588 'PEOF. W. A. HERDMAiS's EEVISED 



This genus contains the single ' Challenger ' specieswas Cory- 

 cidia Suhni, Herdmau, of which specimens were obtained in tlie 

 South Pacific from a depth of 21G0 fms., and in the Antarctic 

 from a depth of 1375 fms. 



CoBELLA, Alder Sf HancocJc, 1870, 



Body attached, occasionally free, sessile. Branchial aperture 

 8-lohed, atrial 6-lobed. 



Test gelatinous or cartilaginous, but soft and semitransparent. 



Branchial sac with no papillae on its internal longitudinal bars. 

 Stigmata curved and placed in the walls of regularly arranged 

 infundibula ; interstigmatic vessels spirally coiled. 



Dorsal lamina repre^iented by lauguets. 



Tentacles simple. 



Alimentary canal on the right side of the branchial sac. 



Gonads forming a network round the median part of the in- 

 testine. 



The species of Corella are as follows : — 



/Atrial aperture anterior 1 



[Atrial aperture dorsal 2 



(Atrial aperture placed on a very long projection. 

 6'. larvcsformis, Hanc. (N.W. Eur.) 

 Atrial aperture sessile, or on a short siphon 3 



r Musculature strong on left side... C. parallelogramma, O.F.M. (N.W. 

 3 \ Musculature very weak on both sides. [Eur., Med.) 



[ C. minuta, Traust. (W. Ind.) 



r Anterior end wide, atrial aperture not far from branchial. 

 2 \ C. ovata, Hanc. (N.W. Eur.) 



[ Anterior end narrow, atrial aperture distant from branchial 4 



^ [Tentacles of more than one size 5 



[ Tentacles all of one size . , C. japonica, Herdm. (Pac, Mai.) 



f- [Tentacles 50 6 



[Tentacles over 100 C. novarcB, v. Dr. (Ind. O.) 



{Tentacles of 2 sizes, dorsal tubercle horseshoe-shaped. 

 C. eumyota, Traust. (S. Atl.) 

 Tentacles of 3 sizes, dorsal tubercle semilunar. 

 C. horealis, Traust. (Arct.) 



Subfamily HTPOBTiHiiiirji;, Herdman, 1882. 

 Body pedunculated, fixed. Apertures not lobed. 

 Test gelatinous or cartilaginous. 



Branchial sac with no internal longitudinal bars. Stigmata 

 small and irregular. 



Viscera on dorsal edge of branchial sac. 



This group contains the single genus Sypobythius. 



