298 Mr. O. Thomas on the Echimyine. 
developed ; brown above, whitish below ; scales about ten to 
the centimetre. 
Skull about as in NV. dasythrix, the palatal notch perhaps 
deeper and sharper. Relation of back of nasals to end of 
premaxillary processes very variable. 
Dimensions in the flesh :— 
Head and body 220 mm.; tail 212; hind foot 33; 
ear 14. - 
Skull: greatest length 51; condylo-incisive length 45 ; 
zygomatic breadth 24; nasals 15°2 x 5; interorbital breadth 11; 
palatilar length 19; upper tooth-series 11-2. 
Hab. Lamareé, Bahia, about 70 miles N.W. of Bahia city. 
Alt. 300 mm. 
Type. Adult female. B.M. no. 3.9. 5.96. Original 
number 1414. Collected 24th May, 1903, by Alphonse 
Robert. Presented by Oldfield Thomas. Thirteen specimens. 
This species is readily distinguishable from any other we 
have by its pale colour and less bushy tail. It had been 
provisionally determined as dide/phoides, Desm., but there is 
really nothing to connect it with that species, which had no 
locality, is far smaller, and was stated to be of a brown 
colour, which no one would say of the present animal. 
Indeed, there is no evidence that didelphoides even belonged 
to the restricted genus Velomys. 
Of the original Echimys hispidus, ‘ Geoff.,” apparently 
first validly published by Desmarest in 1817, I have, by the 
kindness of Dr. Anthony, been privileged to examine the 
typical skull, still preserved in the Paris Museum. This 
shows that 1. Aispidus, about which so much confusion has 
arisen from time to time, belongs to none of the genera to 
which it has been hitherto referred, but is a Mesomys, appa- 
rently quite similar to J/. ecaudatus, Wagn. As a result, 
the early and suitable name Aispidus will happily replace 
the unfortunate term ecaudatus, given to a specimen which 
had lost its tail. Some notes on the characters of this rare 
genus were published in 1905 *. 
DacTYLomys. 
A comparison of our specimens of Dactylomys dactylinus, 
Geoff., and D. peruanus, Allen, indicate that they might very 
well represent distinct subgenera. LD. dactylinus has its long 
tail practically naked (apart from the base), the few fine hairs 
on it not at all hiding the scales, which are large and con- 
spicuous. Indeed, it is the most prominently naked tail in 
the family, almost rivalling that of Uromys in this respect. 
* Ann, & Mag. Nat. Hist. (7) xv. p. 590. 
