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skull bones contain air-spaces, which are in communication with the 

 nose. The two upper incisors are long ivory tusks. Canines absent. 

 The grinders are very large ; one or at most two are developed at a 

 time, but the succession numbers six for each side of each jaw. 



Dental formula is either - - or 1( The two teats are pectoral. 

 0033 0006 



Indian Elephant. 



Enamel ridges on (worn) grinders 



are parallel. 

 Tusks (incisors) well developed 



in male only. 



Five nails on manus, four on pes. 

 End of trunk has only one " lip." 



External ears moderately large. 



African Elephant 



Enamel ridges on (worn) grinders 



are lozenge-shaped. 

 Tusks well developed in both 



Four nails on manus, three on pes. 

 End of trunk has two " lips " of 



equal size. 

 External ears very large. 



State the Principal 'Distinguishing Characters of the Artiodactyla. 



An even number of digits (even-toed) ; third and fourth digits 

 large and of equal size, the others vestigial or absent. Astragalus 

 articulates with navicular and with greater part of cuboid. Femur 

 without a third trochanter. Horns, when present, are either out- 

 growths of frontal bonep, or epidermal horny sheaths on basal bony 

 cores. Stomach complex ; caecum small. Teats few and in the 

 groin, or numerous and along the abdomen. Placenta non-deciduate. 



How do the Horns of the Gervidae (Deer) differ from those of the 

 Bovidae (Antelopes, Cattle, Sheep, Goats)? 



The horns (antlers) of Deer are outgrowths of the frontal bones. 

 During growth the horns are covered by the vascular skin or "vel- 

 vet " ; and when the limit of growth is attained, a circular ridge 

 (the burr) is developed near the base of each horn, and the " velvet " 

 covering them peels off. Annually the antlers are shed (at the htm-) 

 and re-grown from the remaining stumps. 



The horns of Antelopes, Cattle, Sheep, etc., are never branched 

 (except Antilocapra), and are hollow horny (epidermal) sheaths 

 covering basal bony cores (outgrowths of frontal bones). The horn 

 and core are permanent, are never shed. 



Describe the Stomach of a Ruminant (e.g., Sheep), and explain the 

 Process of Rumination or " Chewing the Cud." 



The distinct sac-like regions of the " stomach " are the 

 rumen or paunch, the reticulum (with a honeycombed mucous mem- 

 brane), the psalterium or manyplies, so-called from the numerous 

 deep leaf-like folds of its inner lining, and the abomasum or reed, 

 which has a ridged inner wall lined with the glandular epithelium 

 that secretes the gastric juice. 



