6m 



of the shell; volutions five and a half or more, increasing very grad- 

 ually in size, diameter from ventral to dorsal side nearly or quite equal- 

 ing their transverse breadth — all rather deeply embracing, so as to 

 conceal more than half of each inner turn. Surface ornamented by 

 distinct rounded costiB, which occasionally bifurcate near the umbilicus 

 and about half-way across toward the periphery, in crossing which they 

 curve slightly forward ; depressions between the costfe generally about 

 equaling the latter in size, but, at intervals of about five or six times to 

 each turn, a deep sulcus or constriction is seen on internal casts, 

 produced by the occasional thickening of the lip, at regular intervals 

 of about every fifth of each turn. A single row of small transversely- 

 elongated nodes surrounds the umbilicus. 



Septa deeply divided into six or seven principal lobes on each side, 

 which diminish regularly in size from the first lateral lobe to the um- 

 bilicus. Siphonal lobe about the size of the first lateral sinus, oblong 

 in form, and provided with three principal branches on each side, the 

 two terminal of which are larger than the others, and each irregularly 

 subdivided into two or three small branchlets and a few sharp digita- 

 tions. First lateral sinus deeply divided at the extremity into two sub- 

 equal parts, and provided on each side behind these with two or three 

 irregular alternating lateral branches — the two terminal divisions being 

 much larger than the others, and each irregularly tripartite, with sinu- 

 ous and digitate margins. First lateral lobe about the size of the first 

 lateral sinus, palmately divided at the extremity Into three large irregular 

 branches, with each three or four sharp unequal digitations at the end ; 

 while above these terminal divisions, the sides of the lobe are each 

 ornamented by two or three smaller alternating sinuate lateral branches. 

 Second lateral sinus smaller than the first lateral lobe, and having on 

 each side two or three irregular alternating lateral divisions, while 

 the extremity is divided into two unequal terminal branches, each 

 of which is again divided into two or three small branchlets, with sin- 

 uous margins. Second and third lateral lobes much smaller than the 

 first lateral, but somewhat similarly branched, their divisions being, 

 however, proportionally shorter. The three or four remaining lobes are 

 very small, a little oblique, and merely digitate, 



The specimen from which the foregoing description was made out 

 measures 2.28 inches in its greatest diameter and 0.90 inch in con- 

 vexity. As it consists entirely of septate whorls, it is probable that the 

 outer volutions of adult individuals may vary somewhat in their ex- 

 ternal ornaments, as well as in the details of their septa, from the speci- 

 men under examination. 



In form and other external characters, this species is nearer like 

 A. mutaMlis of Sowerby (Min. Couch., iv, 145, pi. 405) than any other 

 shell with which I am acquainted. I have not had an opportunity to 

 see the septa of that species ; but if it is, as some think, not distinct 

 from A. Koenigii, Sowerby, our Vancouver species may be readily dis- 

 tinguished by its more deeply-lobed septa. 



Named in honor of Prof. John S. Newberry, State geologist of Ohio, 

 and professor of geologv in the School of Mines. Columbia College, New 

 York. 



Locality and jposition. — Same as last. 



these Cephalopoda have not yet been classified, however, in accordance with the prev- 

 alent modern views, and I have not the necessary material at hand to determine the 

 exact relations of our species to some of the proposed genera, I have concluded to leave 

 part of them, for the present, under the old genus Ammonites, as understood in. its m6st 

 comprehensive sense. 



