Encyclopaedia Britannica > Volume 21, ROT-Siam

apparently different factors, but by simply lumping them
under a common name. Nor is a rationale given of the
aflirmed reversal of sex, which Schlechter and other
authorities moreover wholly deny. Despite these and
other faults and failures the work is interesting and often
suggestive, and that not only on account of its theoretic
positmn but its sanguine proposals for the practical control
The work of Busing (1883), while less speculative, is of
great importance m respect to the causes which regulate
the proportions of the sexes ; since, instead of falling back
with Darwin on the unexplained operation of natural
selection, he seeks to note the circumstances in which a
majority of one sex is profitable, and to show that
organisms have really the power to produce in such circum¬
stances a majority of one sex,—in short, that disturbances
in the proportion of the sexes bring about their own
compensation, and further supports these views by calcula¬
tion and statistical evidence.
He separates the causes determining sex into those affecting (rr\
one parent and (6) both alike. Starting with a mLority 0T0S
sex, he emphasizes the importance of delayed fertilizatioi/accent-
mg it as a fact that females late fertilized bear most males (this
corresponding in man to a scarcity of males among the lower
animals). He notes that the firstborn child is most frequently
a mak, especially among older persons, and thus explains how
aftei a war, when there is a want of males, most male children are
born. He ascribes importance to the amount of sexual intercourse
Thus, suppose a minority of females : their fertilization tends to
occur more frequently, and thus (if the general statement be
correct) they should produce a majority of their own sex • or
similarly with males. This is supported by reference to cattle-
breeding, and it is interpreted physiologically to involve that
young spermatozoa produce a majority of males.7 Suppose a great
majority of males: the chances of early fertilization o? the females
are of course great, but eggs fertilized early tend to produce
females. Or suppose conversely a great minority of males - the
chances of early fertilization are small, but old eggs tend to
produce males, and either excess will thus become compensated
Or again the more decided the minority of one sex the more
frequent the sexual activity of its individuals, the younger their
nrp ^ ®lem®nts> allfi consequently the more individuals of that sex
are produced. Busing next takes up as indirect causes equivalent
to a minority of individuals—(a) deficient nutrition • just as fre
quent copulation overstrains the genital organs the same result
may arise from the deficient nutrition of the system ; hence an ill-
fed cow yields a female to a well-fed bull and vice versa • (6) relative
age ; the nearer either parent is to the period of greatest renrodUc
tlVAsCfaPcatClty ff6 }-SS’ J16 ?illks’ is a birth of that sex probable
nutf^n iff \ng b0th PfentS he first disci*sses variations in
nutrition, although means of subsistence may decrease there is at
fiist no decrease m the number of progeny. But it is necessarv to
so^hatTn^f et-epr0dfC-t+i-0n °f1the Species from its multiplication,
so that m defective nutrition, though an animal may not reproduce
less, it will permanently multiply much less. He agrees with
SnSih-of the reProduct,ive.is most sensitive fo changes
of nutrition gives cases showing the effect of abundant nutrition
on reproductive activity, notes the influence of climate, function
withparasfteT ^gamSTf °f ^activity, like birds and insects,’
contrasted pp f ^tritive relations of the sexes are also
contrasted , since females have to give to the embryo more than
the male, they are much more dependent on food for vigour of
their siz^tc 'FurtT'^7, and he?ce tlle frequent contrast of
their p wliH ' hmtkermore, animals suit their multiplication to
. eir conditions of nutrition ; if food be abundant there is an
innumbS f fe,males’ and therefore a further increase
in number of individuals of the species ; if food, however be too
tefdJto diminish Hare pr+<?duced and the numbe1, of the species
increase pl if V"31100.tbe colmcxion above mentioned between
good harvest afrdenrb(eSP-laUy female-S) in ProsPei% a»d after a
Prices SimfnXf he rlS1ig Portion of boys during a rise of
the more^Sl ly^°r ammalS 1 the m°re f°od tbe more females> “d
nml l P ^i lf SPecies mcreases; the less food the more males,
morefenlale flapid ^ 1“rease- A§ain> Plants on good soil produce
bad il l WerS and more seed with Profit to the species; on
tend! f df flowers Preponderate, mostly perish, and the species
to disappear. The extreme case of optimum nutrition tends
to produce normal parthenogenesis (“thelytokie ”), yielding only
*, “ales, different m cause and operation from the parthenogenesis
esulting from the absence of males (“arrenotokie”).1
SEX
723
See Diising, Jena Zeitschr., 1885; Starkweather, Law of Sex, 1883.
