AND THOSE OF CERTAIN OTHER MAMMALIA. 79 



wall and the umbilical vein, which is not rare in mammalia \ was 

 very plainly demonstrable. 



The placenta proper has assumed the ' flocculent ' appearance 

 which prolonged maceration, whether in weak spirits or in any 

 other such menstruum, will confer on any placenta, however 

 | cellulo vascular ' or ' spongy,' in the normal condition. Still to 

 the apices of its villus-bearing trees, shreds of the lamina are in 

 several instances left adhering, especially in the angle between 

 the chorionic upgrowth and the uterine aspect of the placenta. 

 The layer of tissue adherent to the utero-placental area possessed 

 histological characters quite distinct from those of the muscular 

 coat it overlay. The circular muscular coat is easily separable from 

 the longitudinal. 



The lamina of tissue intermediate between the placenta and the 

 utero-placental area I would propose (without any reference to the 

 etymological meaning of the word ' serotina,' or to the now ex- 

 ploded theory which the word was intended to bring before the 

 mind) to call ' deciduous serotina ; the utero-placental mucous area 

 I would call ' non- deciduous serotina; and the spongy structure 

 made up of villi and umbilical vessels, and, in all placental mam- 

 mals (except Cetacea, Artiodactyles, and Perissodactyles, and possibly 

 Bruta), of more or less maternal structure inextricably intermixed as 

 well, I would call 'placenta/ The word 'after-birth' includes 

 ' placenta ' and f deciduous serotina/ both usually, though not in- 

 variably, coming away together. 



Owing to errors of observation, the name 'decidua serotina' has 

 been applied to the structure I would call ' non-deciduous serotina,' 

 as well as to that to which Dr. Priestley 2 , like myself, would limit it. 

 It is called ' parietal decidua ' by Professor Goodsir 3 , and f caduque 

 utero-placentaire ' by M. Robin 4 . And in an account of it given 

 by Professor Kolliker, I find him speaking of it in the human 

 subject as ' eine zusammenhangende Haut wenn er gut erhalten 

 ist V It is sometimes called ' placenta materna ;' but this 

 phrase is applied to the maternal element of the ' placenta ' also, 



1 Rathke and Coste, cit. Kolliker, ' Entwickelungsgeschichte,' p. 420. 



2 ' On the Development of the Gravid Uterus,' pp. 32 and 48, i860. 



3 'Anatomical and Pathological Observations/ 1845, p. 60, pi. 3, fig. 6. 



4 'Mem. Acad. Imp. Me*d. Paris,' 1861, torn. xxvi. pp. 131 and 141, where there is 

 a disquisition on its histology. See also Cazeau, 'Traite* des Accouchements,' 1856, 

 pp. 192 and 202. 5 I.e. pp. 145 and 158. 



