104 DISCOVERY REPORTS 



Biology. In Text-fig. 37 are shown the size-distribution and state of the gonads in all specimens, 

 adding together all material from different years. 



Only large specimens were present in December, January, February and April. Material collected 

 in May shows a number of very small specimens representing the new generation. The breeding 

 season probably occurs between the end of February and the beginning of May. This is confirmed by 

 the state of the gonads which are full from December until February in those animals large enough to 

 be mature. In July animals of a similar size have empty gonads, showing that these animals have 

 spawned. 



Distribution. Subantarctic (Falkland Islands to Tierra del Fuego). 



NUMBER OF 

 SPECIMENS 



JULY 5 



1 



JUNE 



MAY 



APRIL 



MARCH 



FEB 



JAN 



DEC 



I 



'If 



I 



I 



1 

 1 



I 



vttut\ 



□ 



NO GONADS 



GONADS 

 DEVELOPING 



GONADS 

 MATURE 



GONADS 

 SPAWNED 



"I ' 1 1 1 



1 2 3 4 5 6 



BODY LENGTH CM 



Text-fig. 37. Cnemidocarpa nordenskjoldi (Michaelsen) : Size distribution and condition of the gonads 



of specimens collected in different months. 





Cnemidocarpa drygalskii (Hartmeyer) (Text-fig. 36 B) 

 Styela drygalskii Hartmeyer, 191 1, p. 452, pi. 45, fig. 6, pi. 50, figs. 6-10. 



Occurrence. St. 187: Palmer Archipelago, 259-354 m - 



External appearance. The body is dorso-ventrally flattened into a low dome-shape, with a broad 

 base of attachment. A roughened surface is produced by the presence of many small raised plates on 

 the test. The colour is pale brown. 



Internal structure. The diagnostic characters of the species, and details of the 'Discovery' 

 specimens, have been given in the comparison with Cnemidocarpa nordenskjoldi (see Table 31). 



Remarks. I believe that this species, like the previous one, is best placed in the genus Cnemidocarpa, 



