6 Records of the Indian Museum. [Vol. XIII. 



find that there is not the difference in size at present beUeved, 

 The skulls of both are of the same elongate form, only slightly 

 curved above from front to back/ but the bullae of bowersi are 

 considerably larger and more dilated than those of fcrreocamts : 

 on the other hand the molars are smaller (both shorter and 

 narrower), the alveolar lengths of the upper tooth-rows being 

 respectively 87 and 9-4 in skulls of equal length. In the type of 

 bowersi the incisors are light orange-yellow ; in ferreocanus they 

 are ivor^ with pure white tips. The latter, though a member of 

 the bowersi group and representing it in the Malay Peninsula, 

 appears to be a well-marked and distinct species. 



Some measurements of the tj^pe skull of bowersi are : — greatest 

 length, 54'o; condylo-basilar length, 47'8; basilar length, 447; 

 palatilar length, 252 ; length of palatal foramina, 9-0; diastema, 

 17*0; upper tooth-row (alveolus), 87- nasals, 207 X5"3 ; inter- 

 orbital breadth, 8*0; greatest cranial breadth, 21*3. 



2. Rattus berdmorei (Blyth). 



M/is bt'i'dfiiorci, Blyth, 'Joi/ri/. Asiaf. Soc. BeiiguL XX, p. 173 118511: 

 id., op. cit., XXIII, p. 343 (1863); Sclater. P.Z.S., i8<)o. p. 524; 

 iiL, Cat. Mamm. hid. Miis., II, p. 71 (^1891 ). 



Epimys berdmorei. Thomas, 'Joan/. Boii?btn' .Vaf. Hist. Soc. XX I \', \). 

 413 (1916). 



All that remains of the type of this species, which was obtained 

 by Berdmore at Mergui. Tenasserim (and which is still unique), is 

 a portion of the skull including the zygomata to their posterior 

 roots and possessing above the greater part of the parictals, but 

 lacking below the bullae and basioccipital, etc. 



I am glad to find that Thomas [l.c.s.) shares my opinion that 

 this species possesses the same large bullae as my R. b. magnus of 

 South-Eastern Siam (P.Z.5., 1916, pp. 57-61, text-figure r, w-here 

 details and measurements of the skull of berdmorei are also given). 

 The mandible has disappeared but the upper incisors are of 

 similar colour to those of bowersi and show the same lack of 

 curvature. 



3. Rattus rattus robustulus (Blyth). 



Mils robasfuliis, Blyth, 'Joiirn. Asiat. Soc. Bengal. XXVIII, p. 't)4 



(1859) : id., op. cit., XXXII, p 343 (1863). 

 Mns rattus var. D. nifescens, Sclater, Cat. Mannii. hid. Miis.. II, p. 



66 (1891). 



The type of this form, an adult male with slightly worn teeth 

 obtained by Berdmore at Schwegyin, Tenasserim, is a spirit speci- 

 men with a practically perfect skull. 



It shows the following external dimensions :— head and body, 

 163 (approx.); tail 153 (possibly slightly imperfect): hind-foot, 

 33'5; ear, 19-5. 



1 Sclater's figure is excellent; Miller's {loc. cit.. fig. 4) I regard as less satis- 

 factory. 



