II AMITE. 367 
Hamite, 
If we imagine a Baculite to be bent round 
near its centre, until the smaller extremity be- 
came nearly parallel to its larger end, it would 
present the most simple form of that cognate 
genus of chambered shells, which, from their 
frequently assuming this hooked form, have been 
called Hamites. At PI. 44, Fig. 9, 1 1 , represent 
portions of Hamites which have this most simple 
curvature ; other species of this genus have a 
more tortuous form, and are either closely coiled 
up, like the small extremity of a Spirula, (PI. 44, 
Fig. 2,) or disposed in a more open spiral. (PL 
44, Fig. 8.)* y 
It is probable that some of these Hamites 
* Both these forms of Hamite bear the same relation to 
Ammonites that Lituites bear to Nautili ; each bein^ nearly such 
as shells of these genera would respectively present, if partially 
unrolled. See PhHlips' Geol. Yorkshire, PI. 1, Figs. 22, 29, 30. 
Baculites and Hamites have two characters which connect 
them with Ammonites ; first, the position of the Siphuncle, on 
the back, or outer margin of the shell, (PI. 44, Figs. 5^, c. 8*, 
a. 10. 11, a. 12, a. 13, a.); secondly, the foliated character of 
the margin of the transverse plates, at their junction with the 
external shell. (PI. 44, Fig. 5, 8, 12, 13.) The external shell 
of Hamites is also fortified by transverse folds or ribs, increasing 
the strength both of the outer chambers and of the air chambers, 
upon the same principles that we have pointed out in the case of 
Ammonites. (See PL 44, Fig. 8, 9, 11, 12, 13.) 
In certain species of Hamites, as in certain Ammonites, the 
marginal Siphuncle has a keel-shaped pipe raised over it. Others 
have a series of spines on each side of the back. (PI. 44^ 
Fig. 9, 10.) 
