Logan. I The Invertebrates, Fort Pierre Group. 511 



Scajrfiites nodosits, var. brevis Meek. Plate cvin, fig. 3. 



Scaphites (Ammonites?) nodosits Owen, 1852, Rep. Geol. Surv. Iowa, Wis., 



and Minn., 5S0, tab. vin, f. 4; Meek and Hayden, 1860, Proc. Acad. Nat. 



Sci. Phil., xn, 420: Gabb. 1861, Syn. Cret. Fauna, 32; Meek, 1864, Smiths. 



Check-List N. Am. Cret. Foss., 28. 

 Scaphiies nndnsus, var. brevis Meek, 1876, U. S. Geol. Surv. Terr., vol. ix, 



pp. 426, 427, pi. xxv, ff. la, b, c. 



Description : " Shell longitudinally oval, moderately convex ; 

 volutions generally higher than convex, inner ones forming a 

 considerable portion of the entire bulk ; deflected or body por- 

 tions high, moderately ; but short and only becoming a little 

 free at the aperture, periphery rounded throughout ; umbilicus 

 small; aperture oval subquadrate, being higher than wide, 

 and more or less sinuous on the inner side ; surface ornamented 

 by small, bifurcating costae, that are somewhat flexuous on the 

 sides, but becoming even and nearly straight on the periphery ; 

 each side of body portion also bearing near the periphery a row 

 of rather prominent, subquadrangular nodes, and a few smaller 

 ones about one-third the height from the umbilicus. 



" Septa divided into rather deep lobes, and sinuous ; siphonal 

 lobe longer than wide, nearly oblong in form, and provided on 

 each side with two principal slender branches, the two terminal 

 of which are parallel, longer than the others, and each sub- 

 divided into two unequal, variously sinuous and subdivided 

 branchlets ; first lateral lobe narrower and shorter than the 

 siphonal lobe, and provided with two nearly equal bifid and 

 sharply digitate terminal branches, and on each side with one 

 smaller, nearly simple, lateral division ; second lateral lobe not 

 more than half as long and wide as the first, but very similarly 

 branched; third lateral sinus much smaller than the second, 

 and divided at the end into two equal, slightly sinuate terminal 

 branches, with some small, obtuse, ]ateral projections; third 

 lateral lobe not longer than one of the terminal branches of the 

 second, and trifid at the end, the division being very small and 

 nearly or quite simple. Farther in there is a minute simple 

 projection, that probably represents the minute fourth lobe in 

 some of the other varieties." 



26 -iv 



