PETERSIUS. 231 



6. PETERSIUS. 

 Hilgend. Sitzb. Ges. naturf. Fr. Bcrl. 1894, p. 172 ; Bouleug. Poiss. Bass. Congo, 

 p. 165 (1901). 



Characters of Micralest.es, but distinguished by the absence of the 

 pair of conical teeth behind the mandibular series. Vertebrae 3G-37 *. 

 Tropical Africa. 



Synopsis of the Species. 



I. Anterior praemaxillary teeth alternating with the posterior. 



A. D. 10-11 ; A. 19-26. 



1. Sc. 33-40 jjfcfi. 



O.J— 4^ 



a. A. 23-26 ; depth of body 3-31 times in total length. 



QI 



Sc. 40 jjf ; lower jaw projecting beyond upper . 1. P. modest us, Blgr., p. 232. 

 Sc. 35-36 gj ; lower jaw not projecting beyond 



upper 2. P. kiljeadorfi, Blgr., p. 232. 



b. A. 19-22. 



7— 

 Sc. 3o3| ; diameter of eye 3^ times in length of 



head; depth of body 2f times in total length. 3. P. conserialis, Hilg., p. 233. 



Sc. 35-36 t£ ; diameter of eye 2|-2f times in 



length of head ; depth of body 3f — 4 times 



in total length 4. P. tangeusis, Lonnb., p. 234. 



2. Sc. 28-31 g ; A. 22-24. 



Depth of body 3i-3f times in total length ; 



teeth with very long median cusp . . . 5. P. leopoldianas, Blgr., p. 235. 



Depth of body 3 times in total length . . . . 6. P. brumpti, Pellegr., p. 235. 



Depth of body 2^-2^ times in total length . . 7. P. caudalis, Blgr., p. 236. 



3. Sc. 24-26 ,tj ; lateral line incomplete. 



A. 20 ; depth of body 2§-2f times in total length. 8. P. pulcher, Blgr., p. 237. 

 A. 21-22 ; depth of body 24^-24, times in total 



length 9. P. major, Blgr., p. 237. 



B. D. 12 ; A. 14 ; Sc. 28-30 |f . . . . 10. P. spilopterus, Blgr., p. 239, 



II. Anterior praemaxillary teeth corresponding to the posterior. 

 31 



Sc. 29-30 ^|; A. 20-21 ; depth of body 4 times 



in total length 11. P. woosnami, Blgr., p. 239. 



Sc. 24-27 || ; A. 21-24 ; depth of body 3-34 



times in total length 12. P. ocMentalis, Gtbr., p. 240. 



* The type of the genus, P. conserialis, differs from all its congeners by its large size as 

 well as by the complete closing up of the parietal fontanelle. 



