812 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXII. 



Ne. XXX.—OPPELI^ TENUILOBATAE (?) IN CUTCH. 



In his work on "The Fauna of the Spiti Shales" (Pal. Ind. Ser. xv., vol. iv.) 

 on page 38, Dr. V. Uhlig remarks " We should gain a clearer insight into 

 this matter if a larger number of Tenuilobata happened to be known from 

 the Katrol group of Cutch. Unfortunately, one species alone has been so 

 far described from that group, namely, Oppelia plico&iscus, Waag." &c. 



In the Katrol beds I have found several specimens or fragments of 

 specimens of Tenuilobata (as I judge them to be) which are not Oppelia 

 plicodiscus. I have placed several in our Museum, and I cannot at the 

 present moment describe them, but I believe that there are more than two 

 species. I have now in front of me a rather worn half specim<3n of one 

 species, whose suture is brilliantly clear and is, I may say, identical with 

 the suture of Oppelia indopicta as given in Fig. iii of Plate III in 

 Uhlig's work. But though the suture seems so exact and the transverse 

 section seems to me the same, the ornamentation somewhat differs. 

 Another specimen with identical suture was recently found by Major R. S. 

 Pottinger, a perfect gem, though it consists of the earlier stages only. 

 This is in the Museum. My specimen too has no extant body chamber. 

 The measurements of the two appear to me to be these. 



Spec. No. 1. No. 2. 

 Diameter. . . . . . . . 37 mm. 78 



Umbil Diam 3 6 (?) blocked. 



Height of whorl . . . . 21 48 



■ Height of whorl from preced- 

 ing periphery.. .. ..11 20 



Maximum breadth . . . . 9 19. 



I will not vouch for absolute accuracy, but the figures are near enough. 

 The widest part is about the middle of the whorl. 



In Indopicta there are 8 broad low costte : in this specimen before me I 

 count 10 on the half whorl only. In Indopicta the costfB die away some- 

 where about the middle of the sides : in mine they run half way down the 

 side, and then kink slightly backwards and die off beyond half way. In 

 horizontal light a sort of faint ridge is seen running above the middle of 

 the whorl through the ends of these ribs. Beyond this ridge is a smooth 

 zone out of which rise imperceptibly numerous faint rounded ribs which 

 climb up to the siphonal edge ; among these numerous intercelary costse, 

 the main ribs reappear again, narrower than before but clearly more 

 prominent than the intercelaries. In horizontal light these seem faintly 

 continuous with the main ribs across the smooth zone, the backward 

 band having righted itself again. 



As I don't profess to be giving a scientific delineation of this species, 

 I will not say more. I hope I have indicated enough to inform any expert 

 who may be interested that Cutch can still provide material which may be 

 useful in helping to clear up some of the many Ammonite problems. The 

 coarse katrol sandstone plays havoc with many of its entombed relics. 

 Some kinds in places are excellently preserved where there is more 

 iron clay — especially Peris^j^hinctes : but Hybonote aspidoceras and Oppelice 

 are not often found in really good condition. 



Of other probable Tenuilobates, one kind is much like the above but the 

 main ribs end oft' in low flat tubercles. Another kind has an extremely- 

 narrow and graceful first Lateral Lobe. Of this the Museum has an admi- 

 rable specimen — the only one I have found. But the former kinds are so 

 not-uncommon that I am surprised that none were provided for Dr. Waa- 

 gen's study. 



Bhuj, 26^ September 1918. J. H. SMITH. 



