THE CAMBEIDGE GAULT AND GPvEENSAND. 285 



with a slight sigmoidal curve from back to front, closely agreeing 

 with the description and figures of the above authors*. 



The fish-remains of the Cambridge bed have been much neglected, 

 and many more species remain to be identified. Otodus appendieu- 

 latus has been made to include several forms of teeth, some of which 

 not improbably belong to other species. 



I am glad to say that Mr. T. W. Bridge, of Trinity College, and 

 Demonstrator in the Museum of Comparative Anatomy, is investi- 

 gating these fish-remains • and we may therefore hope soon to pos- 

 sess more knowledge about them, and to chronicle some fresh forms 

 in our lists. 



Cephalopoda. 



Nautilus albensis, D'Orb. 



Nautilus albensis, D'Orb. Prodrome, ii. p. 122 ; Pict. & Campiche, 

 Ste.-Croix, i. p. 134, pi. xvii. 



This shell, which is not uncommon in the Cambridge bed, has 

 been named If. radiatus by Mr. Seeley. According to the observa- 

 tions of MM. Pictet and Campiche, pp. 117 et seq., several species 

 appear to have been confounded under this name, especially If. neo- 

 comiensis, D'Orb., and If. Neckerianus, Pictet. They limit the If. 

 radiatus of Sowerby to a Chalk-marl species with a large umbilicus, 

 and describe a fourth form from the Gault under the name of JSf. 

 albensis, D'Orb., with which our Cambridge specimens closely agree ; 

 this is characterized by a very small umbilicus, and the position of 

 the siphon near the internal edge of the chambers. I am not, how- 

 ever, fully persuaded of its specific distinctness from If. Neckerianus. 



Belemnites ultimus, D'Orb. 



Belemnites ultimus, D'Orb. Pal. Pr. Sup. p. 24 ; Sharpe, Cret. Moll, 

 pi. i. f. 17. 



B. minimus (pars), Pict. & Camp. Ste.-Croix, i. p. 103, pi. xiii. f. 1. 



This species, or at any rate those so named at Cambridge, is iden- 

 tical with the specimen (fig. 1) of Pictet and Campiche, which, 

 together with forms like B. minimus, List., and B. attenuatus, Sow., 

 they group under the name of B. minimus. In the text they re- 

 mark that " the middle Gault of Sainte-Croix furnishes only young 

 specimens (i. e. minimus), while the Upper Gault contains principally 

 those of 35-50 millims. in length." It is just the same at Folke- 

 stone, though there is also a short and stout form of B. ultimus which 

 is frequent in the Lower Gault. At Cambridge the most common 

 form is the elongated B. ultimus ; but I would suggest that they be 

 all regarded as belonging to the same species, keeping the various 

 names as those for varieties only which differ in size and growth 

 according to circumstances and " station." 



* Another species has been named L. raphiodon ; but this is an Upper- Chalk 

 form, and the teeth appear to me to agree better with Lamna gracilis, Ag., as 

 figured by Pict. & Camp. p. 88, pi. xi. figs. 9-18. 



