SEPTEMBER 29, 1899.] 
the origin of the Urside back to the Oligocene. 
He places Hyznarctos, which first appears in 
the Upper Miocene, as a side line which died 
out in the Pleistocene. The Oligocene bears 
are traced back to animals related to Cynodon 
‘in the Upper Eocene and hypothetically to 
Uintacyon of North America. This paper is of 
enhanced interest in connection with the recent 
investigations of Wortman upon the origin of 
the dogs, published in a recent Bulletin of the 
Museum of Natural History, in which Uintacyon 
also figures. One feature of Dr. Schlosser’s 
paper is the complete adoption of the Osborn 
and Scott nomenclature for the cusps of the 
molar and premolar teeth. 
Dr. James P. Hitt, of the University of 
Sydney, New South Wales, has followed up his 
discovery of the allantoic placenta in Peram- 
eles by the study of the female urogenital or- 
gans in the same type. This typical bandicoot 
is found to differ wholly in the structure of 
these organs from other Marsupials. These 
differences sustain Dr. Hill’s original interpre- 
tation of the allantois of the Marsupials as 
a primitive organ characteristic of the stem 
Marsupialia, which most types have lost. To 
quote from his paper: ‘‘In concluding for the 
present this short discussion, I would remark 
that the facts here briefly set forth, in my 
opinion, show conclusively that the condition 
of the genital organ in macropods—undoubt- 
edly one of the most specialized families in 
living Marsupials—can in no sense be regarded 
as primitive, and that just in so far as the 
genital organs of Perameles depart from the 
prevalent Marsupial condition they in the same 
degree realize the more primitive type. In- 
deed, the urogenital organs of the Peramelidz 
appear, so far as I am able to judge, to have re- 
tained a more archaic condition than those of 
any other hitherto described Australian Marsu- 
pial, a conclusion which I believe gives very 
material support to that view which regards 
the existence of an allantoic placenta in the 
genus Perameles as an extremely primitive 
feature in its organization. 
UNDER the direction of the American Philo- 
sophical Society has just appeared a joint paper 
by the late Professor Baur and Dr. E. C. Case, 
SCIENCE. 
459 
entitled ‘History of the Pelycosauria, with a 
description of the genus Dimetrodon Cope.’ 
This reminds us afresh of the great loss Paleon- 
tology has sustained in this country, and in 
fact everywhere, in the death of Georg Baur. 
This memoir is a fine example of the thorough- 
ness of his work, giving us an exhaustive re- 
view of the Permian types the world over, 
which are remotely related to the living genus 
Sphenodon. This is also by far the most thor- 
ough résumé of the literature relating to the 
order termed by Cope the Pelycosauria. The 
memoir concludes by an original description of 
the great finned-back lizard Dimetrodon by Dr. 
Case. The only regret one feels in connection 
with this memoir is that the critical section is 
obviously left incomplete, since it lacks a clear 
expression of the authors’ views as to the ordi- 
nal classification of the Permian reptiles. 
H. F. O. 
INTERNATIONAL CONGRESS OF PHYSICS. 
The preliminary announcement of the con- 
gress is as follows: 
La Société francaise de physique a pris l’initia- 
tive de provoquer, 4 l’occasion de |’ Exposition 
universelle de 1900, une réunion en Congrés 
international de toutes les personnes qui s’intér- 
essent aux progrés de la physique. II] n’est pas 
besoin de faire ressortir les avantages considér- 
ables que 1’on est en droit d’attendre, au profit 
de la science, d’une telle réunion ; jusqu’a pré- 
sent des congrés spéciaux, tels que les congrés 
d’électricité, ont conduit 4 des résultats que 
tous les physiciens connaissent et apprécient, 
mais jamais encore n’a eu lieu un congreés inter- 
national consacré dla Physique générale ; il est 
permis d’espérer que cette premiére réunion pré- 
sentera un grand intérét. 
Un Comité d’organisation a été constitué, qui 
a décidé que le Congrés international de phys- 
ique s’ouvrirait le Jundi 6 aott 1900, et durerait 
une semaine. Le Congrés sera rattaché 4 l’en- 
semble des Congrés rentrant dans |’ organisation 
de l’Exposition universelle; la séance d’ouver- 
ture aura lieu au Palais des Congrés. 
Il n’a pas semblé au Comité que l’on dat, 
dés 4 présent, fixer d’une fagon définitive le 
programme des travaux du Congrés; nous 
avons l’honneur de vous soumettre un projet 
