236 ~ B. S. Lull — Carboniferous Footprints. 



The maims, on the other hand, differs markedly, that of 

 the present form being proportionately mnch smaller, 

 especially in the length of the abbreviated digits, the for- 

 mula of which can not be ascertained. 



In some respects the new form suggests Dromopus 

 velox Matthew 4 bnt is mnch larger and differs again in 

 the relative size of hand and foot. The assignment to the 

 genus Dromopus, therefore, may be taken as provisional. 



Williston expressed the opinion that in Dromopus 

 agilis we had the veritable footprint of a reptile, and it is 

 quite probable that this new species was also of reptilian 

 rather than amphibian lineage. "Williston 's Isodectes 

 copei from the Coal Measures of Ohio, which he regards 

 as the oldest known reptile, and the foot of which would 

 make an impression not unlike that of D. agilis, is evi- 

 dence for the possibility of reptilian existence at this 

 remote period. 



I am deeply indebted to Professor Woodworth for the 

 privilege of describing this most interesting form. The 

 type is preserved in the Geological Museum of Harvard 

 University. 



4 G. F. Matthew, Trans. Eoy. Soc. Canada (2), 10, sect. 4, 86, pi. 2, figs, 

 la, b, 1904. 



SCIENTIFIC INTELLIGENCE. 



I. Geology 



1. Topographic Maps and Sketch Mapping; by J. K. Finch. 

 Pp. xi+175, 77 text figs., 1 map ; New York (John Wiley & Sons), 

 1920. — During the great war there was a decided demand for a 

 text-book on map reading and sketch mapping, and this stimulus 

 has brought the book under notice. Moreover, the general public 

 has discovered the fine topographic maps issued by the U. S. 

 Geological Survey, and this book will help to a better under- 

 standing of them. It is a small volume, abundantly illustrated, 

 and recommended to instructors in geology and geography, and 

 to civil engineers. There is also an appendix presenting a 

 descriptive list of the principal topographic maps of the world, 

 by F. K. Morris. 



2. The Porto Rico Earthquake of 1918. Report of the 

 Earthquake Investigation Commission; by H. F. Reid and 

 Stephen Taber. House of Representatives, Document No. 269, 



