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4 
Variation in Aurelia Aurita 
Thirteen Tentaculocysts. {Five specimens.) 
Perradial 3.2.2.2. 3.3.1.2. 
Interradial 1.1.1.1. 1.1.1.1. (Diagram II ) 
Two specimens with five extra perradial tentaculocysts. 
Perradial 2.2.2.2. 
Interradial 2.1.1.1. 
One specimen with four extra perradial tentaculocysts and one extra inter- 
radial. 
Two specimens with more than the normal number of genital sacs. 
One with six genital sacs and six oral arms. 
One with five genital sacs and five oral arms. 
Fuurteev Tentaculocysts. {One specimen.) 
This specimen has eight genital sacs and eight oral arms. 
Fifteen Tentaculocysts. {One specimen.) 
Perradial 2.1.3.3. 
Interradial 1.2.1.2. 
There are five extra perradial and two extra interradial tentaculocysts. 
Numerical Variation of the Genital Sacs of 3000 Adults taken in 1898. 
{Series A and B.) 
Previous accounts by other writers on the Variation of Aurelia have been 
mostly confined to the variation of the genital sacs, and numerous illustrations 
have been published. (Ballowitz, 1899.) 
In the Ephyra stage the genital sacs are not present, but their position and 
number are marked by the bundles of gastric filaments. Normally there are four 
interradial bundles of filaments. The gastric filaments are not figured in the 
diagi'ams of the adults. They are always situated along the inner side of the 
gonads. 
In the small Ephyrae an increase or deciease in the number of gastric filaments 
indicates that the specimen will probably have an increase or decrease in the 
number of genital sacs, as the numbers of bundles and gonads are correlated. 
It is not however easy to count the number of bundles of gastric filaments in 
the small Ephyrae, especially when there are indications of an increase, as then 
owing to the closeness of the bundles they form occasionally an unbroken ring. 
When an Ephyra has developed into the adult form and the gonads begin to 
appear, and also the genital sacs, then any variation in the number of gonads 
or genital sacs is easily seen. 
