820 CRETACEOUS PALEONTOLOGY. 



1892. Ammonites complexus Whitf., Pal. N. J., vol. 2 (Monog. 



U. S. G. S., vol. 18), p. 249, pi. 41, fig^. 5-7. 

 Compare : 

 1852. Ammonites flaccidicosta Roem., Kreide. von Texas, p. 



33> pl- I. %s. I a-b. 

 1 86 1. Afimwnites flaccidicosta Qahb, Synop. Moll. Cret. Form., 



p. 66 (10). 

 1864. Ammonites Hacidicosta Meek, Check List Inv. Foss. N. 



A., Cret. and Jur., p. 24. 



Description. — This species is represented in the New Jersey- 

 collections only by fragmentary specimens, too incomplete to 

 admit of a complete description. The shell is apparently some- 

 what compressed subglobular, with a broadly rounded venter, 

 and an umbilicus of moderate size, the inner volutions being cov- 

 ered by the outer ones for from one-third to^ one-half their width; 

 surface marked near the umbilicus by a row of small, trans- 

 versely elongate nodes which, on the outer volution of the larger 

 specimens, extend outward and bifurcate, to form a series of 

 rather distant, more or less obscure costse, which, with others 

 intercalated between, pass over the periphery ; the septa are very 

 complex and closely crowded. 



The diameter of the largest example observed from New Jersey 

 must have been nearly 60 mm. when the shell was complete, but 

 it is too imperfect to^ admit of accurate measurement. 



Remarks. — Whitfield has illustrated a fragment of an ammon- 

 ite which he has referred to this species, and in the recent col- 

 lections of the Survey fragments of another individual have been 

 collected from the Wenonah sand near Marlboro. The locality 

 and horizon of Whitfield's specimen cannot be determined. The 

 Wenonah sand specimen resembles somewhat closely, in sO' far 

 as it is preserved, a specimen in the National Museum at Wash- 

 ington, from the Ripley horizon at Chatfield, Texas, which is 

 labeled A'mm,omtes flaccidicosta Roem., and it is possible that the 

 New Jersey specimens should be referred tO' that species rather 

 than to complexus. Both of these species are apparently mem- 

 bers of the genus Pachydicits. More perfect material is necessary 



