724 



MEDUSA OF THE WORLD. 



tentacles, said to arise in several rows from the bell-margin. Each of the 4 radial-canals 

 gives oft from 14 to 16 long, lateral branches which branch at their outer ends but do not 

 anastomose. Many short, usually unbranched, centripetal canals arise from the ring-canal 

 and end blindly. 



A single specimen was obtained at Korsakoff, Saghalin Island, on September 19, 1906. 



In the character of its canal-system this medusa is intermediate between Polyofchis and 

 Spirocodon, but the bell-margin is simple, not cleft into lappets, and the tentacles are spaced 

 at equal distances apart around the margin. 



Spirocodon saltatrix Tilesius (see page 220, Vol. I). 

 SpirocoJon saltatrix, MAAS, 1909, Abhandl. Akad. Wissen., Munchen, Suppl. Bd. I, Abliandl. 8, p. 18, taf. z, fign. 10-13. 



Maas gives by far the best published description of this medusa and corrects several 

 errors of former students, especially in respect to the character of the gonads. 



When the bell is only 12 mm. high and 5 mm. wide, with high, slightly bulging sides and 

 dome-like apex, the gelatinous substance is thick, being thicker in the perradii than in the 

 8 adradii. The circular muscles of the subumbrella are entire. There are 8 clusters, each 

 with about 20 tapering tentacles. The stomach is a long, simple tube with 4 distinct lips 



FIG. 427. Spirocodon saitniri.v. After Maas in Abhandl. Akad Wissen., Munchen. 

 A, young medusa with small gonads and tentacles, still in 8 clusters. B, half- 

 grown medusa, showing one of the gonads. C, full-grown medusa, tentacles 

 and canals omitted to show the form of one of the^gonads. 



