SCIENTIFIC RESULTS FROM THE MAMMAL SURVEY, 431 
Type.—Adult male. Teeth worn. B. M. No. 21.12. 5. 84. Original num- 
ber 1999. 
Collected 9th June 1921 by H. W. Wells ; presented by the Bombay Natural 
History Society. 
Dimensions of the type, measured in the flesh ;— 
Head and body 290 mm., tail 335 mm., hindfoot 56 mm., ear 27 mm. 
Weight 1-25 lbs. 
Skull, greatest length 62 mm., condylo-incisive length 57:7 mm., zygoma- 
tic breadth 30 mm., nasals 247°3mm. ; interorbital breadth 8°S mm. ; 
breadth across postorbital projections 19°2 mm. ; zygomatic plate 5°6 mm.; 
palatilar length 29:3 mm. ; palatal foramina 12 x 5 mm.; upper molar 
series 13. 
This fine rat forms a second species of the genus Dacnomys, the discovery of 
which forms one of the most striking results of the Bombay Natural History 
Society’s Survey. The original species having been named in honour of 
Mr. Millard, I have thought it suitable that the second should bear the name 
of his friend and partner in the carrying out of the Bombay Survey, the late 
Mr. R. C. Wroughton, to whose memory I am proud to pay this last tribute. 
(B) THE PORCUPINE OF ASSAM. 
Among the Natural History Specimens obtained in Assam by Mr. J. P. Mills 
and presented by him to the Society there is a perfect and fully adult skull of a 
Porcupine, and I have been asked to determine its species. 
Tt is of medium size, and certainly does not belong on the one hand to a large 
Crested Porcupine, such as the ordinary Acanthion leucurus, nor on the other 
to the small crestless porcupine, A. hodgsoni. It would however appear to be 
related to the intermediate group of which A. brachyurus is the oldest known 
member, a group to which also A. klossi and suheristatus belong. This group 
ranges from China through Siam to the Malay Peninsula, but has not hitherto 
been found in Assam. 
The skull obtained by Mr. Mills would appear to represent a new species, which 
may be called— 
Acanthion millsi, sp. n. 
Size rather less than in A. klossi. General character of the skull more rounded 
and inflated than in £lossi, almost as much as in subcristatus, the upper outline 
strongly bowed. Region across forehead considerably swollen, so that the outer 
bar of the anteorbital foramen is scarcely visible from above, while itis broadly 
visible in klossi ; posterior part of interorbital region scarcely narrower than 
anterior. Nasals large, convex, much expanded behind, shorter but broader 
than those of klossi, and reaching well behind the lacrymal bones. Frontal 
suture comparatively long, just on half the length of the nasal suture, therefore 
longer proportionally than in the other species. Parietal region of skull rather 
short, not longer than the frontals, and with comparatively little occipital 
projection. Outer outline of zygomata more expanded at the level of the 
anteorbital bar, the two zygomata behind this bar more nearly parallel than 
in the allied species. Mesopterygoid opening broad. 
Dimensions :—Upper length 131 mm. ; condylo-incisive length 126 mm. ; 
zygomatic breadth 69 mm. ; nasals, length 69 mm., anterior breadth 25: 5mm., 
posterior breadth 39 mm.; breadth between outer corners of the anteorbital 
foramina 59 mm. ; interorbital breadth anteriorly 51 mm., posteriorly 
49 mm. ; median length of frontals 33 mm., of parietals 32 mm.; palatilar 
length 62 mm. ; breadth of mesopterygoid fossa 17 mm.; upper cheek-tooth 
series (crowns) 29. 
Hab.—Naga Hills, Assam ; type from Sangrachu, 3,500’. 
