PLATE XVII. 



Fio. Page. 



1. Ctenothrissa radian* (Agassiz) ; right lateral aspect of fish, Avitli jaws dis- 



placed forwards. — Zone of Holaster subgldbosus ; Glynde, Sussex. 

 Willett Collection no. 38, Brighton Museum, a., anal fin ; ao., 

 antorbital; c, caudal fin; co., circumorbitals ; a 1 ., dentary ; do., dorsal 

 fin; iop., interoperculum ; mx., maxilla; op., operculum ; pet., pectoral 

 fin; plv., pelvic fin; pop., preoperculum ; pit., post-temporal; qu., 

 quadrate ; smx. 2., posterior supramaxilla ; sop., suboperculum ; st., 

 supratemporal. 79. 



2. Ditto ; head with opercular apparatus, right lateral and superior (2 a) 



aspects, with right premaxilla (2 h) enlarged three times. — Probably 

 from a Turonian zone ; Kent. Harford Collection (B. M. no. P. 5G99). 

 eth., mesethmoid; fr., frontal; pmx., premaxilla; scl., supraclavicle ; 

 smx.l, 2., anterior and posterior supramaxilla; other letters as in 

 fig. 1. 79. 



3. Ditto ; right maxilla, inner aspect. — Probably from zone of Holaster 



subglobosus ; Burham, Kent. Mrs. Smith's Collection (B. M. no. 

 49052). 79. 



4. Ditto ; portion of branchial arch with gill-rakers. — Probably from a 



Turonian zone; Cuxton, Kent. Harford Collection (B. M. no. 



P. 5G85). 80. 



o. Ditto ; portion of pectoral and pelvic arches, right lateral aspect. Zone 

 of Holaster subglobosus; Kent. B. M. no. P. 4843. cL, clavicle; 

 cor., coracoid ; pel., postclavicle overlapped by clavicle ; plv., remains 

 of pelvic fin-support and fin ; sc., scapula. 82. 



G. Ditto ; scale of flank, inner aspect, twice nat. size, from same specimen as 



fig. 5. 83. 



All the figures, except 2b and G, of the natural size. 



