344 ANALYTICAL INDEX. 



CHAPTER V. continued. 



Swim by violent contortions, . . . PAGE 156 



Plate XX. explained, . ib. 



11. NEREIS CONTOBTA, The Spiral Nereis, . ib. 



Length, &c., . ib. 



Lies in a close coil, . . ib. 



Regeneration, . . 157 



Plate XX. explained, . . . . ib. 

 * 



12. NEBEIS MONOCEROS, The Unicorn Nereis, . ib. 



Length, breadth, &c., . . . ib. 



Constructs a slight tube on the side of its vessel, . ib. 



Plate XXII. explained, . . . ib. 



13. NEREIS PUNCTATA (VILLOSA), . . . 158 



Length, organs, colour, &c>, . ib. 



Swims by horizontal undulations, . . ib. 



Forms a slight silken sheath, . . . ib. 



Plate XXI. explained, .... ib. 



II. SPIO 



This is a genus but imperfectly known, 159 



1. SPIO SETICORNIS, . . . . ib. 



Length, &c., . . ib. 



Constructs a tube of shelly fragments, . . ib. 



Lies constantly within its dwelling, . . ib. 



Account of specimen, . . ib. 



Plate XX. explained, ib. 



2. SPIO CELATA, ...... ib. 



This animal does not exceed a line in length, . 160 



Description, . . ib. 



Plate XX. explained, .... ib. 



Closing remarks on the Nereis, . . ib. 



MM. Andouin, Milne Edwards, Delle Chiaie, M. de Bosc, 



Savigny, ...... ib. 



Arrangement of the genus in detail embarrassing, . 161 

 Finest illustrations of the luminous properties in the Nereis 



noctiluca, ..... ib. 



