191 
formation, Sag. Hauerinum, Kon., Sag. Orbignyanum, Vern., 
Sag. primas, Waaa., the others are found in the Triassic rocks, 
Sag. Gabbi, Moss., Sag. Haidengerit, Hav., Sag. Walteri, Moss., 
Sag. Zigmondyi, Moss. 
Genus Amauruevs, Montfort.—Siphonal side of the shell 
sharpened or keeled; ribs, when present, flexed forward, and 
ending in a scaly (fig. 87) or articulated ridge or keel (fig. 38) ; 
the external shelly lamina in some species developes fine spiral 
Fic. 36.—Amaltheus margaritatus, Mont. Fia. 37.—Amaltheus cordatus, Sow. 
lines; body-chamber short; one half to two thirds of a whorl. 
Mouth-border simple, ventral portion ending in a long projecting 
process. lLobe-line extremely ramified, the siphonal lobe 
shorter than the principal lateral lobe, which is mostly broad 
‘and wedge-shaped. <A divided horny Anaptychus has been found 
in this genus. 
The genus Amaltheus has an extensive geological range ; it is 
found in the Trias, Amal. megalodiscus, Beyr., Amal. floridus, 
Wulf; it is largely developed in the Jurassic strata, commencing 
with Amal. Guibalianus, v’OrB., Amal. margaritatus, Brug. 
(fig. 38,) and Amal. spinatus, in the Lias, and many forms are 
found in the higher Oolitic beds, as Amal. cordatus, Sow., Coral 
Rag (fig. 37); numerous species are likewise discovered in the 
Cretaceous rocks, as Amal. Gevrilianus, p’Ors., Amal. Vibraye- 
anus, D’ORB. 
Genus Scutomnpacnta, Newm.—Shell keeled, with strong 
forward bent ribs on the sides, sometimes developing lateral 
