Prof. T. Rupert Jones — Fossil Estherice. 51 



by their shape and ornament ; hut those now under notice are larger; 

 one individual is approximately subquadrate in shape (Fig. 1), but 

 the other is more elongate (Fig. 2) ; both have the umbo further 

 from the anterior extremity, and otherwise differ from E. suhqua- 

 drata and E. eUiptica in being less fully curved at the antero-ventral 

 region and in being higher behind than in front. Further, they 

 have a delicate i-eticulation for the interstitial ornament (Fig. 3). 

 This finely punctate sculpture, however, belonging to the super- 

 ficial layer of the test, gives an impression on the matrix, at some 

 places, of a delicate linear granulation, making very small, vertical, 

 interrupted strife ; whilst the inside of this outer layer shows a 

 coarser pitting (Fig. 4). 



Specimens numerous, squeezed flat, but fairly well preserved, on 

 the thin lamina of a bluish grey, soft shale, with brownish partings, 

 and with white patches of the decomposed Cypridece. 



3. EsTHERiA HiNDEi, sp. nov, PI. II. Figs. 5-8. 

 Length 7 (hinge-line 5), height 4-5 mm. 



An elegant suboblong Estheria, boldly rounded in front, narrower 

 behind ; rather more than half egg-shaped in a longitudinal aspect. 

 Umbo at the antero-dorsal corner. Concentric riblets (15 visible) 

 strong and far apart, and at some spots seen to be neatly beaded, 

 but rarely so regularly and distinct as in Fig. 6. The interspaces 

 are bare of ornament ; but the inner layer of the test in some 

 instances shows irregular vertical rows of small lumpy elevations 

 (Fig. 7), which are probably exaggerations (in the older part of the 

 valve) of small vertical irregular bars (Fig. 8), in the interspaces 

 elsewhere. This last-mentioned columnar ornament is analogous 

 to that shown in fig. 37, pL ii. of the Monogr, Foss. Estherise, and 

 refei-red to at page 387, Geol. Mag. September, 1890. 



The specimens under notice are numerous in a hard, black, 

 thinly-laminated Triassic shale, from Phoenixville, Pennsylvania 

 (Dr. G. J. Hinde's Collection), like some of that described at p. 99, 

 " Monogr. Foss. Estherise," as having been supplied by Mr. C. M. 

 Wheatley from the same locality. Some are better preserved 

 as to shape : but others more distinctly show the structure of 

 the valve. The selected specimen. Fig. 5, is like one of the 

 " narrower " examples mentioned at p. 98 op. cit. ; and, as with 

 many others, there is no interstitial ornament. In some shiny, 

 black, filmy valves we have the features shown in Figs. 6, 7, 8. The 

 last two belong to the inner layer of tests of apparently different 

 ages, but covered with the outer layer, in which the ornament 

 became obsolete. Hence neither figs. 29 and 30, nor fig. 31 of 

 pi. ii. "Monogr. Foss. Esth." must be taken by themselves for 

 specific characters, though suggested at p. 386 of the Geol. Mag. 

 Sept. 1890. 



These specimens from Pennsylvania certainly differ from Estheria 

 ovata of the " Monogr. Foss. Esth." p. 84, pi. ii. figs. 26-28, being 

 proportionally longer, and having a less fully semicircular ventral 

 outline. They are larger and proportionally higher (broader) than 



