INTRODUCTION. 



The oldest formation seen in the sections of the Mari hills of Baluchistdn is re- 

 presented, according to Messrs. Griesbach and Oldham, by a massive limestone 

 which is generally devoid of fossils, or at most contains some ill-preserved fossils 

 here and there ; commonest are Brachiopods belonging to the genera Rhynchonella 

 and Terehratvila. 



It is clear that these two genera would not have been sufficient to determine 

 the age of the " massive limestone " with certainty, but fortunately Lala Kishen Sing 

 of the Geological Survey discovered a rich fauna of ammonites in these deposits 

 near Mazdr Drik. It is, however, to be regretted that almost every specimen has 

 suffered more or less from deformation by pressure, and that the finer structure 

 of the sutural line has been completely destroyed in every case. Under these cir- 

 cumstances the specific determination would have been exceedingly difficult 

 had I not been able to compare this collection with the type specimens from 

 the Jurassic beds of Kutch, which have been so diligently worked out by Pro- 

 fessor Waagen. The only fault which I have to find with this fine publication 

 consists in the fact, that the figures of the specimens described do not always 

 represent the original in its actual state, but that they are in many cases consider- 

 ably, and not always happily, restored. The determination from the figures only, 

 as given in Professor Waagen's publication, is therefore extremely difficult, and it 

 may be noticed that my figures differ considerably from those of the species of the 

 same name as shown by Professor Waagen. I have, however, conviitced myself 

 by actual comparison with the Kutch originals that the specimens here described 

 under specific determinations attributed by Prof ess.or Waagen to forms from Kutch, 

 are really identical with these species, notwithstanding the apparent difference of 

 the figures. In two cases, however, I felt under an obligation to reproduce two 

 of Professor Waagen's originals, in order to prove to the reader the identity of the 

 Baluchistdn forms with those from Kutch, as the published figure of the Kutch 

 species differs considerably from the type specimen. The Jurassic limestone of 

 Mazar Drik has up to the present yielded 22 species, of which 17 have been deter- 

 mined specifically, while of 5 only the genus could be determined. Out of the 17 

 species specifically determined, 16 could be identified with species already described, 

 while one form, Perisphmctes baluchistanensis, could be recognized as new. 



The 22 species mentioned represent the following classes : — 



Braehiopoia 2 species (two epecifiially deteruiined). 



Pelecfffioda, 3 „ (none „ ,, ). 



Gastropoda 1 „ (none „ „ ). 



Cephalopoda 16 „ (15 „ „ ). 



