1. MtroiL. 413 



rate length ; the abdominal vertebrae have strong and broad parapo- 

 jAyses, from which the slender ribs are suspended. The neural spines 

 of the first seven vertebra; are short, and dilated into more or less 

 confluent lamella; ; the first interneural is spatulate, with a ridge on 

 each side, and attached to the seventh vertebra. The other neural 

 and haemal-spines are slender and rather short ; two or three inter- 

 neiirals of the second dorsal and two or three interhaemals correspond 

 to one neural or haemal ; the first two intemeurals of the second 

 dorsal fin are behind the apophysis of the thirteenth vertebra. 



lines. 



Length of the first vertebra 4 



of the sixth and twelfth vertebrae .... 5 



of the twenty -thii'd vertebra Sg 



; of the abdominal portion 5G 



of the caudal portion 69 



Synopsis of the Species. 



I. Orbit with the adipose eyelid well developed, covering at least a third 

 of the iris postenorly. Upper lip not very thick. 



A. Anal fin with eight soft rays. 



a. L. lat. 40-45. 



a. The maxillary is entirely hidden, or only a narrow lateral stripe 

 of it is visible. 



• Mandibulary angle obtuse ; pectoral above the middle of the 



body 1. M. cephalus. 



• Mandibulary angle obtuse ; pectoral on the middle of the 



body 2. M. lineatus. 



• The mandibulary angle is a right one ; the height of the body 



is one-fourth of the total length. 3. M. constantia;. 



• The mandibulaiy angle is a right one ; the heiglit of the 



body is one-fifth of the total length ; the anterior dorsal 

 spine is on the middle, between snout and base of the cau- 

 dal fin 4. M. cephalotus. 



• The mandibulary angle is a right one ; the height of the body 



is one-fifth of the total length ; the anterior dorsal spine i!» 

 nearer to the snout than to the base of the tail. 



5. M. rammelsbergii. 



• The mandibulary angle is acute . 6. M. dobula. 



/3. The extremity of the maxillary is not hidden by the prajor- 

 bital 7. M. haeraatochilus. 



(y. The upper lip is obliquely truncated below the snout. 



8. M. pcrusii.) 



b. L. lat. 32-35 9. M. liza. 



e. L, lat. 30 10. M. subviridifl. 



