717 



4625. The right fibula. 



This very long and slender bone has an articular expansion at both extremities, the distal 

 one being the largest. The characteristic length of all the long bones relates to the support 

 of the parachute, formed by a wide fold of integument, extending on each side of the body 

 from the fore to the hind extremity. 



4626. The left femur, longitudinally bisected. 



The medullary cavity is long and wide, and its walls compact. 



4627. The left tibia, longitudinally bisected. 



It resembles the femur in structure. 



4628. The mid-incisor of the lower jaw. 



Its crown presents the form of a comb, and is, in this respect, unique in the class Mam- 

 malia. 



4629. A canine of the lower jaw. 



It is implanted by two fangs. 



4630. Four premolars of the lower jaw. 



Genus Lichanotus. 

 Dental formula : i ^, e |=1, p f=f, m |Ej=30. 



4631. The skeleton of the Indri Lemur (Lichanotus Indrf). 



The vertebral formula is: 7 cervical, 12 dorsal, 9 lumbar, 4 sacral, and 9 caudal. ' The 

 atlas has a short hypapophysis, but no neural spine : the transverse process is moderately 

 long and broad and is perforated lengthwise and vertically by the vertebral artery, which 

 afterwards pierces the neural arch. The transverse process is perforated in all the other 

 cervical vertebrae : the pleurapophysial portion of that of the sixth forms a broad lamella 

 directed downwards and outwards : the diapophysial portions, from the second to the 

 seventh cervicals inclusive, are nearly equal in length, and project outwards and backwards. 

 Each of these cervicals has its hypapophysial ridge and neural spine, the hitter moderately 

 long and slightly increasing to the seventh. The broad neural arch is fissured behind. The 

 spines of the dorsal vertebrae are continued of equal length throughout that region. The 



