108 
fail to be of future use. The case has been indifferently 
figured by Pennant. It is remarkable for its uniformity, 
being perfectly straight, but somewhat conically tubular. 
It is composed of bits of shells and chosen particles of 
sand, so arranged as to form an equal surface; the gluten: 
cementing them together entirely covering the inside, and 
appearing externally between the particles when examined 
by a magnifying glass only. There is little doubt but 
these animals quit their cases, as we have seen- fresh water 
animals with tubular cases do, and dexterously recover 
them again. The case of this animal, which is called 
Salella tubiformis, has with the rest of that genus been 
placed with the Vermes Testacea ; we do not find fault 
with this arrangement, as, perhaps, without the animal, 
there may be no better place for them. 
They are found on the Sandwich and other shores, but 
the cases are oftener found without the animal than with it. 
We have not had the pleasure of seeing this animal in its 
natural situation ; and have therefore placed it as if fallen 
on the shore, with the animal nearly out of the covering ; 
the other animal has fallen carelessly on its back : — thus a 
view is given both of the back and front. The case is 
said to be found immersed perpendicularly in the sand', 
with the broad end and head upwards. 
