92 DR. J. W. JENKINSOX ON THE [Feb. 6, 



the wall of the allantois, and that sometimes they may be seen 

 in the connective tissue of the chorion, it has been supposed 

 that they originated in this position (Bonnet, Turner). It has 

 appai'ently escaped the notice of these observers that exactl}' 

 similar bodies are to be found ovitside the chorion, between it and 

 the wall of the uterus. 



It has ali-eady been remarked that the lumen of the utei'us is, 

 during gestation, occupied by a consideral de mass of slimy cellular 

 debris, the so-called uterine milk. The disintegrating cells com- 

 posing this viscid mass are derived in part from the cellidai- 

 secretion of the glands, in part from the extensive degeneration 

 of tracts of maternal epithelial and connective tissue ; it inchides 

 quantities of extravasated blood, and is permeated by leucocytes. 

 It is by the local accumulation of this matter that the allantoic 

 bodies are foi-med. Such aggregations may be found lying eithei- 

 freely between foetal and matei'nal tissues or enclosed in pocket- 

 like diverticula of the trophoblast (text-fig. 32, p. 91). This is the 

 first stage of their incorporation into the allantois ; and from this 

 the transition to the following steps is easy — their situation in 

 the connective tissue of the chorion, their attachment by a stalk 

 to the allantoic wall, and their libei'ation into the allantoic cavity. 



Sections show that inside and outside the allantois these bodies 

 have always the same structure — a granular coagulum containing 

 quantities of cell-detritus, with degenerating nuclei which either 

 stain veiy faintly or are broken up into dense homogeneous 

 spherules, globules of fat and small masses of glycogen, and 

 infiltrated by leucocytes. Sometimes a delicate cellular mem- 

 brane — the remains possibly of the trophoblastic pocket, or more 

 probably of the allantoic epithelium — still surrounds these bodies 

 after they have found their way into the allantoic cavity. 



Whether the allantoic bodies of the Cow are also formed in this 

 way I do not know, as I have never observed them lying in pockets 

 of the trophoblast. Bodies quite similar to those of the allantois 

 are certainly found between the trophoblast and the uterus, both 

 in and between the cotyledons ; but the remarkable thing about 

 them is that they have exactly the structuie of the degenerate 

 epithelial thickenings of the amnion, and, like these latter, are 

 impregnated with typical " envelope " crystals of calcium oxalate. 

 The bodies found in the allantois, as well as the allantoic fluid 

 itself, contain the same salt, as Lassaigne showed nearly a century 

 ago. It is possible, thei'efore, that in the Cow the disintegrating 

 epithelial thickenings of the amnion pass on the one hand into the 

 allantoic cavity, on the othei- into the uterus, and not from the 

 uterus into the allantois in the manner described for the Sheep. 



It may be noticed here that the hippomanes of the Mare are 

 also saturated with calcium oxalate. 



Lastly, the bodies found between the trophoblast and the 

 uterus of the Cow are often, especially when small, infiltrated 

 with bilirubin. With fuming nitric acid the succession of 

 colours characteristic of Gmelin's reaction is at once obtained. 



