PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 425 



It seems desirable to state that the proportions in this species differ 

 very considerably with individuals. 



Eadlal formula.— D. IX, 11; A. Ill, 8; V. I, 5; C. 9, 8; P. 16. 

 Scales: L. lat. 39; L. trans, -j^f. 



12. Calamus arctifrons, n. sp. 



A species belonging to Calamus of Swainson. The type numbered 

 30163 is a specimen 9i inches long, collected at Pensacola, Florida, by 

 Mr. Silas Stearns. 



Body oblong ovate, more elongate than is usual in species of this 

 group, deepest at origin of dorsal, the greatest depth being contained 

 nearly 2^ times in the total length to caudal base. Anterior profile 

 evenly curved, unusually convex. A blunt protuberance before eye. 

 Mouth comparatively large, the maxillary barely reaching the vertical 

 from front of orbit. Length of upper jaw contained 2^ times in head. 

 The anterior teeth of both Jaws are conical, rather strong and canine- 

 hke, 6 to 8 in each jaw. Behind these are bands of cardiform teeth. 

 Molars rather large, in two rows anteriorly and three posteriorly in 

 upper jaw ; two rows in the lower ; the molars of the inner series of both 

 jaws much larger than the others. Lower jaw slightly included. Be- 

 hind the upper lip on each side is an enlarged oblong pore, two-thirds 

 as long as the posterior nostril; above it is a fleshy flap. The posterior 

 nostrils slit-like and much larger than the circular anterior ones. Pre- 

 orbital very deep, its depth, from eye to angle of mouth, contained 3^ 

 times in length of head. Eye rather small, placed very high, its diam- 

 eter contained 3f times in length of head, and equaling four-fifths of 

 the convex interorbital space. Cheeks with 5 to 6 series of scales. 

 Four rows of scales on the opercle. Opercle very short, its length 

 equaling two-thirds diame ter of eye, and less than one-third of its 

 height. Gill-rakers very short, thickish, few. Least depth of tail two- 

 thirds length of caudal peduncle and contained 3^ times in head. 



The length of the head is contained 3i times in total to caudal base. 

 Interorbital space contained 3^ times in length of head. The oblique 

 distance from snout to origin of spinous dorsal is slightly less than half 

 the total length to caudal base. Dorsal spines slender, the longest 

 (fourth) contained 3|- times in length of head and about equal to long- 

 est ray of second dorsal. 



Distance from front of anal to base of caudal contained 3y times in 

 total. xVnal spines small, graduated, the third one-fourth as long as 

 head. The second spine somewhat stronger, but shorter, than the third. 



Caudal deeply forked, its middle rays two-fifths as long as the outer. 

 The upper lobe is nearly as long as the head. 



Pectoral narrow, reaching slightly past vent, as long as head. 



Ventrals inserted slightly behind pectoral origin, five-eighths as long 

 as the head. A partly-concealed procnmbent spine before the dorsal. 

 First spine less than two-fifths as long as second, which is not much 

 shorter than the third. 



