Prof. T. Rupert Jones — On some Fossil Estherice. 387 



■p. 34 j) p- f Reticulation, like that of fig. 32, and probably slightly 

 " \ squeezed in the same way. 



,, 35. Dan River Similar reticulation, but squeezed obliquely. 



0fi p . , j ( Similar reticulation, either squeezed sideways, or 



" d0 ' mcamom \ naturally crossed with slight vertical ridges. 



o 7 -pv -D- ( Columnar interstitial ornament, like that in some 



" " ' \ Wealden specimens, and in the recent E. similis. 



„o t>. , , | Interspaces filled with coarse parallel thread-like lines, 



" ' 1C mon \ one separated from another by a row of small pits. 



Figs. 26 and 27 are good examples of subovate valves, with open 

 concentric ribbing, but have lost all trace of their interstitial 

 ornament ; fig. 28, though of the same shape, differs from the fore- 

 going in the closeness of its lines of growth. 



The ornamentation shows that figs. 32, 34, and 35 are decidedly 

 of one species ; fig. 33 may be a variety of the same ; fig. 36 is 

 either the foregoing large reticulation squeezed sideways, or that of 

 a different species ; fig. 37 and fig. 38 are also distinct species. 



We have no better grounds for taking these characters of imperfect 

 specimens as the basis for naming the possible species than we had 

 in 1862, when I grouped them all under Lea's name " ovata" on 

 account of the possibility of bad drawings of badly preserved 

 specimens making differences where none really exist. 



Prof. J. D. Dana, in his " Manual of Geology," 3rd edit. 1880, 

 p. 410, gives in fig. 711 a drawing like fig. 5 (Ly ell's woodcut), 

 p. 86, Monogr. Foss. Esth., for E. ovata (Lea) ; in fig. 711a, E. 

 ovalis (Emmons), like the fig. 8, p. 87, op. cit. ; and in fig. l\\b, a 

 small, neat, suboval valve (apparently the same as " Estheria ovata,'" 

 fig. 261, p. 169, " Text-book of Geology," 1870) as E. parva (Lea). 

 This is an acceptable plan, if "E. ovata " can be allowed (as in 1862) 

 to cover the group, although Emmons's multicostata was said by 

 Conrad to be the same as Lea's ovata ; the latter to be apparently 

 not the same as Ly ell's specimens (fig. 5, p. 86, Monograph, & pi. 

 2, fig. 28) ; and Emmons's triangularis (p. 86, fig. 7) to be probably 

 the same as Lea's parva. We still want perfect drawings or good 

 examples of these forms. Prof. H. Carvill Lewis hoped to get some 

 for examination ; but the specimens now before us are all that 

 opportunity permitted him to obtain before he was taken from us. 



II. Estheria minnta (Albert!) , and E. laxitexta, Sandberger, from 



Bavaria, etc. 



Some years ago my friend Dr. Fridolin von Sandberger favoured 

 me with several specimens of Estheria minuta (Alberti) and E. laxitexta, 

 Sandberger, but it has been only of late that I could take them in 

 hand for careful examination. The following have been selected as 

 specimens showing good shapes of E. minuta. 



Figs. 4, 5, and 6 are in a grey, micaceous shale, with ferruginous 

 impressions of plant-remains, from the Lettenkohle, at Fulda, 

 Hessen-Cassel. 



Fig. 4 corresponds closely with fig. 4, pi. 2, "Monogr. Foss. 

 Estheria?," 1862, but has rather weaker umbo and stronger concentric 

 wrinkles ; Fig. 5 is like fig. 29, pi. 1, but is weak in the umbo (like 

 Fig. 4), and has more numerous and less pronounced concentric 



