Abstracts of Foreign Memoirs. 167 
(Bengal) he considers to have, on the whole, a Liassic facies, although 
it contains one species (Z'eniopteris ovalis) which occurs in the 
Oolitic strata of Scarborough, and another, which he cannot dis- 
tinguish from the Dictyopteris Brongniarti of the Carboniferous (!) 
rocks of Saxony. Some of the species of Cycads are allied to those 
found in the Oolite, others to Liassic species, and some to species 
occurring in Triassic rocks; but the Liassic forms are said to be 
most prevalent. Respecting the North American beds, the author 
evidently inclines to the opinion that they are Triassic; he denies 
the correctness of Prof. Rogers’s determinations of the plants, but 
accepts those of Dr. Heer ; the former geologist endeavoured to show 
that these North American deposits were comparable with the Oolitic 
coal-bearing beds of Whitby, while the latter referred them either 
to the Keuper or the Lower Lias, The Australian strata are more 
ditticult to deal with, for while Professor M‘Coy considers the plants 
to be Oolitic, the Rev. W. B. Clarke asserts that he has found asso- 
ciated with them a true Carboniferous Lepidodendron, with Shells 
belonging to the same period. Sign. de Zigno coincides and Prof. 
M‘Coy in believing that the Lepidodendron and the Paleozoic shells 
found by the Rev. W. B. Clarke came from deposits much lower in 
the series than the strata which furnished the remaining plants ; but 
he differs from the Australian Professor as to the age of the latter, 
believing them to be either Trias or Lias. Thus it will be seen that 
Sign. de Zigno considers all these deposits as referable either to the 
Trias or the Lias. ‘This conclusion is not new, and, excluding the 
Australian beds, the age of which cannot as yet be considered de- 
termined, it is probably right, although the author’s arguments, 
derived from the very conflicting evidence of the Plants, are by no 
means so convincing as those of Professor Rupert Jones, which are 
drawn from the occurrence, in the Indian and American strata, of 
certain species of E’stheria, a genus, by the way, which Sign. de 
Zigno does not even mention, referring to the Richmond specimens of 
E. ovata as shells allied to ‘ Postdonomya’ minuta. Not less remark- 
able in the Memoir is the absence of all allusion to, the remarkable 
Glossopteris Browniana, which is said to occur in India, Australia, 
and South Africa; for evenif Sign. de Zigno prefers another generic 
name, the specific appellation ought still to remain; but these 
omissions, with the absence of allusion to the South African deposits, 
convince us that the author has not yet got to the bottom of this 
very intricate subject.—H. M. J. 
UEBERBLICK UBER DIE TRIAS, MIT BERUCKSICHTIGUNG IHRES VORKOMMENS IN DEN 
Aupren. Von Dr. Frreprich von Arprrti. Stuttgart, 1864. 8vo, pp. 353. 
7 Plates. : 
“eee object of this work is to give an outline of the present state 
of our knowledge of the Trias, and thus to complete or to correct 
the remarks made by the author in his memoir entitled ‘ Beitrag zu 
einer Monographie des bunten Sandsteins, Muschelkalks und Keu- 
pers, und die Verbindung dieser Gebilde zu einer Formation (Trias),’ 
