1918.] 



NATURAL SCIENCES OF PHILADELPHIA. 



47 



branchiae a little shorter than gill-filaments. Branchiostegal mem- 

 brane moderately free over short constricted isthmus. 



Scales finely ctenoid, narrowlj^ imbricated, in even lengthwise rows, 

 smaller along body edges, and at fin bases. Vertical fins covered 

 basally with small scales. Suprascapula entire. Cheek with 3 

 rows of scales and lowest row on preopercle limb. Lips, chin, pre- 

 orbital, suborbitals and snout edge narrowly, naked. Scales on 

 snout above and top of head all small. Upper arch of lateral line 



Fig. 18. — Pomacentrus hebardi sp. nov. 



concurrent with limit of general squamation on dorsals, and extends 

 back opposite soft dorsal origin. Tubes simple, large, extend over 

 first half in each scale exposure. Pores in straight section simple, 

 inconspicuous, and not on caudal base. 



Spinous dorsal origin opposite pectoral origin, spines graduated 

 up to fourth when largely subequal to last, fin edge notched and with 

 cutaneous flap behind each spine tip. Soft dorsal origin at last third 

 in space between hind eye edge and caudal base, and hind median 

 rays longest. Spinous anal midway between pectoral origin and 