Theory of Reproduction and Sex.—If we now at tern nf
— allr' Sf1POint fr0m Which
ble conceptions of sex,-
a reallv . Irl w^seef a ^rm l,a8'-s for the construction of
a theorv m,Th the,orr™dent that such
concerned witL l!! reSS/d n0t mereIyspecialist
but ^tne °b T 0f,reProd“cti»n “d development,
So^ike mT etailS fnd bo satis^
Jilke t0 the general morphologist and phvsio-
ofSthe mainXeV^tb0^ iiaVe bef°re US that concePtion
uP-un , 1 of bought on each of these subiects
i^Bb:zr,ined undwthe b-d^r*—
The close coincidence between these two independent
developments ,s especially to be noted. From the vaZ
tempTmmentaZh-'b™ “s'1 aPPeara'lce- of babits mid
SrvTthe’n Zn “Z6 np the descriptive natural
history of the past, the two streams of progress though
WmZand P“»ol; Thus Buff0n° furnisheda
brilliant and synthetic exposition of the oldest view, while
the handstf Ti1" generalf aspect recei^d new precision at
K Linnaeus,—to some extent the other also at the
advance ^ ^hySlol?S1Cal ^^temporaries. The anatomical
advance of Cuvier is parallel to the detailed study of the
functions of the organs, while the great step made by
Bichat lay m piercing below the conception of the organ
and its function as ultimate, and in seeking to internet
r0 k by reference to the component tissues. The cell-
theory of Schwann and his successors analysed these tissues
a step farther while the latest and deepest analysis refers
all structure ultimately to the substance called protoplasm
and similarly claims to express all function in terms of
the construction and destruction, synthesis and analysis,
anabolism and katabolism of this. See Physiology, Pboto-
plasm, Morphology.
Now, since every morphological and physiological fact or
theory is in one or other of these few categories it is
evident that we have here the required criterion of theories
of reproduction and sex. The question, What is sex? what
is meant by male or female ? admits of a regular series
of answers. The first and earliest is in terms of general
aspect, temperament, and habit, and, though crude em-
pincal, and superficial, it lacks neither unity nor usefulness
At this plane are not only most popular conceptions but
many theories like that of Starkweather, which may be
mentioned as the most recent. The anatomist contents
himself with the recognition of specific organs of sex, or at
most with a similarly empirical account of their functions •
while the embryologist and histologist will not rest con-
tented without seeking to refer these organs to the tissues
of which they are composed and the layer from which they
spring, and even reaches and describes the ultimate cellular
elements essential to sex,—the ovum and spermatozoon. A
parallel physiological interpretation of these is next required,
and at this point appear such hypotheses as these of Weis-
mann and others.
Thus the bewildering superabundance of widely dif¬
ferent theories at the present juncture becomes intelligible
enough; and, each once classified according to its stage
of progress, a detailed criticism would be easy. But this
is not enough : the demand for an explanation at once
rational and ultimate, to comprehend and underlie all the
preceding ones, is only the more urgent. Where shall we
seek for it ? On the one hand the morphological aspect of
such an explanation must interpret the forms of sex cells
in terms of those of cells in general, and in terms of the
structural properties of protoplasm itself; while its more
difficult yet more satisfying physiological aspect must
express the mysterious difference of male and female in
terms of the life processes of that protoplasm,—in terms,