TRANSACTIONS OF THE SECTIONS. 173 



large share in the formation of the cranial walls, the epiotic are excluded ; and 

 when the epiotic are largo and admitted into the cranial walk, the exoccipitals are 

 excluded. 2. The neural spine is only present in the active species which have a 

 large cerebellum to protect, aud it is "never divided. 3. The detached petrosal of 

 Professor Owen is found in all species having the pectoral tin attached to the occi- 

 pital segment, and always receives the lower prong of the suprascapida. The 

 paper was illustrated witn photogi-aphs of the skulls and vertebrae alluded to. 



On the Connexion between the Functions of Respiration and Digestion. 

 By George Robinson, M.D., Newcastle-on-Tyne. 



In a paper " On the Nature and Source of the Contents of the Fcetal Stomach," 

 communicated to the Royal Society of London in 1847, and published in the 

 * Edinburgh Monthly Journal of Medical Science ' in the same year, I described 

 certain observations on the contents of the stomach in fcetal and newly bom rab- 

 bits, which seemed to me to prove the existence of a direct connexion between the 

 function of respiration and the secretion of the gastric juice. I am not aware that 

 the vital law thus indicated has yet received much attention either from physiolo- 

 gists or medical practitioners ; and as I believe it to be one of some importance in 

 the animal economy, I hope to be excused for now desiring to submit it to the con- 

 sideration of this Association. The facts which, in my opinion, establish this prin- 

 ciple are very simple, and can readily be examined by any one. 



Immediately before birth, the stomach of the foetal rabbit contains a dark-green, 

 viscid, highly albuminous liquid, which scarcely affects litmus-paper; but after 

 respiration has been established a few hours, the same substance is found firmly 

 coagulated, and the whole contents of the stomach are sh'ongly acid. This for- 

 mation of acid gastric juice does not take place immediately after birth; for I have 

 then observed the lungs inflated, and the contents of the stomach nevertheless 

 unchanged. The process of respiration must continue for a certain time — a few 

 hours — before the coagulation of the albuminous matter by an acid gastric secretion 

 is accomplished. 



The chemical changes therefore which occur in the stomach of the rabbit conse- 

 quent on the pei-fonnance of respiration, and the veiy circumstance of a certain in- 

 terval elapsing between the commencement of the oxygenation of the blood and 

 the appearance of the proper gastric juice, seem to me conclusive as to the connexion 

 between the latter function aud the former. 



Now assuming for the present the con-ectness of this principle, some interesting 

 questions arise. _ If the secretion of the acids of the gastric juice be thus dependent 

 on the oxygenation of the blood, to what extent is the formation of the other ani- 

 mal acids also influenced by the action of respiration I' And if a certain degree of 

 oxygenation of the blood be requisite for the natural secretion of gastric juice, will 

 not defective oxygenation impau- the quality of the latter liquid, and so tend to 

 connect some fonns of indigestion with the imperfect performance of respkation? 

 In this way, the improved appetite and digestion which we often obsei-ve to follow 

 change of residence may really be a direct eftect of the more complete purification 

 and oxygenation of the blood by increased exercise and the inhalation of a piu-er 

 air. 



I can only hope that these and similar questions will be studied by competent 

 chemical physiologists, and that the residt of their researches will be still further 

 to establish the mutual relation and dependence of the great functions of life ; for 

 at the present time, when physiological and pathological inquiries are so intensely 

 localized, it becomes peculiarly important to recall to mind the essentially compound 

 unity of the living animal. 



On the Anatomy of Pteropug. By Professor Rolleston, M.D.,lF.B.S. 



On some Points in the Anatomy of Insectivora. 

 By Professor Rolleston, M.D., F.E.S. 

 The author confined his attention chiefly to the mole, the shrew, and the hedge- 

 hog—the three species found in this kingdom. The subject, he said, enabled us to 



