Variations Aynong ScyphojneduscB. 579 



It was with these in mind that in securing material for my 

 investigations I endeavored to have it collected from points some- 

 what remote, yet in the same general region, and also from 

 environments so definite and yet distinctly different, as to afford 

 a means of estimating the probable effects traceable to direct and 

 determining factors. It was an unexpected bit of good fortune 

 that brought me into possession of material from an environment 

 apparently quite likely to afford just the desired conditions 

 suitable to a test. This was the occurrence of ephyrae of Aurelia 

 in considerable numbers in April, 1902, in a small more or less 

 isolated, and polluted pool, known at the "eel pond" located at 

 Woods Hole, and connected with the waters of the harbor by a 

 very small inlet, sufficient to admit tide-water daily. The pond 

 has served in some measure as a general dumping ground for 

 various waste and sewage from the village. 



From this pond I obtained 486 ephyrae, all quite young, and 

 many of which I was able to examine alive soon after their capture. 

 A few specimens were obtained from strobilating polyps kept in 

 aquaria where they thrived quite well for several weeks. 



A second series was obtained from Waquoit Bay, a large bay 

 opening directly into Vineyard Sound, and some ten miles east of 

 Woods Hole. This collection was made in April 1901, and 

 contained 1026 specimens. 



Still a third series was collected at Waquoit in 1904, numbering 

 about 1000. They were obtained in May, and were mostly in 

 process of metamorphosis into young medusae. 



In 1905 a collection of adults were obtained from somewhat 

 similar environments, one series, indeed, from Waquoit. The 

 other numbering about 200 — though on account of poor preserva- 

 tion only 129 were available for accurate study — were collected 

 at the mouth of the Acushnet River, in New Bedford harbor. 

 This environment was as unlike that of Waquoit as is the latter 

 from the *'eel pond." New Bedford harbor receives the sewage 

 and other pollution of the city, as well as the constant influx of 

 fresh water from the river, thus constituting an environment at 

 once more or less local and peculiar, being about 17 miles west 

 of Woods Hole and therefore nearly thirty miles from Waquoit. 



Observations made upon the ephyrae of Cyanea during their 

 development, a brief account of which has been given elsewhere, 

 in which considerable variation was discovered and found to be 



