HYSTRIX 549 



molars but sliowing more tendency to irre;ij;ulai'ities. Lower 

 teeth with the same pattern reversed, the outer side with one 

 simple, oblicjue, backward sloping fold, the inner side with three 

 folds, the posterior and middle of which are usually simple, the 

 anterior complex and tending eventually to become divided into 

 two or three irregularly shaped islands arranged somewhat in a 

 spiral. The premolar shows the same tendency as the corres- 

 ponding upper tooth to become irregular in details of enamel 

 pattern, though the fundamental plan of its folds appears to be 

 always the same as in the molars. 



MeaHurenwnts. — Young adult (probably female) from Vizzir.i. 

 Sicily (apj)roximate) : head and body, 600 ; tail, 40 ; hind footj 

 75. Immature individual from Province of Rome, Italy (approxi- 

 mate) : head and body, GOO ; tail, 50 ; hind foot, 85. For cranial 

 measurements see Table opposite. 



Specimens e.ramincd. — Seven, from the following localities : — 

 Italy: Near Rome, 4 (B.M. and U.S.N.M.) ; Vizzini, Sicily, 2; no 

 exact locality, 1 (Stockholm). 



3. Rome, Italv. Genoa IMuseum (e). 97. 2. 22. 1-3. 



2, juv. Vizzini, Sicily. J. I. S. Wliitaker (p). 3.4.21.1-2. 



Family MUSCARDINID^. 



1821. Mijoxidce (misprinted Myosidie) Gray, London Med. Repos., xv, 



p. 303. April 1, 1821. 

 1857. Mijoxina Blasius, Saugetbiere Deutschlands, p. 285. 



1898. Gliridx Lydekker, Zool. Rec. xxxiv. (1897), Mamm. p. 27, 1898. 

 Not of Ogilby, 1837. 



1899. Mmcardlnidx Palmer, Science, N.S., x, p. 413, September 22, 1899. 



Geographicnl distribution. — AVarmer portions of the Old World 

 from Japan to England and from central Sweden south through 

 Africa. Absent from Madagascar, the Malay Archipelego and 

 Australia. 



Characters. — In general as in the Maridye (p. 591) but 

 Ciecum absent, jugal bone larger and forming a more important 

 mechanical part of zygoma (in some genera approaching the 

 condition characteriatic of the Sciuridw), angular process of 

 mandible bent outward at middle so that its lower border 

 bears a noticeable secondary angle, and cheek-teeth always 

 rooted, brachyodont, their crowns with transverse cross ridges 

 variously arranged and .".ometimes obsolete, but referable to a 

 primitive 3-ridged pattern ; one premolar typically present in 

 each jaw. 



Roiinrlcs. — Six genera of Mmcardinidse are currently recog- 

 nized, four of which occur in Europe. They are mostly arboreal 

 animals with habits and aspect somewhat intermediate between 

 mice and squirrels, but readily distinguishable from the Muridae 



