22 Messrs. R. B. Newton and G. C. Crick on some 



whilst in a specimen figured also by de Loriol * from the 

 Upper Kauracian of the Bernese Jura the groove extends over 

 about one-lialf the length of the guard. Further, there are 

 differences in the amount of tapering of the anterior part of 

 the guard, none of the examples mentioned above tapering 

 so rapidly as Etallon's type-specimen. Belemmtes astartinus 

 does not appear to have usually attained such a large size as 

 the Arabian fossil, the only figured example of that species 

 at all comparable with the present specimen being that figured 

 by de Loriol from the zone of Ammonites tenuilohatus at 

 Oberbuchsitten (Soleure), but that tapers anteriorly more 

 lapidly and has a considerably shorter groove. 



It is neither so fusiform, so depressed, nor so widely grooved 

 as the example figured by Quenstedt (' Die Cephalopoden/ 

 1849, pi. xxix. figs. 14a-c) as Belemnites hasfatus dep7'essus 

 ( = Belem7iites calloviensis , Oppel f). Compared with the 

 form figured as Belemmtes siibha status by Waagen from the 

 Jurassic rocks of Cutch, in which species Waagen includes 

 the Cutch specimen figured by J. de C. Sowerby | as Belem- 

 nites canalicidatus ?, and afterwards renamed by d'Orbigny § 

 Belemnites grantanus, the Arabian specimen appears to be 

 part of a more elongated guard a)id to have possessed a 

 much narrower ventral groove. Waagen ji records Belem- 

 nites suhhastatus as being not very commoi in the Cutch 

 Jura, where it is apparently restricted to the beds with 

 Macrocephalites macrocephalus. 



The Arabian specimen is more depressed, more hastate, and 

 provided with a narrower ventral groove than Waagen's 

 Belemnites kuntkoiensis^, which, according to that author, 

 ranges in Cutch through the Katrol and (Jomia groups, or, 

 in other words, from the Upper Oxford to about Lower 

 Tithonian beds ; whilst it appears to have been more elon- 

 gated and more depressed than that author's Belemnites 

 katrolensis*'^, a species which in Cutch is characteristic of the 



* P. de Loriol, Etude sur lea mollusques du rauracien aupMeur dii 

 Jura Bernois, Suppl. 1, 1895 (Mem. Soc. Pal. Suisse, vol. xxii.), p. 5, 

 pi. i. fig. 1. 



t A. Oppel, ' Die Juraformation,' 1856-8, p. 64G (1857). See also W. 

 Waagen, .Jurassic Fauna of Ivutch (Pal. Indica), vol. i. The Oephalc- 

 poda, pt. 1, 1873, p. 14, pi. ii. figs. 4«-rf. 



t J. de C. Sowerby, Trans. Geol. Soc. [2] vol. v. pt. 2, 1840, pi. x.\iii. 

 fig. 2 & expl. 



§ A. d'Orbigny, Prod, de Pal(?ont. 1850, vol. i. p. 326. 



II W. AVaagen, Jurassic Fauna of Kutch (Pal. Indica), vol. i. The 

 Cephalopoda, pt. 1, 1873, p. 15. 



11 W. Waagen, ibid. pt. 1, 1873, p. 3, pi. i. figs. 3 a-f. 

 «* W. Waagen, ibid. pt. 1, 1873, p. 7, pi. ii. figs. 7, 8, 9. 



