SYN0D0NT1S. 



457 



45. SYNODONTTS SERRATUS. 



Riipp. Beschr. n. Fische Nil, p. 8, pi. ii. fig. 1 (1829) ; Cuv. & Val. Hist. Poiss. 



xv. p. 263 (1840) ; Giinth. Cat. Fish. v. p. 212 (1864), and Petherick's Trav. 



ii. p. 234 (1869) ; Vaill. N. Arch. Mus. (3) viii. 1896, p. 136 ; Bouleng. 



Fish. Nile, p. 372, pi. lxx. & pi. lxxi. fig. 2 (1907). 

 Pseudosynodontis serratus, Bleek. Nederl. Tijdschr. Dierk. i. 1863, p. 55. 



Depth of body 3^ to 4J times ia total length, length of head 3f to 

 4f times. Head If to 1^ times as long as broad, more or less rugose 

 above, behind the snout, the rugosities sometimes concealed under a 

 rather thick skin ; snout rounded or obtusely pointed, longer than post- 

 ocular part of head ; eye supero-lateral, 5 (young) to 11 times in length 

 of head, 2 to 4 times in interorbital width ; lips moderately developed ; 



Fig. 343. 



Si/nodontis serratus. 

 Nubia (F. N.). 1-. 



pnemaxillary teeth forming a short and broad band ; movable mandi- 

 bular teeth not | diameter of eye, 30 to 48 in number. Maxillary 

 barbel with a broad marginal membrane in its proximal third, § to 

 If times length of head, reaching between base and middle of pectoral 

 spine ; outer mandibular barbel about twice as long as inner, the former 

 with long slender branches, which may bear secondary branches, the 

 latter with tubercular ramifications. Gill-opening not extending down- 

 wards beyond root of pectoral fin. Occipito-nuchal shield rough like 

 the occiput, obtusely tectiform, 1^ to If times as long as broad, posterior 

 processes pointed or truncate. Humeral process a little longer than 

 broad, flat or with a very distinct keel, rugose, acutely pointed, extending 



