8 Messrs. II. B. Newton and G. C. Crick on some 



of fossils from that area of India, now in the British Museum. 

 The late Dr. H. F. Blanford recognized some distorted 

 specimens from the Himalayan Jurassics, previously figured 

 by Herbert and Everest as Modiola and by J. de C. Sowerby 

 as Nucula, as forms of the N. ? cuneiformis, an opinion which 

 was subsequently confirmed by Stoliczka in his memoir 

 dealing with the Spiti Shales of the North-western Himalaya. 



The Arabian shells show distortion through pressure as 

 characterize most of the Spiti examples; their valves are of 

 similar size and ornamentation, just as inflated, possessing in- 

 curved posterior umbones, the surface of posterior end being 

 abruptly truncated and mostly occupied by a w r ide lunule. 

 The characteristic dentition of the genus has been displayed 

 by the rubbing down of the dorsal surface of one of the 

 specimens. 



The Outch specimen used for comparison exhibits rather 

 more roundness of contour, although the slightly angulate 

 appearance of the Arabian valves is probably more or less 

 due to the pressure to which they have been partially subjected 

 during the period of fossilization. 



Accompanying the specimens of Nucula cuneiformis are 

 some very depressed valves which have probably undergone 

 lateral pressure, making it possible that they belong to the 

 same species ; a rubbed down surface of one of these valves 

 exhibits the characteristic nuculoid dentition. 



Among European shells this species is closely related to 

 Nucula ornati of Quenstedt (' Handbuch Petrefactenkunde,' 

 1852, pi. xliv. fig. 7, p. 528) from Kelloways Rock and 

 Oxford Clay horizons, a form subsequently recognized by 

 Albeit Oppel as Nucula concilia of Orbigny ( l Prodrome Pal. 

 Strat.' 1819, vol. i. p. 339; 'Die Juraformation,' 1857, 

 p. 565) of Callovian age. The same form has also beeu 

 figured under the name of N. ornata, Quenstedt, from the 

 Oxford Clay of Weymouth, in Robert Damon's ( Geology of 

 Weymouth,' 1888, pi. ii. figs. 6-8), the types of which are in 

 the British Museum. 



Loc. Near Dihala. 



Gastropoda. 



Genus TEOCHUS, Linnseus. 



Trochus arabiensis, sp. n. (PI. I. figs. 8, 9.) 



Descriptio?i. — Shell conical, smooth, and with subobtuse 

 apex; with five depressed, narrowly sutured, slightly turreted 

 whorls on nearly the same plane, which are more or less 



