i 
we 
7” 
TEREBRATULA. 5; 389 
and inhabit the present seas; but the existing genera are 
few. 
TEREBRATULA (bored, alluding to the perforated beak). 
Lign. 125.—The common species of this genus must be 
familiar to all who have ever looked into a quarry of Chalk, 
or of Shanklin sand, in the south-east of England. They 
have been humorously called the Fossil Aristocracy, from the 
incalculable antiquity of their lineage. 
The species are very numerous ; more than 300 extinct 
forms have been determined.* Those figured in Lign. 125 
are from the White Chalk, and are beautifully preserved ; 
even vestiges of the colour occasionally remain. In a living 
state, the animal is fixed to foreign bodies by a byssus, or 
peduncle, which passes through the opening in the beak, 
or arched extremity, of the shells.t The most interest- 
ing circumstance relating to these mollusca, is the respi- 
ratory apparatus, which consists of two long ciliated tubes, 
spirally coiled, united at their base, and supported by slender 
calcareous processes, which are often preserved in the fossils. 
Thus, in specimens from the soft chalk, the calcareous earth 
may be removed from the interior of the shell, and the 
appendages exposed, as in the examples, Lign. 126, figs. 1, 2 ; 
and in the shells that are empty, these processes occasionally 
remain distinct, or are coated by a thin pellicle of calcareous 
Spar, or pyrites. 
In the smooth Zerebratule, the laminations of the shell 
are full of minute perforations, which may be seen by a 
lens of moderate power; the appearance of this structure, 
* See Catalogue of Terebratulide, published for the British Mu- 
seum. 
+ In the British Museum (Eastern Zoological Gallery, case table A) 
there are between thirty and forty recent terebratulee (7. australis, 
Quoy, a plaited species, much resembling 7. fimbria of the Inf. Oolite, 
Cheltenham) attached with their byssi to a block of stone, from Port 
Jackson, where it was found by Mr. Jukes just below low-water. 
