532 



MOLLI/SCA 



HUB-KINGDOM VI 



narrowed and transversely elongated, but always has an entire outline. Siphuncle 

 generally large, nummuloidal, and often has actiniform 

 lamellae and endosiphundes in later stages. Shells mostly 

 endoyastric. 



Codoceras, gen. nov. Excessively short and rapidly 

 expanding cyrtoceracoiies like some species of Rizoceras, 

 but with large living chambers, narrow venter, and large 

 siph uncle just ventrad of centre. Aperture constantly open. 

 Type 0. (Gyrt.} indomitum, Barr. sp. Silurian. 



Protophragmoceras, gen. nov. (Fig. 1086). Similar to 

 the last, but form more compressed, and siphuncle near the 

 venter (internal). Differs from Phragmoceras in having 

 aperture open throughout life. Type P. (Cyrt.) Murchisoni, 

 Barr. sp. Silurian. 



Gomphoceras, Sowb. Stout short orthoceracones and 

 cyrtoceracones similar to some species of Phragmoceras, but 

 straighter, stouter, and less compressed in form, and geroiitic 



aperture less contracted laterally. Hyponomic sinus shorter, 



T , r\ f i n-i 



a curvature exogastric. Ordoviciaii and Silurian. 



Phragmoceras, Sowb. (Figs. 1087, 1088). Compressed' 

 endogastric cyrtoceracones and gyroceracones, oval in section, and venter narrowly 



FIG. 1086. 



Protophragmoceras Murchisoni, 

 Ban. sp. Silurian (E); Loch- 

 kow, Bohemia. 1/2- ' 



FIG. 1087. 



Phragmoceras Broderipi, Barr. Silurian (Etage E) ; Lockhow, Bohemia. 

 !/2 (after Barrande). 



Phragmoceras Loveni, 

 Barr. Silurian (E) ; Loch- 

 kow, Bohemia. Section 

 showing lamellar organic 

 deposits (after Barrande). 



rounded. Siphuncle large and near the venter (internal). Gerontic aperture much 

 contracted laterally, the hyponomic area very long and narrow. Silurian. 



Incertae Sedis. 



Nothoceras, Barr. Represented by the single species N. bohemicum, Barrande, in 

 which the septum turns orad, forming an inverted funnel. This funnel connects with 



I 



