OK THE CESOPHAGUS OF THE BUMINANTIA. 53 



The (Esoplaagus of the Euminantia*. By William Euthereoed, 

 M.D., Eesident Surgeon, Eoyal Infirmary, Edinburgh ; formerly 

 Demonstrator of Anatomy at the Eoyal College of Surgeons, 

 Edinburgh ; President of the Eoyal Medical Society. Com- 

 municated by John Andeesok, M.D., F.L.S. 

 [Plate III.] 

 [Eead June 16, 1864.] 



The muscular structure of the oesophagus of the Euminantia 

 seems to have been a subject which, nearly two centuries ago, 

 attracted a considerable share of attention ; for, in Peyer's work 

 on the Euminantia, the opinions of no fewer than twelve distin- 

 guished anatomists are quoted in reference to it. 



In recent times it has not, so far as I have been able to ascer- 

 tain, been re-examined, except perhaps by Mr. Spencer Cobbold 

 (Todd's Cyclopaedia of Anatomy and Physiology). 



I have not been able, however, to meet with any description 

 which at all approaches the truth, I wiU briefly allude to the 

 opinions of previous authors before giving the results of my own 

 investigations. 



The first writers on this subject appear to have been Apo- 

 nensis and ^mylianus, who said that the muscular fibres are 

 arranged in two layers, the outer consisting of longitudinal, the 

 inner of transverse fibres. 



Aquapendentius and Gruilandinus accepted this description ; 

 and Gralen expressed the opinion, that while the food was swal- 

 lowed by all the fibres, it was returned to the mouth through the 

 action of the transverse ones only. On the other hand, Fabricius 

 and Eallopius went so far as to say that the Euminant's oeso- 

 phagus contained no muscular fibres at all, but that it was 

 composed of a peculiar tissue met with in no other part of the 

 animal. 



Stenson described the muscular fibres as forming double 

 spirals, the bundles running spirally from one end of the oeso- 

 phagus to the other, forming two layers, which interlace at two 

 raphes ; so that the same bundle, while running from one end 

 to the other, lies alternately in the inner and outer layer. 



* Being a portion of a Thesis for wliich a Gold Medal was awarded by the 

 Senators of the University of Edinburgh at the Graduation in 1863. The Thesis 

 was accompanied by numerous dissections and models, which were examined 

 and approved of by Professor Goodsir and the other Members of the Medical 

 Faculty, and are now in the University Museum. 



LINK. PEOC. ZOOLOGT, TOL. VIII. 5 



