GLOSSARY 513 



Tek-a-tol'-o-gt. The science which deals with monstrous or 

 abnormal forms. 



Tet'-hads. Bivalent chromosomes which appear 4i-parted in 

 the maturation divisions. 



To-Tip'-o-TENCE. The capacity of a cleavage cell to give rise 

 to a whole animal. 



Tox'-iN. A poisonous substance particularly such as is pro- 

 duced by bacteria. 



Tri-hy'-brid. The offspring of parents differing *in three char- 

 acters. 



Troph'-o-blast. The outer layer of the blastodermic vesicle 

 of a manmial. 



Tko'-pisms. Automatic movements of organisms toward or 

 away from a source of stimulus. 



Unit Character. A character which is inherited as a whole 

 and cannot be sub-divided. 



Vegetative pole. The pole of an egg opposite the polar 

 bodies. 



Vil'-li. Processes which grow out from the embryonic mem- 

 branes of a mammal and connect it to the walls of the 

 uterus. 



Vi-tel'-i.ine membrane. A delicate membrane around an egg 

 secreted by the egg itself. 



Viv-i-par'-i-tt. Young brought forth "alive," in an advanced 

 stage of development. 



Zt'-gote. The product of the union of male and female sex 

 cells. 



