I So GLOSSARY. 



Myosin'ogen (Gr. mus, muscle; gennao, I produce). A 

 proteid substance occurring in muscle plasma and con- 

 cerned in the formation of rnyosin. 



Myo'sis (Gr. muo, to close). Contracted condition of pupil. 



Na'sion (L. nastis, the nose). The nasal point of skull. . 



Natural currents. Certain electrical currents which are 

 supposed to exist in muscle or nerve tissue when at rest. 



Negative variation. Changes in the natural nerve or muscle 

 currents which occur during contraction. 



Neu'raJ. met'amere. Term applied to a spinal segment. 



Nodes of Ranvier. Constrictions in a nerve due to interrup- 

 tions in the white substance of Schwann. 



Non-polarizable electrode. An electric terminal which is 

 incapable of setting up secondary currents on application 

 to living structures. 



Nucleus of Pander. A mass of white yolk seen in fowl's 



egg- 



Nystag'mus (Gr. nustazo, to be sleepy). Involuntary lateral 

 movements of the eyeballs. 



Obelion (Gr. obelaia, an arrow). A point in the skull opposite 



parietal foramen. 

 Oncome'ter (Gr. ogkos, a tumour ; metron, a measure). An 



apparatus for estimating the variations in bulk of any 



organ. 

 Onto'geny (Gr. on, gen.ontos, existence ; genesis, creation). 



The history of the development of single beings. 

 Oph'rion (Gr. ophrus, the eye-brow). The supraorbital point 



of skull. 

 Opi'sthion (Gr. opisthen, behind). The centre of posterior 



margin of foramen magnum. 

 Ooph'eron (Gr. don, egg ; phoro, I bear). The ovarian 



parenchyma. 

 Or'thopnaea (Gr. orthos, force ; pneuma, air). Breathing in 



semirecumbent posture. 

 Os centra'le. A carpal bone of the lower Vertebrates, but 



in man is generally fused with scaphoid, or suppressed. 

 Os interme'dium. A carpal bone, represented in man by the 



semilunar. 



