SERPULA. CREEPER . 
149 
Iar, a little curved at the .smaller end and obliquely rounded 
at the other, the pointed end colored with a mixture of 
changeable purple blue or green : from the broad to the 
i pointed end run about eleven ribs, commencing on the car¬ 
tilage side and extending over about two-thirds of the sur¬ 
face, leaving the other part marked only by curved striae in 
an opposite direction ; inside smooth, perlaceous : length 
three inches ; breadth six or more. 
Variety A. Smooth and without 3pines. 
Variety B. Furnished with concave spines, especially 
along the ribs, which increase in size as they approach the 
larger end. 
( On the western coasts. «. v. 
3. Pinna muricata. Prickly Nacre . 
Montagu, pi. 5. f. 3, 
Shell thin, brittle, semitransparent, flesh-color but darker 
at thepointed end which is quite straight, obliquely rounded 
at the broader end, with ten or twelve broad ribs running 
from the larger to the pointed end covering the whole sur¬ 
face of the shell, and marked with a few intermediate 
smaller ones at the pointed end; these ribs are furnished 
with a few concave spines, chiefly towards the broader end \ 
length about two inches ; breadth live or more. 
On the Dorsetshire coast: rare. v. m. 
SERPULA. CREEPER , 
Shell with a single valve, tubular, variously 
shaped, sometimes divided by imperforated inter¬ 
nal ‘divisions at unequal distances. 
A. Attacked , and spirally twisted , 1 to 9. 
B. Attached , and irregularly twisted, 10 to 15. 
€. Detachedand curved or twisted. 16 to 20. 
D. Detached, and botile-shaped, 21 to 29. 
A. Attached, and spirally twisted, 1 to 9. 
1. Serpula spirorbis. Spiral Creeper. 
Lister, pL 553. f. 5 — Pennant, pi. 94. f. 1— Da Costa , 
o 3 pi. 2. 
