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Canadian Record of Science. 



arrangement, and has represented it in his figures^ (see 

 also Fig. 6). It is evident that in a structure like this a 

 transverse or oblique section will show truncated portions 

 of the larger tubes apparently intermixed with others 

 much finer and not continuous with them, except very 



^^^o o ^ o ol 



r-> ^ O /^^ Q 



Fig. 



-Cross section of minute tubuli, about 5 microms. in diameter* 

 (Magnified.) 



rarely. Good specimens and many slices and decalcified 

 portions are necessary to understand the arrangement. 

 This consideration alone I think entirely invalidates the 



♦, > 





Fig. 8. — Cross section of similar tubuli, more highly magnified, and 

 showing granular character of the test. (From camera tracings.) 



criticisms of Mobius, and renders his large costly figures 

 of little value, though his memoir is, as I have elsewhere 

 shown, liable to other and fatal objections.^ 



1 Ann. and Mag. Nat. Hist, .ser. 4, xiii, p. 450, tigs. 3, 4. 



2 Museum Memoir, pp. 50 et seq. 



