189 



Cephalopoda. 



Ammonoidea. 

 Macroceplialites. v. Sütner. 



Group of MacrOCephalites Ishmæ. Keyserling, sp. 

 Macroceplialites Pompeckji. nov. sp. 



PI. VITI, figs. 5 and 6. 



Five more or less perfect clay-ironstone casts of Ammo- 

 nites have been collected by 0. Nordenskjold on Ammonite 

 Mountain on the west side of the innermost part of Hurry's 

 Inlet, from a height of 500 metres above sea-level. These 

 belong to the genus Macroceplialites and to the group of 

 Macroceplialites Ishmæ Keys. sp. 



The largest fragment has a diameter of 81™°^; the best- 

 preserved has a diameter of 75™" in the widest part that can 

 be measured. 



In this same specimen the actual measurements and pro- 

 portions, taken where the diameter measures 70"""*, are the 

 following: — 



Diameter = 70°"^ = 1 



Width of umbiUcus = 9 ,> = 0.13 



Height I [ = 33 .) = 0.47 



^, . , J of last whorK „^ 



Thickness] ( = 32 » = 0.46. 



Measurements of the same specimen taken at right angles 



to the above, gave the following results and proportions: — 



Diameter =^ бг'"'" = 1 



Width of umbihcus = 7 » = 0.11 



Height ) r = 31 ., = 0.50 



^, . , } of last whorH „_^ ^ ^^ 



Thickness] ( = 30 » = 0.48. 



The whorls are broadly convex on the sides and on the 

 external margin, but curve down steeply and abruptly towards 

 the umbilicus. The greatest thickness of the whorls occurs at 

 a little below half their height. The whorls are approximately 



