1913] Michael: Saijilia calif (irnica f nun Sail Di('(jo Ihyion 10 



11.0 per cent in animals between 12 and 14 mm 



8.8 per cent in animals between 14 and 16 mm 



7.2 per cent in animals between 16 and 18 mm 



7.8 per cent in animals between 18 and 20 mm 



7.9 per cent in animals between 20 and 22 mm 

 8.0 per cent in animals between 22 and 24 mm 

 8.2 per cent in animals between 24 and 26 mm 



Interv.\l from Posterior Pin to Seminal Vesicle. — In the 

 100 specimens measured in table 1. all stages in the maturity of 

 seminal vesicle are recorded, from an invisible and barely visible 

 condition in animals 12 to 14 mm. in length to complete maturity 

 in the larger animals. In some species an interval exists 

 between posterior fin and vesicle during the undeveloped stages 

 of the vesicle which entirely disappears when the vesicles attain 

 maturity. I was therefore led to expect that a negative correla- 

 tion would be found in 8. californica between the proportional 

 length of this interval and length of animal. Imagine my .sur- 

 prise when table 5 was constructed and a tendency toward 

 positive correlation revealed. 



Correlation between Length of Animal and Proportional Length op 

 Interval between Posterior Fin and Seminal Vesicle 



Inspection of this table shows that, with two exceptions, the 

 larger intervals are found only in the larger animals. Further- 

 more, inasmuch as the proportion of the population (see numbei-s 



