C 29 ] 
AMMONIA. 
Univalves, whofe injide are divided into many 
regular and nearly equidijfant cells or chambers, the 
partitions of which are not romdijh and with an even 
edge, as thofe of the Orthoceros and Nautilus ; hut are 
JlaJhed, or jagged, into procejfes or appendages, 
which laid together tally and clofe into one another 
Jo Jrongly and curioujy, that, when joined, the fats 
or furface of the whole Cornua dmmonis* are embeU 
lifted with a beautiful leaved work, exa^ly fimilar to 
that on the Jkulls of animals: and this by foffilogijs i$ 
called ihefoliaceous futures of the Ammonites^ The cells 
have a pipe or fiphunculus, that opens into, a\id com^ 
vmnicatesfrom chamber to chamber. 
The Jpires are cylindric, and comeHed to each 
other: they gradually diminifi or taper (on both levels 
equally alike) from the circumference to the center ; fo 
that by the gradual tapering of the fpires to the ccn,ter^ 
(he centers of both flats are concave fC 
n With 
* The name originates from their refcmblance to the 
ram’s horns wherewith the antients reprefent Jupiter 
Ammon : whofe celebrated temple was fituated in the 
burning fands of Libya, 
i Da Cofta’s elements of conchology, p. 154, &c« 
