26o REVIEWS 



these bulbs, when in their original position, occur with the stalked 

 end upward and not downward as previously supposed, the bulb being 

 merely a distal specialization of a true root and not a float. 



The bulb-Kke process may itself be described as a 

 rigid, hollow, chambered root, consisting of a large spheroidal bulb with a short 

 projecting collar, a stem base with bifurcating roots resting in and forming 

 a large part of the floor within the collar; and several internal, laterally opposed 



sacs which abut against the inner side of the bulb wall The collar and 



bulb waU consist of single layers of similar plates derived from rootlet systems 

 originating at the ends of the proximal root branches. 



Eight species of Scyphocrinus occurring in America are described and 

 are figured together with several species of other genera. A table of 

 analysis of the American forms is given. 



A. C. McF. 



The American Species of Orthophragmina and Lepidocyclina. By 

 Joseph A. Cushman. Shorter Contributions to General Geol- 

 ogy. U.S. Geological Survey, Professional Paper 125 D, 1920. 

 Pp. 39-108, pis. 7-35. 



The genera Orthophragmina and Lepidocyclina belong to the group 

 of orbitoid Foraminifera, a group of excellent horizon-markers due to 

 their limited stratigraphic range, wide geographic distribution, and 

 great abundance in the Tertiary. Hitherto the group has received but 

 little attention by American paleontologists. In the present paper the 

 author describes all known American species, which form but a small 

 percentage of those which he believes will be later described and have 

 been described from the European Tertiary. 



Orthophragmina includes those species characterized by the presence 

 of rectangular chambers in the equatorial band. The genus is limited, 

 so far as known, to the Eocene, and in America, chiefly to the upper 

 part. Lepidocyclina differs in that the chambers of the equatorial belt 

 are t3^ically hexagonal. It ranges through the Eocene, and Lower and 

 Middle Oligocene. 



Sixteen species of Orthophragmina are described, of which two are 

 new, and thirty species and varieties of Lepidocyclina of which eleven 

 are new. The author includes a table of tentative correlations of the 

 Tertiary of Panama by T. W. Vaughan, a key to the species of Lepido- 

 cyclina and a list of those species which are considered as good index 



forms for the Tertiary of the Coastal Plain. 



A. C. McF. 



