304 BOTANICAL GAZETTE [APRIL 
orient himself with the least possible expenditure of time and effort in the impor- 
tant fields which have been opened up by MENDEL and his belated successors. 
EMERSON® gives a continuation of his studies in bean hybrids, in which he 
now treats his results statistically, instead of qualitatively as in his preliminary 
report two years ago. e numbers are mostly not large, but considering the 
smallness their agreement with the theoretical ratios is fairly close. The chief 
interest in EMERSON’s results is the class of characters investigated, often making 
classification difficult, and considerable error probably being introduced in this 
way. A few of these characters with the dominant member of the pair given first 
are as follows: running habit (flowers axillary), bush habit (flowers terminal); 
pods tender, pods tough; pods green, pods yellow. In the case of stringless vs. 
stringy pods, about half the crosses showed the former dominant, the other half 
being intermediate; though all the progeny from any given cross behaved con- 
sistently. EMERSON shows that no prediction can be made regarding the hered- 
itary behavior of seed-color from knowing the relations obtaining in other hybrids 
having the same seed-color, a fact also noted by TsCHERMAK in the first paper 
mentioned above. 
Correns’? has reported the results of further observations on hybrids of 
Hyoscyamus niger, H. pallidus, and H. major. The former crossed with its var. 
annuus shows complete dominance of the biennial habit with typical splitting in 
F, and later generations. H. pallidus x H. niger, which was reported in a pre- 
vious paper as giving intermediate flower color in F,, isnow shown to split typically 
in later generations, regardless of the annual or biennial habit of the offspring 
and independently of evironmental conditions. : 
ORRENS" has also investigated the hereditary relations of gynodioecism, 
dealing chiefly with Satureja hortensis and Silene inflata. In the former species 
bisporangiate flowers crossed together showed a predominance of bisporangiate 
plants in F,, but when stigmas of the ovulate plants were pollinated with pollen 
from bisporangiate plants the ofispring were almost without exception ovulate. 
In Silene the results were very similar, ¢X¥% giving almost entirely °, and #X% 
resulting in a predominance of ¢. This is quite contrary to Mendelian — 
tion, and the author does not believe that sexuality can be aligned under ordinary 
laws governing characters of hybrids, which it will be recalled has been attempted 
by CasTLe*? with reference to animals.—G. H. SHULL. 
9 EMERson, R. A., Heredity in bean hybrids. Ann. Rept. Agr: Exp. Sta. 
Nebraska 17: 33-68. 1904. 
t° CorRENS, C., Ein typisch spaltender Bastard zwischen einer einjahrigen SIppe 
des Hyoscyamus niger. Ber. Deutsch. Bot. Gesells. 22:517-524- 1994: 
: LG f. 
™ CoRRENS, C., Experimentelle Untersuchungen iiber die Gynodioecie. sa 
Deutsch. Bot. Gesells. 22: 506-517. 1904. 
7-218. 
12 CASTLE, W. E., The heredity of sex. Bull. Mus. Comp. Zool. 40:18 
1903. 
