282 DR. C. T. TRECHMANN" ON THE [vol. lxxix,. 



Locality. — Lower slopes of Flag Hill, Hokonui Hills; in 

 sandstone. Callovian (?). 



Remarks. — One specimen, rather crushed laterally, consists of 

 a cast, the test missing. Mr. Buckman writes that it has quite a 

 remarkable likeness to RhyncTionella funiculata Deslongchamps 

 of the Callovian. 



Rhynchonella sp. (PI. XVI, figs. 9 & 10.) 



Description. — Outline triangular or subpentagonal, wider 

 than long. Valves fairly well inflated, the dorsal more so than 

 the ventral, beaks small and tapering rapidly. The dorsal valve 

 has a median raised and flattened anterior portion, upon which in 

 one specimen are two, in another four folds, which continue nearly 

 to the beak but become gradually weaker. There are two rounded 

 lateral folds, which continue nearly to the beak. The ventral 

 valve of one specimen has one, another has three median folds 

 which continue to the beak, on each side of which are lateral 

 rounded folds that pass about two-thirds of the way to the beak. 



Dimensions. — Length=15 mm.; width=18 mm. ; thickness 

 = about 9 mm. 



Locality. — Lower slopes of Flag Hill, Hokonui Hills ; in sand- 

 stone. Callovian (?). 



Remarks. — I have two internal casts, both a good deal crushed, 

 which may belong to one species, although one has more and 

 sharper median folds than the other. Mr. Buckman writes that 

 they exhibit the general aspect of Callovian Rhynchonella?, but 

 the internal details (such as they are) differ. The New Zealand 

 specimens show short dental plates doubtfully divergent, and a 

 very short dorsal septum about a quarter of the length of the 

 valve. Dr. F. L. Kitchin * describes a species, JRh. pauciplicata, 

 as having well-developed dental lamellae and a median dorsal 

 septum about a third of the length of the dorsal valve. The 

 specimen (fig. 9), if uncrushed. would resemble in general outline 

 Dr. Kitchin's fig. 4 ; but in the Indian examples the ribs are 

 developed only in the region of the frontal and lateral margins, 

 while in the New Zealand examples they extend nearly to the- 

 beak. 



Rhynchonella sp. (PI. XII, fig. 5.) 



Description. — Shell subtriangular in outline, the sides sloping- 

 straight away from the ventral beak. The latter is slightly in- 

 curved, but the delthyrial region is hidden in the matrix of the 

 specimen. Both valves are about equally inflated. On the ventral 

 valve, which is gently rounded, there is a broad median sulcus 

 which extends about half-way to the beak, and has five low 

 angular folds on it which disappear or merge into the smaller ribs 

 about half-way to the beak. Two angular folds appear on each 



1 ' Jurassic Fauna of Kutch : Brachiopoda ' Pal. Ind. ser. 9, vol. iii, pt. i 

 (1900) p. 70 & pi. xv, figs. 4, 5, 8. 



