214 PROCEEDINGS OF THE ACADEMY OP 



I. Scales large or moderate (24 40) ; opercular bones scaly 



and not striated Pomacentrin.e. 



A. Dorsal spines 12 14. 



B. Scales in less than 30 oblique rows. 

 C. Teeth compressed, uniserial. 



* Teeth fixed, entire. 



1. Preoperculum serrated in adult Pomacentrus. 



2. Preoperculum entire ; scales in about 14 longi- 



tudinal roAvs Pomataprion. 



3. Preoperculum entire. Scales in about 20 



longitudinal rows Hypsypops. 



** Teeth fixed, more or less notched in middle. 



1. Snout acute. Preorbital low. Teeth emar- 



ginate... Glyphidodon. 



2. Snout blunt and high. Preorbital high. 



Teeth deeply notched Euschistodus. 



*** Teeth immovable, tricuspid Dischistodus.* 



**** Teeth in the upper jaw moveable Microspathodon. 



CC. Teeth conical, in more than one row. 



* Preoperculum entire , Chromis. 



** Preoperculum serrated Dascyllus. 



BB. Scales in 35 40 oblique rows. 



Preoperculum serrated Lepidozygus. 



Preoperculum entire Parma. 



A A. Dorsal spines about 17 Acanthochromuf 



I. Scales small (45 -TO). Operculum and suboperculum 



radiatedly striated Amphiprionin^e. 



* Operculum and suboperculum spinous Amphiprion. 



** Operculum and suboperculum serrated. Pre- 

 orbital with a long spine Premnas. 



Subfamily FOMACENTRINuE Gill. 



Genus POMACENTRUS Gill. 



This genus includes only two Californian species, the P. quadrigulla and P. 

 Bairdii, formerly referred to it, belonging to another. The two species rnay 

 be briefly distinguished as follows : 



Synopsis. 



I. Lower limb of the preoperculum scaly ; height nearly 

 equal to one-third of total length. Head above (in 

 youth), with a blue line on each side continued uninter- 

 ruptedly backwards to each side of the dorsal ridge ; 

 another parallel line is continued backwards from the 

 upper angle of the eye. Back of caudal peduncle with 

 ocellus. 

 a. Color similar above and below, in youth diffused blue 

 on the centres of the scales, and with a dorsal ocellus. 

 In the adult uniform purplish brown, and with no 



dorsal ocellus P. rectiframum. 



(i. Color above brownish, with blue on the centres of the 

 scales ; below the lateral line and on tail brownish 

 yellow ; and in front of latter, dottedTv'ith blue on each 

 scale. Dorsal ocellus very distinct in adult as well as 

 young P. flavilatus. 



* Type. Pomacentrus fasciatus C. et V. 

 f Type. Dascyllus polyacauthus Blkr. 



Sept. 



