24 
cross. Sargent speaks of their reverting 
to Kaempfer’s species in flower color. 
It is of course to be expected that they 
will show segregation. It is quite 
possible that something in the way of a 
new catalpa of value can be fixed from 
this cross. It would be a matter of grow- 
ing a large number of seedlings and 
selecting for several generations. The 
trees flower young, so that this would 
not be as hopelessly slow a proposition 
as with most trees. Since the history of 
many valuable plants points clearly to 
their hybrid beginnings, it seems well 
worth continuing this hybrid into later 
generations. The likelihood of obtaining 
anything of value would depend largely 
upon the number of trees grown. For 
this reason the Connecticut Station 
would be glad to furnish almost any 
quantities of seed from the first crossed 
plants, which would give the segregating 
generation, to anyone who would be 
interested in growing them. The trees 
require little attention after they are 
once started, and in many places catalpa 
growing has proven to be a -profitable 
commercial venture. The segregating 
generation would not give as uniform a 
tree as the pure species and probably 
The Journal of Heredity 
would not be so profitable to grow, but 
might ultimately produce a new tree of 
real merit. In view of the results secured 
from this cross, other crosses of these 
two species with C. speciosa would be 
worth trying. 
Since the hybrid artificially produced 
from C. bignonioides and C. Kaempferi 
coincides with the natural hybrid de- 
scribed under the name of ‘Teas’ 
hybrid catalpa,” and therefore confirms 
its assumed parentage, this fact lends 
considerable probability to other cases 
of hybrid trees whose ancestry can be 
no more than guessed at by a compari- 
son of the characters of the new form 
with its possible parent species. 
As an illustration of hybrid vigor, 
it is one more to be added to the long 
list of augmentations of growth imme- 
diately resulting from crossing. In 
this case it is particularly easy to see 
how many superficial features have 
been contributed by both parents, and 
this may be taken as one indication that 
the greater size and hardiness possessed 
by the hybrid is similarly due to the 
combined action of favorable growth 
factors contributed by compatible but 
diverse parents. 
LECTURES ON HEREDITY AND 
SEX (delivered in Glasgow, 1917- 
18), by F. O. Bower, J. Graham 
Kerr, and W. E. Agar Pp. 119, 
with 46 illustrations. London: Mac- 
millan & Co., Ltd., 1919. 
The authors announce that they have 
tried “to convey in as simple terms as 
possible the leading facts relating to 
Sex in Animals and Plants, together 
with suggestions bearing on the use and 
effect of sexual propagation.” The 
evolution of sex is taken up at some 
length. Heredity is disposed of in a 
conventional manner with a brief ac- 
count of Mendelism and a more ex- 
tended discussion of correlations be- 
tween parent and offspring. The book 
contains many sound suggestions, but 
is probably too detailed and technical 
for the ordinary reader, while for the 
serious student the absence of refe1- 
ences will be a drawback.—P. P. 
William 
The 
SEX CONTROL, by John 
Conway. Pp. 118. Kansas: 
Norton Champion, 1919. 
Mr. Conway, who is apparently not 
familiar with the large amount of care- 
ful work that has been done during 
recent years on the problem of sex. 
control, has brought together a con- 
fused mass of information, which he 
first published in his local weekly news- 
paper. The two tangible theories 
which he espouses are the time-honored 
ones that (1) the offspring is of the 
sex of the weaker or less passionate 
parent, and (2) that the offspring is 
of the sex of that parent which is best 
nourished. Mr. Conway makes no at- 
tempt to reconcile the contradictions of 
these two theories, and he also drags 
in prepotency, atavism, and various 
other more or less mystical ideas, to 
complicate the situation still further. 
No new evidence of value is included 
in support of his thesis—P. P. 
