GLOSSARY 



Accessory chro'-mo-some. An odd chromosome which is found 

 in only half of the spermatozoa of certain animals; see 

 "sex-chromosome." 



A-chro'-ma-tin. The non-staining substance of the nucleus 

 as contrasted with the chromatin. 



A-chon'-dro-pla-sy. A condition in which the long bones 

 cease to grow in length at an early age thus producing a 

 dwarf with large body and head but short limbs. 



Acquired Character. A character, the differential cause of 

 which is environmental. 



Alternative Inheritance. Galton's term for a doubtful kind 

 of inheritance in which all characters are derived from one 

 parent. In present use, Mendelian inheritance. 



Am'-ni-on. One of the embryonic membranes of higher verte- 

 brates. 



Am-phi-ox'-us. One of the lowest and simplest animals hav- 

 ing a notochord (backbone). 



An-en-ceph'-a-ly. The condition of a brainless monster. 



Animal pole. That pole of an egg at which the polar bodies 

 are formed. 



An'-la-ge. The embryonic basis of any developed part. 



A-or'-ta. The great artery arising from the heart. 



Ar'-chi-plasm. The deeply staining plasm surrounding the 

 centrosome. 



As'-ca-ris. A genus of round worms which are intestinal 

 parasites. 



As'-ca-ris meg-a-lo-ceph'-a-la. A parasite in the intestine of 

 the horse. 



As-cid'-i-an. A "sea-squirt"; one of the lowest types having 

 a notochord, or elementary backbone. 



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