692 ON THE ANATOMY OF THE EPOMOPHORI. [June 7, 



glossus muscle. The small genio-liyo-glossi arise on each side from 

 the anterior margins of the epihyals. 



From the pharynx, thus closed in by osseous and mnscular walls, 

 no sacs extend outwards as in E. franqueti ; but near the com- 

 mencement of the oesojjhagus, opposite the opening of the larynx, 

 there is the aperture of a single central sacculus, which lies 

 between the middle constrictor of the pharynx and the spine, its 

 neck passing between the fibres of that muscle, which forms a 

 lozenge-shaped sphincter round it. It is difficult to suggest the 

 office of this sac, the cavity of which in E. macrocephalus is not 

 larger than a small bean, and in E. minor would hardly hold a pea. 



Owing to tlie presence of the large inflected extremities of the 

 thyrohyals, which nearly meet in the middle line across the com- 

 mencement of the oesophagus, the inferior constrictors of the pharynx 

 are much shorter, and do not form a pair of long fleshy tendons 

 carried forwards longitudinally between the extremities of the epi- 

 hyals as in E. franqueti ; while the middle constrictors are dis- 

 tinguishable from them, and part of their fibres form a sphincter for 

 the neck of the sacculus above described. 



The remarkable form of the hyoid bones and great development 

 of the isthmus faucium part of the pharynx, in which (though 

 especially pronounced in tlie males of certain species) all the species 

 agree, may be understood when we consider the nature of the food 

 of these animals. 



In the collection of the British Museum are specimens of E. gam- 

 hianus from the banks of the Zambesi, with the note " eating figs " 

 on the label attached to them by the donor Dr. Kirk. That figs 

 constitute the food of E. franqueti, macrocephalus, labiatus, and 

 minor also I have proved by finding remains of these fruits in the 

 alimentary canals of these species. 



The fig being a hollow receptacle containing numerous small fruits, 

 is not easily detached from the branch for the purpose of masti- 

 cation ; and its outer rind is evidently too tough to be readily torn 

 through by the feeble teeth of the Epomopliori. The easiest method, 

 therefore, of getting at its soft juicy contents is by sucking them out 

 through the aperture at the distal extremity of the fig. 



Now the whole structure of the mouth and ])harynx of these 

 animals is admirably suited for this purpose. The peculiarly volu- 

 minous lips are capable of completely encircling the fig, and their 

 adherence to its smooth surface is evidently securely maintained by 

 the soft pads which spring from their upper margins near the angles 

 of the mouth. While thus encircled by the lips, the fruit is pro- 

 bably slowly chewed by the feeble acutely pointed teeth, and pressed 

 upwards against the prominent palate-ridges so as to cause it to 

 give up more freely its juices and soft contents, which are drawn out 

 by suction through the terminal aperture. 



The construction of the parts above described is specially suited 

 to the action of suction, accomplished probably by the alternate 

 action of the buccal muscles and the lungs. The spacious pharynx, 

 shut off from the nasal apertures by the constrictors of the pharynx. 



