1916 CURRENT LITERATURE 247 
Orthogenetic saltation—-BENEDICT“’ has undertaken a study of the 
genetic). It seems that ~_ this fern there have arisen more than 100 forms 
in less than 15 years. The present paper is concerned chiefly with a record of 
the facts. Uniform and highly developed cultural conditions are thought to 
favor the preservation of variations which under wild conditions would be 
eliminated. 
The variations are classified as progressive and regressive, implying in 
the one case increasing departure from the parent form and in the other 
case a return toward the parent form. Progressive variations have appeared 
along three main lines: (1) increasing division of the leaf, observed through 
5 vegetative generations; (2) increasing ruffling of the pinnae, observed 
a 
Regressive variations rarely if ever show a complete return to the parent form 
The coefficient of variation for thot variations is very low, probably 
between 1:1,000,000 and 1:1,000; while regressive variation is much more 
common. The variations are all seaeiebos and the differences are said to 
be as great as those existing between many wild species of ferns. The main 
difference between these variations and those shown by wild forms is that the 
former do not survive natural conditions, the variation usually being accom- 
paniéd by diminished vigor.—J. M. C. 
Anomalous endosperm and the problem of bud sports.—EMERSON® has 
recorded some new and interesting cases of hybrid maize kernels in which half 
of the endosperm shows a different combination of Mendelian characters from 
the other half, although it is obvious, from the fact that both parts show xenia, 
that the endosperm as a whole is due to double fertilization. He discusses 
two hypotheses, either of which might account for such ee wi 
East and Hayes’ hypothesis of somatic segregation and his own hypothes 
of somatic mutation. A third, suggested years ago by CouLTER and uate: 
nor mutation, in the sense in which EMERSON obviously uses the latter term 
™ BENEDICT, R. C., The origin of new varieties of Nephrolepis by orthogenetic 
saltation. I. Progressive variations. Bull. Torr. Bot. Club 43:207~234. pls. 10-15. 
1916. 
*s EMERSON, R. A., Anomalous endosperm development in maize and the problem 
of bud aaa Gaaae Ind. Abstamm. u. Vererb. 14:241-259. 1915. 
