1914] CURRENT LITERATURE 167 
but the split disappears temporarily before the metaphase, when it is again evi- 
dent. During late prophase and metaphase the chromosomes often show a 
distinctly paired arrangement. In telophase there is a massing at each pole, 
after which the chromosomes separate and become joined by anastomoses. 
Considerable variation in chromosome number is shown; the usual number is 
15. The nuclei occasionally show certain characters of heterotypic mitosis.— 
L. W. Swarr, 
Poison weed.—Larkspurs have always had the reputation of being poison- 
ous, but it seems that only in North America have they been important in caus- 
ing losses of stock. Marsu and his associates’ have investigated the poisoning 
due to larkspur in Colorado, and presumably the conditions are the same in 
other mountain cattle ranges of the West. The larkspurs are grouped as tall 
and low larkspurs, Delphinium Barbeyi representing the first group, and D. 
Nelsonii the latter. These forms cause the loss of a great number of cattle, 
but horses and sheep are not injured by grazing on larkspur areas; and cattle 
are not injured if prevented from grazing on such areas until the second week of 
y. The next problem is to discover the specific poison.—J. M. C. 
Xenia.—Having discovered instances of xenia in wheat, BLARINGHEM*S 
sought to determine whether the vigorous development of hybrid enbryo and 
endosperm ever causes a change in the character of the maternal tissue that 
Surrounds them. On crossing a comparatively small wheat, known as Triticum 
furgidum gentile Al. var. Normandy, with a larger type, Triticum vulgare 
lutescens hybrid no. 126 of the Hohenheim collection, 16 hybrid seeds approach- 
ing the paternal variety in size were obtained. This phenomenon is inter- 
P reted as Xenia in the original sense of the term, though it seems probable that 
t Is simply a stretching of the pericarp due to a large hybrid embryo and 
endosperm.—E. M. East. 
Artificial cell structure.—In a series of interesting experiments, W. MaGnus* 
nas Produced, from paraffin, beeswax, and other substances, various structures 
which bear a striking resemblance to cells and tissues. The paraffin, with a 
melting point of about 74° C., was poured upon mercury which had been heated 
es 78° C. and allowed to cool at room temperature. While this is only the begin- 
hg of the investigation, the writer thinks he has already shown that through 
wé action of purely physical forces structures can be produced which look like 
«. MARsH, C, Dwicut, Crawson, A. B., and Mars, Haptercn, Larkspur or 
Polson weed.” U.S, Dept. Agric., Bur.,Plant Ind., Farmer’s Bull. 531. 1913. 
. ve ae, L., L’influence du pollen visible sur l’organisme maternal; décou- 
xénie chez le blé. Bull. Soc. Bot. France 60:187-193- 1913- 
Ma: egg Anus, Werner, Uber zellenformige Selbstdifferenzierung aus fliissiger 
terie. Ber. Deutsch. Bot. Gesells. 31: 290-303. pl. 13. 1913. 
