Review of Recent Geological Literature. 123 
in this rock. Another form of the Olenellus sandstone is a glauconite 
bearing sandstone which has yielded a few species of fossils in abund- 
ance. Other forms of the rock are rusty sandstone, gray quartzose 
sandstone, variegated sandstone and a bluish calcareous sandstone. 
Olenellus stands at the front among these fossils for number but 
the pieces are fragmentary, and so the species could not be determined. 
A doubtful fragment of a Paradoxides was found, but the determin- 
ation to this genus is quite uncertain, and it is associated with an Ari- 
onellus and an Ellipsocephalus which are of a type similar to those 
found below the Paradoxides beds. 
NOTES ON THE FAUNA. 
Herr Wiman's excellent figures give a very good presentation of this 
fauna of fragments from the Drift, etc., of northern Sweden and afford 
some interesting comparisons with those of North America. Some of 
the most widely distributed fossils are fragments of Olenellus; out of 
two score of occurrences of this trilibite only fifteen fragments are 
figured and these badly broken; the genus is recognized by its sculpture. 
The Arionellus is of the sub-genius Strenuella which ocenrs in the Up- 
per Etcheminian fauna of Newfoundland. The Ellipsocephalus may be 
compared with E. galeatus Matt, of the Protolenus fauna. Hipponi- 
charion and Beyrichona characterize the same fauna. 
The shells referred to Acrotreta show their antiquity by the de- 
pressed umbo, as well as by the convex anterior slope of the ventral 
valve of one species. The internal markings are not shown so one does 
not know whether they belong to Acrotreta, or Acrothyra, but the form 
of the shells conforms to that of the Acrothyra? of the Lower Etche- 
minian fauna. 
Liugida bottnica is referred to the genus Lingula on account of the 
resemblance in the sculpture of the interior of the ventral valve to that 
of L. anatina Brug and L. palmeri Dav. ; the species may also be com- 
pared, as regards its high cardinal area, its general form, and the mark- 
ings of the ventral valve to Lingulepis longinervis Mat' of the Lower 
Etcheminian fauna. 
A remarkable fossil is that described as Causia formosa n. gen. et 
spec. To judge from the position it holds in the classification of the 
species, it would seem that it was recognized as a Neotrematous Brach- 
iopod ; it looks like a gigantic Acrothele. The ventral valve, the only 
one figured, is nearly 5 cm. across and 2 cm. high ; the front slope is 
hollow as is often the case in Acrothele. but the apex is broken away. 
\ slender curved conical shell has been described as Stenotheca 
COmu by Dr. Wiman, which reminds one of the various ways in which 
this generic term is used. It was originally applied by Salter to a quite 
small, thin-shelled, folded univalve or bivalve crustacean, thence it was 
Used for a conical calcareous gasteropod, similar in form when viewed 
from the side to the original Stenotheca, and later extended to more 
elongated conical shells. Dr. Wiman's use i^ similar to this last, hut 
he states that the shell is chitinous. 
