230 GINGLYMACONCHA. PHOLADID. 
aspect of the animal: of the latter, we possess no indigenous 
example. 
The presence of these supplementary pieces, or as they are 
termed, accessory valves, has caused this family to be excluded 
from what in common language are denominated divalves, and 
to be arranged along with Chitonide, a family of the class 
Gasteropoda, and associated with the class Cirripedes or Bar- 
nacles, which has not even the slightest connection with the 
molluscous type. This almost incredible confusion presents to 
our view but one of those innumerable inconsistencies, com- 
mitted by Linnzeus, and of which the most zealous admirers will 
hardly acquit the immortal author of the misnamed Systema 
Naturee. 
The Pholadidee inhabit the sea, and reside in perforations 
which they make, by a power by no means understood, in cal- 
careous rocks, slate, hard clay, or wood. These hollows have 
only a small opening for the exit of their respiratory tubes. 
All the species are phosphorescent, and their shells invariably 
of a white colour. 
Stirpium et Generum Synopsis. 
Stirps 1. Testa anticé infra laté emarginata. 
* Testa parte emarginatd apertd. 
Testee accessorize 4: 2 umbonice: 1 post- 
winbonica: °1 dorsalis.) °2"< 22 Soe! 1. PHouas. 
Testa accessoria 1: postumbonica, bifida, 
PaEva. OSE A as Se ee eee 
Testa accessoria 1: postumbonica, longis- 
sima umbones tegens .............. 3. ANCHOMASA. 
** Testa parte emarginatd nonnunguam clausd. 
Testee accessorize 2: umbonicee inzequales, 
parce angulum delinientes . ........ 4. Capmusta. 
Stirps 2. Testa anticé integra. 
Testa accessoria 1: postumbonica, anticé 
producta, umbones tegens .......... 5. BARnNia. 
