LKITO.MKDrs.K -< T VIKHIA. DK 'H< )T< iM I \. 



223 



each give rise at their middle points to 2 opposite side branches. These main canals and their 

 2 branches each end in 5 to 7 terminal branches, and thus about 70 vessels reach the ring- 

 canal. Gonads spindle-shaped, on terminal branches of the canals near the ring-canal. 

 Color (?) Found off Azores, Atlantic Ocean. Distinguished by its large number of 

 marginal clubs and few tentacles. Is it only a variety of ('111-1,11/1 ciirisochrntnii 1'eron ( ?) 



Genus DICHOTOMIA Brooks, 1903. 



Dichotomia, BROOKS, 1903, Proc. American Philosophical Society, Philadelphia, vol. 42, p. i i . - MA*S, 1904, Siuungsber. math.- 

 phys. Klasse kgl. Bayer. Akad. dcr Wisscnschaften, Bd. 34, Heft 3. 



CKNKRR CHARACTERS. 



Berenicidae with 4 main radial-canals which divide dichotomously 2 or more times and 

 open into the circular vessel by 16, 32, or more distal branches. Tentacles of t\\<> suits 

 hollow ones and solid ones all arising from bell-margin. Mouth simple without prominent 

 lips. The gonad encircles the stomach and extends outward over the radial-canals and their 

 branches. 



115. 



116. 



Fie,. 115. Curifria huxltyi, after Haeckel, 1879. 



Flc;. lib. Dichotomia cannoides, after Brooks, in Proc. American Philosoph. Soc., vol. 42. 



A, young medusa. B, adult medusa. C, model showing arrangement of radial-canals. 



The type species is Dicliutniniu < annoides, described by Brooks from the Bahama Islands. 

 This is the only known species. 



Dichotomia cannoides Brooks. 



Dichotomia cannoides, BROOKS, 1903, Proc. American Philosophical Soc. Philadelphia, vol. 42, No. 172, p. 12, plate i, 3 figs. 

 MAAS, 1904, Sitzungsbcr. math.-phys. Klasse kgl. Bayer. Akad. der \VisM-nschaft., Bd. 34, p. 438. 



Bell about 8 mm. high and 6 mm. wide, subcylindrical, and with conical apex. The 4 

 main radial-canals do not arise independently and directly from aboral end of stomach, but in 

 pairs from the ends of a short transverse canal, so that the only planes which divide the medusa 

 into symmetrical halves are the two primary interradial planes, \\hen thus divided each halt 

 is bilaterally symmetrical, and the halves are reversed copies of each other (fig. i i<' i . The 

 4 primary radial-canals branch dichotomously at least 3 times, so that 32 terminal branches 



