1896.] Anthropology. 255 



plasticity of the mammal infant as opposed to the highly developed in- 

 stinctive equipment of other young; the maternal care, instruction 

 and example during the period of helplessness, and the very gradual 

 attainment of the activities of self-maintenance in conditions in which 

 social activities are absolutely essential. All this stock of the develop- 

 ment theory is available to confirm this view. 



And to finish where we began, all this is through that wonderful 

 engine of development, consciousness. For consciousness is the avenue 

 of all social influences.— J. Mark Baldwin, Princeton. 



The preceding communication from Prof. Baldwin is copied from Science of 

 August 28, 1896. It is reprinted in order to render intelligible a review of it 

 which I propose to publish in the next number o" " " 



ANTHROPOLOGY. 1 



Mercer's Cave Explorations in Yucatan.'— This a hand- 

 somely illustrated volume which describes in detail the researches 

 made by the Corwith Expedition to Yucatan, under the direction of 

 Mr. H. C. Mercer of the University of Pennsylvania. The object of 

 the expedition was to search for the remains of prehistoric man in the 

 cave deposits, and to learn who were the predecessors or ancestors of 

 the peoples whose civilization is attested by the remarkable ruins 

 which are such a conspicuous feature of that country. Explorations 

 of this kind made in Europe have achieved such important results to 

 archeology, that every research in America must be watched with 

 great interest. As a summary of his work, Mr. Mercer remarks : 



" The intervening two months seemed a long time ; nor was it easy 

 to realize that, after all, the area gone over had not exceeded one 

 hundred miles in length by ten in breadth. Twenty-nine caves had 

 been visited in sixty days, of which ten had been excavated. Thirteen 

 had archeological significance. Six had yielded valuable, and three, 

 decisive results. 



" We had seen but little of the ruins. We had not passed south- 

 ward over the boundary line into the great wilderness, whence fables 

 of lost cities reach the traveller's ear. Our continued study of an un- 



1 This department is edited by H. C. Mercer, Univer.-ity of Pennsylvania. 



8 The Hill Caves of Yucatan : A Search for the Evidence of Man's Antiquity 

 in Central America ; being an account of the Corwith Expedition of the Depart- 

 ment of Archeology and Paleontology of the University of Pennsylvania, by 

 Henry C Mercer. J- B. Lippincott & Co. Philadelphia, 1896. 8vo., pp. 183. 



