106 



The dorsal fin .appears to have had thirteen rays, of which the second was 

 the longest, and from which the others gradually decreased. The anal fin 

 contains fourteen rays. The caudal fin between its two extreme outer and 

 longest rays, inclusive of these, appears to possess twenty rays. 



The ventral carinated spines are twenty-five. Accessory ribs project from 

 the vertebrae and ordinary ribs in the usual manner in the herrings. 



Measurements of the specimen are as follows : 



Lines. 



Total length of tbe fish 45 



Length to commencement of the tail 34 



Depth of body in front of dorsal fin 10 



Depth at anus G 



Length of the head 10 J 



Depth of the head 8i 



Length of the tail 10 



Depth of pedicle of the tail 4 



Distance from snout to commencement of dorsal flu 17 



Distance from snout to anus 27 



Clupea alta. 



A slab of shale obtained from the so-called "Petrified Fish Cut," and sub- 

 mitted to my examination, contains ten herrings, in which the bones and 

 scales are preserved, and stained of a dark-brown hue. The vertebras, where 

 broken, exhibit the position of a continuous notochord occupied by hyaline 

 chalcedony that looks like the original substance of the latter itself. The 

 most complete and largest of the fossil-fishes is represented of the natural 

 size in Fig. 2, Plate XVII. 



These fishes appear to belong to a different species of herring from the 

 former, especially distinguished by the greater proportionate depth of the 

 body and the more arched dorsal border. In most other essential characters 

 the two appear to agree. It has the same number of vertebras and of ventral 

 carinated spines. The fins also, so far as can be determined, appear to con- 

 tain the same number of rays. 



The other specimens on the slab, though smaller, exhibit the same, or 

 nearly the same, proportionate depth of the body. 



The measurements of the specimen figured are as follows : 



Lines. 



Total length of the fish 50 



Length to commencement of tail 38 



Depth of body in front of dorsal fin 11£ 



