THE CCELOM 



41 



muscular fibres ' in the oblique septum of the duck ; and in 

 the puffin ' {Fratercula arctica) and the penguin {Eudyptes, 

 Eudyptula minor and Spheniscus demersus) the posterior 



Pig. 26. — Diagbam of a Tbansvbbse Section through 

 Thokax of Duck. 

 i.£, jK.i, Ipbes of liver ; Z, lungs; A.S, horizontal septum ; O.S, obligue septum. 



Fig. 27. —Similar Diagram ov Crow (Corous capellanus). 

 a, rudiments of sternal attachment of oblique septum. Other letters as in fig. 26. 



part of the oblique septum is largely covered with a thickish 

 layei: of muscular fibres, which Pilhol ^ (their describer in 



' Beddabd, ' Notes on the Visceral Anatomy of Birds,' II. ' On the Eespi- 

 ratbry Organs in certain Diving Birds,' P. 2. S. 1888, p. 252. 



^ ' Sur la Constitution du Diaphragme des Evidyptes,' Bull. Sac. Philom. (7), 

 vi. p. 235. 



