196 



largest end nearly circular, but compressed slightly and somewhat 

 obliquely at the sides. Alveolar cavity occupying about one half of 

 the entire length in average specimens : chambers in the phragmocone 

 very numerous and approximated: apices of both guard and phrag- 

 mocone eccenti-ic and placed nearest to the siphonal side. Apex of 

 guard in some specimens with, and in others witliout, a narrow faint 

 groove on the siphonal side. 



Length of the most perfect specimen collected : seven and a half 

 centimetres ; diameter of the same, from the siphonal to the anti- 

 8ij)honal side, at the largest end, fourteen millimetres. 



Skidegate Inlet, East side of Alliford Bay, three specimens ; also 

 South side of same bay, four specimens ; all from rocks which Dr. 

 Dawson regards as near the base of Subdivision 0. 



On page 127 of the " Palaeontology of the Upper Missouri," after 

 describing the typical form of Belemnites densus, and discussing its 

 probable affinities, the following remarks are added by Mr. Meek : — 

 " Along with these large specimens " (of B. densus) " we find several 

 smaller ones, having a proportionally more slender form and a moi-e 

 nearly central axial line. Some of these also have a quite distinct, 

 though narrow, ventral groove, while their transverse section varies 

 from subcirculai- to oblong-oval. These, we suspect, belong to a dis- 

 tinct sjjecies, but, without better and more extensive collections for 

 comparison, we have not been quite able to satisfy ourselves that they 

 may not be younger individuals of the more robust form. These two 

 varieties appear to i)ear exactly the same relations that the large and 

 small specimens of B. Panderianus, figured by d'Orbigny, do to each 

 other." In the " explanations of plate V." of the same volume, Mr. 

 Meek goes a little farther than this, and adds a statement to the effect 

 that the slender Belenuiite from Dakota, repi-escnted by figures lA and 

 l^■ of that plate, which has " a distinct ventral furrow," may possibly 

 belong to a ditterent species to those from the same locality, which are 

 equally slender but which have no ventral furrow. 



The seven specimens collected by Dr. G. M. Dawson at Skidegate 

 Inlet, and to which the name B. Skidegatensis has been provisionally 

 applied, have no distinct median ventral furrow, but only a faint apical 

 groove on the siphonal and therefore possibly ventral side. 



It is worthy of note that the short and thick form of the Belemnites 

 Panderianus of D'Orbigny, to which Eichwald has given the name 

 B. curtus, and which Meek thought that B. densus was intimately 

 related to, is regarded by Eichwald in the " Lethaea Eossica "* as a 

 Neocomian rather than a Jurassic species. 



* Volume 2, page 100. 



