480 GLOSSARY 



Disac'charid. [From the Lat. (lis, " twice," and saccharon, " sugar."\ 



A complex sugar which on hydrolysis yields two molecules of a 



simple sugar. 



Disaccharid Glucose Fructose 



CnH^jOn + HoO^CeHnOe + CeHiA 

 Dis'cus Prolig'erus, or germ disk. A term appUed to a mass of cells 



clinging to the ovum when it is set free from the ovary. More recent 



term is " ovarian mound." 

 Disintegra'tion. [From the Lat. dis, " twice," and integer, " entire, 



wliolc."] A breaking apart. 

 Distilla'tion. [From the Lat. distillatio, a " dripping down."] The act 



of distilling or of falling in drops. The operation of drixing off gas or 



vapor from volatile liquids or solids, by heat in a retort or still, and 



the condensation of the products as far as possible by a cool receiver. 

 Dor'sal. [From the Lat. dorsum, the " back."] Pertaining to the back, 



or posterior part, of an organ. 

 Duode'num. [From the Lat. duodeni, " twelve each."] First part 



of small intestines, so called because about twelve fingers' breadth 



in length. 

 Du'ra Ma'ter. [Lat.] The " hard mother," called dura because of its 



great resistance, and mater because it is the guardian or protector 



of the brain. The outer membrane of the brain and spinal cord. 

 Dyspnce'a. [From the Gr. dys, " difficult," and pneo, to " breathe."] 



Difficult breathing. 



Ec'toderm. [From the Gr. ektos, " outside," and denna, the " skin."] 

 The completed outer layer of cells, or outer blastodermic membrane. 

 Same as epiblast. 



Ectop'ic. [From the Gr. ek, " out of," and topos, " place."] Characterized 

 by being out of place. 



Efferent. [From the Lat. ex, " out," and fero, to " carry."] Bearing 

 or carrying outwards, as from the centre to the periphery. 



Elemen'tary. Pertaining to or of the nature of an element or elements. 



Elimina'tion. [From the Lat. e, "out of," and lirmn, liminis, a " thresh- 

 old."] The act of expelling waste matters. EUminate signifies, 

 literally, to throw out of doors. 



Em'bolus. [From the Gr. embolos, a wedge.] A portion of a blood clot 

 which has been formed in one of the larger vessels, and has afterward 

 been forced into one of the smaller vessels where it may act as a 

 wedge. 



