Rathbun.] 28 [May 16, 



Spirifera Elizse Hartt, MS. 



Rathbun, Bull. Butf. Soc. Nat. Sci., i, no. 4, p. 239, plates viii and 

 IX, 1874. 



Although this species resembles very much S. Pedroana in some of 

 its varieties, intermediate forms to unite the two are wanting. This 

 form is quite rare in the Devonian sandstone of Erere, the only lo- 

 cahty in which it has been found. (Morgan Exs., 1870 and '71; 

 Geol. Comm., 1876.) 

 Spirifera Buarquiana, sp. nov. 



Shell attaining a large size, gibbous, transverse, subelliptical in 

 outline, and with the breadth nearly two and one-half times the 

 length ; hinge line much shorter than the width of the shell ; surface 

 plicate. 



Dorsal valve most convex near the middle, the surface first rising 

 abruptly upward along the fold from the beak, for a short distance, 

 and then arching strongly and quite regularly to the front margin. 

 From the median fold to the lateral margins, on either side, the sur- 

 face slopes very regularly and is nearly straight. The entire poste- 

 rior part of the valve on both sides of the median line is very much 

 inflated, and the slopes from there toward the hinge line are very ab- 

 rupt. Beak very small and scarcely elevated above the hinge. Fold 

 of medium size and enlarging with moderate rapidity toward the 

 front, flattened on top and with its sides straight and abrupt. Its 

 width above equals about one-half its width at the base, and its 

 height at the front equals about one-third its width at the same point. 

 On each side of the median fold are eight prominent, regularly 

 rounded, simple plications, separated by slightly narrower, rounded 

 depressions. There exists toward the front a single, well defined 

 line of growth. Length of valve about 25 mm. or slightly more, 

 breadth about 64 mm. 



The large dorsal valve, above described, has been taken as the 

 type of the species. Not being perfect it was impossible to entirely 

 complete the description of the shell. There are besides the speci- 

 men described five or six dorsal and ventral valves of smaller size, 

 which, though they present in a general way the characters of this 

 species, yet diflFer so much from it in some details, as to render their 

 identification with it somewhat uncertain. These forms are all from 

 the Devonian sandstone of the Rio Maecuiii. (Geol. Comm., 1876.) 



I take pleasure in dedicating this species to Dr. Buarque de Mace- 

 do, chief of the department of Public Works of Brazil, to whom Sci- 



