294 Southern Cross. 



XVIII. ACTINIAE. 



WITH AN ACCOUNT OF THEIR PECULIAR 

 BROOD CHAMBERS. 



By JOSEPH A. CLUBB, M.Sc, 

 (Plates XLVIIL-LII.) 



A SMALL collection of Actinians was made by the ' Southern Cross ' 

 Expedition of 1899-1900. All the specimens were collected oft' 

 Cape Adare, South Victoria Land, the winter quarters of the 

 expedition, and were dredged at a depth of from 20 to 30 fathoms, in 

 water having a temperature ranging from 28*8° Fahr. in November, 

 1899, to 29 "2° Fahr. in January, 1900. The preservatives used were 

 formaline and spirit, and the specimens in the former fluid were in 

 better preservation than in the latter, where, owing to inefficient 

 corks to the bottles, the volatile spirit had evaporated, leaving a fluid 

 which could not be called preservative. 



Although there are upwards of sixty specimens, it is somewhat 

 remarkable that there appear to be but two closely allied species, and, 

 as the females of both possess special brood chambers, they are of great 

 biological interest. I wish here to record my thanks to Professor 

 Jeffrey Bell for placing the collection in my hands, and thus 

 affording me the opportunity of investigating them, for the large 

 number of specimens has enabled me to work out in some detail the 

 appearance and structure of these remarkable chambers, which are 

 apparently peculiar to Arctic and Antarctic species. As the brood 

 chambers are almost identical in both species, I have appended this 

 part of the work after the description of the species. 



The two species belong to the family Bunodactidce,^ and, while 

 possessing the typical hexamerous arrangement of mesenteries and 



^ I have adopted the suggestion of Prof. Verrill (7, II., p. 42) that, as the name 

 Bunodes is preoccuiiied for a genus of Eurypteroids, the actinian genus Bunodes 

 should be changed to Bunodadis, and in accordance with the usual custom the 

 family name Bunodidse becomes buitodadidiv. 



