22 OLAF HOLTEDAHL. [SEC. ARCT. EXP. FRAM 



larger shells is about 20, usually with 3, — sometimes more — in the 

 sinus, and 4 — sometimes more — in the fold. 



I thought at first that this form was identical with S. deckerensis 

 WellerI from the Decker Ferry of New Jersey and the Keyser of 

 Maryland but as I have had an opportunity of comparing it with speci- 

 mens from Maryland in Prof. Schuchert's collection in the Peabody 

 Museum in New Haven, I have observed that there is some difference, 

 although very minute. The Arctic form is distinguished by a little more 

 acute, less globose beak, and by a distinctly deeper sinus and higher fold. 

 Furthermore the number of plications in the sinus is nearly always 3, 

 sometimes more; while in Stenochisma deckerensis the usual number is 

 2, very seldom 3. While we generally find these distinctions, I have seen 

 specimens from both localities so alike that it would have been impossible 

 to distinguish between them if they were found alone. The Ellesmereland 

 form may well be regarded as a northern representative of the other one. 



Occurrence: B, lower part, Reindeer Valley (a few, small speci- 

 mens). B, upper part, over the fragment limestone, Valley south of 

 Borgen. 



Camarotoechia Hall and Clarke. 

 Camarotoechia litchfieldensis Schuchert var. angustata nov. var. 



PI. Vfff, fig. 1. 

 A single but complete specimen, showing a close relation to the 

 narrower specimens of Camarotoechia litchfieldensis Schuchert from 

 the Keyser of Maryland, as for instance depicted in the "Lower Devonian" 

 of the Geological Survey of Maryland (pi. 63, figs. 11 — 14) yet it exhibits 

 a still narrower outline and furthermore a larger size than the small 

 form mentioned. The number of plications is about 15 in each valve, 

 3 in the sinus of the ventral, 4 in the fold of the dorsal valve. Greatest 

 length of the shell 12 mm., width 10 and thickness 8 cm. 



Occurrence: B, upper part, in the fragment-limestone, Valley 

 south of Borgen. 



Uncinulus Bayle. 



Uncinulus septentrionalis nov. sp. 



PI. VIII, fig. 3. 



There are two well-preserved specimens of this form both showing 



nearly the same size: length 10 mm., width 8, thickness in one 5, in the 



1 See .S. Welleb, Geol. Survey of New Jersey. Report on Paleontology. Vol. 3, 

 p. 2.34-, pi. 21, figs. 1-4, 1903. T. P. May.xabd, Geol. Snrvey of Maryland. Lower 

 Devonian, p. 349, pi. 63, figs. 1-4, 1918. 



