PRIMITIIDAE 



63 



Family Primitiidae Ulrich and Bassler 



Genus Carboprimitia 

 Croneis and Funkhouser 



Carboprimitia campa Cooper, n. sp. 



Plate 14, figures 12-15 



Carapace subovate ; hinge straight, slight- 

 1}^ depressed or channeled between notches; 

 overlap equal, complete at each end, much 

 greater along venter ; anterior furrow paral- 

 lel to free margin, merging with depressed 

 overlap area below and with flat, sinus-like 

 area in antero-dorsal quarter ; pit wide, deep, 

 antemedian, undefined around margins ; 

 cardinal area flat, except on posterior half 

 which barely rises above hinge; greatest 

 length central ; greatest height and thick- 

 ness post-central through shoulder on right 

 valve. 



Length, 1.04 mm; height, 0.70 mm; 

 thickness, 0.50 mm. 



Menard formation, locality 7, common. 



This species may be recognized by the 

 low dorsal protuberance of the right valve, 

 and the deeply channeled, very large over- 

 lap along the ventral free margin. 



Carboprimitia longula Cooper, n. sp. 



Plate 14, figures 26-29 



Carapace large, thick, elongate, surface 

 smooth ; pits deep, slightly forward of mid- 

 dle ; dorsum flat, sloping toward hinge, 

 shoulder on right valve projecting above 

 hinge ; central portion of hinge depressed, 

 channel thus formed terminated by the 

 notch of the sansabelloid articulation ; over- 

 lap complete around free margin, greatest 

 back of middle of venter ; channel, parallel 

 to and just inside anterior margin, marks 

 left valve ; greatest height and thickness 

 posterior, through shoulder of right valve ; 

 greatest length through middle of shell. 



Length, 1.10 mm; height, 0.73 mm; 

 thickness, 0.53 mm. 



Clore formation, locality 4, common. 



C. longula is similar to previously de- 

 scribed species but may be distinguished by 

 the greater length (form ratio, 1.6) and 

 by the greater depth of the pits. 



Carboprimitia rotunda 



Croneis and Funkhouser 



Plate 14, figures 16-19 



Carboprimitia rotunda Croneis and Funkhouser, 

 1938, Bull. Denison Univ., Jour. Sci. Lab., 

 vol. 33, p. 338, pi. 9, figs. 3, 4, Clore forma- 

 tion. 



Carboprimitia rotunda var. tujnida Croneis and 

 Funkhouser, 1938, idem., p. 339, pi. 9, figs. 

 5, 6, Clore formation. 



Length, 1.0 mm; height, 0.71 mm; thick- 

 ness, 0.50 mm. 



Vienna formation, locality 10, rare; Me- 

 nard formation, locality 7, abundant; Clore 

 formation, locality 4, abundant; Kinkaid 

 formation, locality 5, abundant. 



Genus Coryellina Bradfield 



CORYELLINA ELEGANS 



(Croneis and Gutke) 



Plate 14, figures 34-36 



Perprimitia elegans Croneis and Gutke, 1939, 

 Bull. Denison Univ., Jour. Sci. Lab., vol. 34, 

 p. 38, pi. 1, figs. 3, 4, Renault formation. 



Length, 0.60 mm; height, 0.40 mm; 

 thickness, 0.40 mm. 



Renault formation, locality 9, rare. 



This species closely resembles C. capax 

 Bradfield in the general dorsal outline, 

 character of incised articulation on the free 

 margins, obesity, median sulcus, and in the 

 presence of small spines. It differs in the 

 lack of channeling of the hinge line and 

 lacks the development of the posterior end, 

 which is produced to meet the spine. In 

 C. elegans, the spine rises from the posterior 

 margin without interruption of the regular 

 curvature of the shell. 



Genus Tetrasacculus Stewart 



Tetrasacculus mirablilis 



(Croneis and Gale) 



Plate 14, figures 44-53 



Pterocodella mirablilis Croneis and Gale, 1938, 

 Bull. Denison Univ., Jour. Sci. Lab., vol. 33, 

 p. 261, pi. 5, figs. 25-27, Golconda formation. 



JVorkmanella distincta Croneis and Gale, idem., 

 p. 277, pi. 5, fig. 11, Golconda formation. 



Male: length, 0.70 mm; height, 0.39 

 mm; thickness, 0.38 mm. 



Female: length, 0.87 mm; height, 0.45 

 mm ; thickness, 0.44 mm. 



Golconda formation, locality 28, com- 

 mon; Glen Dean formation, locality 23, 

 depth 230-35 feet, common. 



