AUSTRALIAN PHALANGERS. 



phragm, and below is attached to the intermediate cystic 

 lobe, just to the right of the cystic or mesial fissure ; and 

 passing dorsally from the fissure to the inf. v. cava it 

 serves with the fissure to define the left cystic from the 

 rest of the mesial lobe. 



(2.) Pseudochirus. — Diaphragmatic Surf arc. — Here 

 the chief point is the encroachment ventrally of the left 

 lateral lobe, so that it forms the chief portion of the 

 ventral or anterior margin. The gall bladder is seen 

 dextrally, and we distinguish a large right margin and 

 smaller left. The three lobes are defined, viz., small right 

 lateral, large left lateral, and the mesial or cystic lobe, 

 with its three divisions. The dorsal part of the caudate 

 is also seen projecting. The hepatic course of the inf. v. 

 cava, as in Trichosurus, is not visible, only the exit being- 

 noted. Owing to its projection ventrally only a small 

 portion of the left lateral lobe is visible on this aspect. 

 The liver measures dorso- ventrally 9.5 cm., and laterally 

 9 cm. 



(1.) Trichosurus. — Visceral Surface. — Here we 

 notice, as on the diaphragmatic surface, the relatively 

 small size of the right lateral lobe compared with the 

 mesial or left lat. lobe, and in one specimen the left lateral 

 lobe equalled 7 cm. in greatest length, which was double 

 that of the right lateral (including the caudate lobe). 



Left Lateral Lobe. — Is frequently fissured about the 

 middle of its left margin, and may be prolonged as a 

 saddle-flap lobe over the ventral aspect of the stomach. 

 The left lateral fissure separating it from the mesial or 

 cystic lobe is traceable to the portal interval. Dorso- 

 internally is the concavity for the oesophagus, and pro- 

 jecting below the inner extremity is the spigelian lobe. 

 This lobe is related to the left or cardiac portion of the 

 stomach. 



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