292 Professor T. Btqoert Jones — Triassic Estherice. 



Series, eight miles west and three miles south of Hunnewell, Sumner 

 County, Kansas. 



Two of the longer and one of the shorter forms are here figured. 







Fig. 1. — Oblique -oblong, deeper in front than behind ; umbo forward and rather 



prominent ; dorsal margin nearly straight or very slightly convex ; ventral 



margin elliptically curved, full in the anterior region. Measures 4-5 mm. in 



length, and 2-5 nim. in height. Magn. 4 diam. 



Fig. 2.— Smaller forra, subquadrate, roimded behind, subtruncate in front, probably 



a young condition. It measures 25 by 2-0 mm. Magn. 4 diam. 

 Fig. 3.— The interior of the mould or hollow cast of a larger and more oblong 



variety. Magn. 4 diam. 

 Fig. 4. — Irregular and variable siliceous deposit among the sand-grains. Magn. 

 30 diam. 

 Among the specimens some have the following different measure- 

 ments, but all appear to belong to one species : 5 X 3 mm. ; 

 4'5 X 2-5 mm. ; 4 x 3 mm, ; 4 x 2-5 mm. ; 2 5 X 2 mm. 



Of the published forms the one that approaches most nearly this 

 EstJieria from the Eed Beds of Kansas is shown by fig. 1, pi. ii, 

 " Monograph Foss. Estherige," Pal. Soc, 1862, and described at 

 p. 57, etc. This measures 55 by 3-6 mm., and is rather higher 

 in the posterior region than the sketch, Fig. 1, here given. 



The smaller form (Fig. 2) has an analogue as to shape in fig. 4 

 (5-3 by 4-0 mm.), and as to shape and size in fig. 14 (2-5 by 1-8 mm.) ; 

 also in the somewhat similar young, sexual, or varietal forms of 

 other species. 



We may also compare the larger of the first two sketches with Fig. 3, 

 PI. XI, Geol. Mag., Dec. IV, Vol. IV (1897), described at p. 290 

 (Estheria Mawsoni, from the Cretaceous strata of Brazil) ; but here 

 the antero-ventral region is too prominent. Its interstitial ornament 

 is of a har pattern, of which we have no indication in the Kansas 

 specimens. It measures 5-3 by 3'6 mm. 



The figs. 26 and 27 of pi. iii, " Monogr. Foss. Esth. " (about 

 5-3 mm. in length), approach in shape, and they exhibit good 

 examples of the prominent umbo ; but their interstitial ornament 

 is bar-like. 



Estlieria Lewisii, J., from Bucks Co., Pennsylvania (Geol. Mag., 

 Dec. Ill, Vol. VII, 1890, p. 385, PL XII, Figs. 3a, b), measures 

 5 by 3 mm., and is too broadly and fully curved on the ventral 

 margin, and too high in the posterior region, to match the 

 Kansas form. 



