Shells of Common Occurrence. 147 
the Helices now disposed of so far as we have got 
‘them in our budget. Our greatest regret is the 
absence of H. pomatia, the largest of the British 
land shells, the favourite shell food of the Romans, 
still eaten in many parts of modern Hurope. 
The Bulimus obscurus, dull or dusky twist shell, 
is considered to derive its first or generic name 
from a Greek term signifying insatiable hunger 
(BovAiwos), and its specific from the Latin, indica- 
tive of its colour (dusky or dull), for scientific 
jargon is generally macaronic, and by no means 
minds a Babel of languages. The shell is not 
large, being generally under half an inch in length 
and a couple of lines in breadth. It is unpolished 
in appearance; and though the animal within bears 
a resemblance to the Helices, or snails, the shell 
without tapers much more considerably, and in 
crawling the creature carries its shelter balanced 
on its back, directed a little to the right, at an 
angle of 50°, or. drags it along the ground, and 
holds it when at rest at an angle of 45°. It is 
found in woods and under mossy trees, on walls and 
under stones. It crawls with speed, as if to justify 
the imputation of being very devouring, and of 
getting rapidly through its fortune. It is by no 
means rare in England. Macgillivray and Duncan 
