152 THREE CRUISES OF THE “BLAKE.” 
sive distribution in the Atlantic, and is a common Caribbean 
species. 
One of the most elegant of the West Indian corals is the pure 
white Amphihelia rostrata (Fig. 473), which must have spread 
Fig. 473. — Amphihelia rostrata. 1. 
at least twelve centimetres. It has been dredged to a depth of 
nearly 900 fathoms. Axohelia mirabilis (Fig. 474) is very 
common in the Caribbean, and is rather variable. Many spe- 
cimens are deformed by Barnacles occupying the end of the 
branches, which soon become entirely covered by the coral, 
leaving only a small opening. As representatives of one of 
the most natural of the families of corals, we may mention 
Thecopsammia socialis (Fig. 475) and 7. tintinnabulum, of 
which the living polyp is of a handsome pinkish orange color. 
