GENERAL BIOLOGY 



757 



in three groups: (i) the large ones, (2) an inter- 

 and (3) the small ones or fry, and when fishing 



2 cf 



be classified 

 mediate group 

 we will very seldom be un- 

 certain as to which group 

 we may refer the fishes 

 captured. It is impossible 

 to apply the rule to both 

 sexes, but the males seem 

 on the average to be 

 somewhat smaller than 

 the females, and also less 

 numerous. Among the 

 larger sizes of the blen- 

 nies, the longest ones 

 seem to be sparingly re- 

 presented. Notwithstand- 

 ing all my exertions in 

 various localities, I have 

 never been able at this 

 time of the year (summer) 

 to find blennies of less 

 length than the ones re- 

 corded under the head of 

 fry, that is, about 3 to 4 

 inches. As the fry, when 

 born, are actually ij inch 

 long, I cannot doubt that 

 the group of small blennies, 

 which at this time of the 

 year differ so considerably 

 in size from the large 

 ones, really are the fry of 

 the year, which during the 

 last six months have grown 

 to this size, that is, have 

 added a couple of inches 

 to their length. It appears 

 equally natural to consider 

 the intermediate group of 

 blennies, between 6 and 8 

 inches, as the fry of the previous year. The direct conse- 

 quence is that all the large blennies between 10 and 12 inches 

 are of an age exceeding one year and a half by one year at 



Fig. 55: 



-Petersen's Measurements of 



ZOARCES VI VI PAR us. 



