29 



Table imd Tables 1 and 2); they canuot be distinguished by Ihe measuremeut- 

 method as a special group trom the glass-eels before the month of July; so far, 

 the desiguations O and I group are not quite correet until that time, and it is 

 only by the ditfereuce in shape that vve can separate these years groups. 



Table 7. 



Growth o£ the I Group from May — September 1906. In columns 3 and 4 the II. Group 



is indicated. 



cm. 



25 



24 



23 



22 



21 



20 



19 



18 



17 



16 



15 



14 



13 



12 



11 



10 



9 



8 



7 



6 



5 



4 



3 



2 



1 



"I, 1906. 



1 

 1 



3 

 3 



1 

 4 



10 

 86 

 132 

 36 

 gla.ss-eels ^= O 

 group not in- 

 cluded in the 

 Table. 



I 



, 1906. 



14 

 17 

 17 

 46 

 84 



119 (25) I 

 34 (94) 



(1) 



The figures 



in hrackets 



give the num- 



ber of 



eels. 



O 



Table 7 shows the growth of the I group in the course of the summer ; 

 as specimens of the O, II and III groups are iucluded here, I have marked their 

 maxima vvith Roman figures so that they may easily be distinguished from oue 

 another. — By following the figure I from the middle of May to the end of 

 September \ve readily observe, that the growth is first detected ou July Uth and 

 that the maximum of the group moves from 8 to ca. 13 cm. during a whole 

 growth-period, which gives therefore a growth of ca. 5 cm. for the majority 

 of this year's group in the course of the summer, whilst its limits may be 

 placed at ca. OYj— 17 cm. at the time wheu the growth ceases. In the next 

 spring we meet it at the same size under the designation of II group; see Table 7 



