396 The American Geologist. December, 1893 
These significant results afford a charming exhibition of the achieve- 
ments of intelligent zeal in the handling of a most difficult subject. 
Only one familiar with the present requirements of the study of the 
fossil brachiopods can appreciate the author's good fortune in securing 
material adapted to such investigations, and comprehend the degree of 
patient labor necessary for its elucidation. 
Trematobohts : An Articulate Brachiopod of the Inarticulate Or- 
der. By G. P. Matthew. (Canadian Record of Science, Jan., 1893, pp. 
276 279.) 
This new brachiopod genus is described from the St. John group of 
Hanford Brook, N. B. Tt is interesting as showing, first, an hitherto 
unknown combination of the form and muscular characters of Obolus 
with the long pedicle channel of Schizambon opening near the center 
of the pedicle-valve; and secondly, well developed articulating pro- 
cesses on the pedicle-valve, with grooves or sockets on the opposite 
valve for their reception. Other genera have shown tendencies to 
span the conventional chasm between the edentulous and dentate 
brachiopods; Barroisella of the linguloide, Spondylobolus of the obol- 
oids, and now Trematobolus evinces. a similar inclination among the 
sipbonotretoids. There is, however, no evidence that any of these forms 
has left progressed descendants. 
Outline of the geological <in<l physical features of Maryland. By 
George H. Williams and William I!. Clark. Extract from the 
World's Fair book on Maryland prepared by the members of the faculty 
of Johns Hopkins University; 67 pages, with a geological map of the 
state and 16 plates; Baltimore, 1898. Price $1.00. By far the most 
pleasing and valuable part of this paper is the geological map of 
Maryland, which is the second geological map of the state ever pub- 
lished; the first was issued in L860, and since that time the geologist 
has had no convenient method of obtaining an idea of the areal dis- 
tribution of the various rock series in that state, as the first map is 
hard to obtain and needs many corrections. This new map was com- 
piled from all the available data and brings up to date our knowledge 
of the extent of the different formations and indicates the areas to 
which future stratigraphical and structural work should be directed. 
The practical value of the map is greatly enhanced by Prof. 
Milton Whitney's designations of the soils peculiar to each formation. 
The authors are to he congratulated upon the production of such a 
pleasing and harmonious piece of chromolithographs; it is certainly a 
good example of what can lie done in this line in America. 
The first part of the paper is devoted to a consideration of the phys- 
ical features of the state. As regards topography, Maryland can be di- 
vided into three pretty distinct provinces, each well marked by cer 
tain definite characters. These areas are known as the Coastal plain, 
the Piedmont plateau and the Appalachian region. In the Coastal 
plain is included the eastern half of the state; it is characterized by 
broad, level-topped stretches of country, which are cut by sluggish 
