8 IKTIIODUCTION. 



tuted under the name of ''Minute Atmtomy" to designate those 

 niorpliological studies whit-h aie siiecially concerned with the inves- 

 tigation of the minute or niicroscojiic structures and tissues of which 

 hving beiiigs are com])Osed, apart from the grosser and more jjalpable 

 features of form and structuie. 



Pjivsiolooy. — In its l>roadeMt sense, Pljysiology may be stated 

 to be the scimtce of life niid riUil jiliriiiniii'nii, — understanding by 

 "science, " knowledge methodised and leduced to its principles. In 

 other words. Physiology deals with i\w faniiiuiis exercised by living 

 bodies, or by the various <letinite ]]aits or "organs" of which most 

 living beings are made nji. JA<r^//)o/(«/// teaches us the structure of 

 the animated machine ; PhjixluhHfji shows us what the machine can 

 <lo, and what are the use and jiurpose of the various parts of which 

 the machine is composed. 



The study of the functions discharged by the human organism 

 constitutes a distinct Iiranch of Physicjlogy to which the name of 

 Hiimitii P/it/xinlnij)/ is a]i[p|ied ; whilst C'l/mpdratire J'/ii/sioIocijt/ is con- 

 cerned with the stuily of the vital phenomena exhibited by the lower 

 animals. 



All the vital actions of the organism — in other words, all jjhysio- 

 logical phenomena — may 1m' roughly divided into the following three 

 groups :— 



1. Funii/innxof iiulritiii'ii, comprising the various functions by which 

 the organism is enabled to live, grow, ami maintain its existence as 

 an iiiih'riiliiiij. 



2. Fnuii-ioiix of rcjirodiKiioii, conijjiising those functions whereby 

 fresh individuals are pi-odnced, and the jieijietuation of the specie.'^ is 

 secured, whilst the original individual jierishes. 



3. Fu)irtioiix of re/iifinit^ comprising all those fimctions (such as 

 sensation and the ])Ower of voluntary movement) whereby the outer 

 world is brought into n'/o/ion with the organism, and the organism 

 ill turn is enabled to react upon the outer worlil. 



The functiciiis i^f nutrition and reproduction are essential to bare 

 existence, and are sometimes spoken of collectively as the "vegeta- 

 tive" functions, as being common to animals and jilants alike. On 

 tlie other haml, the functions of relation are often spoken of as the 

 " animal " functions, since they are most highly developed in animals. 

 Various ])lants, howevei', are endowed with the ])ower of movement, 

 and exhibit sensibility e(|ual in aULouut and apjiarently sinular in 

 kind to that manifested by many of the lower animals ; .so that the 

 functions of relation, tliougli more characti'ristic of animals than of 

 |)l;nits, arc not ])ei-uliar to aiiim.als. 



It sliimld also b(^ borne in minil, that though the above groupinf 

 of tlie ]>hysinl.iiric:d functions is convenient, it is to a certain extent 



