Maryland Geological Survey 375 



a ventral crest, the aperture sinuous laterally, convex dorsally and more 

 or less linguiform ventrally; external surface striated with incrementals 

 or even corrugated with simple or nodose costae; septa? symmetrically 

 divided commonly into six principal lobes and saddles, all of them digi- 

 tate. Baculites like Pachydiscus is confined to the Cretaceous, although 

 closely allied ancestral types with less complex sutures have been described 

 from the Jurassic faunas. 



Baculites ovatus Say 



Plate XII, Figs. 2, 3 



Baculites ovata Say, 1820, Am. Jour. Sci., 1st ser., vol. ii, p. 41. 

 Baculites ovata Morton, 1828, Jour. Acad. Nat. Sci., Phila., 1st ser., vol. vi, 



p. 89, pi. v, figs. 5, 6. 

 Baculites ovatus Morton, 1830, Am. Jour. Sci., 1st ser., vol. xvii, p. 280; 



vol. xviii, p. 249, pi. i, figs. 6-8. 

 Baculites ovatus Morton, 1830, Jour. Acad. Nat. Sci., Phila., 1st ser., vol. 



vi, p. 196, pi. v, figs. 5, 6; pi. viii, figs. 6-8. 

 Baculites ovatus Morton, 1834, Syn. Org. Rem. Cret. Group, U. S., p. 42, pi. 



i, figs. 6-8. 

 Baculites ovatus Marcou, 1853, Explan. Text to Geol. Map of TJ. S. and 



British Prov. N. A., p. 46, pi. vii, fig. 5. 

 Baculites ovatus Hall and Meek, 1856, Mem. Am. Acad. Arts and Sci., new 



ser., vol. v, p. 399, pi. v, figs, la-lc; pi. vi, figs. 1-7. 

 Baculites ovatus Meek, 1864, Check List Inv. Fossils, N. A., Cret. and Jur., 



p. 23. 

 Baculties ovatus Conrad, 1868, Cook's Geol. of New Jersey, p. 730. 

 Baculites ovatus "White, 1875, U. S. Geol. and Geog. Bxpl. and Survey, w. 



100th Merid., p. 199, pi. 19, figs. 4a-4c, 5a-5c. 

 Baculites ovatus Meek, 1876, Rept. Inv. Cret. and Ter. Fossils, Up. Missouri, 



p. 394, pi. xx, figs, la-lb, 2a-2d. 

 Baculites ovatus Whiteaves, 1889, Cont. Can. Pal., vol. i, p. 181. 

 Baculites ovatus Whitfield, 1892, Mon. U. S. Geol. Survey, vol. xviii, p. 275, 



pi. xlvi, figs. 3-9. 

 Baculites ovata Say, 1896, Bull. Am. Pal., vol. i, No. 5, p. 19 (289). (Re- 

 print, Harris.) 

 Baculites ovatus Johnson, 1905, Proc. Acad. Nat. Sci., Phila., p. 26. 

 Baculites ovatus Weller, 1907, Geol. Survey of New Jersey, Pal., vol. iv, p. 

 821, pi. cix, fig. 5. 



Description. — " B. ovata, elongated; transverse septa subovate, six- 

 lobed and a smaller one behind ; lobes of the superior faces of the septa 

 three on each side, with a minute one between each, dentated at their 

 edges, anterior lobe (nearest the siphuncle) small not sinuous, second lobe 



