694 BECORD OF CURRENT RESEARCHES RELATING TO 



lias still to be investigated ; but whatever the result arrived at, the 

 generality of the principle of association will not be at all invalidated, 

 for if in this case simple individualities never existed, we should have 

 to compare the Mollusca and the Vertebrata with the primordial 

 individuals, the combinations of which produced the other types. How 

 did these individuals themselves originate ? 



The Hydrce and other analogous organisms, the author thinks, 

 furnish the answer ; and after dealing with these, he says : — 



" Thus, even if it be shown that the Vertebrata and Mollusca do 

 not result from the fusion of simpler beings once capable of an inde- 

 pendent existence, they will not, any the less, be colonies of cells. 

 The ' law of association ' will consequently lose none of its generality, 

 and will remain the fundamental law of the development of the 

 animal kingdom, including and governing those laivs of grotdli, organic 

 repetition, and economy, that for a long time past have engaged the 

 attention of physiologists," while it explains hitherto inexplicable 

 homologies. 



The author then passes to the consideration of protoplasm, and 

 from the incapacity of the protoplasmic masses to exceed a certain 

 size, draws the conclusion that all creatures that exceed this size 

 must be formed of several distinct masses of protoplasm — that is, are 

 colonies. " Thus the generality of the law of association is shown to 

 be a consequence of one of the fundamental properties of protoplasm." 



Degeneration.* — Professor E. Eay Lankester has published, as a 

 separate volume, the lecture which he delivered on this subject at the 

 British Association meeting in 1879. 



In attempting to reconstruct the pedigree of the animal kingdom, 

 and so to exhibit correctly the genetic relationships of all existing 

 forms of animals, naturalists have hitherto assumed that the process of 

 natural selection and survival of the fittest has invariably acted so as 

 either to improve and elaborate the structure of all the organisms sub- 

 ject to it, or else has left them unchanged, exactly fitted to their condi- 

 tions, maintained, as it were, in a state of balance. It has been held 

 that there have been some six or seven great lines of descent — main 

 branches of the pedigree — such as those of the vertebrates, molluscs, 

 insects, star-fishes, and so on ; and that along each of these lines there 

 has been always and continuously a progress — a change in the 

 direction of greater elaboration. 



Each of these great branches of the family tree is held to be 

 independent. They all branch ofi" nearly simultaneously from the 

 main trunk. The animal forms constituting the series in each of 

 these branches are supposed to gradually increase in elaboration of 

 structure as we pass upwards from the main trunk of origin and climb 

 further and fui-ther towards the youngest, most recent twigs. New 

 organs have, it is supposed, been gradually developed in each series, 

 giving their possessors great power, enabling them to cope more 

 successfully with others in that struggle for existence in virtue of 



* ' Degeneration : a chapter in Darwinism.' . (8vo, London, 1880.) 



