514 DR. A. GtJNTHEH ON A ZOOLOGICAL [Juiie 23, 



19*5, greatest breadth 5*7; iiiterorbital constriction, least breadth 

 7-0; interparietal, length 6-6, breadth 11-5: length of base of 

 anterior zygoma-root G-0 ; palate, length 30'0, breadth outside m' 

 10-3, inside 4-4 ; palatal foramina, length 10-1 ; back of incisors to 

 m' (alveoli) 15'7; upper molar series 90. 



This fine new Rat belongs to a small group of species inhabiting the 

 East-Indian Archipelago, all of which agree with Mus macleari in 

 being of large size, with very long tails tipped with yellow, and with 

 small rounded ears. Their differential characters as compared to 

 M. macleari are best put in tabular form : — 



M. macleari. Mammee 1 — 1 = 4. Dorsal piles present. Front 

 edge of anterior zygoma-root projecting, very convex. Pa- 

 latal foramina long. Bulloe very small. 

 Christmas Island. 

 M. celebensis, Gray\ Mammae 1 — 2 = 6. No dorsal piles. 

 Front edge of anterior zygoma-root not projecting, Palatal 

 foramina short. 

 Celebes. 

 M. xanthurus, Gray^ Mammae 1 — 2 = 6. Long dorsal piles 

 present. Front of zygoma-root but little projecting. Palatal 

 ibramina long. 

 Celebes. 

 M. everetti, Giinth.^ Fur long, but the piles not enormously 

 lengthened. Front of zygoma-root convex. Palatal foramina 

 long. Bullae very large. 

 Philippines. 

 M. meyeri, Jent.'* Fur without lengthened piles. Supraorbital 

 edges much developed. Front of zygoma-root slightly convex. 

 Palatal foramina short. Teeth very large. 

 Celebes. 

 M. muelleri, Jent.' Mammae 2 — 2=8. No dorsal piles. Tail 

 unicolor. Front edge of zygoma convex. Palatal foramina 

 short. Teeth rather small. BuUce medium. 

 Sumatra and Borneo. 



This last does not properly belong to the present group of species, 

 but is only introduced to complete the list of those of which it is 

 necessary to mention the distinguishing characters when describing 

 M. macleari as new. All these species also differ from M. macleari 

 in having the general colour grey or yellow instead of rufous. No 

 other described species could possibly be confounded with the present 

 most interesting new form, with which I have much pleasure in 

 connecting the name of Capt. Maclear, of H.M.S. ' Flying-Fish,' to 

 ■whom the Museum is indebted for the Christmas-Island specimens. 



1 P. Z.S. 1867, p. 598. = Loc. cit. 



3 P. Z. S. 1879, p. 75. ' Notes Leyd. Mus. i. p. 12 (1878). 



'' Oji.cit ii. p. It) (1879). 



