Reviezv of Recent Geological Literature. 125 
REVIEW OF RECENT GEOLOGICAL 
LITERATURE. 
Supplement till om Acerocarezotten, also Eii trilobit frdn Skdnes 
Dictyo^^raptuss/ciffer, 3.i ]ovi.(Zvi.u. Mobekg. (Geo), foren i Stockholm 
forhandl. Bd. 20, Hf. 5, 1898.) 
These pamphlets by Dr. J. C. Moberg are an illustration of the thor- 
ough way in whidh the Swedes are working up the natural history and 
geology of their country. Not only are the Paleozoic faunas being fully 
elaborated, but the exact horizon at which the several species are found 
(so important for a proper understanding of the succession of living be- 
ings upon the globe) is being carefully determined. 
The first pamphlet adds to our knowledge of the species Acerocare- 
claitdicaiis, A granulatiDii and Parabolina heres, which are described! 
in the original article by this author and H. MoUer on the Acerocare 
zone, especially the first species. 
The second pamphlet describes a remarkable trilobite of the Dic- 
tyonema slates, heretofore devoid of trilobites, which is of interest as 
showing a curious combination of .the characters of Cambrian and Ordo- 
vician trilobites. The species is supposed to be a new genus Hystrolenus 
and is named H. toniqznsti. It has pygidial spines like Ctenopyge and 
pygidial segments like Dicellocephalus. By the sculpturing of the 
glabella, the position of the eye, and the course of the facial suture it re : 
sembles Niobe. The author compares Hystrolenus to Asaphalina Mun.- 
Cham and Berg., which he considers the must nearly related genus. 
Each of these articles is accompanied with a plate showing parts of 
the various species described. G. f. m. 
Topaz crystals in the mineral collection of the (J. S. National Muse-^ 
urn. By Arthur S. Eakle. (Proc. U. S. Nat. Museum, vol. 21, pp. 
36i-369'[No. 1 148], 1898.) 
This article describes the crystals of this attractive mineral in- 
cluded in the Museum collection. The forms occurring on the crystals 
from the dififerent localities are listed and illustrated by figures, and 
in some cases forms not hitherto reported from certain localities are 
noted, but no forms new to the mineral were found. u. s. o. 
Distribution of Metallic wealth in Arizona. W. P. Blake, territor- 
ial geologist, [included in the report of the governor of Arizona for the 
year ended June 30, 1898]. 
This report gives, along with a birdseye view of the location 
and extent of the main mining belt, which is a mountainous tract ex- 
tending from N. W. to S. E. across Arizona a distance of nearly 500 
miles, many special facts of interest, and some geological notes of 
broader significance, and a summary of economic mineralogy not 
metalliferous. It is a report that cannot tail to interest both geologists 
and miners, as well as capitalists who are seeking information con- 
cerning Arizona. x. h. w. 
