OF SOUTHERN INDIA. 
9 
teeth ; lia3mal valve with two shelly hraehial proeesses ; neural valve with the beak 
pointed, iueurved, perforated, or elosed.* 
Of the four generat of this family, Rhynchonella, CamaroyRioria, JPentameriis, 
and probably Dimerella of Zittel, only the first one is represented in the South 
Indian eretaceous deposits. 
RHYNCHONELLA, Fischer, 1809. 
(Sec Davidson, British Foss. Brachiopoda, Vol. I, and Classificat, of Braohiopoda). 
Shell very variable in shape, changing from triangular to elongately ovate or 
round ; surface rarely smooth, usually radiately ribbed or striated ; generally with a 
fold and sinus in front, rarely without them. Neural valve with a pointed, sharp 
beak, having a foramen on the inner side below the point, which is, however, occa- 
sionally so much tiu’ued upwards as to cnth’cly close the perforation; deltidium 
small, partially or entirely surrounding the foramen, and sometimes forming a regular 
tube ; hinge with two diverging cardinal teeth, supported by dental plates, extend- 
ing to the base of the valve below, and enclosing a more or less marked depression 
in which the shell and peduncle muscle is attached, and below it is situated the 
large adductor scar. Haemal valve with two apophysary flattened and grooved 
lamellae, separated at the base and somewhat turned upwards ; below it are the four 
adductor scars, separated by a short more or less developed ridge. 
Species of lihynchonella occur from the oldest sedimentary deposits up to the 
present time. Dali (American Journ. of Conch., vol. v, 1870, p. 151 and seep) 
gives five recent species, psittacea, (xlrctic Seas) ; nigricans, (New Zealand) ; Grayi, 
(Fiji Isl.) ; Woodicardi and lucida, (Japan), to which R. Sc q., has to he 
added. It is very probable that the recent researches in deep sea di-edgiug will 
considerably increase the number of these monuments of ancient animal life. 
I can distinguish from the South Indian cretaceous beds six different species, 
most of which exhibit close affinities to others from the LTpper Greensand and Chalk 
deposits of Europe, but only one of the species appears to be really identical. 
Possibly, when more extensive materials have been collected, the identification of 
some of tlie other forms may be ascertained, which must, at the present moment, 
be considered as new to science. 
1. Revnceonella metua, SloUczka, PI. 1, Figs. 3-1. 
llliyn. testa transverse irregulariter subovata, tuniida ; vulva hccniali altera multo 
convexiore ; umhone parco ; f rente seniipartita timfornie dejlexa ; superficie crasse- 
costatu : costis circiter 16, stih-obtusis, fere (xqiddistantibns, sublmvigatis, prope um- 
boneni obsoletis ; 16 mm. longa, 18 lata, 10'5 crassa. 
? Variatio — vulva neurali siddrigona, costis circiter 12, crassis, acutis, striis 
incrementi lamellatis intersectis, usgue ad apicem extensis ; 20 mm. longa, 22 lata. 
The tj^jical form, represented in fig. 3, is a transversely subovate, tumid shell, 
with the haemal valve much more inflated than the neural one, the latter having 
* It is probably only in aged specimens that the foramen becomes closed. 
t Also Rhynchopora and probably Uanithyris ; compare Dull in Am. J. Conch., 18/ 1-1872, vii, p. 09. 
C 
