ANTHROPOIDEA 



707 



from that of the Simiidce by the deeply cleft lateral fissures, and 

 has a comparatively small and pointed caudate lobe. The enormous 

 size of the stomach in Colobus causes the liver to be very narrow, 

 and pushed to the left side. The liver of the Cebidce (Fig. 336) 

 and Hapalidce, in ad- 

 dition to the deeply 

 cleft lateral fissures, is 

 characterised by the 

 great size and quad- 

 rangular form of the 

 caudate lobe (c), which 

 attains its maximum 

 development in A teles. 

 The gall-bladder is 

 always present. 



The larynx is in many 

 Apes furnished with sac- 

 like appendages, which 

 are variable in different 

 species as regards 

 number, size, and situ- 



, . mi i FIG. 336. Under surface of the liver of the Black-handed 



OH. iney may e gpjder Monkey (Aides mdaiiochir). u, Umbilical fissure ; 



dilatations of the laryn- vc, vena cava ; U, left lateral lobe ; fc, left central lobe ; re, 



geal ventricle as in "8^* cen tral l De ; rl, right lateral lobe ; s, Spigelian lobe ; 



7J. . , c, caudate lobe ; a, gall-bladder. 



Simla, Gorilla, and 



Anthropopithecus, or they may open above the false vocal chords 

 so as to be extensions of the thyro-hyoid membrane, as in Hylobates. 

 There may be but a single median opening in the front part of 

 that membrane at the base of the epiglottis, as in the Cercopithecidce. 

 There may be a single median opening at the back of the trachea, 

 just below the cricoid cartilage, as in Ateles ; there may be but a 

 single sac, or there may be five, as sometimes in Mycetes. These 

 may be enormous, meeting in the middle line in front and extend- 

 ing down to the axillae, as in the Gorilla and Orang. A sac may 

 occupy the cavity of the expanded body of the hyoid, as in Mycetes. 



The hyoid has its basilar part generally somewhat more convex 

 and enlarged than in Man ; but in Mycetes it becomes greatly enlarged 

 and deeply excavated, so as to form a great bony bladder-like structure. 

 The posterior cronua of the hyoid (thyro-hyals) are never entirely 

 absent, but the anterior or lesser cornua may be so, as in Mycetes. 

 The anterior cornua never exceed the posterior cornua in length ; 

 but they may be (e.g. in Cercopithecus) more largely developed 

 relatively than in Man, and may even be jointed, as in Lagothnx. 



The lungs have generally the form of those of man ; but the 

 right lung may have four lobes, as in Hylobates. The great arterial 

 trunks in Simia, Gorilla, and Anthropopithecus are arranged as in 



