142 CRETACEOUS AND TERTIARY FISH. 



variation in striae only due to greater width or depth of grooves 

 separating them, and entire surface evenly smooth to touch. As 

 spine narrows occasionally, two will unite and then continue 

 singly. Striae vary 35 to 45 in number. Length (damaged) 87 

 mm. Diameter 14 mm. 



All the smaller examples exhibit about 35 or 36 striae, while 

 in the largest there are 45. Allowing for the flutings, which are 

 not over 10, the variation is considerable. 



Formation and locality. The types, three fragmentary spines 

 from the "Cretaceous near Pemberton" [may mean the Navesink- 

 Hornerstown marl just west of Pemberton at Birmingham, the 

 Vincentown limesand nearer town, or the Manasquan marl, ex- 

 posed in the banks of the creek at Pemberton, K.], in Burlington 

 County (W. Taylor), and four small fragmentary spines from the 

 Eocene marl of Farmingdale in Monmouth County (A. J. 

 Smith). 



Cyundracanthus acus (Cope). 



Ccelorhynchus acus Cope, Proc. Amer. Philos. Soc. Phila., XII, 1870, p. 294. 



Eocene Marl of Farmingdale, Monmouth Co., N. J. 

 Cylindracanthus acus Hussakof, Bull. Amer. Mus. Nat. Hist., XXV, 1908, 



p. 44, fig. 1 (type). 



Fragment of small spine with single median cavity, and exter- 

 nally 19 ridges separated by narrow grooves. Length about 29 

 mm. (From Cope.) 



Cope originally states this to be a portion of the muzzle of a 

 fish similar to C. rectus, but smaller, also much smaller than C. 

 ornatus, and differing from the latter in much fewer ridges. 



Formation and locality. The type, described above, from the 

 Eocene marl of Farmingdale in Monmouth County (A. J. 

 Smith), and now in the American Museum at New York. 



