Geology and Paleontology. 525 
whole, are referred by M. Barrois to the same horizon with the 
Eifelian beds of the Rhine. 
The coral limestone of Cabrieres (Herault, France) is by M. Bar- 
rois ranged between the Eifelian and the Coblencian stages of the 
evonian 
CARBONIFEROUS.—Spirodomus insignis, is a peculiar, spirally- 
twisted lamellibranch, recently described by Chas. E. Beecher, from 
the attenuated Waverly series of northwestern Pennsylvania. In 
its reflexed and minutely plicated margins and absence of proper 
hinge, this shell-suggests some forms of Pholas, and its spiral form 
seems to indicate a burrowing habit. 
Among the impressions of fishes collected in the shales of the 
coal-beds of Commentry are some with a cartilaginous skeleton 
ossified at certain points and presenting peculiarities not to be found 
in any other living or extinct fish. The study of twenty-three 
examples of this fish, some of them in a good state of preservation, 
has enabled M. Brongniart to describe it under the name of Pleura- 
canthus gaudryi. In form this fish resembles a shark, and in length 
it varies from eighteen to forty inches. 
Jurassic.—Dr, E. Fraas (Paleontographica, Band 32) treats of 
the asteriads of the White Jura of Swabia and Franconia, with re- 
searches into the structure of echinoderms and the skeleton of the 
Asteroidea. He describes as new Astropecten infirmum and A 
ans; also Pentacerus pustuliferus, from the lithographic schists 
of Kelheim. 
__E. Koken (Paleont. Abhandl., 1887) has contributed additional 
information upon the Dinosauria, Crocodilia, and Sauropterygia of 
the Wealden of Northern Germany. Among the crocodiles, Gonio- 
pholis pugnax and G. minor, and among the Sauropterygia, Plesio- 
saurus degenhardti, Pl, limnophilus, and a third unnamed Plesio- 
Saurus, are new. The work also contains much information upon 
the development of the brain and auditory passages of the genus 
Macrorhynchus. 
; CRETACEOUs.— Gigantichthys pharao is the name given to a fos- 
sil fish of the family Trichiuride, collected by Professor Schwein- 
urth in the cretaceous beds of Egypt, within ten kilometres of the 
Pyramids of Gizeh. 
Cxnozo1c.—Dr. O. Roger concludes (Ueber Dinotherium bavari- 
cum, Palwontographica, Band 32) that D. bavaricum is the smaller, 
older ancestral form, contemporary with Anchitherium, out of which, 
y a series of transitional forms, the gigantic Din. giganteum 
Was finally developed in the Hipparion period. : 
In 1885 Professor M. Neumayr and Dr. I.. v. Tausch undertook 
explorations in the Pliocene beds of Pikermi, near Athens, for the- 
