38 ACANTHOPTEEYGir. 



Snout as long as eye; maxillary exteiuliug to below anterior ^ of eye ; depth of 



body -J-S in the length; 8 gill-rakers ou the lower part of anterior arch . 4. harengulus. 

 b. Prremaxillary processes i the length of liead ; 7 gill-rakers ou the lower part of 

 anterior arch. 



Depth of body ;2i—2i in the length 5. californiensis. 



Hepth of body 3-3? in the length G. j^seudor/ula. 



E. Anal II 8 7. lefroyi. 



II. Prreopercnlum finely' serrated. 



A. Pr;eorbital entire; no conspicnous dark longitudinal lines along the series of scales. 



1. Anal III 8. 



a. Second dorsal spine from f to as long as the head. 



^laxillary extending nearly to below middle of eye (in specimens of 220 mm.) ; 



4 scales between pectoral and ventral 8. pernv'iauus. 



^Maxillary extending to below anterior ^ of eye (in a specimen of 220 mm.) ; 



3 scales between pectoral and ventral 9. olithostoinas. 



b. Second dorsal spine 5 the length of head 10. aureolus. 



2. Anal II 9 11. rhombcus. 



B. Prseorbital finely serrated ; conspicuous dark longitudinal lines along the series of scales. 

 1. Pectoral extending to, or nearly to, origin of anal. 



a. Second anal spine as long as longest dorsal spine. 

 a. Anal III 8. 

 4 scales between lateral line and middle of dorsal fin ; 15 gill-rakers on the 



lower part of anterior arch 12. lineatux. 



o scales between lateral line and middle of dorsal fin; 1.2 gill-rakers ou th 



e 



lower part of anterior arch 13. axillaris. 



/3. Anal III 7 14. paiao. 



b. Second anal spine 4-| as long as longest dorsal spine. Anal III 8. \o. plumieri. 

 2. Pectoral not extending to origin of anal. Anal III 8. 

 Second anal spine f as long as longest dorsal spine; pectoral ^-"^ the length 



ot head Ig. breinmanus. 



Second anal spine ■;. as long as longest dorsal spine ; pectoral as long as head . 17. mexicanus. 



1. Gerres cinerens, Walbaum, 1792. 



Xystmma cintrewu (part.), .lord. & Everm. Eull. U.S. Nat. Mus. xlvii. 1898, p. 1372, and 1900 

 fig. 556. 



Hah. Atlantic Coasts from Florida to Brazil ; freshwater ponds of Barbados. 



2. Gerres simillimus, sp. n. (Tab. Vlll. fig. 2.) 



XyslcEina cineremn (part.), Jord. & Everm. 1. c. 



I.'epth of body -j-l';! in the length, Iriiglli of head 3 to 3]. Snout as long as or longer than eye, the 

 diameter of whieh la more than .] the length of liead ; interorhital width 2,3 to 3 in the length of head. 

 Maxillary extending to below anterior J of oyo. f'noorbital and pra-opcrculnm entire. 8 gill-rakers 

 on the lower part of the anterior arch. 40-43 scales in a longitudinal series, 4 between lateral line and 



