724 



MEDUSAE OF THE WORLD. 



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

 gives off from 14 to 16 long, lateral branches vk'hich branch at their outer ends but do not 

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

 and end blindh'. 



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



In the character of its canal-systein this medusa is intermediate between Pol\orchis 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). 

 Spirocodon saltatrix^ Maas, 1909, .Abhandl. .\kad. W'issen., .Miinchen, 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 onl\- 12 mm. high and 5 min. wide, with high, slightly bulging sides and 

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

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

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



^^'''ll^^ 



Fig. 427. — Spirocodon saitairix. After Maas in Abhandl. Akad Wisst'n., Miinchen. 

 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. 



