588 PROCEEDINGS OF THE NATIONAL MUSEUM. voi. xxxii. 



resembles A. zygomaticus from Pulo Aor in its small lachrjmial, but 

 lacks the heavy zyo-oma and the step-like projection on its infe- 

 rior border. Caudal bristles shorter than in either A. macronrns or 

 A. zygomaticus^ and with the single (in the other species these are 

 usually three to five on a bristle) expansion relatively narrower and 

 longer. The bristles, however, have a worn appearance, which might 

 account for this difference. 



Color. — The color of Atheriirus terutavs so closel}^ resembles that of 

 A. zygomaticus that no detailed description is necessary. 



Skull and teeth. — In general, similar to those of Atherurus macro- 

 itrus, but distinctly smaller, rostrum and nasals relatively shorter, 

 constriction between the orbits more pronounced, depression on top 

 of skull greater; lachrymal bone much smaller, scarcely any of it 

 appearing on the dorsal aspect of the skull; in this respect resembling 

 the skull of A. zygomaticus; zygomata of the same form as in A. ma- 

 crourus; audital bullae, smaller. Teeth of same form as in ^1. macro- 

 urus^ but smaller. 



Measurements. — See table, page 593. Cranial measurements of the 

 type: Greatest length, 93.2 mm. (94.3, 99) ;« basal length, 82.2 (82.6, 

 87.4); basilar length, 76.1 (75.6, 80.5); condylo-basal length, 87.8 (89, 

 94.2); palatal length, 44.7 (45.5, 47.6); greatest length of nasal, 22 

 (25.3, 26.3); zygomatic breadth, 45.8 (45.3, 47.5); least interorbital 

 breadth, 24.5 (26.1, 28.4); maxillary toothrow (alveoli), 15.7 (17.1, 

 17,2); mandibular toothrow (alveoli), 17.3 (17.9, 18.8). 



Specimens examined. — One, the type. 



Reiiiarl's. — Although but one specimen of Atherurus terutavs is 

 known, its peculiarities are so well marked that its specific distinctness 

 from ^4. macrourus and A. zygomaticus can not be doubted. It pos- 

 sesses the peculiar lachrymal bones of A. zygomaticus., but its zygo- 

 mata are exactly as they are in ^4. macrourus from the mainland. 



TRICHYS Gunther. 



1876. TricJiys Gunther, Proc. Zool. 8oc. London, 1876, p. 739, fig. 2; p. 740, fig. 

 2«, p. 741 and pi. lxxi. 



Type. — Trichys lipura.^ from Borneo. 



Species. — Trichys fasciculata (Shaw), from Malacca; T. lipura Giin- 

 ther, from Borneo; T. macrotis Miller, from Sumatra. 



Diagnostic characters. — A small porcupine externally resembling 

 Atherurus but with a relatively longer tail, each scale of which is sub- 

 tended by a single hair and with the brush at end of tail composed of flat, 

 grooved bristles, with parallel sides. (Plate LVIl, fig. 4.) Skull small, 

 different from that of Atherurus in possessing distinct postorbital 



« Measurement in parentheses are those of the type of Atherurus zygomaticus Miller, 

 from Pulo Aor, and of an adult female, Cat. No. 84433, TJ.S.N.M., of A. macrourus, 

 from Trong, Lower Siam. 



