1902 - 3 .] Abdominal Viscera o/Cercocebus fuliginosus, etc. 515 
gradually become flatter and flatter and of increased span because 
of the widening of the trunk. The bearer of a lobed liver, he goes 
on to say, has considerable mobility of the trunk, whereas an 
unlobed liver belongs to an animal with a plumper bodily 
formation (13). 
Evidence, therefore, goes to show that the human liver is the 
most modified in the primate series, and, for this reason, cannot 
logically be employed as the type with which the livers of other 
animals should be compared. As long ago as 1835, Duvernoy (14) 
found a difficulty in comparing different mammalian livers with 
the human organ. He sought to overcome the difficulty by 
assuming that the liver of man was formed of one lobe only (lobe 
principal) with a rudimentary right lobule, that of Spigelius. In 
other mammals he supposed that additional lobes were added to 
the “principal lobe.” This hypothesis was obviously untenable. 
Rolleston (15) suggested that the average mammalian liver con- 
sisted of three lobes — suspensory, right, and left — to the middle of 
which the suspensory ligament is attached. The suspensory lobe 
Rolleston described as being very commonly trifid, the dividing 
lines of its component parts being the position of the suspensory 
ligament and of the gall-bladder. The recognition, as an indepen- 
dent component of the liver, of what has come to be known as the 
caudate lobe, is also due to Rolleston. He described it as the 
“right kidney lobule.” Owen (16), writing a few years later, 
agreed in the main with Rolleston, and criticised Duvernoy’s views 
in saying that “fissures, rather than lobes, are added to the liver 
of quadrupeds.” 
Since subsequent workers have found very little to alter in it, 
Flower’s conception of the arrangement of the lobes of the liver 
(6 and 17) forms one of the most valuable contributions to the 
subject. He considered the liver as primarily divided by the 
umbilical vein into two segments, right and left. In the majority 
of mammals each segment is further divided by a fissure — the 
right and left lateral fissures. In such a case the lobes lying on 
each side of the umbilical fissure are known as the right and left 
central lobes, and those beyond the lateral fissures as the right 
and left lateral lobes. Rex (18), writing in 1888, confirmed 
Flower’s divisions and merely offered a different nomenclature, in 
