274 



NATURE 



[October 27, 192 1 



ances in position in some combinations, it is probable 

 that a definite and approximately equal share of space 

 must be accorded to each electron. The approxi- 

 mately rectilinear curve points to this fact. Both 

 properties, however, differ somewhat in different 

 combinations, so that some slight modification is to 

 be understood. It is, however, sufficiently interesting 

 to be able to trace such a relation when it is con- 

 sidered that neither the atomic volumes nor refrac- 

 tions can be directly measured, but are derived con- 

 stants. 



Some of the variations seem to point to variable 

 relations with the ethereal medium. Negative 

 anomalies, for example, are at present incompre- 

 hensible, the whole of the atomic refractions o£, say, 

 oxygen in P(OEt),, for example, disappearing entirely. 

 Some of the ^er saltum changes are equally difficult 

 to explain. The periodic relationship between the 

 elements points rather to a spiral arrangement (under- 

 stood in a solid sense) ^ of the electrons than to a 

 series of rings. This arrangement is due to the fact 

 that the spiral is one of the natural modes of motion 

 of the aether and discrete particles immersed in it. 



based on products, whilst the additive cumulative 

 factor is evident ; still, the relation is interesting. The 

 next homologuc after CI is Br (red liquid). There 

 is, however, a large gap between the two. Instead 

 of an easily condensible yellow-red vapour at 55, by 

 some twist we get a metal. There is a similar dis- 

 parity between Br and I. Gervaise Le Bas. 

 6 Springfield Crescent, St. Heliers, Jersey. 



20 



i 



Vj /O 



I 



10 



20 



30 



The Atomic Volumes 



Flfi. I. — A relation between the atomic volumes and the atomic refractivities 



This is shown in the case of spiral nebulae. The 

 vortex is another condition. Gradual disintegration 

 of the atoms is thus more easily understood, and 

 devolution is reversed evolution. 



Up to the present the charge on the electron is 

 regarded as static, but the existence of magnetic pro- 

 perties suggests rotations of electricity on the material 

 particles. This would result in a magnetic flux. It, 

 however, seems to be impossible to distinguish the 

 charges within the atom. 



Note. — A numerical relation with the atomic masses 

 suggests itself. w = 3r. xF, F being a factor probably 

 representing concentration of matter (atomic density). 

 »« = 6oXF 60 ^o*" ^•^■ 



- =F(2, 2, 3, 3) not for first series except for C. 

 bo 



CI 6x3x2= 36 



, Mn 8-8 X 3x2= 52-8 (55) 

 Br 88x3x3= 79*2 (79"6) 

 I i3-9X3X3=i25i (126). 

 F- diminishes from group 7 10 4 and increases 

 differently in the groups. This relation is, however, 



* A spherical tourbouillon with a vortical centre and a peripheral 

 rotation (model slip-knot). 



NO. 2713, VOL. 108] 



Hybridity and the Evolution of Species. 



As the author of the "Theory of Evolution by 

 Means of Hybridisation," I am naturally much in- 

 terested in the recent papers by Dr. Harrison and Miss 

 Blackburn, which proved beyond any reasonable doubt 

 that most British rose-species are of hjbrid origin, 

 though this was not suspected. The authors based 

 their conclusion that hybridity is one of the prime 

 factors in the evolution of species, if not the only 

 one, on their cytological results, which agree with 

 those of Tackholm on a much larger number of rose- 

 species from all parts of the world. The reviewer of 

 their papers in Nature of September 15, p. 99, does 

 full justice to the importance of 

 these results, and directs attention 

 to Jeffrey's work tending to show 

 that the presence of "bad pollen "^ 

 is proof of a hybrid origin — a view 

 much strengthened by Brainerd 

 and Petersen's study of the New 

 England Ruhi (Vermont Agric. 

 Expt. Sta. Bull. No. 217), in the 

 course of which they find much 

 hybridisation and no forms with 

 entirely good pollen. 



To this view the reviewer takes 

 exception. That "bad pollen"' 

 is unsafe as a criterion of 

 hybriditv is shown, he says, how- 

 ever, by other results. As such he 

 considers the fact that isolated 

 species, such as the Californian 

 Trillium giganteutn, the nearest 

 relative of which is in the Eastern 

 States, possess a certain amount 

 of bad pollen. I am sorry to say 

 that I fail to see the bearing of a 

 now isolated habitat on the 

 problem in question. I sup- 

 pose that the reviewer will 

 agree with me that the origin of Oenothera biennis, 

 which for several centuries has been a feature of the 

 flora of the dunes in manv European countries 

 originated elsewhere than in Europe ; so why should 

 Trillium giganteum, and Dirca occidentalis and 

 Scoliopus Bigelovii, the other two species with bad 

 pollen which he quotes as proof of his contention, have 

 originated at the spots they now occupy? And if 

 they originated somewhere else, the argument against 

 their possible origin by crossing does not hold good. 

 Velp, Holland, October 4. J. P. Lotsy. 



40 



It is perhaps only natural that Dr. Lotsy should 

 take a special view of any facts that bear on his 

 theory of evolution by hybridisation, but in the above 

 letter he is clearly begging the question. In the 

 article on British roses and hybridity to which he 

 refers it was pointed out that the original authors did M 

 not consider all British roses to be hybrids, but ^ 

 looked upon the diploid forms and the Pimpinelli- 

 foliae as pure species. In such cases as Trillium, 

 Dirca, and Scoliopus, it is not sufficient for him to 

 suggest that they must be hybrids merely because they 

 have bad pollen. The fact, previously cited, that 



