Rct'iciu of Recent Geological Literature. .51 
Siliceous Calcites from the Bad Lands of South Dakota; by S. L. Pen- 
field and W. E. Ford. (Am. J. Sci, 260-352-351-, with PI.) 
The cr\'stals are rough in appearance, but show with some distinct- 
ness characteristic calcite forms. In chemical composition the crystals 
resemble the siliceous calcites from Fontainebleau, containing 40% of 
calcite and 60 of sand. The sand grains at times attain the size of small 
pebbles. It appears that these crystals represent a phase of sandstone 
formation where the calcareous cement was able to crystalise and pre- 
serve its external crystalline form. c. ii. w. 
Granites of Southern Rhode Island mid Connecticut, witli Observations 
on At/antic Coast Granites in General. By J. F. Kemp. (Bull. Geol. 
Soc. Aw., 10,361-382.) 
All the granites described are biotite granites, muscovite, though 
present, being very subordinate and hornblende failing entirely. 
The following types are recognized: Westerly gray, Westerly red. 
Stony Creek red, Stony Creek gray, and Lyme pink. The Petro- 
graphic descriptions of these types and of the contact phenomena 
and basic inclusions as well as of the associated apatite and pegmatyte, 
are followed by a discussion of the chemical composition based upon 
six analyses, four of which are new. The silica is quite uniforiji, 
varying from 68.40 to 73.05, but with onl>i one below 70 per cent. 
The Rhode Island granites run somewhat higher in lime than the 
Connecticut granites. The magnesia is very low in nearlj^ everj'^ 
case. The soda, in relation to the potash, is relatively high in some 
types and low in others; while one, the red granite of Stony Creek, 
proves to be one of the purest potash granites on record. The paper 
closes with a general review of the granites of the Atlantic sea board, 
which are believed to belong to several different geological periods and 
among which the biotite granites largely predominate. w. 0. c. 
Contact Metamorphism of a Basic Igneous Rock. By Ulysses 
Sherman Grant. {Bull. Geol. Soc. Am., 11, 503-510.) 
The rock referred to is the Keweenawan gabbro occupying a 
roughly crescentic area of about 1,000 square miles in the northeast 
corner of Minnesota, between lake Superior and the Canadian bound- 
ary. The contact phenomena are described only for the northwestern 
border of the gabbro which the author regards as probably intrusive,, 
where it lies upon the Archaean, Kecwatin and, especially the quartzyte, 
iron-bearing series, carbonaceous slate and graywacke slate of the Ani- 
mikie. The metaporphism is very noticeable, and consists of a partial 
or complete recrystaliization of the adjacent rocks. Complete recrys- 
tallizntiion is the rule near the contact, and in places this extends 500 
feet from the contact; while a partial recrystaliization is at times no- 
ticeable for two or three times this distance from the present margin 
of the gabbro. The rather normal metamorphic characters of the slaty 
members of the Animikie are first briefly noticed, and then the special- 
ly interesting contact phenomena of the iron-bearing series are more 
fully decribed. The original rock is regarded as having more or less 
