462 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 
Subfamily IV.—HAXMULIN. 
XII. HAMULON. 
Diabasis * Desmarest, Premitre Décade Ichthyologique, 1823, 34 (parra; flavolineatus; 
not of Hoffmannsegg, Coleoptera, 1819). 
Heemulon Cuvier, Regne Animal, ed. 2, 1829 (elegans, etc.). 
Orthosteechus Gill, Proc. Acad. Nat. Sei. Phila. 1862, 255 (maculicauda). 
Hemylum (Scudder mss.) Putnam, Bull. M. C. Z., 1863, 12 (elegans, etc.). 
Diabasis (Scudder mss.) Putnam, 1. c. (album; name only). 
Anarmostus (Scudder Mss.) Putnam, l. c. (name only; jflavolineatum, etc.). 
Bathystoma (Scudder Mss.) Putnam, |. c. (name only; jeniguano, etc.). 
Brachygenys (Scudder Mss.) Poey, Synopsis Piscium Cubensium, 1868, 319 (name 
only; teniatum). 
Lythrulon Jordan & Swain, Proc. U.S. N. M. 1884, 287 (flavoguttatum). 
Heemulon Cuv. & Val., Giinther, Gill, Poey, Goode, ete. 
Diabasis Bennett, Bleeker et auct. 
Type: Hemulon elegans Cuvier=Sparus sciurus Shaw. 
Etymology: aia, blood; odijov, the singular of odja, the gums. 
All the species of Hamulon are American. The genus is very closely 
related to Pomadasis Lacépede (=Pristipoma Cuv.), the only tangible 
points of difference being the large mouth with curved gape and the 
closely scaled soft dorsal and anal fins. AJIl the species have more or 
less of orange on the inside of the mouth, a trait of coloration not found 
in Pomadasis. The amount of redness is greatest in those species hav- 
ing the largest mouth. It is true that certain species of Pomadasis 
(humilis, etc.) have the mouth larger than in certain species of Hamu- 
lon (chrysargyreum). It is also true that while the soft dorsal and anal 
in many of the species referred to Pomadasis are free from scales, in 
certain of the subgenera or genera related to the latter genus (Brachy- 
deuterus, Anisotremus) these fins are hardly less scaly than in Hamulon. 
It is probably also true that certain species of Hamulon (chrysargyreum) 
are more closely related to species of the section Brachydeuterus 
(axillaris, nitidus, leuciscus) than this section is to some other spe- 
cies usually placed in the same genus. There is no doubt, however, 
that the species of Haemulon form a natural group, and no writer since 
Desmarest and Cuvier has questioned the right of this group to generic 
rank. It has been generally conceded that the group will not admit 
of further subdivision. The most aberrant of the species (maculicauda) 
yas, In 1862, recognized by Dr. Gill as the type of a distinct genus, 
Orthostechus, distinguished by the arrangement of its scales. In 1862 
these fishes were the subject of an elaborate study by Mr. Samuel H. 
Scudder. Nothing has, however, been published by this writer, our 
* Le poisson que je viens de décrire me parait, selon les principes de classification 
ichthyologique de M. Cuvier, devoir former un genre A part. Je lui donne le nom 
de Diabasis, AraBaow (transitio), pour indiquer ses rapports, d’une part, avec les 
Acanthopterygiens des genres Lutjan et Pristipome, et de autre avee les poissons 
placés dans la famille des Squamipennes. (Desmarest. ) 
