\ I.i:. 





the vesicle ha> n\v become a solid struct i ii.-. uhich, as the lens . 

 furni>he> tin- foundation of the l.-n^ of tin- adult. 



Tin' J art In r in<-,','uttf 'in tin fM '/ //< /WW W an apporitional yr< 

 Around i lift- mini nri> ii'-w 1--I 1 1 ic h are arranged 



parallel t<> the surface of the organ and are united . These 



lit- in layer> one over another, which in lenses may be 



detached like fchf in ... ,;,,. .\:i i; 



extend from tlu- anterior t< tlu- posterior -uriace, u here t heir ends 

 inert one another along regular lines, uhirli in the n. i the 



new-horn animal liavt? the form of t v. 



' :iil| it- th.- 



>-ralli (1 xturs of (/> 



peculiarity that the rays of 

 the anterior face alternate 



with those of the ]>< sterinr 

 lace, so that the three rays 

 of one star halve the .^.aces 

 between the three rays of the 



other. 



In the adult the lii_ f uie 

 uiore complicated, 

 because lateral rays ari 

 each of the three chief r 



How liave the newly de- 



d fibre- been formed I 



Their origin is ultimately to 

 be referred to the !: 

 theliuin of the front Miri'aci* 

 of the organ. In these cells 

 of nuclear division can 



Fig. 268. Diagram of the arrangement of the 



leni-flbres. 

 One ees the opposite positions of the a 



and the posterior </w() stars of the len. 



If, Course of the leiis-fibres on the anterior 



surface of the lens ami 



the anterior star of the lens ; //", oout . 



of the same librea to the posteiior star uu the 



fie(p.ently l>e olerveil even in late i< ..\el(jiuent. The 



which re.-nlt from di\ision >ei\e to n -| M \\liii-h gix)w out 



into lens -iibn-s, and are placed upon the already formed la 

 The new formation takes place only at the equator of the l-n> 

 (ti-T. -(n) in the zone of tran>itin (/') i>r-u>i>ly de>crilied. \\ 

 in the adult as well as in the recently horn animal, the cubical 

 epithelial cells gradually merge into cylindrical and fibrous elem< 

 as one can conviiu-e himself from an\ j tlirected Mvtion. 



In the adult, as is well known, there -xi>t no sjuvial provision- 

 (//>' nutrition f the leiis, which, aflei- attainint: full si/.e. i> not much 

 altered, and certainly undergoes only a slight meta>ta>i>. With the 

 embryo it is otherwise. Here a more active growth tes a 



