740 General Notes. [ September, 
Tue TaiL IN THE Human Empryo.—This is a subject of con- 
siderable interest in view of the occasional statements regarding 
tailed races of men in the interior of Africa, and of the supposition 
that the human embryo has a tail homologous with that of the 
monkeys, and that, therefore, in this respect, man passes through 
a monkey-stage, as insisted upon by Haeckel, who remarks in his 
“History of Creation,” Vol. 1, p. 308, “‘ Now, man in the first months 
of development possesses a real tail as well as his nearest kindred, 
the tailless apes (orang-outang, chimpanzee, gorilla), and verte- 
brate animals in general. But, whereas, in most of them—for ex- 
ample the dog, it always grows longer, in man and in: tailless 
mammals, at a certain period of development, it degenerates and 
finally completely disappears. However, even in fully developed 
men, the remnant of the tail is seen in the three, four or five tail 
vertebrz (vertebrae coccygae) as an aborted or rudimentary or- 
gan, which forms the hinder or lower end of the vertebral col- 
umn.” Now this notion is rudely disputed by Professor His, who 
contradicts in a paper on this question (abstracted in the Jour- 
nal of the Royal Microscopical Society) the assertion that at 4 
certain stage in its development the human embryo has a true 
tail, which is afterwards absorbed. As to the definition of a tail, 
Professor His considers that the caudiform or tail-like prolongation 
is a true tail when, extending beyond the cloaca, it contains a 
number, greater or less, of supernumerary vertebre. Without 
‘this condition there is merely a caudiform appendage. His knows 
of no well-authenticated case of supernumerary vertebr@ in the 
human embryo, and pathological observation he believes to co!m- 
cide with embryological knowledge in justifying the assertion 
that in man the normal number of thirty-four vertebra is never 
exceeded. 
Prof. His’ paper appeared in 1880; the same year, however, Dr. 
Leo Gerlach published in Gegenbaur’s Morphologisches Jahrbuch 
(Band vi, Heft. 1.) a paper on a case of tail-formation in a uman 
embryo. He refers to a case of the occurrence of a tail in an ab- 
normal embryo described in 1840 by Dr. Fleischman. On holding 
the foetus up to the light there appeared, in the first third ts 
whi 
nd of 
this tail seemed to be skinny, and was very delicate and transp?” 
rent. This embryo forms the subject of Gerlach’s exhaustive 
anatomical account before us. The embryo is 10. 
(four inches) long and was in the early part of the fo 
of embryonic life. The free portion of the tail is 12 
it is long and slender, being in length equal to that o 
the embryo. In this tail a well-marked notochord is present. 
organ, therefore, should be regarded as the homologue of a ae 
uine tail, and Gerlach considers it as a case of atavism, and that zs 
represents an earlier phylogenetic condition. He thinks, for rea | 
