CEPHALOPODA. 



entirely at the will of the animal. The receptacle of the ink i* seat- 

 ed in the liver ; the glands of the oviducta are small. Some of them 



POLYPUS, Aristotle. 

 Have two alternate rows of cups along each foot. 



The common species, Sepia octopodia, Lin., with a slightly 



Genus Renulina . 



CristelJaria. 



. . . Orbiculimi . 



Miliola ., 

 Gyrogona 

 Melouia . 



Rotalia . . . 

 Lenticulina. 

 Placentula . 



Discorbis . . 

 Siderolites . . 

 Polystomella 

 Vorticialis .. 

 Nummulites 

 Nautilus 



Third Family. Les Cristac&s. 



Fourth Family. Les Spherules 



| Fifth Family. Les Radicles . . > 



Sixth Family. Les Nautilac&s 



Shell semidiscoid;mul- 

 tilocular, with sim- 

 ple septa ; the spire 

 eccentric. 



"Shell globose, niultilo- 

 cular, with simple 

 septa, spheroidal or 

 oval ; the whorls of 

 the spire enveloping, 

 or the chambers uni- 

 ted in a tunic. 

 Shell discoid, multilo- 

 cular with simple 

 septa, spire central, 

 chambers lengthened 

 and discoid, extend- 

 ingjfrom the centre to 

 the circumference. 



f Shell discoid, spire cen- 

 trical, cells short, 

 and in a spiral line 

 not extending from 

 the centre to the cir- 

 cumference. The 

 greater number are 

 fossil species. The 

 septa, as in the pre- 

 ceding genera, sim- 

 ple, neither notched 

 nor undulated on the 

 internal partition of 

 the testaceous exte- 

 rior. 



i 



Ammonites. "1 



Orbulites I 



Ammonoceras. . f Seventh Family. Les Ammondes < 

 Torrilites .... I 

 Buculites .... J 



" Shell multilocular ; sep- 

 ta sinuous, lobed, 

 and cut in their con- 

 tour, uniting toge- 

 ther against the in- 

 ternal partition of 

 the shell, and arti- 

 culated in sinuous 

 sutures divided and 

 dentated. Most of 

 these are known only 

 in a fossil state. 



Second Division. C^phalopode3-monothaJame$.^ Navigators. 



f Shell unilocular, alto- 



