different
from what it used to be. The pale and leaden faces are scarcely seen in
the wards; the expression of the children is brighter and more lively."
Adult patients have described the relief afforded by inoculation; it
acts like a charm, and lifts the deadly feeling of oppression off like a
cloud in the course of a few hours. Finally, the counteracting effect of
antitoxin in preventing the disintegrating action of the diphtheritic
toxin on the nervous tissues has been demonstrated pathologically. There
are some who still affect scepticism as to the value of this drug. They
cannot be acquainted with the evidence, for if the efficacy of antitoxin
in the treatment of diphtheria has not been proved, then neither can the
efficacy of any treatment for anything be said to be proved.
Prophylactic properties are also claimed for the serum; but protection
is necessarily more difficult to demonstrate than cure, and though there
is some evidence to support the claim, it has not been fully made out.

AUTHORITIES.--Adams, _Public Health_, vol. vii.; Thorne Thorne,
_Milroy Lectures_ (1891); Newsholme, _Epidemic Diphtheria_; W. R.
Smith, _Harben Lectures_ (1899); Murphy, _Report to London County
Council_ (1894); Sims Woodhead, _Report to Metropolitan Asylums Board_
(1901).

DIPLODOCUS, a gigantic extinct land reptile discovered in rocks of Upper
Jurassic age in western North America, the best-known example of a
Sauropodous Dinosaur. The first scattered remains of a skeleton were
found in 1877 by Prof. S.W. Williston near Canon City, Colorado; and the
tail and hind-limb of this specimen were described in the following year
by Prof. O.C. Marsh. He noticed that in the part of the tail which
dragged on the ground, each chevron bone below the vertebral column
consisted of a pair of bars; and as so peculiar an arrangement for the
protection of the artery and vein beneath the tail had not previously
been observed in any animal, he proposed the name _Diplodocus_ ("double
beam" or "double bar") for the new reptile, adding the specific name
_longus_ in allusion to the elongated shape of the tail vertebrae. In
1884 Prof. Marsh described the head, vertebrae and pelvis of the same
skeleton, which is now in the National Museum, Washington. In 1897 the
next important specimen, a tail associated with other fragments,
apparently of _Diplodocus longus_, was obtained by the American Museum
of Natural History, New York, from Como Bluf