296 2IisceUaneoHs. 



Skeleton of paired fins. — Tho post-temporal is forked, 

 attached to the epiotic above and the opisthotic biilow ; the 

 lijpercoracoid is perforate and tlie hypocoracoid is narrowed 

 forward below, meeting the cleithriim at or above the sym- 

 physis ; there is no mesocoracoid ; there are 4 liourglass- 

 shaped radials, only the lowest on the hypocoracoid ; the 

 post-cleithruni is single, laminar above, and slender and rod- 

 like below ; the pelvic bones are connected with the post- 

 cleithra ; tliey are formed of transverse portions which 

 broadly overlap and are nnited, and of rather slender pro- 

 cesses wiiich converge anteriorly (tig. A). 



Two families may be recognized: — 



1. Percopsidae. 



An adipose fin. (yandalof 19 principal rays, 17 branclied ; 

 pel vies b-rayed. Ve it just in front of anal fin. Palate 

 toothless. Vertebrae 34 to 36 (16-17 + 17-19). 



Two genera : Percopsis and Columbia. 



2. Aphredoderidae. 



No adipose fin. Caudal of 18 principal rays, IG branched ; 

 pelvics 7-rayed. Vent at tlie throat (in tlie adult). Teeth 

 on vomer and palatines. Vertebrai 30 (13 + 17). 



A single genus : Aphredoderus. 



Jordan and Evermann (Bull. U.S. Nat._ Mas. xlvli. 1S96, 

 pp. 782-786) recognize to a certain extent the relationship 

 between these two families, but make each the type of a 

 separate order ; their idea that tliese fishes may be rather 

 closely related to the Percoid families Percidte and Centrarch- 

 idae is not confirmed by a study of the anatomy. Boulenger, 

 in the 'Cambiidge Natural History' (1904), includes tiie 

 Percopsidffi in the heterogeneous group Haplomi, whilst 

 Aphredoderus is placed in tlie Berycida?. Starks (Proc. (J.S. 

 Nat. Mus. xxvii. 1904, p. 603) has noted some of the cha- 

 racters which separate Aphredo lerus from the Berycoid-s. 



MISCELLAXEOUS. 



Eoycd Institution. 



Professor Karl Pearso:^ being unable to lecture at the Eoyal 

 Institution on March 3, the Friday Evening Discourse on that date 

 ■will be delivered by Dr. F. A. Dixet, his subject being " Scents of 

 Eutterflies." 



