MOLLUSCA — CEPHALOPODA. 



169 



The Oolitic series includes Macroceplialitcs from India, and Gallery- 

 various genera from the Bajocian rocks of Calvados and the t^^^q^^^^q 

 corresponding Inferior Oolite of this country. A specimen s! 

 referred to Stepheoceras Brodiaei has a furroAv down one side 

 of the last whorl, the result apparently of injury to the 

 secreting surface. Cadomoceras [0 choir aitstes] cadomense is 

 eccentrically coiled, and has projecting ears at the sides of 

 the shell-aperture. Ha'plopleuroccras suhsimiatum is remark- 

 able as repeating the general form of Paltopleuroceras spinatum 

 in the Middle Lias ; this is one of those similarities of form 

 in different genera that has led to so much confusion in 

 classification. Here we may note a fine aptychus from the 

 Stones field Slate, and a beautiful Stepheoceras from the 

 Great Oolite of Mincliinhampton. The ensuing Cornbrash 

 furnishes good specimens of Macrocephcditcs. The larger Wall-ease 

 ammonites from the Lower Oolites include fine examples of 10- 

 species giving their name to well-known horizons, such as 

 the type-specimens of L^ld^vigm Murcliisoncte and Stepheoceras 

 IIumphriesiamir}i, also Parkinsoiiia garantianct, Strigoceras 

 Truellei, Goeloceras [Stephanoceras] Blctgdeni (Fig. 95 d), 

 and Parkinsonia Parkinsoni. There are some very large 

 specimens of Parkinsonia dorsetcnsis and others, in section, 

 or polished to show the sutures. The type-specimen 

 of Fontannesia Boioeri from the Inferior Oolite of Bradford 

 Abbas preserves its long ears, and here is also the type- 

 specimen of " Ammonites " Tessonianus, d'Orbigny, from the 

 Tesson collection. Among Oxfordian species the well-known 

 Cardioceras cor datum repeats the general form of Amaltheus Wall-ease 

 margaritatus, although derived from quite a different stock. 9. 

 Very fine series of this genus and of Cadoccras are in the 

 Wall-case. The Callovian series furnishes several charac- Table-ease 

 teristic genera, among them the highly ornamented Gosmoceras. ^• 

 Many Oxfordian species of this genus have very long 

 processes or ears from the sides of the aperture. From the 

 Oxford Clay of Wiltshire come large specimens of these as Wall-ease 

 well as of Proplanidites Kocnigi with a smooth senile stage. ^* 



The Coral Eag of England is noted for the internal casts Table-ease 

 of the chambers of ammonites, from which the shell has been ^• 

 dissolved away. These belong mostly to Aspidoceras ^aU-case 

 perctrmatitm, of which some specimens from Brora, in 

 Sutherland, are also shown. ITumerous aptychi are found 

 in the Kimmeridge Clay, especially at Ely, and the same 

 forms occur in connection with their ammonites in the 

 contemporaneous Solenhofen Stone. Near these are specimens 



