SCIENCE. 



Editorial Comjiittee : S. Newcomb, Mathematics ; R. S. Woodward, Mechanics ; E. C. Pickering, As- 

 tronomy ; T. C. ilEXDESHALL, Physics ; R. H. Thukstox, Engineering ; Ira Rejisen, Chemistry ; 

 J. Le CoXTE, Geology; W. M. Davis, Physiography; 0. C. Marsh, Paleontology; W. K. Bro<iks, 

 ■ Invertebrate Zoology ; C. Hart JIerriaji, Vertebrate Zoology ; S. H. Scviider, Entomology ; 

 N. L. Brittox, Botany ; Hexry F. Osborx, General Biology ; H. P. Bowditch, 

 Physiology ; J. S. Billings, Hygiene ; J. McKeen Cattell, Psychology ; 

 Daxiel G. Brixton, J. W. Powell, Anthropology. 



Friday, June 7, 1895. 



coy TENTS: 



A D;iitfimie<il Hi/potliesis of Inheritance (II-) ■' 



* John A. Ryder 617 



Sciaicc in Oinaila : J. T. C 628 



Onl Liidwig : FREDERICK S. Lee 630 



Correspondence : — 632 



Tilt Fro;/ lias not Brinnler^, hut Dicercbrized : 

 Burt G. Wilder. Tc.rf-bool- of Inrcrtchrate 

 ilorphoUigii : J. PlayfaiR McMureicH; A. 

 S. Packard. 



Scientific Literature : — 634 



KenCs Engineers' Pockei-Book : R. H. TlllBS- 

 TOX. Birdcnft: C. H. M. Behrn'x Anleiliing 

 zur Microchimischen Analgse : E. ReXOUF. 



Notes and Xews : — 636 



The American Association ; The British Associa- 

 tion ; Mechanical Interpretation of Variations in 

 Latitude ; A Xew Quadruple Expansion Engine ; 

 The Missouri Botanical Garden ; The Hoyal Astro- 

 nom ical Society ; General. 



Scientific Journals : — 6-12 



The American Chemical Journal; The Botanical 

 Gazette ; The Pijschological Review. 

 New Books 6-14 



MSS. Intended for publication and books, etc., intended 

 for review should be sent to the responsible editor, Prof. J. 

 UcKeeD Cattell, Garrison on Undson, X. Y. 



Subscriptionsand advertisements should be sent to Sciente, 

 41 N. Queen St., Lancaster, P«., or -11 East 49th St., New York. 



A DYNAMICAL HYPOTHESIS OF INHERIT- 

 ANCE (II.). 



The egg cannot be isotropic — as follows 

 from observation as well as experiment — in 

 the sense in which the word isotropy is used 

 by physicists of repute. If the egg is a dy- 

 namical sj'Stem it cannot be isotropic or ab- 

 solutely the same throughout, or along 

 every possible radius from its center, as is 

 proved by its reactions in respect to its sur- 



roundings. It may, however, be potentially 

 feolotropic in directions parallel to a certain 

 axis, as experiment has shown by separa- 

 ting the cells that result from segmentation 

 of the egg. Such fragments, if in excess of 

 a certain minimal size, will undergo a larval 

 development of apparently normal char- 

 acter. But this result is fatal to the ordi- 

 nary corpuscular hj-potheses, according to 

 which every futiu'e part is represented in 

 the chromosomes hy certain hjiiothetical 

 corpuscular germs. It has, indeed, been 

 shown by Loeb that larval development of 

 portions of an egg can go on whether the 

 divisions be equal or unequal or in any 

 radius. This seems to indicate that an egg 

 is not necessarily isoti-opic in the undivided 

 state, but that the moment that separation 

 of its mass has occurred there is a readjust- 

 ment of the relations and potentialities of 

 its molecules simulating that of the original 

 entire egg. The very definition of isotropy, 

 as given by one author (Lord Kelvin), 

 states that it may be assumed only of a 

 spherical mass of matter whose properties 

 are absolutely the same along every one of 

 the infinite number of radii drawn from its 

 center outward, and, as tested by any means 

 whatsoever, shows that such a conilition 

 cannot be assumed, on the gi-ound of obser- 

 vation alone, of any known egg. The con- 

 dition of the egg we must therefore also as- 

 sume from its known properties to be reolo- 

 tropic, or diflerent along every one of the 



