PAPERS OX BIOLOGY AND AGRICULTURE 



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vrhile upon the ventral surface a similar fusion is eviden- 

 ced: so that paired sphenoids, temporals and auditory 

 bulla are duplicated in the structure (Figs. 6, 9, 10). 



EXPLANATION OF FIGURES. 



Visceral mass of double monster pig. 

 Stomachs and intestines of visceral mass teased apart. 

 Paired hearts and main trunks of circulatory system. 

 Ventral view of liver of large pig. 

 Ventral view of liver of smaller pig. 



Tracheae, oesophagus and larynges with their connections. 

 Dorsal view of compound encephalon. 



Dorsal view of posterior portion of compound encephalon. 

 Dorsal view of fused skull. 

 Fig. 10. Ventral view of fused skull. 



ABBREVIATIONS USED. 



LITERATURE CITED. 



Carey, Eben; 1917 — The anatomy of a double pig. Syncephalus Thora- 

 cophagus, with especial consideration of the genetic significance 

 of the circulatory apparatus. Anat. Rec. Vol. 12. 



Williams, S. R. and R. W. Rauch; 1917— The anatomy of a double pig. 

 Anat. Rec. Vol. 13. 



