Mr. J. Gould on four new species of Mus. 229 



whole length of the fish, and above it a stripe of equal breadth of a 

 brownish-purple colour. This stripe reaches the tip of the caudal 

 in one direction, and in the other passes over the upper part of the 

 gill-cover, along the sides of the head to the mouth. Above, the 

 back is of a lighter brown, and along the base of the caudal there 

 is a purplish-black line. These colours are described as they exist 

 after two or three years of maceration in spirits, and they have doubt- 

 less undergone alteration since the fish was taken. 



Science is indebted for this novel and highly interesting form of 

 fish to the late Captain Sir Everard Home, who never lost an oppor- 

 tunity of adding to our natural-history collections. He obtained it 

 in King George's Sound. Some half-digested pieces of fish were 

 found in the mouth, but nothing except mucus in the intestines. 



Dimensions. 



Length from tip of the snout to extremity of caudal, Inches. 



exclusive of rostral barbel 1 6*50 



from tip of the snout to tip of the gill-cover. . 4*80 



from tip of the snout to fore-edge of the orbit 3*00 



from tip of the snout to anus 10*00 



Distance between the orbits 0*38 



Length of diameter of the eye 0'45 



of rostral barbel 0'62 



from posterior angle of the eye to the tip of 



the gill-cover 1 -43 



of the opening of the mouth ] • 10 



Height of the head behind the preoperculum 0*65 



Greatest breadth of shoulders or nape 0'70 



Height of body behind the pectorals I -00 



Length of naked space between dorsal and caudal . . 2*00 



of caudal fin 2'50 



of attachment of anal fin 1 '80 



of pectorals O'Oo 



Height of posterior dorsal rays , . 0*80 



November 24, 1857.— J. Gould, Esq., F.R.S., V.P., in the Chair. 



On Four New^ Species of Mus and one of Hapalotis 

 FROM Australia. By John Gould, F.R.S., V.P., etc. 



Mr. Gould alluded to the prevailing opinion that none but Mar- 

 supial animals were to be found in Australia, and observed that this 

 opinion may be correct to a certain extent, yet the Placentalia are 

 well represented in that country by numerous species of the genera 

 Hapalotis, Mus, &c. ; and remarked that in few countries are the 

 smaller members of the Rodentiamore abundant both in species and 

 individuals. It is to this latter order that the four new species now 

 exhibited by him pertain. 



For the first of these he proposed the name of 3Ius assimilis ; this 

 animal is about the same size as the Mus decumanus of Europe, and 



