Grorcth Infcgration 103 



of twenty ca])sule.s from the bases, niiddK- |)orHons, and dis- 

 tal ends, respectively, of six such stalks. The weights given 



Number of Seeds Av. Wt. per Seed 



950 .0009.0 



733 .00088 



525 .000()3 



This mere glance at an exceedingly common phenomenon 

 in living nature must suffice for the present. 



Justification for Bringing All These Phenomena Under One 



Head 



Probably about the first question that most persons would 

 raise concerning what we have presented would be as to how 

 far the series dealt with have anything to do with one an- 

 other. Especially, we may apprehend, would most biologists 

 question the justifiability of bringing together the meristic 

 phenomena in animals and the repetition of parts in plants. 

 If such a collocation of phenomena must be justified on the 

 basis of known causal factors, then undoubtedly is justifica- 

 tion impossible in the present state of knowledge. But justi- 

 fication of this sort is not called for by the point now oc- 

 cupying us. What concerns us at present is the quite for- 

 mal fact that when any lot of homonymous objects fall into 

 a quantitatively graded series the members of that series 

 liave a fixed relation to the series as a whole. They n\\- not 

 interchangeable with one another. Kach is a function, 

 mathematically speaking, of its set or series. Vertibra /;/ 

 of the python's skeleton, myotome ni of the amphloxus Ixxly, 

 tube-foot 7n of the starfish arm, branchlet in of the ascidian 

 tentacle, leaflet m of the vetch leaf or of the redwood shoot, 

 seed-vessel m of Frasera, seed-lot m of the mustard plant, 

 and m, or any other member you choose from any other 



