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GLOSSARY 



Va-gi'na (L. sheath). The canal in the fe- 

 male reproductive tract which receives 

 the penis in mating. 



Va'gus (L. wandering). The tenth cranial 

 nerve. 



Va-ri-a'tion (L. variare, to change). Differ- 

 ence in structure or function exhibited 

 by individuals of the same species. 



Va-ri'e-ty (L. varietas, difference). One of 

 the sub-divisions of the species. 



Vas de'fer-ens (L. vessel; L. carrying 

 down). The tube or duct which con- 

 veys sperms away from the testis. 



Va'sa ef'fer-en"ti-a (L. vessels; L. ejferens, 

 bringing out ) . Small ducts which carry 

 sperms from the testis to the epididy- 

 mis in higher vertebrates. 



Vas'cu-lar (L. vasctdum, little vessel). Per- 

 taining to vessels. 



Vein (L. vena, vein). A blood vessel that 

 carries blood to the heart. 



Ven'tral (L. venter, belly). The lower sur- 

 face, opposite to dorsal. 



Ven'tri-cle (L. ventrictihis, little belly). A 

 lower muscular pumping chamber of 

 the heart, also a brain cavity. 



Ver'mi-form ap-pen'dix (L. vermis, worm; 

 forma, form; ad, to; pendo, hand). A 

 small, blind pouch projecting from the 

 caecum in some mammals. 



Ver'te-bral corumn (L. vertere, to turn). 

 See Spinal column. 



Ver'te-brate (L. vertebrattis) . Animal with 

 a backbone. 



Ves-tig'i-al ( L. vestigium, footstep ) . A rudi- 

 mentary or degenerate structure which 

 at one time was functional or better 

 developed. 



Vil'lus ( L. villus, hair ) . A very small, finger- 

 like projection, especially found in the 

 vertebrate intestinal lining for increas- 

 ing absorption. 



Vi'rus (L. slimy liquid, poison). The sim- 

 plest living organism composed almost 

 entirely of nucleoprotein. They are 

 capable of reproduction only within 

 cells and are visible only under the 

 electron microscope. 



Vis'cer-a (L. internal organs). Internal or- 

 gans of the body cavity. 



Vi'ta-min (L. vita, life; M.E. amine, a 

 chemical radical). A general term for 

 a number of unrelated organic sub- 

 stances found in many foods and nec- 

 essary, in small quantities, for normal 

 metabolic activity. 



Vi-tel'line (L. vitellus, yolk). Pertaining to 

 egg yolk. 



Vi-vip'a-rous (L. vivus, alive; parere, to 

 bear). Producing young that receive 

 nourishment for their development 

 from the uterine wall of the mother. 



Warm'-blood'ed. Animals possessing a tem- 

 perature regulating device which en- 

 ables them to maintain a constant body 

 temperature. 



Zo'o-ge-og"ra-phy (Gr. zoion, animal; ge, 

 earth; graphein, to write). A branch of 

 zoology dealing with the geographic 

 distribution of animals. 



Zy'gote (Gr. zygotes, united). The ferti- 

 lized egg. 



