226 



Mr. E. Shann on the Life-history and 



have survived till the following summer is problematical ; 

 but it is possible that comparative freedom from competition 

 and from the depredations of their enemies, due to their 

 estuarine environment, allow these forms to enjoy a longer 

 life than their neighbours in the sea. It may be added that 

 a specimen of O. minutus measuring 85 mm., the largest in 

 the collection, was captured in the waters of the Tay. There 

 is no record of the date of capture of the latter ; but it was 

 found among a shoal of sprats. There is also another large 

 specimen, date and locality unknown, which measures 82 mm. 



Table 1.— St. Andrews. 



