NO. 1229. CA MBRL 1 X BRA CHIOPODA— WA L CO TT. 675 



sandstone spots that occur within the gray sandstone at Sulurp. I am 

 not sure that the dorsal valve illustrated actuall}^ belong's to this spe- 

 cies, as it is not associated with the typical ventral valve. 



It differs from the typical dorsal valves of O. moltergim being- more 

 acuminate, and there is no corresponding ventral valve associated with 

 it in the material studied. 



I take pleasure in naming the species in honor of Dr. G. Lindstrom, 

 to whom all paleontologists are deeply indebted for his many contri- 

 butions to the paleontology of the Silurian formations of Scandinavia. 



Fonnation and locality. — Lower Cambrian. Zone of Schmidtia 

 tordUi Bjorkelunda, south of Simrishamr. in a gray sandstone. Sularp, 

 near Lund, Sweden, in a brown sandstone. 



GLYPTIAS, new subgenus. 



The subgenus Glyptias is based on the peculiar surface sculpture and 

 the very short area. 



Type. — Oholella i^Glypt las) favosa Linnarsson. 



OBOLELLA (GLYPTIAS) FAVOSA Linnarsson. 



Lingula {?) favosa Linnarsson, Ofversigt af Kongl. Yetenskai^s-Akad. Forhand- 

 lingar, Ko. 3. Oin nagra forsteningar fran A'estergotlands sandstenslager, 

 p. 356, 1869. Also the English translation, published as a pamphlet, p. 16. 

 Stockholm, 1869. 



General form ovate, with the ventral vah'e subacuminate and the 

 dorsal valve obtusely rounded; valves moderately convex. The dorsal 

 valve is abruptly curve:^ downward at the beak to the plane of the edge 

 of the shell, while the beak of the ventral valve is slightly al)ove 

 the margin, the posterior edges of the shell curving up to meet it, 

 and thus forming a passage for the pedicle out of a narrow pedicle 

 slit. Surface of the shell marked by very line concentric lines or stride 

 of growth, crossed transversely by undulating, slightl}' lamellose lines 

 in almost identically the same manner as in OTxdus ( Wcstoalii) stoneanus 

 of the Upper Cambrian of AYisconsin. When the outer surface of 

 the shell is exfoliated or worn oft' by attrition, which is the usual 

 condition, the surface of the inner laj^ers shows line, radiating, and 

 concentric striaB. The shell is formed of a very thin, highl}" orna- 

 mented outer layer and numerous inner la^'ers or lamellae; the latter 

 over the anterior portions are oblique to the outer layer, and when the 

 shell is partially exfoliated they appear as imbricating layers, very 

 much as in Obolus matinalls. 



The largest ventral valve in the collection has a length of 7 nmi. and 

 a width of 6 mm. An associated dorsal valve 6 mm. long has a width 

 of 6.25 mm. 



The area of the ventral valve is narrow and rises slightl}^ to meet 

 the beak, which is elevated above the posterior margin. The pedicle 



