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Bashford Dean Memorial Volume 



males (1320 mm. or 52 in.) we see that the females still average larger than the males, and 

 that the difference is greater than in the preceding case. The average female is 259 mm. 

 or 10.25 in. longer than the average male, based on the measurements of the 14 males and 

 33 females in our tables. The average female is 1.2 times longer than the average male. 



That the female of this fish should be larger than the male is in keeping with the 

 general rule in fishes. However, in Chlamydoselachus there seems to be a particular 

 reason found in its method of reproduction (viviparity) ; for the female has to build up the 

 enormous eggs and then accommodate and incubate them within her slender body during 

 the many months before the young are born. For an idea of the capacity required for this 

 see Text'figures 2 and 5 and Figure 5, plate II, showing dissected and unopened females 

 respectively. 



TABLE VI 

 DETAILED COMPARATIVE MEASUREMENTS OF CHLAMYDOSELACHUS AHGUIHEUS* 



The smallest fish are two females of 610 and 845 mm. (24 and 33.25 in.). The smallest 

 male is 920 mm. (36.25 in.) long. The only other unusually short specimen is one of un' 

 known sex measuring 950 mm. (37-4 in.). All other fish listed are above 1000 mm. in 

 length. The largest of the ''unknown" class measures 1600 mm. (63 in.). The largest 

 male is 1650 mm. (65 in.). However, there are 10 females larger than this fish. Of the 

 three largest females, one (Spain) is 1860 mm. (73.25 in.) long, another (Norway) is 1910 



•Measurements in millimeters. 



