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NEW YORK STATE MUSEUM 



Hudson valley — a very varied fauna of some thirty species, the 

 most striking elements of which are new eurypterids (nine species).- 

 There were also some mollusks and half a dozen species of 

 brachiopods. To the latter we refer the peculiar and rather puz- 

 zling fossil here described, for it resembles most nearly the internal 

 mold of the pedicle valve of a Lingulasma. Its posterior portion is 

 unfortunately broken. 



Description. The valve is elongate linguiform in outline, widest 

 in the posterior third and somewhat contracted anteriorly of the 

 middle. The platform is distinctly shown. Its central part appears 



in the mold as a broad pentagonal shield, 

 which in the middle is divided by the low, 

 broad, rounded septum that extends to 

 the anterior third of the valve. Along 

 the anterior margin of the platform a 

 triangular space is depressed or beveled, 

 indicating that this part of the platform 

 was slightly elevated above the re- 

 mainder. The lateral muscular scars 

 are distinctly set off along both lateral 

 margins of the platform and beyond this 

 is a convex rim, the mold of the concave 

 margin of the valve. The anterior part 

 of the mold exhibits a flat margin, prob- 

 ably the impression of the thick valve, 

 which, like all calcareous shells in shale, 

 has been completely dissolved away, leaving only a tenuous car- 

 bonaceous film. The anterior half of the mold is uniformly convex, 

 with the exception of a faint depressed transversal band, probably 

 due to the gerontic thickening of the shell. 



The valve is about 33 mm wide in the contracted part and about 

 39 mm in the widest. Its length, so far as preserved, is 52 mm. 



Horizon and locality. Schenectady beds at the Dettbarn quarry 

 near Schenectady, N. Y. 



Remarks. From its two congeners, Lingulasma schu- 

 c h e r t i Ulrich and L. galenaense Winchell & Schuchert, 

 our species is readily distinguished by its more elongate form, 

 larger size, posterior widening and the peculiar shape of the 

 anterior part of the platform. 



Fig. 31 Lingulasma 

 (?) elongatum nov. 

 Holotype. Natural size 



