S28 



pointed teeth. The mandibulary lamina is large, and forms a 

 transverse crescent ridge, like the teeth of a Scarus, and show- 

 ing at its edge faint traces of teeth. I believe it is not 

 externally visible in the living specimens. Suctorial teeth in 

 numerous transverse series, those situated backwards larger than 

 the others ; lingual teeth, two in number, straight, strong, and 

 conical. Seven branchial openings, large, round, and bordered. 

 The distance between the two dorsals and the base of the caudal 

 is a little more than the diameter of the mouth, and this is equal 

 to half the distance from the end of the snout to the anterior 

 edge of the eye. The caudal fin is discoid, and rounded at its 

 extremity. 



The colour is of a dark blue on the back, and silvery on the 

 sides and belly ; on the middle of the back, a little before the 

 insertion of the first dorsal, begins a space of a brilliant green, 

 which extends to the tail ; fins red, bordered with black. 



Found in the Saltwater Eiver. The following are its dimen- 

 sions : — 



Inches. 



Total length 20^ 



Circumference of the middle of body 2f 



From muzzle to centre of eye ].-§■ 



to first branchiostegal opening If 



to last 3-g- 



— to beginning of first dorsal 12f- 



Length of first dorsal - If 



From first dorsal to beginning of second If 



Length of second dorsal 1J- 



From second dorsal to beginning of caudal f- 



From beginning of caudal to end of body 1| 



From end of body to anus 5f 



A very young individual, only three inches long, has exactly the 

 same form, the same dimensions, and the same dentition. 



Mr. F. Gr. Waterhouse has kindly sent me, from the Torrens 

 Eiver, Adelaide, a specimen of the only sort said to inhabit those 

 waters, and which I felt a great desire to examine, as the typical 

 specimen of Geotria was said to have come from that Colony. This 

 specimen is exactly like the one from the Saltwater Eiver, only 

 ome of the suctatorial teeth are long and sharp, and this is caused 



