Ocroser 4, 1918] 
excusable even on the plea of pedagogical 
necessity. For example in the treatment of 
Mendel’s pea hybrids the “ wrinkled-smooth ” 
seed character is given as similar in time of 
expression to the “ tall-dwarf ” plant character 
which in inheritance is one generation later 
in its apparent effect so that the statement 
that first generation dihybrid plants will all 
be tall and smooth-seeded individuals would be 
quite confusing to the beginning student if 
he repeated such an experiment for himself. 
For the purpose of illustrating the behavior 
of a dihybrid it serves the authors’ purpose 
but there is certainly no lack of material 
which could be used equally well to illustrate 
this point without alteration ‘of the actual 
facts. 
The work of East, Shull, Emerson, Blakeslee 
and many others is freely drawn upon in 
bringing out the different phases of the sub- 
ject. The chapters of chief interest to the 
geneticist are those on Parthenogenesis and 
Vegetative Apogamy, Inheritance in Gameto- 
phytes, and the Endosperm in Inheritance. 
A number of facts in regard to sex determin- 
ation in plants have been gathered together. 
All these subjects have usually been scantily 
treated in books on genetics. 
In the opinion of the writer the authors 
were not wise in including the complex sub- 
ject of sterility in an’ elementary book of this 
kind especially as it is treated in the chapter 
on self-sterility. The beginning of the chap- 
ter emphasizes the importance of self-sterility 
as a means of insuring cross-pollination while 
the remainder is largely devoted to Belling’s 
work on semi-sterility which has no signifi- 
cance in this connection. No clear distinction 
is made between the different types of sterility 
which would seem desirable if the subject is 
to be discussed at all. A chapter is devoted 
to the subject of hybrid vigor and the book 
closes with an able summary of the theoretical 
points involved in a consideration of the 
chromosomes as the bearers of the hereditary 
determiners. 
Throughout there is shown a first-hand un- 
familiarity with the genetical experiments dis- 
eussed. In spite of this handicap a really 
SCIENCE 
347 
useful book, for those not primarily interested 
in genetics, has been produced which shows 
the authors’ ability to coordinate many differ- 
ent, specialized fields of investigation and to 
put the results into an easily read form. The 
book is designed to fill an important place 
which would justify more care in the choice 
of material and in its presentation. The prac- 
tise followed of giving few facts and discuss- 
ing them in all their important relations. to 
each other and to other fields of biology is 
perhaps the most valuable feature of the book. 
D. F. Jones 
CoNNECTICUT AGRICULTURAL EXPERIMENT STA., 
New Haven, Conn. 
THE POWER SITUATION IN THE 
UNITED STATES 
Two of the most important domestic prob- 
lems facing the United States at the present 
time concern the supply of power necessary to 
maintain the industrial activities of the coun- 
try, and the adequacy of transportation to 
move the raw materials and finished products 
involved in these activities. As the coal con- 
sumed in the United States engages over a 
third of the freight capacity of our railroads, 
and more and more coal is being used, the re- 
sult is a growing burden upon transportation 
which must be relieved. The power problem 
and the transportation problem, therefore, are 
really different expressions of a single funda- 
mental issue. In this connection the United 
States National Museum, Smithsonian Insti- 
tution, has just issued a 50-page Bulletin, en- 
titled “Power: Its Significance and Needs,” 
which gives an analysis of the whole situation 
and presents a plan whereby the problems of 
water-power, coal-supply, and transportation 
may find a solution. This contribution is by 
Chester G. Gilbert and Joseph E. Pogue, of 
the Division of Mineral Technology, and is 
Part 5 of Bulletin No. 102, the Mineral Indus- 
tries of the United States, which has already 
dealt constructively with such matters as coal- 
products, fertilizers, domestic fuel and pe- 
troleum. 
Quoting from the conclusions of the authors 
of this Bulletin, it is stated: 
