Cephalo- 
zia and Cephaloziella. From the details it appears that the plants in no way 
profit as a result of the presence of fungi in their rhizoids. On the contrary, 
the protoplasm in the young rhizoids, and also in the neighboring cells when 
these are infected, is killed by the fungi. Extended infection of rhizoids is 
accompanied by sickening of the plants. An interesting reaction of the 
thizoids to the attack of the fungus is described ‘in Lephozia. When the 
hypha comes into contact with a rhizoid, a thickening appears on the inside 
of the rhizoid wall opposite the point of contact. As the hypha grows:into the 
cell, cellulose is continually deposited ahead of the growing point, so that the 
hypha is surrounded by a sheath of cellulose. Often hyphae pass straight 
through rhizoids in this way, and become incased in a tube of cellulose. The 
author was successful in isolating the same species of fungus, described as 
Mucor rhizophilus, from nine species of liverworts. A large number of suc- 
cessful infections was made with this fungus in sterile cultures of Lophozia 
inflata, Cephalozia anata Cephaloziella sp., and Jungermannia ventri- 
cosa. The author believes that the association of fungus and rhizoid is not 
of the nature of a caedes: neither does the fungus cause considerable 
damage to the plant, although strongly infected plants show the unfavorable 
influence of the fungus.—H. HassELBRING. 
Fall of petals.—Firrinc’ finds that a number of stimuli will cause the pre- 
mature falling of the corollas of various sympetalous and polypetalous flowers. 
He worked in the main, however, with Geranium pyrenaicum. Among chemi- 
7Garjeane, A. J. M., Die Verpilzung der Lebermoosrhizoiden. Flora 102: 
148-185. pls. 11, 12. figs. 9. 1911. 
* Firrinc, Hans, Untersuchungen iiber die vorzeitige Entblatterung von Bliiten. 
Jahrb. Wiss. Bot. 49:187-263. 1911 
