386 Prof. T. Rupert Jones— On some Fossil Esther ice. 



" Second Geological Survey of Pennsylvania : Eeport of Progress, 

 X." 1885. At pages xxviii and xxix it is stated that "most of its 

 surface is a gently rolling, higbly cultivated country of Mesozoic 

 New-Red sandstone and shale, all dipping north-westward at angles 

 varying from 5° to 15°, for 83 miles (in a straight line) along the 



river [Delaware] The Mesozoic formation is of the 



same character throughout, — an alternation of hard and soft layers 

 of reddish sand and mud, some fit for building-purposes, some con- 

 glomeratic, a few calcareous, and some (near the middle of the 

 formation) fossiliferous, containing numerous bones of large sea- 

 lizards, shells, and plants." 



2. Other North-American Estherle. 



The best of Prof. Lewis's specimens (Fig. 3a) is unlike any of those 

 from North America figured in pi. 2 of the " Monogr. Foss. Estheriae, 

 Pal. Soc." 1862. Among the woodcuts of these Estheriae, copied at 

 pp. 86-7 of the " Monograph," fig. 6 (Estheria ovata, Lea, sp. ; Posi- 

 donia multicostata, Emmons) is the nearest in shape, but differs in 

 the number of concentric riblets. Fig. 8 (E. ovata, Lea, sp. ; P. ovalis, 

 Emmons) has the concentric lines more similar, but the outline is 

 very different. My statement, that these and the other woodcuts 

 are of little or no use towards the discrimination of species, unfor- 

 tunately still holds good. I suggested at p. 91, that fig. 28 of pi. 2 

 may be the same as figs. 26 and 27, the shape being the same ; the 

 first-mentioned, however (figs. 28-30), has not only very close-set 

 concentric lines of growth, but smooth interspaces ; and fig. 31 shows 

 the same feature, sufficient to characterize a species. Unfortunately 

 we have no certainty about the interstitial ornament of the wide- 

 ribbed figs. 26, 27. Nor can we refer the reticulate ornaments, 

 figs. 32, 34, 35, 36, so much like that of the European E. minuta, 

 and fig. 33, corresponding with that of E. Brodieana, to any 

 known form from Pennsylvania, Virginia, or North Carolina. 

 Much less the ornaments shown by figs. 37 and 38 of pi. 2. These 

 isolated pieces of ornament were taken from parts and pieces of 

 badly-preserved North-American JZstherw, and probably indicate 

 five or six different species. Figs. 26 and 27 may very well repre- 

 sent one of these species, most likely one with reticulate interspaces; 

 but there is as yet no proof of this relationship. 



The following Table shows the leading characters of the North- 

 American fossil Estheria figured in pi. 2 of the " Monogr. Foss. 

 Esth. Pal. Soc." 1862:- 



Fig. 26, 27. From Prince \ 



Edward, near Rich- \ Concentric lines wide apart. 



mond, Virginia ... ) 



,, 28. Harding's pit, near ) n ,. ,. , , ,. 



■r,- , °i i Concentric lines numerous and close together. 



Richmond ) ° 



,, 29 and 30. The same Smooth interspaces. 



,, 31. Richmond The same. 



32 Richmond ^ Reticulate interspaces, like those in E. minuta ; 



'" \ probably somewhat squeezed cross-wise. 



33 Richmond i Small reticulation, like that in M. minuta, var. 

 " ' ( Brodieana. 



