PBOTOPTE.KTJS. 19 



Fam. 1. LEPIDOSIRENID.E. 



Body elongate, covered with thin cycloid scales. Dorsal and anal 

 fins formed of very numerous fine rays. Paired fins reduced to a slender 

 segmented axis with or without a unilateral fringe. Dentition consisting 

 of sharp ridges of dentine covered with enamel and continuous with the 

 vomerine, palatopterygoid, and splenial bones. Nostrils under the upper 

 lip, concealed when the mouth is closed. Young with external gills. 

 Lungs paired, elongate, attenuate posteriorly. 



Two genera : Protopterus in Africa, and Lepidosiren in South America. 



1. PROTOPTERUS. 



Owen, Proc. Linn. Soc. 1839, p. 27 ; Peters, Reise Mossamb. iv. p. 2 (1868) ; 



A. Dum. Hist. Poiss. ii. p. 469 (1870) ; Giinth. Cat. Fish. viii. p. 322 (1870) ; 



A. Schneid. Zool. Anz. 1886, p. 524 ; Bouleng. Poiss. Bass. Congo, p. 32 



(1901), and Fish. Nile, p. 19 (1907). 

 Protomelus, Hogg, Ann. & Mag. N. H. vii. 1841, p. 359. 

 Rhinocryptis, Peters, Mon. Berl. Ac. 1844, p. 414. 



Body subcylindrical, more or less elongate, with pointed tail, at the 

 end of which the elongate dorsal and anal fins meet. Limbs slender, 

 styliform ; a more or less developed dermal fringe, with very thin rays, 

 at least on the fore limb. Six branchial arches and five branchial clefts. 

 External gills often distinct, especially in the young. Scales small, thin. 

 Vent lateral. 



Tropical Africa. 



Synopsis of the Species. 



Length of head 3|-4£ times in distance from snout 



to vent ; dorsal originating nearer occiput than 



vent ; 40-50 scales in longitudinal series to 



above vent ; 34-36 pairs of ribs 1. annectens, Ow., p. 20. 



Length of head 3i to 5 times in distance from snout 



to vent ; dorsal fin originating at equal distance 



from occiput and vent, or nearer latter ; 55-70 



scales in longitudinal series to above vent ; 35- 



41 pairs of ribs 2. P. cethioiAcus, Heck., p. 21. 



Length of head 5 to 6 times in distance from snout 



to vent ; dorsal fin originating much nearer 



vent than occiput ; 86-91 scales in longitudinal 



series to above vent ; 54 pairs of ribs ... 3. P. dolloi, Blgr., p. 22. 



c2 



