94 
POPULAR SCIENCE REYIEAY. 
GEOLOGY AND PALEONTOLOGY. 
Tinoceras anceps ; what is it ? — This is a large mammal from the Tertiary 
formation of Wyoming, U.S.A., discovered by Mr. 0. C. Marsh. In 
Silliman’s American Journal” for October the discoverer states that he has 
proved it to be a proboscidean. The limb bones of this animal are similar 
to those of Mastodon^ but other parts of the skeleton, especially the skull, 
differ widely from that genus. The Museum of Yale College has portions 
of several skeletons, which will soon be fully described. 
A Palceontologist exploring. — We hear that Professor Joseph Leidy, the 
eminent comparative anatomist of Philadelphia, is exploring the West for 
fossil vertebrates. He is also making a study of the minute forms of life 
under the microscope, and will present a report on the minute fauna and 
flora of the districts he visits. 
Fossil Crustacea of the Limtdoid type . — Mr. Henry Woodward communi- 
cates to the Geological Magazine ” [October] some remarks on the order 
merostomata, additional to those in his splendid memoir in the Palaeonto- 
graphical Society’s publications. Since 1865, when he very fully described some 
of the Limuloid forms to the Geological Society, other fragments have been 
found, and also another nearly perfect example (obtained by the late Mr. 
Henry Wyatt-Edgell) of the form named by Mr. Woodward Hemiaspis 
limuloides, which, having the upper central portion of the carapace preserved, 
nearly completes our knowledge of this species. The great interest attach- 
ing to this form arises from the fact that it offers] ust the desiderated link by 
which to connect the Xiphosura with the Eurypterida. Limulij apparently 
d.ififering but little as regards their carapace from the recent species now 
found living on the coasts of China, Japan, and the north-east coast of 
North America, occur as early as the deposition of the Solenhofen Lime- 
. stone of Bavaria ; and in the Coal-measures of England and Ireland several 
species of Bellmuri and Frestwichice occur, in which behind the cephalic 
shield the body is composed of five more or less free thoraic segments, and 
the rudimentary abdomen, if not anchylosed in all, is so in most. Mr. 
Woodward’s present paper is of considerable length, and is illustrated by a 
capital plate. 
The Trimmer ellids. — The labours of Professor King and Mr. T. Davidson, 
E.B.S., on these fossils, have enabled them to confirm, for the most part, 
the conclusions of previous writers as to the numbers of species, and to 
determine the existence of some others. The three genera are severally 
constituted in species as follows : — 
Trimerella grandis, Billings. 
„ acuminata^ Billings. 
„ Lindstromi, Dali. 
„ Billingsii, Dali. 
,, Ohioensis, Meek. 
„ Dalli, Dav. and King. 
„ JF^s5?/ews^s,Dav. and King. 
Einobolus Conradij Hall. 
„ Canadensis, Billings. 
Dinoholu-s Galtensis, Billings. 
„ Davidsoni, Salter. 
„ transversus, Salter. 
,, Woodwardi, Salter. 
„ maghifica, Billings. 
Monomerella Walmstedti, Dav. and 
King. 
„ prisca, Billings. 
„ orhicidaris, Billings. 
