NARRATIVE OF THE CRUISE. 
525 
“ Plioberus, a genus named by Professor A. Milne-Edwards, was first taken by the 
Challenger in about 500 fathoms of water in the West Indies ; it is nearly allied to the 
genus Nephrops, which lives at no very great depth, and it grows to a considerable 
Fig 184 . — Thaumastocheles zaleuca, Sulim ; male, natural size. From 450 fathoms, off Sombrero, West Indies. 
size, the Challenger specimen being eight inches in length, and that taken in the 
‘ Blake ’ expedition being a little larger ; the ophthalmopoda are reduced to the smallest 
dimensions, and the eye to a rudimentary condition. 
