432 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. 45. 



VERTICAL DISTRIBUTION. 



Table 4 exhibits the depth range of the species as indicated by the 

 data accompanying this collection. 



TABLE 4. 



Since practically all the specimens collected by dredging and accom- 

 panied with data as to depth are collections made by the Bureau of 

 Fisheries steamer Albatross, an examination of this vessel's opera- 

 tions with reference to the ascidians obtained has been made. Town- 

 send's ''Dredging and Other Records, etc." (1901) makes such an 

 examination practicable. 



The total number of hauls contained in this list as made since the 

 Albatross entered the waters of the Pacific in 1888, and which belong 

 to areas from which ascidians covered by this report were derived, 

 is 676. 



The depths at which these hauls were made is shown in Table 5. 



