DEVELOPMENT OF UNGULATA. 739 



as usual, and the ovum, with completed germ-mass, has been 

 found iM utero August 16 : l here it lies with uncoated hyalinion 

 until the latter half or end of December : the germ-mass remain- 

 ing four months in a quasi-torpid state. Development is then 

 resumed, and the young are brought forth at the end of April or 

 beginning of May. The contiguous ends of the two elongated 

 ova overlap each other, and as gestation advances the contiguous 

 parts of the exochorion blend together ; but each foetus retains 

 its own unvascular allantoic bag and amnios. 



In the Giraife there are two kinds of foetal cotyledons: the 

 larger or normal ones are in longitudinal rows corresponding with 

 the disposition of the uterine caruncles : they have mostly a 

 reniform figure, attached to the chorion by a contracted base : 

 the terminal branches of the component villi are finer than those 

 in the Cow, and more resemble those in the Deer. The smaller 

 cotyledons, of irregular form and varying size, project from the 

 outer surface of the chorion in the interspaces of the rows of the 

 larger ones : their villi are proportionally shorter, and in the 

 smallest ones simple and unbranched, indicating a transitional 

 step to the diffused villosity in the small Musk-deer. I counted 

 180 cotyledons, large and small, on the chorion of the Giraffe : 

 the umbilical cord is above a yard in length. 



A male and female Giraffe paired, April 1, 1838, and again on 

 the following day, after which the female lost the disposition to 

 receive the male; on June 10, 1839, the udder began to enlarge, 

 and on June 19 the young (a male) was born, 444 days after the 

 second coitus. The same Giraffes paired on March 12, 1840, and 

 after a gestation of 431 days a young male was born. In each 

 case the female stood during parturition : the fore-legs of the foetus 

 first appeared, the head and body followed, the mother stooped 

 behind to deposit her burthen safely. In half an hour the 

 young one made efforts to rise, and in an hour after birth it stood 

 upright. It was born with horns in structure and relative size 

 like those of the dam, 2 and is the only horned ruminant that 

 acquires these weapons before birth. Concomitantly with the 

 long period of gestation is the unusually large size of the new- 

 born young, which measured from the muzzle to the root of the 

 tail six feet ten inches ; from the base of the scapula to the end 

 of the fore-hoof five feet. The enemies to which such a young 

 Mammal might fall a prey in its native African wilds indicate the 

 conditions of the unusual strength acquired during the long 

 gestation. 



1 cclxiii". p. 10, tab. i., fig. 8. 2 ccxxvi". pi. 1. 



3 b2 



