Royal Society of Edinburgh, 69 



system to which it belonged at first appeared confused, yet still there 

 was method in the complexity. Through nearly the whole animal 

 series, its agency might be traced from the most simple up to the 

 most complicated; in those instances where respiration was per- 

 formed only by the air playing upon the surface ; by its being ad- 

 mitted into some simple sac, or into tubes, or by then leading to 

 viscera. Even after this, it became associated with other functions, 

 as of taste, smell, speech, &c. No wonder then that it was complex ; 

 both vital and voluntary actions being most closely associated with it. 

 For example, the throat was a common passage for respiration and 

 deglutition ; and how admirable that there is so little interference ! 

 Directions were given for tracing the portio dura from the surface to 

 its true origin, in a flat layer spreading out on the pons Varolii or 

 nodus cerebri ; its relation to the spinal cord was then shown, as that 

 of other nerves, the 8th, 6th, and 4th ; its cause and distribution 

 was then stated, corresponding to its varied functions, on the lips 

 and other parts connected with speech, on expression generally, the 

 play of the features, not excluding the eye. That every fibre and 

 aperture of the countenance is associated with respiration, is now too 

 clear to be disputed ; direct experiments, as well as many of the phe- 

 nomena of health, and yet more of disease, most strikingly demon- 

 strate it. It acts in laughter, not negatively, or as the result of 

 defective influence, but positively ; so in extreme pain, in passion, &c. 

 In his next paper the author means to point out in what respects this 

 nerve differs from others. 



Dr. Macdonald made a verbal communication on the Osseous 

 Structure of Fishes. 



The author had scarcely time to do justice to himself or subject, 

 and we have still less in our limited space. He stated he thought 

 zoologists attended too little to anatomy, those especially who gave 

 themselves to tracing analogies throughout the scale of animated 

 nature. He avowed himself an advocate for the quaternary not the 

 quinquennary grouping of the series. His attention was first directed 

 to the structure of fishes, when comparing the fourth or last portion 

 of the first great circle, viz. the vertebrata, with insects. The ana- 

 logies here were striking, but great mistakes are generally committed 

 regarding them. Starting from the views propounded by Carus, of 

 three important portions being fundamental, and which, in ascend- 

 ing, are converted into the jaws, the limbs, wings, &c. he traced 

 these modifications through the series. Entomologists have almost 

 universally erred in establishing analogies with the more complicated 

 classes of animals. They state that the lower part of the anterior 



