ORTHOPTERAN SPERMATOGENESIS 663 



a later paper I hope to enter into this matter more fully, but for 

 the present I will merely indicate the facts relating to Orthop- 

 teran spermatogenesis which support this view. 



(1) There is the fact of greatest significance that in each cell 

 division they perpetuate themselves, and by a process suggestive 

 of the utmost accuracy and importance. The means for conserv- 

 ing the continuity of each chromosome is therefore clear. (2) 

 The result of the operation of this process is demonstrated by the 

 observation that not only does the individual animal show in 

 each of its cells the same series of elements but all the members 

 of the species, genus and even family, with few exceptions, have 

 it. The observed process and the results of its operation through 

 countless cell generations is thus demonstrated. Accordingly, 

 any one chromosome has the form, size and behavior which 

 characterize it for the reason that it is the direct material 

 descendent of a line, each member of which possessed these same 

 characteristics. 



It ought not to be necessary, in writing for biological readers, 

 to say that in making such a statement I do not in any sense 

 impute omnipotence, omniscience or immutability to the chromo- 

 somes. But the absurd lengths to which some opponents of 

 chromosome investigations have gone in attempting to break 

 down the facts regarding them perhaps make it desirable for me 

 to add that I have always considered the chromosomes as a part 

 of the organic mechanism, reacting to each other and to their 

 environment, as ail living substance must do in order to exist. 

 They neither make the organism nor are they made by it, but 

 they do perpetuate themselves and perform functions of vital 

 importance to each cell and to the entire organism. My position 

 in this matter is more fully outlined in a former paper ('08). 



In addition to these two facts regarding the reproduction of the 

 chromosomes there are others which speak strongly for their 

 individuality. These concern questions of organization and 

 behavior and will be referred to more at length throughout the 

 paper. At this point I will briefly mention them : (3) Constancy 

 in relation to the spindle fibers. In almost every case the attach- 



