344 
ANALYTICAL INDEX. 
CHAPTER YV.—continued. 
§ 
mn 
§ 
II1,—SPIO— 
§ 
ur 
1. 
Swim by violent contortions, : : PAGE 156 
Plate XX. explained, ib. 
11. Nerets contorta,—The Spiral Nereis, ib. 
Length, &e., ib. 
Lies in a close coil, ib. 
Regeneration, 157 
Plate XX. explained, ib. 
12. Nereis MonocERos,—The Unicorn Nereis, ib. 
Length, breadth, &e., ib. 
Constructs a slight tube on the side of its vessel ib. 
Plate XXII. explained, ib. 
13, NerReEIS PUNCTATA (VILLOSA), 158 
Length, organs, colour, &e., ib. 
Swims by horizontal undulations, ib. 
Forms a slight silken sheath, ib. 
Plate X XI. explained, ib. 
This is a genus but imperfectly known, 159 
SPIO SETICORNIS, ib. 
Length, &c., 6 ib. 
Constructs a tube of shelly faemiente ib. 
Lies constantly within its dwelling, ib. 
Account of specimen, ib. 
Plate XX. explained, ib, 
. SPIO CELATA, ib. 
This animal does not ceeced a line i in eee 160 
Description, ib. 
Plate XX. explained, ib. 
Closing remarks on the Nereis, ib. 
MM. Andouin, Milne Sie Delle Ghise M. de Bese 
Savigny, . ° ib. 
Arrangement of the Bente in deta embarrassing: 161 
Finest illustrations of the luminous properties in the Nereis 
ib. 
noctiluca, 
