1914] CURRENT LITERATURE 165 
acetic or butyric acid. The general result of the various cultures was that in 
the first case the sporelings developed normally; in the second, no sporelings 
appeared; while in the third, sporelings developed up to the 25-cell stage. The 
experiments were not carried farther. No cytological work was done. Since 
the Fucus plant is the 2x generation, it would be interesting to know the 
chromosome situation, especially if the plants should develop up to the repro- 
ductive phase.—Cnar.Es J. CHAMBERLAIN. 
Chromosome conjugation.— Miss FRASER," in a short discussion of chromo- 
some conjugation, cites the work of OVERTON, HarPER, Dicsy, and others to 
show that it is not a matter of primary importance whether parasynapsis or 
telosynapsis takes place, and that they need not be mutually exclusive. e 
sexual nuclei may fuse at once upon fertilization, or not until the division of 
the oospore in other cases (Pinaceae); while in the extreme case of the rusts 
they remain distinct until just before meiosis. In like manner the attraction 
between the homologous chromosomes may bring about their conjugation as 
soon as the nuclei fuse, or in other cases later, even as late as the formation of 
the gemini of maturation. The suggestion is made that the clearest cases of 
Mendelian inheritance will perhaps be found to be those correlated with a late 
association of the chromosomes in pairs.—L. W. SHARP. 
+ Flora of Boulder.—Dante1s” has made a study of the vascular flora of 
Boulder, Colo., and vicinity, a most interesting mountain region. An intro- 
duction (48 pp.) describes the physiography, the climate and rainfall, and the 
zones of vegetation. The zones given are Campestres, Mensales, Sul t , 
Montanae, Subalpestres, and Alpestres, each with numerous subdivisions. The 
list of plants (211 pp.) includes 1225 numbers in 486 genera, with a statement as 
to the habitat of each species. A number of new combinations are made, and 
= species described in Acomastylis (Geum), Prunus, Vitis, Castilleja, and 
Grindelia. One of the unique features of the list is that a popular name is 
8iven for each species. When this reaches such a stage as “filiform toad- 
flax-leaved painted cup,” it is probable that it ceases to be useful—J. M. C. 
Graft hybrids.—Miss Hume" has investigated three graft hybrids for con- 
uscting protoplasmic threads. The “periclinal chimaeras” used were Cytisus 
5% ami, Solanum tubi gense, and S. Kolereuterianum, since in these the epidermis 
is the only layer of cells belonging to the one component, and the line of de- 
Marcation between the two components is therefore a sharp one. BUDER 
ee 
Igr ie Faaser, H. C. L, The pairing of the chromosomes. New Phytol. 11:58-60. 
Wai, oa FRANCIS Porter, The flora of Boulder, Colorado, and vicinity. 
* “Assourl Studies. Science Series 2: no. 2. pp. xiii+311. 1911. 
oa Pian Marcaret, On the presence of connecting threads in graft hybrids. 
- 12:216-221. 1913. 
