THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 



BAL3SNOPTERA MU3CULUS (L.). NEWFOUNDLAND. FCETUSES. 1901. 



155 



Of the specimens obtained at the same station in 1900, the following females 

 contained foetuses: 



BALJENOPTERA MUSCULUS (L.). NEWFOUNDLAND. . FOETUSES, 1900. 



From the foregoing data, it appears that the minimum length at maturity is 

 72 feet for females. Excluding all below that length, the average for southern 

 Newfoundland, fourteen specimens, is 74 ft. 8 in. 



For the Norwegian specimens, employing the same minimum, we obtain (24 

 specimens) 79 ft. 3 in. as the average total length. 



It is to be observed in this connection that the Longniddry whale, which was 

 78 ft. 9 in. long from the tip of the lower jaw to the notch of the flukes, and 

 contained a foetus, is classed by Sir Win. Turner (91, 203) as " adolescent," in ac- 

 cordance with Flower's system (45, 385), based on the condition of the epiphy- 

 ses of the bones. It is well known that in many species of mammals offspring 

 are produced before the skeleton of the parent is completely ossified, but it may 

 perhaps be questioned whether in whales the total length increases materially after 

 sexual maturity. 



The condition of the bones cannot be ascertained usually at a whaling station, 

 where the carcasses are towed away as soon as the blubber is stripped off. It is 

 probable, however, that the size at which sexual maturity is attained is quite as con- 

 stant as the size at which the skeleton is completely ossified, so that averages based 

 on specimens known to be sexually mature may be regarded as reliable and useful. 

 Under the ordinary conditions of observation this is not as readily ascertained for 

 males as for females. As the males in this genus are smaller than the females, we 

 shall have too high an average for the former by excluding all individuals below 

 the length of the latter at sexual maturity. The amount, however, is not likely to 

 be large and may be neglected. 



For males 72 feet long and above, the average of the specimens measured by 

 myself at Balena station, Newfoundland, in 1901, is 72 ft. 4 in. (2 specimens). 

 Including the specimens taken the previous year at the same station, the average 

 is 75 ft. 1 in. (19 specimens). For the Norwegian males cited by Cocks, the 

 average is 77 ft. 7^ in. (27 specimens). The following table suras up these various 

 statistics : 



