OF THE SPERM WHALE 
85 
the fifth rib is articulated by its posterior articulating 
surface to the transverse process of the fifth vertebra, 
and by its two anterior articulating surfaces between and 
to the bodies of the fourth and fifth dorsal vertebra 
the same kind of articulation is followed to the eighth 
rib, the ninth being merely attached to one surface on 
the transverse process of the ninth dorsal vertebra ; the 
tenth and last is articulated also by one surface to the 
transverse process of the tenth dorsal vertebra. The 
first rib is in span 4 feet inches, and forms an arch 
of 1 foot 8 1 inches in height, — the second rib is in span 
5 feet 6| inches, and forms an arch of 2 feet 4| inches 
in height,— -the third rib is in span 6 feet, and forms an 
arch of 2 feet 9| inches,— the fourth rib is in span 6 
feet 4| inches, and forms an arch of 2 feet 9| inches in 
height,— the fifth rib is in span 6 feet \ an inch, and 
forms an arch of 2 feet 10 \ inches, — the sixth rib is in 
span 5 feet 11 inches, and forms an arch of 2 feet 8 
inches in height. The rest of the ribs become rapidly 
shorter and straighter, until we find the tenth and last 
having a span of 4 feet 3 inches, and forming an arch 
of 1 foot and \ an inch only in height. The first rib 
is an exception to the general form of the others, it 
being fiat and broad like the human, the rest of the 
ribs being nearly round ; it is in width inches, and in 
thickness 3 inches, the fourth measures 3\ inches by 4 
in diameter. The length of the cartilage of the fifth 
rib must have been about three feet. 
