AUSTRALIAN GOIUID^ McCULLOCU AND OGILBY. 245 



A series of thirty-six speciineiis, 52-113 mm. long, including Mac. 

 leay's types, indicates tliat G. semifreuatus may be distinguished from 0. 

 hifrendtns by certain differences in the colour-marking. O. hifrenatns has 

 well defined bridle-marks, and the upper surface of the head without 

 spots; body without cross-bars; dorsal fins longitudinally banded, and 

 the caudal with broad bars. In G. semifrenatus the bridle-marks are less 

 definite, and the head is distinctly spotted above; body with cross-bars; 

 dorsal fins with oblique rows of grey spots, and the caudal with small 

 interradial spots. The two species are very similar in structure, differ- 

 ing only in the form of the caudal fin, and in the disposition of the 

 anterior scales. They have been captured together in a prawn-net at Sans 

 Souci, Botany Bay, by Mr. J. H. Wright, but as the two forms of colour- 

 marking do not appear to be correlated with either growth or sex, we 

 regard them as representing distinct species. 



Locs. — Specimens are in the Australian Museum from Port Jackson 

 and Botany Bay, New South Wales. 



Hah. — New South Wales. 



Genus Rhinogobids, Gill. 



Bhinogobiitt!, Gill, Proc. Acad. Nat. Sci. Philad., 1859, p. 145 (B. similis, 

 Gill). 



Body robust, compressed, covered with large ctenoid scales, which 

 become cycloid on the breast and the base of the pectoral. Head entirely 

 naked, with lines of mucigerous pores crossing the cheeks and opercles, 

 and large open pores above the nostrils, on the interorbital space, along 

 the nuchal groove, and around the preopercular margin. Snout obtuse, 

 the profile convex. Jaws subeqnal. Mouth a little oblique ; no barbies. 

 A band of villiform teeth in each jaw, and an outer series of enlarged 

 ones ; a subcaniniform tooth may be present on each side of the mandible. 

 Tongue subtruncate, and free anteriorly. Gill-openings lateral, the 

 isthmus broad. Exposed edge of the shoulder-girdle smooth. Pseudo- 

 branchiae present. Gill-rakers short and thick, about five on the lower 

 limb of the first arch. Dorsal fins short, with about six spines and ten 

 rays ; anal similar to the soft dorsal. Pectorals rounded, without free 

 rays. Ventrals large, united, with a broad basal membrane ; they have 

 one spine and five rays. Caudal rounded. 



The above definition is based upon B. nebalosus, Forskal, and B. 

 lefhvitchi, Ogilby. 



Key to the Australian species. 



a. Eye larger ; three large dark lateral blotches, scales without dark borders 



nebidosiis. 

 aa. Eye smaller ; five smaller lateral blotches, scales with dark borders leftwitchi. 



Rhinogobids nebdlosus, Forskal. 



Gobius nebulosus, Forskal, Descr. Anim., 1775, p. 24. Id., Bloch and 

 Schneider, Syst. Ichth., 1801, p. 72. Id., Cuvier and Valenciennes, 

 Hist. Nat. Poiss., xii., 1837, p. 84. 



