GLOSSARY 455 



uvula. The median posterior pendulous process of the soft palate. 



vagina. The tubular passage from the uterus to the outside. 



valvulae conniventes. Transverse folds of the lining of the small intestine. 



varicose. Tortuous and swollen. 



vas deferens. The efferent duct of the testis. 



vasa efferentia. The ductules which connect the testis with the ductus (vas) deferens. 



vasopressin. An hormone secreted by the posterior lobe of the pituitary, which 



stimulates contraction of smooth muscle, 

 veliger. The trochophore larva of molluscs. 



ventricle. A small cavity such as is found in the brain and heart, 

 vermis. The median lobe of the cerebellum. 

 vemix caseosa. The waxy covering of the fetal skin. 

 vesicle. A liquid-filled sac or cavity. 



vitamin. A food substance of unknown composition necessary for growth and health, 

 vitelline. Pertaining to vitellus or yolk. 



vitreous humor. The translucent semisolid substance between retina and lens, 

 viviparous. Giving birth to living young. 

 volvox. A genus of flagellate algae. 



Wharton's duct. The duct of the submaxillary. 

 Wirsung's duct. The duct of the pancreas. 



Wolffian ducts. The ducts of the mesonephros. In the male the ductus deferentes. 

 Wolffian folds or ridges. Paired longitudinal ridges of the embryo from which the 

 paired appendages are differentiated. 



xiphistemum. The xiphoid cartilage of the sternum. 



zygapophysis. An articular process of a vertebra. 

 zygomatic bone. The malar bone, 

 zymogen. An enzyme-forming substance. 



