DIBRANCHIATE CEPHALOPODS. 



93 



it is rarely found preserved in a fossil condition, and its 

 value to the working palaeontologist is thus greatly reduced. 

 Not only is the internal skeleton of the Belemuite known, 

 but various specimens have been discovered, from which 

 much has been learnt as to other points of its anatomy. 

 Thus we know that the body (fig. 478, a) was furnished 

 with lateral fins, that there were eight arms and two longer 

 " tentacles," that the suckers were provided with horny hooks, 

 and that there was a large ink-sac, together with horny man- 

 dibles. Most of the specimens here alluded to belong to 

 BeUmnoteuthis, but Behmnites proper was doubtless built 

 upon essentially the same plan. 



Fig. 478.— A. Restoration of the animal of the Belemnite ; b. Diagram showing the 

 complete slieleton of a Belemnite, consisting of the chambered phragmacone (a), the guard 

 (6), and the horny pen (c) ; c, Specimen of Belemnites mnaliculatus, from the Inferior 

 Oolite. (After Phillips.) 



The following table of the sections and sub-sections of the 

 species of the genus Belemnites is the one given by Dr S. P. 

 Woodward : — 



