EMBOITMENT 



419 



EMBRYO 



Emboitment (on(g)-bwat' '-mom g)) [OF., emboister, to 

 inclose, as in a box]. In biology, Bonnet's doctrine 

 that each germ includes the germs of all generations 

 that shall succeed it. 



Embolemia (em-bol-e'-me-ah) [f« ; 3o/.oc, thrown in; 

 atua, blood]. A state of the blood in which it is 

 said that emboli are readily formed. 



Embolic {em-bol'-ik) [e/*/3o/oc, thrown in]. Relating 

 to, associated with, or caused by an embolus. 



Emboliform {em-bol' '-if-orni) [e/uj3o?.oc, an embolus ; 

 forma, form]. Resembling an embolus. 



Embolism {em'-bo-lizm) \_ifi3o/.oq, an embolus]. The 

 obstruction of an artery or capillary, usually by a 

 blood-clot or embolus, brought from another point by 

 the blood-current. These emboli may be fragments 

 of vegetation from the valves of the heart, clots from 

 a thrombosis or aneurysm, or fragments of atheroma- 

 tous tissue. Around the seat of an embolus thrombo- 

 sis occurs with the production of an infarct, q. v. E., 

 Air, by a bubble of air. E., Capillary, obstruction 

 of capillaries by micrococci. This occurs in pyemia. 

 E., Fat, the entrance into the circulation of fluid fat 

 after extensive injuries. Death often follows. The 

 symptoms are restlessness, anxiety, slight dyspnea, 

 accelerated breathing, quickening of the pulse ; cya- 

 nosis, delirium, and insomnia, followed by coma, are 

 graver symptoms. The temperature may remain sub- 

 normal or it may rise. E., Infective, the emboli are 

 metastatic. This occurs in pyemia and ulcerative 

 endocarditis. E., Multiple, numerous small emboli. 

 E., Paradoxical, embolism of an artery by a venous 

 thrombus, as may occur in a patulous foramen ovale. 

 E., Pyemic. See £., Infective. E., Retinal, occur- 

 ring in the arteria centralis retinae, followed by sudden 

 loss of vision. E., Venous, occurring in veins, espe- 

 cially of the lungs and liver. 



Emboloid {em' '-bo-loid) [ifipo/.og, an embolus; eldoq, 

 likeness]. Resembling an embolus. 



Embololalia {em-bo-lo-la' -le-ah) [eu/fo/.oc, a thing 

 thrown in ; 7,a~/.ia, talk]. The morbid intercalation of 

 words, often meaningless, into the speech. 



Embolophrasia [em-bo-lo-fra' -ze-ah) \iufo~/.oq, inser- 

 tion ; tbpaaig, speech]. Embololalia. 



Embolus iem'-bo-lus) [eftSo/.og; ev, in; (ia'AAeiv, to 

 throw]. I. A clot of blood, or plug of other material, 

 brought by the blood-current from a distant artery, 

 and forming an obstruction at its place of lodgment. 

 2. Wilder' s term for the nucleus emboliformis. 



Emboly (em'-bo-le) \iu3o'/ij, insertion]. In embryolo- 

 gy, the process of invagination that gives rise to a gas- 

 trula from a blastosphere or vesicular morula. 



Embrocation (em-lno-ka'-sJiun) [hiiftpexeLv, to soak 

 in]. A fluid external application for some injured or 

 diseased part. 



Embryectomy (em-bre-ek 1 '-to-me) \jtfi(ipvm>, embryo ; 

 lurniiTj, a cutting out]. The surgical removal of the 

 embryo in extra-uterine pregnancy. 



Embryo [cm'-bre-d) \ififipvav\. The ovum and the pro- 

 duct of conception up to the fourth month of pregnancy ; 

 the fertilized germ of an animal. Applied in botany 

 to the rudimentary plant within the seed. E.-sac. 

 In biology, (a) the cell in the nucleus of the ovule 

 of flowering-plants, that contains the germinal vesicles 

 and finally the embryo ; (b) the protoconch or primi- 

 tive shell of certain cephalopods. 



II 



Scheme of a Longitudinal Section of an Early 



Embryo. 



E. Epiblast. m. Mesoblast. e. Hypoblast. 



Scheme of the Formation of the Head- and Tail-Folds. 



r. Head-fold. D. Anterior extremity of the future intestinal 



.tract. S. Tail-fold, first rudiment of the cavity of the rectum. 



Scheme of a Longitudinal Section through an Embryo 



after the Formation of the Head- and Tail-Folds. 

 Ao. Omphalo-mesenteric arteries. Vo Omphalo-mesenteric 

 veins, a. Position of the allantois. A. Amniotic fold. 



Scheme of a Longitudinal Section through a Human 

 Ovum. 



Z. Zona pellucida. S. Serous cavity, r. Union of the amniotic 

 folds A. Cavity of the amnion, a. Allantois. X. Umbilical 

 vesicle, m. Mesoblast. h. Heart. U. Primitive intestine. 



Scheme of Human Embryo, with the Visceral Arches 

 still Persistent. 



A. Amnion. V. Fore-brain. M. Mid-brain. H. Hind-brain. 

 N. After-brain. U. Primitive vertebrae, a. Eye. p. Nasal 

 pit. S. Frontal process jr. Internal nasal process, n. Ex- 

 ternal nasal process, r. Superior maxillary' process of the 

 first visceral arch, i, 2, 3, and 4 The four visceral arches, 

 with the visceral clefts between them. o. Auditory vesicle, 

 h. Heart, with e. primitive aorta, which divides into the five 

 aortic arches f. Descending aorta, om. Omphalic-mesen- 

 teric artery, b. The omphalo-mesenteric arteries of the um- 

 bilical vesicle, c. Omphalo-mesenteric vein. L. Liver with 

 venae advehentes and revehentes. D. Intestine, f. Inferior 

 cava. T. Coccyx, all Allantois, with z, one umbilical 

 artery; and x, an umbilical vein. 



