J^iO PRISTIPOMATrC^. 



1 . Gerres plumieri. 



Chv. ^- Val vi, p. 452. pi. 167. 



D. A. A. ^g. L. lat. 37. L. transv. 6/11. Vert. 10/14. 



The height of the body is 24- in the total length (without caudal 

 fin). Praeorbital serrated; the second dorsal and anal spines ex- 

 ceedingly strong and long ; the former slightly longer, nearly as long 

 as the head. Silvery, with more or less distinct longitudinal stripes 

 corresponding to the series of scales ; dorsal generally blackish. 



Atlantic coasts of Tropical America. 



a. Fine specimen. S. Domingo. Purchased of Mr. Cuming. 

 h. Skeleton. S. Domingo. Purchased of Mr. Cuming. 



c. Fine specimen. Central America. From M. Salle's Collection. 



d. Adult. Guatemala. Piuxhased of Mr. Frank. 



e. Adult. Pemambuco. Presented by J. P. G. Smith, Esq. 



f. Adult. Bahia. Piu'chased of M. Parzudaki. 



f/, /(. Half-grown and young : skins. South America. From Dr. 

 Pamell's Collection. 



Air-bladder simple. 



Skeleton. — The skuU of Gerres exhibits several peculiarities by 

 which it may be distinguished from any other : they are — the high, 

 triangular occipital crest, with a deep groove in front, to receive two 

 very elongate processes of the intermaxillary bones, the peculiar 

 shape of the jaws, and the broad and strong pubic bones. The max- 

 iUaiy bone has a somewhat irregiilar form, is slightly curved, and 

 has a broad shallow groove along its upper and posterior margin. 

 The front part of the intermaxillaiy bones is broad and slightly 

 excavated, not imlike the upper jaw of some Tortoises ; the pos- 

 terior processes are very slender, flexible, and extend backwards into 

 a groove of the occipital crest situated on the posterior half of the 

 frontal bones ; the descending branch of the intermaxillary also is 

 rather irregularly formed and bent. The mandibula has the inferior 

 margin slightly concave ; the front part of the dentary is rather flat 

 and horizontal, whilst the posterior part, together with the adjacent 

 portion of the articulary, forais a high and elevated ridge. The tur- 

 binal bones are very elongate, irregularly bent, and transformed into' 

 a half- channel. The praeorbital is triangular, broadest anteriorly, 

 and with the inferior margin distinctly serrated; the infraorbital 

 arch, like the posterior part of the praeorbital, is narrow, and without an 

 interior plate. The head of the vomer forms an angidar prominence, 

 but without any teeth : the palatine bones are deeply grooved. The 

 posterior margin of the pra^operculiun is nearly straight and minutely 

 serrated ; the angle is roimded, and armed with equal and coarse 

 denticulations ; the lower margin is straight and very distinctly ser- 

 rated. The operctilum is twice as deep as long, five-sided, with the 

 posterior side slightly emarginate, and \vithout prominent points ; its 

 inferior angle is very acute. The sub- and interoperculum are very 

 thin ; their inferior margins ai'e entire, and form together a very 



