118 
DEPTH. 
Ch. IV. 
than those mentioned in this note ; for instance, Caryophyllia, 
down to at least 1,000 fathoms (The Depths of the Sea, pp. 28, 431). 
True corals referable to the Madreporaria are not very abundant 
in deep water. According to Mr. Moseley’s report, about ten genera 
reach a depth of 1,000 fathoms ; four genera are found at 1,500 
tathoms ; and a single species extends practically through all depths, 
ranging from 30 tc 2,900 fathoms. Challenger Reports, vol. ii. 
(Zoology), ‘ On Corals,’ pp. 132, 133. Seo also Reports, vol. xvi., 
‘ Ou Reef-Corals,’ p. 35. 
