forming a complete septum between the thorax and abdo- 

 men, (b) great development of spleen, (c) development 

 of great omentum. Great omental development is prim- 

 arily correlated to great splenic development. With the 

 assumption of the erect position in man, the great omen- 

 tum is a factor in supporting the transverse colon. A 

 human omentum that was free of transverse colon would 

 be one liable to torsion, and this would be more likely on 

 the left than on the right side. 



In these studies variability is shown as regards the 

 position of entrance of bile ducts relative to the pyloric 

 sphincter and duodeno-intestinal junction, and also in the 

 relation of the pancreatic to the bile duct ; so that prob- 

 lems referring to digestive function are raised. In a 

 typical section of the human pancreas the areas of Lan- 

 gerhans may be difficult to define; but in histological 

 sections of the pancreas of, e.g., the Wombat or Tas- 

 manian Devil, numerous areas are to be met with. 



Many other functional problems might be mentioned, 

 but these few examples are cited to show what a rich 

 field is open to the medical research scholar. 



In conclusion, the writer wishes to thank the Presi- 

 dent and Council of the Royal College of Surgeons of 

 England, and also Professor Arthur Keith, for facilities 

 accorded him while working in the laboratories of the 

 Hunterian Museum; Professor Sir Baldwin Spencer and 

 Mr. Kershaw for the privilege of conducting researches 

 at the National Museum in Melbourne; the Editor of the 

 "Journal of Anatomy' 1 for permission to reprint his 

 article on the Spleen in Vol. LI. of that journal; his 

 cousin, Major Charles Mackay, for valuable help in the 

 preparation of the dissections; and also Mr. Finerty, of 

 London, and Miss Esther Paterson and Mr. Victor Cobb, 

 of Melbourne, for the excellent illustrations. 



VI. 



