GLOSSARY 369 



Mammals: Vertebrate animals which suckle their young 

 after, birth. 



Meiosis: The process whereby the chromosomes of synaptic 

 paiis (in the primary oocyte or spermatocyte) are sepa- 

 rated in such a way that the resulting gametes' (eggs, 

 or sperms) receive a haploid (halved) number of un- 

 paired chromosomes', instead of the diploid (double) 

 number of paired chromosomes characteristic of the zygote 

 and the somatic cells of the species. 



Metista: Animals and plants normally multicellular and 

 having their cells differentiated into at least two distinct 

 layers or tissues — the Metazoans and Metaphytes. 



Mitosis: Typical cell-division, whose mechanism consists 

 of the spindle-fibers, and whose scope is to secure an 

 exactly equal partition of the single components of the 

 nucleus of the dividing cell between the two resultant 

 daughter-cells. 



Monism: A system of thought which holds that there is but 

 one substance, either mind (idealistic subjectivism), or 

 matter (objectivistic materialism), — or else a substance 

 that is neither mind nor matter, but is the substantial 

 ground of both. Idealistic monism regards mind as the 

 sole reality and matter as its product. Materialistic 

 monism regards matter as the sole reality and mind as its' 

 product. 



Neolithic: Pertaining to the Young-Stone Age, that is, to 

 prehistoric man of Post-glacial time. The implements of 

 the latter are of polished stone. The Young-Stone Age 

 is said to have begun about 7,000 years B.C., and to have 

 ended with the Copper Culture about 2,000 B.C. The 

 Bronze Age, which followed it; belongs to history. 



Neurone: The nerve-cell with all its processes, consisting, 

 therefore, of the nucleated cell-body, the axone or dis- 

 charging fiber, and the dentrites or receiving fibers. 



Oolites: An English term for the Jurassic, or middle system 

 of the Mesozoic group of fossiliferous rocks. 



Ontogeny: The embryological development of the indi- 

 vidual. 



