6 D 1 '. F. A. JENTINK. MAMMALS. 



ribs, lumb. 7, sacral. 4 and caudal. 31, like in Hydromys chrysogaster (Flovver. An Introduction 

 to the Osteology of the Mammalia, 1885, p. 85). 



5. Parahydromys asper Thomas. 



Dr. LORENTZ had the good luck when on the Hellwig-Mountains, September 3. 1907, 

 of discovering in a native trap a rat-like animal; although it wasin a very poor condition 

 he could préserve the skin and the skull also. I call it a good luck ; for the animal now turns 

 out to be a spécimen of the most interesting Parahydromys asper, only known from the 

 type-specimen in the British Muséum, and never seen by later explorers of New Guinea. 

 The type-specimen, an adult maie, described by OLDFIELD THOMAS (Ann. and Mag. Nat. 

 Hist., 1906, Ser. 7, Vol. XVII, p. 326), had been captured at an altitude of 2000 — 4000 feet, 

 on Mount Gayata, Richardson Range, British New Guinea. Dr. LORENTZ' spécimen, also an 

 adult maie, lived at 2200 meters. It is highly interesting to note that notwithstanding our 

 animal belongs to the Hydromys-ty^ç. ( 2 / 2 molars and well developed webbed feet and therefore 

 is an aquatic-rat) it nevertheless is living on such high mountains and at distances the one 

 from the other of several hundred miles linea recta; it therefore apparently belongs to the 

 so called "Reliktenfauna". 



The description of this fine water-rat and the dimensions of it as given by OLDFIELD 

 THOMAS are so punctually those of our spécimen, that I only hâve to add some drawings 

 of the peculiarly shaped skull (fig s . 7, 8 and 9), which differs so widely from the common 

 Hydromys-skuW as well as from ail other murine-skulls. 



OLDFIELD THOMAS had created a new generic title, Limnomys, for this remarkable 

 animal ; later on he changed that title in Drosomys, Limnomys being a preoccupied name ; 

 however Mr. POCHE having found out the thing some months before and, taking advantage 

 of the favourable opportunity, accordingly changed Thomas' Limnomys in Parahydromys, a 

 name said POCHE "um ihre nahe Verwandtschaft mit Hydromys zum Ausdruck zu bringen" 

 (Zoologischer Anzeiger, 1906, p. 326); THOMAS observed it to be a clumsy name. 



MUS. 



Generally the members of the genus Mus hitherto described as living in New Guinea 

 hâve head and body longer than tail, viz : ruber, Goliath '), barbatus" 1 ), terrae reginae,praetor, 

 mordax, Brozvni and Gestri; one, viz. exidans, from New Guinea (after Trouessart, Cat. Mam- 

 malium, 1904, p. 372), has head and body of about the same length as tail; the other ones, 

 Doriae, Albertisii, vcrecundus and niobe hâve a tail longer than head and body. Although 

 such measurements hâve as a matter of fact a very relative value as having not always 

 been taken when the animal in the flesh, they however give a rather fair idea of the compa- 



1) Mus Goliath is accordingly Milne-Edwards "un peu plus petit que le Mus Armandvillci" ; however he gave 

 no measurements. 



2) By a slip of the pen the measurements given in the Bulletin du Muséum d'Histoire naturelle, T. 6, 1900, p. 

 167, hâve been given as 0.27 cm. (longueur du corps et de la tête), 0.21 cm. (queue) and 0.06 cm. (pied), instead of 

 27 cm., 21 cm. and 6 cm. After Oldfield Thomas barbatus is a member of the £><7OTr.r-group. 



