Reviews — A Century of Science in America. 279 



morphological speculations. Apart from this, however, there are 

 many difficulties in accepting the derivation of the Cirripedia here 

 suggested. The recent Phyllocarida are, beyond a doubt, members 

 of the sub-class Malacostraca, and it can only lead to confusion if 

 thev are grouped under the Phyllopoda. There is no hint of affinity 

 ■with them in the structure of recent Cirripedia. They differ widely 

 in the regions of the body, the structure and grouping of the 

 appendages, and the position of the genital apertures. The 

 resemblances which Mr. E,uedemann has to set against these 

 differences are trivial and far-fetched. It is possible that the 

 Cirripedes have been derived from Phyllocarida, but Mr. Puedemann 

 does not convince us that it is probable. 



Mr. J. M. Clarke, accepting Mr. Puedemann's hypothesis with 

 regard to the sessile barnacles, tries to show that the pedunculated 

 forms were independently evolved from the Phyllocarida by way of 

 the obscure genera Lepidocoleus, Turrilepas, and Strobilepas. If 

 these genera are Cirripedes at all, which, according to Withers, is 

 more than doubtful, their connexion with the normal Pedunculata 

 lias still to be elucidated. If the latter have been evolved inde- 

 pendently of the Operculata from ancestors that were not Cirripedia, 

 the resemblances between the two groups go far beyond any case of 

 convergence hitherto recognized. 



Phylogenetic speculations are of value in proportion to the extent 

 and importance of the facts on which they are based. In these two 

 papers the foundation appears altogether inadequate to sustain the 

 superstructure. 



W. T. C. 



TIL — A Centtjey of Science in America, with Special Reference 

 to the American Journal of Science, 1818-1918. Edited 

 by E. S. Dana. pp. 458, with 22 portraits. Tale University 

 Press, 1918. 84. 



THIS handsome volume is published in commemoration of the 

 centenary of the founding of the American Journal of Science 

 by Benjamin Silliman in July, 1818. Some of the chapters were 

 based on a series of seven Silliman Memorial Lectures, and the 

 whole cost of publication has been defrayed from the income of the 

 Silliman Memorial Fund. As might naturally be expected, there- 

 fore, the subject-matter is very largely geological and mineral ogical, 

 but some 150 pages are occupied by chapters on the progress of 

 chemistry, physics, zoology, and botany, each contributed by a 

 specialist in his own subject. The first chapter, by the editor, 

 details at some length the history of the American Journal of Science 

 aud the gradual evolution which it has undergone, from its earliest 

 beginnings as a magazine of science, agriculture, and the arts, to its 

 present rather specialized form, in which geology and mineralogy 

 are dominant. It is shown that its foundation marks the beginnings 

 ■of active scientific research on modern lines in the United States, 

 and its progress is coeval with the extraordinary development of 

 science in that country. The other chapters are written by men of 

 light and leading in their respective spheres, and give admirable 



