220 FHILOSOPHICAL TRANSACTIONS. [aNNO 1705. 



jlccount of a Booh. By James Douglas, M. D. viz. De Aure Humana Trac- 

 tatus; in quo Integra Auris Fabrica, multis novis InventiSf et Iconismis illus- 

 trata, describitur; omniumque ejus Partium usus indaganlur. Auctore An- 

 tonio Maria Valsalva* Imolensi. M. D, ^c. Bononiit 1704. Ato. N° 299, 

 p. J 978. 



The authour divides the human ear into 3 cavities, viz. the external, which 

 contains the auricle, and the auditory passage; the middle, which comprehends " 

 the tympanum, or cavity of the barrel, in which are the four little bones, &c ; 

 and the internal, which contains the labyrinth, which he farther divides into 

 the vestibulum, the semicircular canals, and the cochlea. The prominence 

 called helix ends in the lobe of the ear, which it constitutes, and that called 

 anthelix terminates in the antitragus. He gives the common names to the 

 cavities that lie between the eminences of the auricle, and divides the concha 

 into two cavities, viz. the superior and inferior. 



Under the skin of the auricle he takes notice of a great number of glands, 

 which, from the likeness of the humour they separate to that of tallow or 

 sebum, he calls glandulae sebaceae : which liquor being carried to the surface of 

 the skin, he alleges hardens there, and turns into a scaly greasy substance, 

 much like to that of bran. That there are abundance of such glands under 

 the skin of the head, he thinks that the greasiness of the hair, and the dandrifF 

 combed from the head, may be a sufRcient proof. The lobe of the ear, and 

 the lower part of the helix, are made up of a duplicature of the common in- 

 teguments, without any cartilage; in no part of the auricle, except in these 

 two, is the membrana adiposa conspicuous. Besides the commonly described 

 processes or eminences of the auricle, formed by the windings of its cartilage, 

 he takes notice of another that is small and acute, situate near the beginning 

 of the auditory passage. 



He has discovered some little glands, of the conglobate or lymphatic kind, 

 which, with respect to their situation upon the tragus, he calls glandulae tragi : 

 these are sometimes 3 in number, sometimes 2, but for the most part there is 

 only one of them to be found in each auricle. To the 4 external muscles of 



i * This Italian physician was a very expert anatomist, and afforded great assistance to Morgagni 

 in the dissection of morbid bodies. Besides the abovementioned treatise on the ear^ he read several 

 dissertations before the Academy of Bologna, wherein he presented many new observations on the 

 structure and diseases of the eye What he took for excretory ducts of the renes succenturiati, were 

 afterwards shown by Ranby (Phil. Trans. VoL xxxiii.) to be blood-vessels. Valsalva died in 1723« 

 aged 67. 



