426 Bulletin American Museutn of Natural History. [Vol. XIX, 



Osmeroides ornatus, sp. nov. 



Plate XXXIII, Figure 5. 



No. 4518 (3870), from Hakel, appears to belong to an un- 

 described species of Osmeroides. Only a single specimen has 

 been found in the collection. The total length is 48 mm.; 

 to the base of the caudal 36 mm. The length of the head, 

 including the opercular apparatus, equals 14 mm. The 

 greatest depth is 12.5 mm. It will be seen, therefore, that 

 the depth'is less than the length of the head, and is contained 

 in the distance from the pectoral arch to the base of the 

 caudal fin less than twice. There are 25 vertebrae behind the 

 operculum; hence not more than 30 altogether. There are 

 II or 12 in the caudal region. The dorsal fin arises 7.5 mm. 

 behind the occiput. The number of its rays is uncertain, but 

 there are probably not more than 10. The ventrals are in- 

 serted below the anterior half of the dorsal. The rays of the 

 anal cannot be counted, but the fin is short. The caudal is 

 deeply forked. The pectoral fins are delicate and inserted 

 well above the ventral border. 



The scales are thick and deeply serrated, as may be seen 

 on the matrix, and even in some places where the scales over- 

 lie one another. The operculum is conspicuously ornamented 

 with coarse ridges and rows of tubercles, which radiate from 

 the articulation of the bone with the hyomandibular. There 

 seem to be similar ridges on the other opercular bones and 

 apparently on the cheeks. 



The mouth appears to have been relatively small, the ar- 

 ticulation of the lower jaw being advanced to a perpendicular 

 line from the front of the orbit. The lower jaw is only 5 mm. 

 long. The orbit is rather large. 



This species differs from 0. megapterus, a Sahel Alma 

 species, in having fewer vertebrae, 30 or fewer instead of 40. 

 From 0. woodwardi Hay (= 5. attenuatus A. S. Woodward), 

 from Hakel, it differs in being less elongated and in having 

 coarsely serrated scales. It appears to resemble most 0. 

 pusillus, described as Sardinioides pusillus by Dr. Woodward, 

 from Sahel Alma, but the latter is a more robust species, with 



