266 PROCEEDINGS OF THE ACADEMY OF 



like the preoperculum and operculum ; snout oblique. Eyes large, longitudi- 

 nal elliptical, oblique, and closely approximated, situated chiefly or entirely 

 in the anterior half of the head. Opercula unarmed ; operculum well de- 

 veloped, as long as or longer than the region between it and the eye. 



Mouth with the cleft oblique, longitudinal, the periphery of each jaw ovoid, 

 the supramaxillars ending beneath the pupils. Lower jaw even or slightly 

 projecting beyond the upper. Intermaxillars slightly protractile downwards, 

 with the posterior processes short and wide, rounded at their ends; with the 

 lateral branches thick and attenuated towards the ends, but with a thin 

 crescentiform crest above, along the posterior half. Supramaxillars neariy 

 twice as long as the intermaxillars, with a compound apophysis in front; 

 thence nearly rectilinear, compressed, highest at the middle, again slightly en- 

 larged and convex at the ends. 



Tongue thick, emarginated in front, and tree. 



Teeth conic, curved, pluriserial ; those of the upper jaw enlarged in the 

 outer row. Palate smooth ; vomer projecting. 



Branchial apertures lateral, nearly vertical, bounded above by a membrane 

 attached near the axil of the pectoral fin ; below, continued forwards in a 

 short slit between the fourth ray and the breast. 



Branchiostegal rays five. 



Anal papilla small. 



Dorsal fins considerably separated ; the first considerably behind the ven- 

 trals, oblong, convex at the middle, and with seven slender spines, between 

 the last of which and the penultimate a wider interval exists. Second dorsal 

 rather long (I. 19 pm.), with most of its rays with the anterior branch single 

 and the posterior bifurcated. Last ray free behind. 



Anal fin shorter than the dorsal (I. 16 pm.), but coterminal behind with it. 

 and of similar structure. 



Caudal fin well developed, convex behind, and with numerous supplement- 

 ary rays above and below its peduncle. 



Pectoral wide, produced and rounded behind, with the base little oblique, 

 but extending nearly to the plane of the chest, with its superior as well as the 

 other rays well defined and branched. 



Ventral fins considerably behind the pectoral, very obliquely infundibuli- 

 form, the inner rays longest and well connected ; the interspinous membrane 

 low. 



The genus Lepidogobius is readily distinguished by its elongated body, small 

 cycloid scales, form of head, development of the fins, and especially by the 

 posterior insertion of the ventral fins. A single species has been discovered ; 

 the Gobius Neivberrii, formerly referred to it wnen known only through the de- 

 scription of Girard and the comparison instituted between it and L. gracilis, 

 belonging to a distinct genus. The type of Lepidogobius has been placed by Dr. 

 Giinther in a section of Gobius characterized by having " the anterior dorsal 

 with seven to nine spines." In this section, besides Lepidogobius, species ot 

 the genera Eucyclogobius, Acantho gobius, (nearly allied to Au-aous, but having 

 an increased number of spines and a scaly head), Chselurichthys R., and two 

 Japanese genera have been placed. One of the latter genera, typified by 

 Gobius virgo T.S., is distinguished by the long dorsal and anal fins (VIII. I. 

 25 27. A.I. 26.), very small scales, and the form of the head ; it may be 

 called Pterogobius. Another resembles Gobionellus Gd., but is distinguished 

 by the increased dorsal and anal fins (D. VIII. IX. 20. A. 17.), &c. It is 

 represented by Gobius hasta, which may be called Synechogobius hasta. 



Lepidogobius gracilis Gill. 

 Synonymy. 



Gobius gracilis Girard, Proc. Academy of Natural Sciences of Phila.. vol. vii. 

 p. 134, 1854. 



[Sept. 



