1 66 NOTES AND COMMENTS [September 



(b) By fixing upon it in such a way as to destroy it ; 



(c) As a competitor for a limited food-supply, or for a 



limited amount of fixing space. 

 3. The biological conditions by which the organisms on any 

 particular patch of ground are influenced depend not only 

 upon the organisms living on that ground itself, but also 

 upon the nature and abundance of the organisms living upon 

 neighbouring grounds. 

 We have quoted the above analysis because it seems to us admir- 

 able, and indicative of the careful manner in which Mr. Allen has 

 dealt with his problem. And although the research has a less obvious 

 practical outcome than that on plateau-life, with which we have coupled 

 it, this justification is not awanting, for it helps towards an under- 

 standing of the local distribution of food-fishes. 



As Regards Protoplasm. 



Those acquainted with Trof. E. B. Wilson's work entitled " The Gell 

 in Development and Inheritance " will remember that he is no optimist, 

 and will not be surprised to find him saying in a more recent deliver- 

 ance (Science, x. 1899, pp. 33-45, 4 figs.): — "If we except certain 

 highly specialised structures, the hope of finding in visible protoplasmic 

 structure any approach to an understanding of its physiological activity 

 is growing more, instead of less, remote, and is giving way to a con- 

 viction that the way of progress lies rather in an appeal to the ultra- 

 microscopical organisation and to the chemical processes through which 

 this is expressed." He starts in his lecture with a familiar object — 

 the egg of the sea-urchin — and defines the problems suggested by it : 

 (1) What is the actual structure that gives the appearance of a mesh- 

 work ? (2) How faithfully does the preserved structure, as seen in 

 sections, reproduce that existing in life? (3) What is the relation of 

 the astral systems to it ? (4) What is the finer structure and origin 

 of the meshwork ? (5) Can this structure be taken as typical of all 

 protoplasm ; and if not, what is its relation to other forms of proto- 

 plasmic structure? And incidentally, still another interesting question 

 arises : Is it possible to identify any one of the three visible com- 

 ponents — granules, continuous substance, ground -substance — as the 

 living substance or protoplasm proper, as distinguished from a lifeless 

 metaplasm, and, if so, what are its structural relations ? 



To propose dogmatic answers to these questions would be at present 

 absurd, and Professor Wilson is of no such mood. He has, however, 

 specialised in cytological work, and his conclusions are therefore of 

 value to less intimately initiated workers. 



As to the nature of the meshwork he concludes that in the resting 



