PLACENTAL 



1108 



PLAGIOCEPHALY 



in which the villi are at first diffuse, but ultimately 

 become restricted to the ventral surface. P. multi- 

 loba, a placenta consisting of more than three lobes in 

 an animal in which the organ normally is one-lobed. 

 P., Non-deciduate, the simplest form of placenta, in 

 which the papilla-like elevations of the chorion fit into 

 corresponding depressions in the uterus, and in 

 which the chorion can be withdrawn from the placenta 

 at birth. The Artiodactyla, Perissodactyla, Sirenia, 

 Cetacea, Lemuroidea, and some Edentata (Squamata) 

 have a non-deciduate placenta. In some of them the 

 villi are more or less branched and complicated, 

 at times interlocking so closely that the parts of the 

 epithelium of the maternal cotyledons may be carried 

 away at birth. P. obsoleta, in a twin pregnancy the 

 condition in which the two placentae are entirely dis- 





Placenta and Membranes (Stripped upward). 



tinct and separate, P. panduriformis , one shaped 

 like a violin. P., Polycotyledonary, P., Polycoty- 

 ledonous, a placenta such as is seen in ruminants, in 

 which the chorionic villi are collected in a number 

 of large separate tufts, the latter dipping into cor- 

 responding crypts in the uterine mucosa. P. praevia, 

 a term applied to a placenta when it is fixed to 

 that part of the uterine wall that becomes stretched 

 as labor advances, so that it precedes the advance of 

 the presenting part of the fetus. P., Retained, one 

 not expelled by the uterus after labor. P. sanguinis. 

 See Blood-clot. P., Secondary Discoid. See P., 

 Metadiscoid. P. spuria. See Placenta succenturiata. 

 P., Subsidiary, a distinct and separate lobe in addi- 

 tion to the usual placental mass ; such lobes are called 

 Placenta: succenturiata:. P. succenturiata, an acces- 

 sory growth to the placenta. When this does not act 

 as true placental tissue it is termed Placenta spuria. 

 P. tripartita, an anomaly of the placenta in which 

 there are three portions of that organ. P., Triple, 

 the united placentae of a triple gestation. P., Twin. 

 Synonym of P. duplex. P. uterina, the rough 

 cotyledonous or uterine surface of the placenta derived 

 from the decidua serotina. P., Velamentous, one 

 in which the cord is inserted between the layers of 

 the fetal membranes, presenting a broad surface 

 of attachment in place of the normal round inser- 

 tion. P., Villous. See P., Disseminated, P., 

 Zonary, a placenta which occupies a broad band 

 around the chorion ; it is found in the Carnivora , 

 Jfyrax, Elepltas, and in the Tiibulidentata among the 

 Edentata. Same as P. , Annular. 

 Placental (pla- sen' -tal)[ placenta, k?mkovc , a. fial cake]. 



Pertaining to the placenta. P. Dystocia, difficult 

 birth of the placenta. P. Murmur. Same as P. 

 Souffle. P. Souffle, a sound erroneously attributed 

 to the circulation of blood in the placenta. 



Placentalia (pla-sen-ta' -le-ah) [placenta, -/,< 



cake]. Mammals in which the fetus is nourished 

 through the medium of a placenta. 



Placentary (pla'-sen-ta-re) [placenta, Tr/.aKovc, a flat 

 cake]. Pertaining to the placenta. 



Placentate (pla' ' -sen-tat)[placenta, 7rZa/coir, a placenta] 

 Having a placenta. 



Placentation (pla-sen-ta' -shun) [placenta, t-a, 



placenta] . In biology : (a) the process of attachment 

 of the embryo or fetus to the uterus ; {I/) the type of pla- 

 centa or the manner in which it is constructed ; the 

 arrangement of the seeds in the pericarp or the ar- 

 rangement of the placenta itself. 



Placentiferous (pla-sen-tif '' '-er-us) [placenta, r 



placenta ; ferre, to bear]. In biology, bearing a pla- 

 centa. 



Placentiform [pla - sen'- tip- orni) [placenta, - 

 placenta ; forma, form]. In biology, resembling a 

 placenta; discoid with biconcave surfaces. 



Placentigerous {pla-sen-tif -er-us). Same as Placen- 

 tiferous. 



Placentitis (pla-sen-ti'-tis) [placenta, irlaicovc, a flat 

 cake; trie, inflammation]. Inflammation of the pla- 

 centa. P. decidualis, placentitis secondary to in- 

 flammation of the decidua. 



Placentoid (pla-sen'-toid) [placenta, Tr/anoir, a flat 

 cake ; ehhg , like]. Resembling a placenta. 



Placentula (pla-sen'-tu-la/i) [dim. of placenta, n'/a- 

 kovc, placenta]. A small placenta. 



Placoderm, Placodermal (plak'-o-derm, plak-o-ier'- 

 mal) [tv?£!-, a plate; deppa, skin]. In bii 

 having the skin covered with broad flat plate:-. 

 fish. 



Placoid (plak'-oid) [n/.a!;, (tv7mk-), a tablet; 

 form]. In biology, plate-like; applied to the 

 skeletal pieces of certain fishes. 



Placula (plah'-u-lah) [tt?M, a tablet, plate : //.. 

 ul<e\. In biology, a, little plate; applied to ci 

 discoid embryos, which consist of a plate of clei 

 cells. 



Placular (plak'-u-lar) [jr/Wf, a plate]. Plate-like;! 

 like a placula. 



Placulate (plak'-u-ldt) [n?.a%, a plate]. Havii 

 form of a placule. 



Placuntechos (plak-unt-ek'-os) [nXanovr, a flat Ctb 

 tjxoc, echo]. The uterine souffle. 



Placuntitis (plak-un-ti'-tis). Synonym of Pla<; : 



Pladaroma (plad-ar-o'-mah) [n'kaddpuna, \\< 

 softness: pi. , Pladaromata']. A soft wart, or I 

 of the eyelid. 



Pladarosis (plad-ar-o'-sis) [Trlafiapdc, soft], Syi 

 of Pladaroma. 



Plaga (pla'-gah) [~h/y?/, stroke ://., Plaga\ Woun 

 plague. In biology, a stripe or streak. P. ignis. 

 Anthrax. P. scapularis. Same as Parapsis. 



Plagiobolia (pla-je-o-bol'-e-ah) [irlayioc, oblique J ^ 

 If iv, to throw]. Imperfect or indirect en 

 spermatic fluid into the vagina. 



Plagiocephalia (pla-je-o-sef-a'-le-ah). S 

 cephaly. 



Plagiocephalic (pla-je-o-sef-al'-ik) [rr/iiyr 



twisted; kf4<i?S/, head]. Exhibiting or dependent 

 plagiocephaly. 



Plagiocephalous (pla -je ■ o ■ sef- al- us). F 

 Plagiocephalic. 



Plagiocephaly (pla-je-o-sef'-al-e) [irMyw, sideWM 

 slanting, oblique ; Ke<f>a?j/, head]. In biolog 

 formation of the head, produced by the cl< 



