THE AMERICAN NATURALIST [Vol. XLIII 



Efforts to secure embryos of Cassiopea xamachana were unavail- 

 ing, no males being found even though over one hundred indi- 

 viduals were examined! 



Linton's studies on parasitic worms lead him to the con- 

 clusion that generally these organisms are not as abundant 

 either in species or individuals, for an equal number of hosts 

 (fishes) in tropical as in northern waters. 



An interesting case of identification is mentioned by Linton. 

 The spiral valve of some shark, with its contents, came to him 

 for study. From the entozoa present, taken with the other 

 intestinal contents, he concluded that the organ belonged to 

 Galeacerdo tigrinus. It was later found that the jaws of the 

 specimen had been saved. Examination of these proved the 

 original identification to have been right. Question: Where 

 were the "determinants" of the characters by which this identi- 

 fication was made? Were they in the germ-cells of the shark 

 or in those of the entozoa that inhabited the shark's intestine? 

 Of course the case would present no difficulty to a consistent 

 determinantist because the determinant doctrine is founded (un- 

 wittingly) exactly on such an a priori basis that observed facts 

 can not touch it. As well expect to hurt a ghost with a charge 

 of buck shot, as the determinant theory with objective facts. 



Several new species and genera of endoparasitic worms are 

 described in the paper. 



Animal Behavior: Under this head come the largest number 

 of titles and, on the whole, probably the most important observa- 

 tions contained in the volumes. This is as it should be, coming, 

 as the studies do, from a laboratory located by design in a 

 peculiarly rich zoological region that is at the same time remote 

 from the great centers of scientific activity. The titles are: 

 "The Annual Breeding-Swarm of the Atlantic Palolo," by A. 

 G. Mayer; "Rhythmical Pulsation in Seyphomedusse, " by A. G. 

 Mayer; "Habits, Reactions and Associations in Ocypoda 

 arenaria," by R. P. Cowles; "Habits, Reactions and Mating 

 Instincts of the Walking Stick, Aplopus mayeri," by C. R. 

 Stockard; "A Contribution to the Life-History of the Booby 

 and Man-o'-War Bird," by F. M. Chapman; "The Behavior of 

 Noddy and Sooty Terns," by J. B. Watson; and "An Experi- 

 mental Field-study of Warning Coloration in Coral-reef Fishes," 

 by Jacob Reighard. 

 As already indicated, some of the papers noticed under other 



