ANALYTICAL INDEX. 
CHAPTER VIII.—continued. 
¥, TEREBELLA PECTEN, PAGE 208 
Description, ib. 
Only one specimen Beauteed: ib. 
Plate XVI. explained, ib. 
. TEREBELLA OSTREZ, 209 
The generic name Terebella iieanplieds ib. 
The Ostrea capable of entering a hard substance, ib. 
Found in the exterior of oyster shells, ib. 
Bears considerable aici to the Terebella, ib. 
Description, ib. 
Organization modified by age, ib. 
Its habitation, a cavity adapted for its tear is lined orth silk, 210 
Twelve have been found on a single shell, ib. 
Plate X XVI. explained, ib. 
Concluding remarks, ib. 
A brilliant phosphorescence belongs to some of ae ear ib. 
Several facts merit particular investigation, ib. 
The generic character, 211 
CHAPTER [X.—AMPHITRITE AND CONGENERA, 212 
Farther illustrations of instinct, ib. 
§ 1, AMpPHITRITE VENTILABRUM,—TZhe Fan Amphitrite, ib. 
Found fixed to a solid foundation fifty or sixty feet below the sea, ib. 
Description, ib. 
Unfolds a splendid sam of many fathers 213 
The animal decked with various colours, 214 
Organic structure dependent on dimensions, 215 
Account of specimens, ib. 
The Pennatula mirabilis, ib. 
The ventilabrum still more sAiiicabiles ib. 
Has the control of 50,000 living parts, 216 
What the precise spirit which actuates them ? ib. 
Its architectural operations described, : 217 
Nothing so admirable as the operation of so many Renee organs, 218 
Unlike the Terebell, if once dislodged, the Amphitrite remains 
unprotected, : ib. 
Account of specimens, 219 
Tube composed of earth and alnien, ib. 
Perhaps necessity urges the constant preleapatien of the dyelinet 220 
