514 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
classes of animals ; in tlie latter case, its importance consists in its 
greatly intensifying the segregative power of whatever other form of 
isolation it may be with which it is associated.” 
Law of Heredity.* — Mr. Francis Galton has investigated in regard 
to Basset blood-hounds the average contribution of each several ancestor 
to the total heritage of the offspring. The result is to verify in this 
instance the statistical law of heredity which was stated in ‘ Natural 
Inheritance’ (1889). The law is that the two parents contribute be- 
tween them on the average one-half (0 • 5) of the total heritage of the 
offspring ; the four grandparents, one-quarter (0 • 5) 2 ; the eight great- 
grandparents, one-eighth (0*5) 3 , and so on. Thus the sum of the ances- 
tral contributions is expressed by the series {(0*5) -f- (0*5) 2 -f- (0*5) 3 , 
&c. J, which, being equal to one, accounts for the whole heritage. The 
same statement may be put in another form : — that the occupier of each 
ancestral place in the nth degree, whatever bo the value of n, contributes 
(0 * 5) 2 ” of the heritage. 
Influence of a Previous Sire.f — Dr. A. S. Bell reviews some of the 
old cases of supposed Telegony, and criticises the two explanatory 
theories — (a) that the sperm of the first sire affects unripe ova in the 
ovary, and ( b ) that an influence saturates from the foetus to the mother, 
and through her affects future progeny. Dr. Bell also gives the results 
of various experiments and observations he has made as to dogs, horses, 
and pigeons. None of these in any way suggested the occurrence of 
Telegony. He also narrates the case of a woman who bore a male 
child, an ordinary mulatto, to a pure negro, and two years and nine 
months later bore a female child to a white man. This second offspring, 
now a woman, shows no trace of negro blood. 
Regeneration of Tail in Lizards, t — Dr. F. Werner has made a 
study of this interesting phenomenon in a large number of lizards, in- 
cluding representatives of twelve families. He begins by noting that 
very many reptiles are without the power of regenerating the tail, e.g. 
crocodiles, tortoises, snakes, chameleons, Varanidse, Heloderma, and 
Amphisbenide. In some cases of lizards, the regenerated tail has the 
same scaling as the original tail, viz., Lacertidae, Gerrhosauride, Tejide, 
Zonuridae, Uroplatide, Anniellidae, and finally, Sphenodon , in which the 
regeneration is remarkably exact. In other cases, with which the author 
is chiefly concerned, the scaling of the regenerated tail is different from 
that of the original. His general conclusions as to the last set of cases 
are as follow. The more primitive characters are regenerated, the pre- 
sumably newer differentiations tend to be suppressed. The original 
segmentation of the scaling, the occurrence of preformed rupture-lines, 
and the differentiation of a vertebral column, are suppressed in regenera- 
tion. Where the scaling of the primary tail-end is different from that 
of the rest of the tail, the secondary tail resembles the primary tail-end. 
Those differentiations which are not regenerated are late in appearing 
in the embryos. The regeneration of the tail is most exceptional, or is 
at least limited, when the tail has an adaptive differentiation as a 
* Proc. Roy. Soc., lxi. (1897) pp. 401-13. 
t Journ. Anat. Physiol., xxx. (1896) pp. 258-84. 
X SB. K. Akad. Wiss. Wien, cv. (1897) pp. 123-46 (2 pis.). 
