The Invertebrate Fauna of the UitcnJiaye Scries. 93 



In India, T. ventricosa occurs numerously at various localities in 

 the marine beds of the Oomia Group in Cutch, notably in the 

 neighbourhood of Oomia and Goonaree ; it is also stated to have 

 been found by King in an outlier of the Tripetty beds at Inna- 

 parazpolliam, to the north-west of Coconada on the south-eastern 

 side of the Indian peninsula " ; It is recorded, too, from the 

 Margalla Pass in the district of Hazara, where it is said to occur in 

 abundance.! 



Remarks. Trigonia ventricosa bears a general resemblance to 

 members of the aliformis group of the section Scabrae, particularly 

 to T. aliformis Park.,{ with which it was confounded by von Buch, 

 and to T. scabricola Lycett ; but the relative shortness and great 

 height of the outline, the very strong anterior inflation, and the 

 coarse and salient character of the ornaments on the anterior part 

 of the adult shell, serve to separate it from all known members of 

 the section in Europe. It has been repeatedly pointed out that 

 much closer agreement is shown to T. tuberculifera Stoliczka, from 

 a higher horizon in the Cretaceous rocks of Southern India. The 

 resemblance appears to be remarkably great, but unfortunately 

 Stoliczka's description and figures of T. tuberculifera leave some- 

 thing to be desired. I have elsewhere drawn attention to the fact 

 that in the figure of the front view of Stoliczka's type |] the ribs of 

 the right and left valve are represented as though placed opposite to 

 one another at their frontal terminations ; in T. ventricosa, on the 

 other hand, as in other members of the section, these ribs alternate 

 in position, and it seems probable that an error was committed in the 

 execution of this figure of T. tuberculifera. 



A comparison of T. ventricosa with T. kraussi sp. nov. will be 

 found in the remarks appended to the description of the latter. 



T. sub ventricosa Stanton, from the Belgrano beds of the 

 Pueyrrydon Series in Patagonia,*^ so far as can be gathered from 

 the description and figures of that shell, is of very similar type, but 

 seems to be less strongly inflated, and to be of relatively more 

 elongated form. 



T. delafossei Bayle and Goquand,** from the Neocomian of Chili, 

 also shows a general agreement with T. ventricosa, and may 



* King (1), p. 229 ; Feistmantel (2), p. 164 ; Feistmantel (3), p. xxxvii. 



f Wynne (2), p. 125 ; Medlicott and Blanford (1), p. 503. 



I Parkinson (1), p. 176, pi. xii., fig. 9; Lycett (3), p. 116, pi. xxv., figs. 3-0 

 (1875). Lycett (3), p. 130, pi. xxvii., figs. 4, 5. 



|| Stoliczka (2), pi. xv., fig. 10 (1871). I Stanton (3), p. 18, pi. iv., figs. 19, 20 



** Bayle and Coquand (1), p. 37, pi. viii., fig. 27; E. A. Philippi (1), p. 85, 

 pi. xxxvi., fig. 4 ; Paulcke (1), p. 296, Taf. xvii., fig. 9. 



