F- A U A 1 . E(^. OCEK A 8. 99 



Genus Paralegoceras Hyatt. 



Tliis g-euus was descu-ihed by Hyatt" ti» include forms similar in 

 niiun- respects to Gastrioceras, but with more liig-hl}- arched whorls, helmet- 

 shaped rather than trapezoidal in outline, narrower umbilici, and less 

 ])r<)uounced sculpture. The septa are of the lanceolate type, both lobes 

 and saddles being- narrow and long-, the saddles being rounded and club- 

 shaped, while the lobes are pointed and tongue-shaped, or mucronate. 

 The lobes on each side are four in number — an e.xternal or ventral 

 two laterals, and an auxiliary lobe just on the umbilical Ijorder. There 

 are three internal or dorsal lobes — a long, pointed antisiphonal flanked 

 liy two similar laterals. This gives for Fandegoccms eleven lobes in all, 

 one pair more than Gastrioceras posesses. 



The type chosen was P. ioivense Meek and Wortheu. 



Paralegoceras baylorense White. 



PI. IV, tigs. 9-11. 



IbtU. Cruiiiatltcs haylorensis, C. A. '\^'hite, Bull. U. 8. Geol. 8urvey No. 77, p. 19, 

 PI. II,-figs. 1-3. 



The following description is quoted from White's paper: 



8hcll apimrently reaching- a moderately large size; its transverse diameter less 

 than that of the plane of its coil; volutions moderately embracing; the peripheral 

 and lateral portions reguiarU' rounded from the border of one umbilicus to that 

 of the other; umbilici deep and somewhat narrow, but showing a portion of each of 

 the inner volutions, their borders abruptly rounded inward from the sides; the 

 transverse diameter of the volutions nearly three times as great as the dorso-ventral 

 diameter, a transverse section of them showing a lunate outline. Living chamber 

 and aperture unknown. 8epta moderately distant from one another; doi-sal [ventral] 

 lobe longer than wide, deeply divided into two narrow, lanceolate, slightly diverging 

 branches; dor.sal [ventral] and superior lateral saddles linguiforni and nearly equal in 

 size; the two saddles separated by the superior lateral lobe, which is simple, slightly 

 constricted in the middle, and acuteh' pointed; the inferior lateral lobe similar in 

 shape to the superior, but a little shorter and less distinctly constricted; inferior 

 lateral saddle a little shorter than th(> others, somewhat irregular in shape, and 

 occupying the margin of the uml)irnus. Surface apparently unornamented. 



The only specimen in the collection, when perfect, probably reached a diameter 

 of coil of about 55 millimeters. 



This species bears considerable resemblance to the G. glohulosiw of Meek and 



«Proc. Boston Soc. Nat. Hist., Vol. XXII, p. 327. 



