342 



Nephtys margaritdcea. 



appendage of the same character at its base, a small cirrus, 

 and an elongate branchial filament, curved like a reaping 

 hook ; the setigerous processes obtuse, broad, shorter than 

 the lamellae ; the inner armed with a row of long, and the 

 outer with a row of short, bristles : ventral branch much like 

 the dorsal ; the lamellae larger, with a small cirrus at its base. 

 Bristles dusky, longer than the processes, very slender, seta- 

 ceous, smooth, un- 

 jointed, each of the 

 longer series with 

 an acute retractile 

 brown spine in their 

 centre : the short 

 bristles look as if 

 they were abruptly 

 broken off; but they 

 are uniform on all 

 the feet, and appear 

 to be pointed under 

 the microscope. Anus 

 terminal, superior ; 

 the segment small, 

 apodal, terminated 

 with a slender fila- 

 ment or style. 



This worm is re- 

 markable for the 

 splendour of its co- 

 lour, which is exactly 

 similar to that of 

 mother-of-pearl; but 

 the silvery lustre is 

 almost confined to a 

 space down the back 

 and belly, for the 

 sides and feet are of 

 a yellowish hue, the 

 inner base of the feet 

 reddish, and the 

 bristles dusky. When 

 the foot is removed, 

 and placed under a 

 magnifier, it has a 

 sort of resemblance 



Nephtys margaritacea : a, the worm of the natural size; b, the tO a horse's hoof; 

 proboscis extended, of the natural size; c, the same j • 



and is 



opened ; rf, a foot viewed laterally, magnified. 



a very won- 

 derful and beautiful 



