634 



THE AM ERIC AX NATURALIST. [Vol. XXXVII. 



made a thorough-going embryological study of the carpus and tarsus of 

 the problematic mammal Hyrax. Since in the embryo the hind foot 

 shows traces of the first and fifth digits, the extremities of Hyrax 

 point to derivation from a primitive form with five digits. The 

 embryonic carpus contains two centralia like the embryonic carpus 

 of the turtle. Traces of both prepollex and prehallux were found. 

 The carpus and tarsus of Hyrax must have been derived from a more 

 primitive form than Phenacodus. Since they show as many affinities 

 to the rodents as to the fossil ungulates, Hyrax has probably been 

 derived from some form in which these two types were united, the 

 Toxodontia, or possibly the more primitive Tillodontia. 



The growth of micro-photography has been so rapid that the A B C 

 of the subject has been issued in a handy volume by W. H. Walmsley 

 (N. Y., Tennant & Ward, 1903. iv-155 pp., 13 pis.). Chapters are 

 devoted to the microscope, the camera, illumination, negative making 

 and printing. The experience of an expert, the high quality of 

 whose work is attested by the illustrations that accompany the 

 volume, is given freely to the beginner. 



BOTANY. 



Setchell and Gardner's N. W. Algae. 1 — This is a careful and 

 thorough account of the marine Alga; of the 1'acitic coast of America 

 from Cape Flattery north to the Arctic Ocean, and of the fresh water 

 species found near the shore through the same range, the Diatomaceae 

 and Desmidiaceae excepted. The information hitherto accessible has 

 been scattered through many books and papers in various languages, 

 and this is now brought together, but covers only the smaller part of 

 the present work, the rest being now presented by the authors for the 

 first time. This is specially the case as to the fresh water Algae, in 

 regard to which very little indeed is on record previous to this work. 



Every species mentioned by previous writers is included in this list, 

 even if the authors consider the determination as unreliable, or that 



Cal. Publications, Botany, Vol. 1, pp. 165-418; PI. XVII-XXVII. Berkeley, 



