18/9.] PROF. A. H. GARROD ON GELADA RUEPl'ELLl. 455 



connected by a bridge of hepatic tissue. The inferior margin of the 

 right central lobe is straight, and at right angles to the axis of the 

 gall-bladder, which latter organ is deeply imbedded in a cystic fossa, 

 never deep enough to appear on the diaphragmatic surface. The 

 fundus of the gall-bladder never reaches the inferior margin of the 

 organ, though it approaches very near to it. There is no trace of a 

 cystic fissure. The interval between the inner border of the cystic 

 fossa and the umbilical fissure is always broad, a quadrate lobule 

 intervening. The left central is generally the smallest of the four 

 main lobes, it being vertically elongate. The left lateral lobe is 

 shaped much like the sector of a quarter of a circle, with the apex 

 directed to the portal fissure. This apex is often simple; but when 

 not so a slight fissure runs for a short distance from the superior 

 border of the lobe, not far from the apex, parallel to the left lateral 

 fissure. The right lateral lobe is subquadrate in form ; its surface 

 presents no irregularities, as a rule ; but when present they take the 

 form of deep semilunar incisions on its abdominal surface. The 

 abdominal margins of the umbilical fissure frequently present small 

 lobelets of a bluntly conical form, with their apices directed down- 

 wards. These are most frequently situated on the left central lobe, 

 but sometimes on the right, sometimes on both. The caudate lobe 

 is elongatedly subfusiform, without any renal depression ; its apex 

 reaches as far as the extreme right margin of the right lateral lobe. 

 The Spigelian lobe is well marked, being small and thin ; its shape 

 is that of the tip of the compressed finger of a glove ; it is directed 

 backwards. 



The genus Cercopithecus differs from Maeacus in the following 

 respects : — The iuferior margin of the right central lobe is rarely 

 anything approaching a straight line at right angles to the axis of the 

 gall-bladder ; a slight notch often also indicates the rudiment of a 

 cystic fissure. The imbedded fundus of the gall-bladder is likewise 

 generally visible on the diaphragmatic surface of the right central 

 lobe. The interval between the left margin of the cystic fossa and 

 the umbilical fissure is narrow, and often not more than a sharp 

 vertical ridge of hepatic tissue. The apex of the left lateral lobe 

 (directed, as in Maeacus, towards the portal fissure), when com- 

 plicated, is rendered so by a short fissure running from the superior 

 border of the lobe, not parallel to the left lateral fissure, but down- 

 wards and inwards, so as to produce a subtriaugular lobelet, in which 

 the free margin is directed horizontally upwards. When com- 

 plicated the right lateral lobe develops lobules on its abdominal sur- 

 face, not semilunar incisions. The caudate lobe runs to the extreme 

 margin of the right lateral lobe, as in Maeacus. The Spigelian lobe 

 is frequently absent, and when present is irregular and much smaller 

 than in Maeacus. 



In the genus Cynocephalus the peculiarities of Cercopithecus are 

 observed, except that the caudate lobe is very short, only extending 

 half across the right lateral lobe horizontally. The Spigelian lube 

 is also well developed, quite as much or even more so than in 

 Maeacus, it being thicker than in that genus. 



