August 2S, 1907] 



SCIENCE 



253 



feets in illustrations and iu statements (sucli 

 as that whicli eliminates Paneth's cells from 

 the duodenum), but the feature of this edition 

 is its embryological treatment. 



Professor Stohr believes that histogenesis is 

 too imperfectly known to be included in a 

 text-book of histology, and that morpho- 

 genesis is there out of place. Such figures 

 and embryological accounts as I have included 

 he draws and presents in lectures on sys- 

 tematic anatomy. The reviewer in Science, 

 however, believes that the idea of embryo- 

 logical arrangement is excellent, but that it 

 has not been properly carried out. Thus he 

 notes that the formation of the germ layers 

 is not described in human embryos, although 

 he does not state that human material is not 

 yet available. If the chick and pig are re- 

 ferred to when similar human embryos have 

 been described, it is because the student uses 

 the former in the laboratory. 



Another criticism is the failure to recognize 

 American investigators, who are seldom re- 

 ferred to by name, and who, it is said, are 

 " ignored " or " apparently unknown." Many 

 of the papers cited, as those of Bardeen, Mac- 

 Callum, Hendrickson, Calvert, Bensley, Opie, 

 and Flint were re-read by the editor im- 

 mediately before writing the corresponding 

 sections of the book. It has been Professor 

 Stohr's practice to omit personal references, 

 which he believes are out of place in an ele- 

 mentary histology. To do justice the book 

 should teem with such references. The con- 

 siderable number which I have introduced 

 refer to very recent, or to important contro- 

 verted work. A student should always have 

 access to the memoirs, but whether or not they 

 should be listed in an elementary text-book 

 is questionable. Since the reviewer in Sci- 

 ence believes that acknowledgment should 

 always be made, it seems unjust to him that 

 Professor Stohr should have modified his 

 diagrams of the spleen and lung after the ap- 

 pearance of Professor Mall's and Professor 

 Miller's work, respectively, without recording 

 his acknowledgments. I am informed that 

 Professor Stohr some time ago wrote to the 

 publishers that he had examined Dr. Miller's 



papers and used them as far as they seemed 

 right to him, and that the diagram was mostly 

 drawn according to Miller. 



Some microscopic discoveries may be readily 

 verified. Such was Professor Sabin's finding 

 of the jugular lymph sac in mammals, so 

 obvious a structure that I have a drawing of 

 it made by a student some years before her 

 paper explained its nature. In the text-book 

 this sac is described but its discoverer is not 

 recorded. Other findings, like those of the 

 splenic lobules and units and of the atria of 

 the lung may perhaps be verified after careful 

 study by special methods. If neither the 

 author nor the editor of the book is sure that 

 he can identify the atria, he can not honestly 

 describe them. 



Professor Mall's researches on connective 

 tissue which are thought by the reviewer to 

 have received insufficient attention, are re- 

 ferred to on pages 39, 42 and 50 with accom- 

 panying figures. Altogether it is quite prob- 

 able that German work is less fairly treated 

 than American in this text-book, but the 

 national element was not and should not be 

 considered. 



This edition of Stohr's " Histology " was 

 written to assist teachers in using the em- 

 bryological method of presenting the subject. 

 It is hoped that any teacher who is interested 

 in such a method will examine the book. 



Frederic T. Lewis 

 Cambetoge, Mass., 

 July 27, 1907 



SEISMOTECTONIC LINES AND LINEAMENTS — A 

 REJOINDER 



In the issue of Science for July 19, 1907 

 (pp. 90-93), Professor William M. Davis has 

 reviewed my recent paper, " On Some Prin- 

 ciples of Seismic Geology," published in Ger- 

 land's " Beitrage zur Geophysik " in March 

 last (vol. 8, pp. 219-292). To his statement 

 that " the seismotectonic lines seem, so far as 

 earthquakes are concerned, to be largely in- 

 fluenced in location and direction by the evi- 

 dently subjective element of the location of 

 cities and villages in which observers are 

 numerous," I would say, that some modifica- 



