200 Mr. O. Thomas on small Mammals 
In addition, his material of the short-tailed mole-like 
burrowing rats has greatly advanced our knowledge of these 
interesting and little-known animals, which now prove to 
belong to two distinct genera, of which, again, one needs 
description as new. 
Our thanks are due to the kind friends who gave Sr. Budin 
help and hospitality, and to Sr. Budin himself for the keen 
and successful manner in which he has carried out the mission 
entrusied to him. 
1. Lasiurus borealis, Mull. 
9. 60,66. Beatriz, Nahuel Huapi. 800 m. 
2. Oryzomys magellanicus mizurus, Thos. 
by. 195,197,200, 212.2155 9... 1T 101 192 eo oe 
199, 220. Maiten, Upper Chubut R. 700 m. 
(?) o. 58, 102,105, 113, 118, 119. | Beatuzy Nalnel 
Huapi. 800 m. 
‘The most common species at Maiten. Called ‘ Coludo.’” 
—E. B. 
3. Reithrodon cuniculoides, Waterh. 
9.173. Maiten. 700 m. 
Being a single specimen only I am not able to satisfy 
myself as to what subspecies of A. cunteulotdes this should 
be referred to. All the forms that have been named in this 
difficult group are distinguished by somewhat intangible and 
more or less variable characters. 
4, Phyllotis zanthopygus, Waterh. 
dS. 128, 129, 132, 133, 134, 136, 147, 148, 151, 153; 
@. 130, 131, 137, 138, 140, 146, 149. Pilcafieu. 1400 m. 
In these specimens the buffy wash on the under surface is 
far more marked than would be supposed from either Water- 
house’s or Allen’s description. But the type—no. 55.12.24.185 
—shows clearly the same general buffy tone to the hairs of 
the belly, none of them being really tipped with white. 
“ Caught among the cactus-plants.’”— LH. B. 
5. Irenomys longicaudatus, Phil. 
d-(imm.). 73. Beatriz, Nahuel Huapi. 800 m. 
Lhis most interesting specimen represents the re-discovery 
of Philippi’s Rethrodon longicaudatus, whose identity has 
ong been a mystery. It proves, as might be expected, to 
belong to an undescribed genus, which may be called 
