634 PROCEEDINGS OF THE NATIONAL MUSEUM. vou. xxxtv. 
PETAURISTA BATUANA Miller. 
1889. Pteromys nitidus, JENTINK, Notes Leyden Museum, XI, p. 26. 
1908. Petaurista batuana MILLER, Smithsonian Miscell. Coll., XLV, p. 27, 
; November 6, 1908. 
1905. Pteromys nitidus, SCHNEIDER, Zool. Jahrb. Syst., XXIII, p. 104. 
1908. Petaurista nitida marchio THomas, Ann. Mag, Nat. Hist., 8th ser., I, 
March, 1908, p. 251. | 
Ten specimens, skins and skulls, from various places on the east 
coast of Sumatra. For a list of localities and measurements see table 
below. I can find no essential differences between the series from 
Sumatra and that from the Batu Islands off the west coast of Suma- 
tra. The extremes of total length of skull in Sumatran examples are: 
65 to 68.4 mm., in the Batu series 65.8 to 69.4; the extremes of the 
maxillary tooth row are, respectively, 14.6 to 16 and 15.5 to 16.8. The 
teeth in the Batu specimens thus appear a little larger than they 
do in Sumatran examples and as a whole look heavier. This may 
probably be accounted for by wear, as in nearly all the Batu skulls 
the crowns of teeth are worn to a flat surface, while the teeth in most 
of the Sumatran skulls have the primary cusps unworn. As the cusps 
become worn down the teeth assume a somewhat heavier appearance. 
PETAURISTA NITIDULA Thomas. 
1900. Petaurista nitidula Tuomas, Novitates Zoologice, VII, p. 592, 
December 8, 1900. 
_ Four skins and skulls from Pulo Rupat. They are distinctly 
smaller than the related flying-squirrel from Sumatra and so closely 
Measurements of flying squirrels from Sumatra. 
| 3 Sl |S sl | f 
| Si Slee | Sie 
| ee ol |e ie 
io} H 5 So 5 ma 
Name Locality Num- Sex and age KS) S iS z i= 2 pe 
“a | ste NS ber. eae. Ble |Se a = : ate) 
| _ os} © 
| ios} om q oO tet) a 
vo @ [pS = s S 
oh et fol 1S | Se IS 
Sciuroptcrushageni) Aru Bay..........-.. 143344 | Male, adult..-...| 270 | 248 | 49 |......|......]..... 
DOS eee tees oe CMscade Se Aaa hae 143345 ema, nearly | 254 | 240 |} 48 | 51.1 | 31.3 |_.... 
; adult. 
Petaurista nitidula.| Pulo Rupat.......... 143339 | Male, adult.....| 405°] 460 | 77 | 63.9 | 43 15.3 
iD) Oe eee eee ee eee COE een ee ies 143340 | Female, adult.-..| 380 | 440 | 75 | 62.6 | 44.3 | 15.2 
IDOE or ea ee Ae Osea eee ae 143341 |..... CORR cee 400 ‘| 405 | 75 | 64.3 | 42.8 | 15 
Docks hil eelaaee CLO Eee oe a 1433425 eee O22 eee 395 | 425 | 77 | 65 45.4 | 14.5 
Petaurista batuana.| Aru Bay........--..- 143338 | Male, adult ..... 430 ! 470 | 85 ! 68.4 | 46.4 ! 16 
DOR ate ee stemilgs up Little Siak | 144211 |..... GORA ee 385 | 485 | 81 | 65 44.8 | 15 
lver. | 
DOF eee Siak River near | 144212 | Female, adult..-.| 415 | 465 | 82 | 66.2 | 45 15.8 
mouth. | 
i) Oats ee arte | ee OR ae eee 144213 |....- COMER eat 420 | 465 | 82 | 67.3 | 44.6 | 15.8 
DOs eee eae Sungei Mandau......- 144214 | Male, adult..... 405 | 500 | 84 | 67.2 | 46.3 | 15.3 
Does he sees Kompelcs sees 144215 |....- dosemeter 392 | 483 | 80 | 65 | 43.5 | 15 
ID) OF ee oe See Sungei Makapan...... 144307 |....- dO. Sees 405 | 470 | 84 | 67.5 | 45.3 | 15.5 
ID Ome eae eee Kateman River...... 123135 | Female, adult...| 400 | 520 | 80 | 67.5 | 44 15 
1 Xora eats ani dome Saeaies eke | 123136 | Male, immature.| 385 | 480 |..-.-| 62 41.6 | 14.6 
DD Ossie ee os Were ORE Pee ee 123187 | Male, adult.....| 430 | 470 | 81 | 66.8 |...... 15.4 
« Collector’s measurement. 
