The Hijlory (/ANIMALS, 185 
a great way : the whole furface of the fhell is fmooth, and it's fubftahce extreamly 
thin ; it’s colour is a dufky brown on the outfide, and a paler whitifh brown within. 
We meet with it in the fen-ditches in Lincolnfhire in vafl abundance, and fome- 
times in the muddy waters about London. 
Dolium fuhovatum ore longiore et anguftiore. 
'The oval Dolium , with a longer and narrower mouth . 
This is near an inch in length, and two thirds of an inchin diameter j it’s fubftaiice 
is extreamly thin, and it’s colour a dufky brown: the body approaches to an oval fi¬ 
gure, but it is fomewhat bent in toward the extremity : the clavicle is very fhort and 
inconfiderable 5 the mouth is large, but lefs fo than in the former fpecies; it is indeed 
as long as in that, but the lip is not expanded in that manner, fo that it is much nar¬ 
rower, and approaches to an oval figure 
We have this in fome of the ditches about London in very great abundance, 
Dolium fuhrotundum flavefcem ore ovalo. 
The yellow , round Dolium , with an oval mouth . 
This is about half an inch in length, and as much in diameter; the fubftance of 
the fhell is extreamly thin and delicate, and it’s colour a pale yellow : the body is of 
a roundifh figure, and the mouth is large and oval; the clavicle is very final!. 
We have this in the ponds in Northamptonfhire very common ; I have alfo, fome 
years, feen many of them in the ditches in Tothil-fields. 
Dolium fubovatum albidum ore amplo . 
The white y oval Doliutn y with a large mouth . 
This is about three quarters of an inch long, and half an inch diameter: the body 
is of a form approaching to oval, but indented toward the verge of the mouth 5 the 
clavicle is very inconfiderable, but it is fharply pointed at the extremity: the mouth is 
large and roundifh, but with fome approach to the oval: the colour of the whole fhell 
is a beautiful white. 
It is frequent in fome of our fhallow rivers, where there are many weeds. 
The other fpecies of frefh-water Delia are, 1. The fhort, round-mouthed, olive- 
coloured Dolium. 2. The oval, yellowifh, thicker Dolium, with a very frnall cla¬ 
vicle. 3. The oblong, wide-mouthed, reddifh Dolium, with a fomewhat longer cla¬ 
vicle. 4. The fhort and depreffed, oval-mouthed Dolium. 5. The very finall, 
blackifh Dolium. 
AMMONITE, CORNU AMMONIS SHELLS. 
f | ^ HOUGH we have not, among the almofi; infinite variety of the Sea-fhells, 
jj_ any one of the figure and ftru&ure of the foffile Cornu Ammonis, we have 
feveral fmall fhells of the frefh-water kind, which in all refpedts agree with them 
efpecially with the more common kinds. ^ 
Ammonia variegata ore majore. 
The larger-mouthed\ variegated Ammonia . 
This is one of the moil elegant among the whole feries of frefh-water fheils: it is 
of a rounded, depreffed figure 5 it’s diameter is about an inch, and it’s thicknefs to¬ 
ward the mouth a third of an inch : it confifis of about four volutions, the part near- 
eft the mouth being largeft, and the body growing gradually fmaller, all the way of 
the fpiral, afterwards to the center, where it forms a little umbo or button : the mouth 
is fomewhat larger than a plain fegment of the fhell would form, there being a little 
elevated lip all round it: the furface is obfeurely undulated in a tranfverfe direction • 
the colour is a pale grey, variegated with brown, in very irregular fpots and lines: 
when the fhell is broke, it’s cavity is found to be not fimple and uniform, but divided 
into a number of cells, in the manner of that of the Nautili, and of the foffile Cor- 
Bb b 
nua 
