Rattus ringens murdoch. R. ringens murdoch of Pona... 3 ♂ (ad), 2 ad ♀ 1 or 2 post-hedling, other 2 embryos (small). All three males breeding (T.e.) Many at Stiki; Soperi, Pona. (apr.1) R. ringens ringens at Wurovi: 2 ♂s both rather young, both pregn. (5 days) at Old Mawatta (apr.10), a ♀ with 5 large embryos - 5 small at Metabuae (april) at Darwinia (1 spec.) (other). At Palmer Jumei (may time) no Rattus of any kind as found. at Black R. and Orville - a ringens rat with up-tiled nostrum at Dutch Binder village ♂+♀ " thickened hind feet at Stewart Isl. 32 ♂, 27 ♀ Tarara R. trachysminis of Dava. Definitely an open grass-land species, about from the palely woods and mangrove swamps. A short-nosed species of the tinnijeri group (possibly = ratticolor Tervink). A few series from Dava taken between Feb. 28 and Mar. 22, offers proof evidence of the proposition that a breeding cycle. Of ♂s bearing embryos the following sequence occurred: Feb. 4. 1 with 5 minute Mar. 7 1 " 6 minute Mar. 7 1 " 7 minute Mar 9 1 " 5 medium Mar. 22 1 " 6 large. From Feb. 28 to Mar 3 no ♂s were trapped. The difference between young breeding and old females (both males) is based topographically upon length of fur and maturity in jocular appearance of the animal. In my opinion we have here four generations: (1) embryos, (2) juvenals resulting from previous cycle of pregnancy, in which various degrees of transition from juvenile to adult pelage appear but no animals are breeding (age about 2 months). (3) Young adults practically breeding (age about 6 months? ) all in breeding condition forr in (♀ 24-30 mm., pelage mature but size of animals still small. (4) Old adults. Two males + two females only trapped. Testes of both males enlarged, one female pregnant, one not. (age a year or more). R. trachysminis is the only species of Rattus indigenous to New Guinea occurring on Tilam Island. The infrequency with which these rats survive predators more than a year is probably shown by the scarcity of such old animals in our collection. at Old Mawatta (apr. 10th) a ♀ newly pregn. (7 tiny embryos) at Metabuae (april). Darwinia savannas (Oct. 77 specimens) G avine (8 spec.) NW. Tarara Pona