484 CALIFORNIA ACADEMY OF SCIENCES. L1I2 
Family CHAATODONTID. 
184. Chetodon humeralis Giinther. MuUNECA. 
Exceedingly common in the Astillero, especially on 
rock bottom. It reaches a length of about six inches, 
and is seldom used as food, although its striking color, 
which has suggested the name of J/ueca or doll, makes 
it an object of attention. 
185. Pomacanthus zonipectus (Gill). MojArra DE LAS 
PiepRAS. ( Pomacanthus crescentalts Jordan & Gilbert. ) 
Not uncommon in rocky places about Mazatlan. Two 
specimens were obtained by us with dynamite about the 
wreck of a French man-of-war in the Astillero. Smaller 
specimens, very different in color from the adult, and 
hence taken by us to bea distinct species ( Pomacanthus 
crescentalis), were obtained by Dr. Gilbert at Mazatlan 
and Panama. The original type of the species was taken 
at San Salvador by Capt. Dow. 
Description of the adult of Pomacanthus zontpectus: 
Head 324; depth 143)" D2 XE 23a wil 20 ene 
opercular spine longer than eye, 3% in head. Last dor- 
sal spine 1% in head. Longest dorsal ray 4 longer than 
head, falcate. Anal rounded. Caudal short, truncate, 
1% in head. Pectoral moderate. Ventral very long, 4 
longer than head. Preorbital equals maxillary, 1% in 
/ 
head. Eye 3% in head. Interopercle with one stoutish 
spine. Preopercle very finely serrate. A large hump 
at nape in adult. 
Dark gray, blackish posteriorly, most scales with black 
centers; edges of scales, bright sky blue in life, espe- 
cially posteriorly; a triangular bronze yellow patch in 
front of line connecting pectorals with ventrals, then a 
diffuse blackish bar from front of dorsal along region be- 
hind pectorals to ventrals, then a broad curved bar of 
