616 



SCIENCE. 



LN. S. Vol. XVII. No. 433. 



south to the south pole remain unobserved. 

 For many years it has been my desire to 

 organize an expedition to the southern 

 hemisphere for the purpose of measuring 

 the velocity of these stars. With the ap- 

 proval and endorsement of the president, 

 the subject was brought to the attention of 

 Mr. D. 0. Mills, who most generously of- 

 fered to provide funds for constructing the 

 instruments, for defraying traveling ex- 

 penses, and for paying the salaries of the 

 astronomers engaging in the work. 



For this work, a Cassegrain reflecting 

 telescope is nearing completion. The para- 

 bolic mirror of thirty-six and one half 

 inches clear diameter and the convex mir- 

 ror of nine and four tenths inches are be- 

 ing constructed by the John A. Brashear 

 Company. 



A powerful three-prism spectrograph, 

 designed by the director for use with the 

 reflecting telescope, is completed. The 

 delicate parts of the mounting were con- 

 structed by our instrument-maker, and the 

 optical parts by the John A. Brashear 

 Company. Mr. Wright has submitted the 

 >vhole spectrograph to severe tests. Its 

 performance appears to be superior even 

 to that of the original Mills spectrograph. 

 A modern steel dome was built for the ex- 

 pedition by the Warner and Swasey Com- 

 pany. The minor pieces of apparatus 

 required have all been provided. It is 

 planned to select a suitable observing sta- 

 tion in the vicinity of Santiago, Chili. It 

 is confidently hoped that this work will be 

 at least as fruitful as that carried on with 

 the Mills spectrograph attached to the 

 thirty-six inch equatorial. 



The director wishes to make full ac- 

 knowledgment of the enthusiastic support 

 afforded him by the members of the ob- 

 servatory stafi'. Every man has been 

 ready to make the most of the opportuni- 

 ties supplied by the splendid instruments, 



by the unexcelled climatic conditions, and 

 by the excellent policy inaugurated for the 

 observatory by the officers of the Univer- 

 sity of California. 



W. W. Campbell, 

 Director of the Lick Observatory. 



SCIENTIFIC BOOKS. 

 Der Hercynische Florenhezirh. Grundziige 

 der Pflanzenverhreitung im mitteldeutschen 

 Berg- und Hilgellande vom Harz his zur 

 Bhon, his zur Lausitz und dem Bohmer 

 Walde. Von O. Deude. Leipzig, Engel- 

 mann. 1902. Pp. six + 671. 

 This is the sixth volume in the series of 

 monographs of Engler and Drude under the 

 general title of ' Vegetation der Erde.' Hav- 

 ing been specially elaborated by Dr. Drude^ 

 it may be taken to represent the standard 

 adopted and the principles which it is de- 

 signed to embody as the work progresses 

 farther. The region covered includes central 

 Germany, and is familiar to the author, as 

 he tells us, through thirty years of field and 

 herbarium work. 



As indicated in previous volumes, the scope 

 of the general work is a study of the vegeta- 

 tion of the earth from the standpoint of geo- 

 logical development, on the one hand, and 

 adaptations to environment, on the other. By 

 a natural division of material and labor, two 

 lines of work have been developed, namely, 

 floristic observations and the study of biolog- 

 ical relations. It is to the first of these that 

 the present volume is mainly, though not ex- 

 clusively, devoted. 



The discussion of geographical and clima- 

 tological data is followed by a brief statistical 

 resume, in which it appears that, within the 

 limits of the Hercynian region, 1,564 vascular 

 plants occur, besides some 645 species of bryo- 

 phytes, and possibly 2,000 or more thallo- 

 phytes. The flora is a composite in which 

 occur numerous Baltic elements associated 

 with northern Alpine forms, and in which 

 north Atlantic species as well as circumpolar 

 Arctic ones are also represented. There are 

 in the whole region but few, and these not 

 strongly marked, species that do not occur in 



