G 
CEETACEOUS BEACniOPOEA 
muscles of the Pelecyiwds, the divaricators replace the inner ligament or cartilage, 
and the adjnstators arc sirai)ly a modilication of the pedal muscles, and the 
peduncle itself is, strictly speaking, only a modifted foot turned backwards; all 
these organs have quite similar structure and functions in the two classes. The 
nervous ring at the oesophagus is similarly placed in both classes, and the ali- 
mentary canal terminates similarly behind the posterior part of the adductor, 
Tlie enormous development of the mantle lobes as compared with the small 
size of the body may appear abnormal in the Brachiopoda, hut we find it of exactly 
similar proportions, for instance, in Ilodiola, Finna, Flacuna, and several other 
Pelecypods. 
I hav'C very little doubt that when the anatomy of the Anomiidee and many 
Brachiopoda are better studied, they will show still more points of resemblance than 
are generally known at present. 
The Brachiopods have been divided into two large groups, the pleubofygia and 
the APTOiA. The former have the valves not joined to each other by any kind of 
hinge-teeth or folded margin; they have no internal solid brachial apparatus, and the 
alimentary canal terminates laterally Avith an anus. The latter have the valve 
joined by a simple straight slightly thickened margin, or by distinctly dcAnlopcd 
hinge-teeth and corresponding sockets ; the shelly brachial apparatus is rudiiuentary 
or Avell dcA'elopcd, and the alimentary canal is believed to terminate blindly. The 
former group includes the families Linoulidji, Discinid^, and Cranpidje, and the 
latter the Pi 20 Z ) r 7 cr / z ).«', Cjiosetid.p, Steophompnipm, Spiripepivas, EsrNCiWNELziDJ^ 
and Teresratulid^. Erom the last the Tiieciidae have probably to be separated 
as a distinct family, and somcAAliat dilferent arrangements have also been proposed 
regarding some of the paheozoic forms. 
Of the eight families noticed, there are only three represented in the South 
Indian cretaceous deposits. 
Fennihj— CBANTIDJE* 
The animals of the single known genus Crania j)Ossess fleshy, spirally coiled 
arms, winch arc attached to the sides of a small sub-central process in the hocmal or 
dorsal (= upper) valA'c. 
The shell consists of two sub-equal or unequal calcareous A'ah’es, of a minutely 
tubidar structure, fixed to each other by tAvo pairs of adductor muscles, but Avithout 
any special hinge-teeth, or any solid brachial system in the lucmal A'ah'e. 
Genus. — Crakia, Relzius, 1781 . 
Davidson, Brit. Boss. Bracliiopoda, vol. I, p. ]22. 
„ Class, cler Bi-achiopodon, transl. by Suess, 1850, p. 137. 
Shell sub-orhicular, or subquadrate, inequivalve, with the nemal valve free or 
usually adherent, or attached to sub-marine objects with a larger or smaller portion of 
* A revision of tbe genera of the family is given by Dali in Am. Jour. Coneb., vol. vii, p. 71, and the synonymy 
of tbe recent species is noted. 
