CENTETIDA 637 
Family CENTETIDA, 
Skull (Fig. 294) with a small cylindrical brain-case not con- 
stricted between the orbits, no zygomatic arch or postorbital pro- 
cess, and the 
tympanic annu- 
late and not 
forming a bulla. 
Upper molars 
tritubercular. 
Pubic sym- 
physis short; 
and the tibia 
and fibula either 
united or free. 
No cecum. The 
penis is pendent and retractile within the fold of the integument 
surrounding the anus; the testes are abdominal; the mamme are 
thoracic and ventral; and the uterine cornua are terminated by 
the Fallopian tubes. All the species are limited to Madagascar. 
Subfamily Centetinze.—Tibia and fibula distinct; testes near 
kidneys ; fur with spines. 
Centetes.1—Dentition: i $,¢ 4, p 3, m 4; total 38. Vertebre: 
C7,D19,L 5,8 3,C 8. The single species is the well-known 
Tenrec (C. ecaudatus), characterised by the absence of a tail; it 
reaches a total length of from 12 to 16 inches, and is the largest 
known Insectivore. The adult males have long canines, the 
extremities of the lower pair being received into pits in front of 
the upper ones (Fig. 294). It is probably the most prolific of all 
mammals, since as many as twenty-one young are said to have been 
brought forth at a birth. The young have strong white spines 
arranged in longitudinal lines along the back, but these are lost in 
the adult animal, which is provided only with a nuchal crest of 
long rigid hairs. In rare instances a fourth upper molar may be 
developed. 
Hemicentetes.2—Dentition : 1 3, ¢ 4, p 3, m 3; total 40. This 
genus is represented by the two species HH. semispinosus (of which 
the skull is shown in Fig. 295) and H. nigriceps. It differs from 
Centetes by the presence of the third upper incisor, the much smaller 
canines, and by the form of the skull. Both species are very much 
smaller than C’. ecuudatus, and the dorsal spines are retained in the 
adult state. Vertebre: C 7, D16,L5,8 3,09. 
Fic. 294.—Left lateral view of the skull of the Tenrec (Centetes 
ecaudatus). Reduced. 
1 Illiger, Prodromus Syst. Mami. et Avium, p. 124 (1811). 2 Mivart, 
Proc. Zool. Soc. 1871, p. 72. 
