578 



SCIENCE 



[N. S. Vol. LIV. No. 1406. 



medical sciences, particularly in their bear- 

 ing upon clinical medicine and human physi- 

 ology. This point of view is most important 

 and far too often neglected in our American 

 schools of medicine, where the medical sci- 

 ences and clinics are so thoroughly dissoci- 

 ated. The book should continue to be of 

 general interest to the medical profession as 

 it is of nearly equal value to medical stu- 

 dents and to our practising physicians. 



It is somewhat unfortunate that the pub- 

 lishing has been made so elaborate. If there 

 were fewer colored illustrations and fewer 

 plates the price of the book could probably 

 have been markedly reduced without a cor- 

 responding reduction of its instructive value. 

 J. C. AuB 



Harvard Medical School 



Triassic Fishes from Spitzhergen. By Erik 



A: Son Stensio. Upsala, 1921. 



This is one of the most important paleon- 

 tological memoirs which has appeared in recent 

 years. It represents an attempt to distinguish 

 fossil fishes as organisms, rather than as hori- 

 zon markers. The geological aspects of the 

 question are, however, thoroughly discussed. 



Stensio is a student of Professor 0. Wiman 

 of Upsala, whose contributions during the last 

 few years have interested paleontologists in the 

 fauna of ancient Spitzhergen. Wiman has sent 

 or led expeditions into Spitzhergen since 1908, 

 and on the basis of the material thus assem- 

 bled the present writer Stensio has based his 

 account. 



The quarto, representing Part I. of Stensio's 

 studies, consists of 307 pages of printed matter, 

 35 plates and 90 figures in the text. The press- 

 work coming from Vienna is excellent. The 

 plates represent photographic reproductions of 

 the fossils, with Stensio's interpretations of the 

 anatomy lettered in white ink in the photo- 

 graphs. The results are especially pleasing and 

 easy of reference. 



Elasmobranchs, dipnoans, crossopterygians 

 and three families of Actinopterygii constitute 

 the fauna and Stensio has described and inter- 

 preted his findings in a very excellent manner. 

 Especially interesting are his accounts of the 



sensory canals of the head; the relationship of 

 the crossopterygians and the tetrapods and the 

 correlations of the primordial ossifications of 

 the head of these primitive forms. It is a grate- 

 ful relief to find taxonomy in the background. 

 Nomenclature often absorbs more space than is 

 needful. 



EoY L. MOODIE 

 IJNrvERsiTT or Illinois, 

 Department of Anatomt, 

 Chicago 



SPECIAL ARTICLES 



INHIBITORY EFFECT OF DERMAL SECRETION 



OF THE SEA-URCHIN UPON THE FERTILI- 



ZABILITY OF THE EGG 



In the early part of September of this year 

 (1921), while working in the Marine Biological 

 Laboratory at Woods Hole, Mass.,"^ I happened 

 to find a striking fact that the eggs of Arhacia 

 punctulata obtained through the genital pores, 

 as most commonly practised,^ did not develop 

 at all, whereas those taken out from inside the 

 shell developed normally. The results of a few 

 but repeated experiments carried out with re- 

 gard to this peculiar phenomenon may be given 

 summarily as follows : 



The eggs which escaped through the genital 

 pores of opened sea-urchins, and were then 

 transferred to clean sea-water in finger bowls, 

 but subjected to no subsequent washing, were 

 seen attracting spermatozoa but no fertilization 

 occurred. These eggs were later washed re- 

 peatedly with clean sea-water at various inter- 

 vals. If simply washed they never developed. 

 But at a fresh insemination these washed eggs 

 began to develop; thus, for example, the eggs 

 washed and inseminated after standing for 50 

 hours in room temperature were found still 

 capable of developing into normal and healthy 



1 My hearty thanks are due to Professor E. B. 

 Wilson for the privilege of the use of a Columbia 

 University table in the Marine Biological Labora- 

 tory, and to Professor F. R. Lillie, director, and 

 other members of the staff of the said laboratory 

 for every facility for my work. Further, to Pro- 

 fessor E. G. Conklin, who has kindly criticized and 

 corrected the manuscript, I express my sincere 

 thanks. 



2 See F. E. Lillie, Biol. Bull., XXVIII., 4, 1915, 

 p. 231. 



