Sir W. Daicson — The Animal Nature of Eozobiu 547 



the lamina3, and proceed at first almost horizontally, dividing into 

 smaller branches, which ultimately give oif brushes of minute 

 tuhuli running nearly at right angles to the surfaces of the lamina, 

 and forming the extremely fine tubulation which Dr. Carpenter 

 regarded as the proper wall. In my earlier description I did not 

 distinguish this from the canal-system, with which its tabuli are 



Fig. 7. — Cross section of minute tubuli, about 5 microms. in diameter, (Magnified.) 



inwardly continuous ; Dr. Carpenter, however, understood this ar- 

 rangement, 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, 



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

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



except very rarely. Good specimens and many slices and decalci- 

 fied portions are necessary to understand the arrangement. This 

 consideration alone I think entirely invalidates the criticisms of 

 Mobius, and renders his large and costly figures of little value, 

 though his memoir is, as I have elsewhere shown, liable to other 

 and fatal objections.- 



It has been pi-etended that the veins of chrysotile, when parallel 

 to the laminee, cannot be distinguished from the minute tubuli 

 terminating on the surfaces of the laminee. I feel confident, 



' Ann. and Mag. Nat. Hist., ser. 4, xiii, p. 456, figs. 3, 4. 

 * Museum Memoir, pp. o^d et seq. 



