BRACHTOPODA. 363 



Surface covered with elongate pustules, some of them coarse, but the greater 

 number quite fine. 



Height of an average specimen, 5 mm. ; width and length, 6 mm. 



Waverly group. Richfield, Ohio. 



Syrinqothtris Missouri, sp. nov. 



PLATE XXXIX, FIGS. 29-31. 



Shell small, cyrtiniform ; cardinal area high, slightly incurved toward the 

 apex ; lateral cardinal margin broadly rounded, rendering the definition of the 

 area quite obscure. Median fold and sinus neither wide nor highly developed. 

 Surface of both smooth. Each lateral slope with five or six low plications. 



Interiorly the pedicle-valve bears strong divergent dental lamellae which are 

 attached to the surface of the valve for fully one-third of its length. There is no 

 median septum. The transverse delthyrial plate is thin and is developed into 

 a delicate but distinct tube. Shell substance highly punctate on the inner 

 laminJB. Height of original specimen, 13 mm. ; cardinal width, 18 mm. ; 

 length, 15 mm. 



Choteau limestone. Chateau Springs, Missouri. 



Amboccelia spinosa, sp. nov. 



PLATE XXXIX, FIGS. 16-lS. 



Shell of rather large size, hinge-line straight, equaling the full diameter of the 

 valve. Brachial valve depressed convex in the umbonal region, concave ante- 

 riorly, with upturned margins. Medially there is a low and indistinct elevation 

 which disappears toward the front. Pedicle-valve not known. Surface bearing 

 faint traces of concentric lines and covered with numerous elongate depressions 

 which were probably bases of insertion of epidermal spinules. 



Length of original specimen, 7 mm. ; width in the hinge, 9 mm. 



Hamilton shales. Livonia Salt Shaft, Livingston county, N. Y. 



