82 OBSTETRICAL PHYSIOLOGY. 



membrane of the uterus from which the deciduous maternal parts of the 

 placenta grow, and which have been already described as the " maternal 

 cotyledons " or " placentae ; " into these latter the foetal processes are 

 received. The maternal cotyledons are nothing more, as has been 

 stated, than appendages or thickened points of the mucous membrane, 

 whose utricular follicles, more numerous than elsewhere, have become 

 enormously enlarged, and crypts have been formed. They are perma- 

 nent, as before conception they are certainly present on the inner sur- 

 face of the uterus, and traces of them may be already found in the fcetus 

 of four or five months ; observation also appears to have demonstrated 

 that they may be increased in number, or regenerated, when accidental 

 circumstances render those in existence insufficient* They have been 

 discovered in the foetus in process of formation, and regularly disposed, 

 beside the ordinary cotyledons. 



When gestation has commenced, the surface of the maternal caruncles, 

 previously smooth, becomes convex, and is covered ^yith reticulate pro- 

 cesses which border the crypts, and give it a finely cribbled appearance. 



* In the Jdurnalde Mid VHerhiaire de Lyon, M. Strebel, of La Tour, Switzerland, gives an instance 

 in which there ^yas absence of the uterine cotyledons in a Cow, and the placenta was like that of the 

 Mare. Conception took place, gestation went on favorably, and parturition was normal. 



Chauveau's experiments have proved, that after all these placentulse have been extirpated from the 

 uterus of the pregnant Cow, sterility does not necessarily follow ; but if, on the contrary, the animal sur- 

 vives the operation, it is still capable of breeding. In such circumstances, accessory cotyledons are de- 

 veloped upon the surface of the uterine mucous membrane, where previously none existed. Chauveau 

 has also stated, in the same journal for 185 1, that during pregnancy the number of cotyledons is in- 

 creased ; and Colin, in his Physiologie Comparee, makes a similar statement. Professor Franck, of 

 Munich, in his dissections of the gravid uterus of bovines, has found, in a large number of instances, a 

 more or less abundant quantity of accessory caruncles (karunkeht) on the mucous membrane, and which 

 had no corresponding relations with the chorion. In one instance the ordinary cotyledons were entirely 

 absent in an unimpregnated cornu, and in their stead were thousands of the accessory processes grouped 

 together in small clusters. The whole of the lining membrane of this cornu had a peculiar mossy or vel- 

 vety appearance. In a number of instances Franck has observed, in the immediate neighborhood of the 

 OS uteri, where cotyledons proper were absent, groups of the so-called accessory cotyledons, in their form 

 r&\)X&%^r\.\AW%7i placenta preevia. Certainly, this VmA oi placenta pravia in cattle has not the disadvan- 

 tages it offers in woman ; for although a premature delivery may occur, a sufficiency of the placenta 

 always remains to maintain the nourishment of the fcetus. Serious hjemorrhage is likewise little to be 

 apprehended in such cases ; and even the disconnection between the placenta foetalis and the placenta 

 uterina in the Cow, causes no injury. This is not the case with the human female and the Bitch. Small 

 haemorrhagic streaks at the summit of the finer tufts, or on their upper surface, are often noticed in the 

 uterus of Cows which have been slaughtered and bled. Birnbaum attributed these streaks to a plethora 

 ex vacuo {Untersuchu7ige7i iiber de7t Ban der Eih'dute der Saugethiere, p. 90). 



The accessory placentulae are, both in shape and situation, as well as in development, different from the 

 cotyledons propei; for while the latter, and of course also the foetal cotyledons, are arranged in four 

 regular rows, in the gravid uterus, through the rapid increase of the amnion towards the poles of the 

 ovum, they lie somewhat closely together, and the accessory processes are placed between these rows in 

 an irregular manner. In their highest development, the latter are so disposed as to constitute a variable- 

 sized felt-like patch ; the largest and widest are usually observed behind the ordinary cotyledons, and 

 their form is very irregular, but normal. As a rule, the largest are not so big as a walnut, and they are 

 widest at their base. In structure they resemble the ordinary cotyledons, their blood-vessels being ar- 

 ranged in the same manner, while they are covered externally by a sheath of epithelium. In the early 

 period of pregnancy — about the second or third month— they are found in largest number on the entire 

 upper surface of the chorion, also likewise on the parts between the ordinary cotyledons and the finest 

 caruncles. It may here be mentioned that the ovum of the Cow, in the first week of pregnancy, is 

 smooth. Franck has never been able to discover the vascular semi-detached caruncles which are after- 

 wards developed through the prolongation of the blood-vessels ; though they are found in the canine 

 species. He has, however, observed definitely-formed vascular chorion-cotyledons between the fourth 

 and sixth weeks of pregnancy. The interposed cotyledons observed by Franck have been noticed by 

 other anatomists. Birnbaum mentions them, but he is in error with regard to their development, inas- 

 much as he believed that they arose from the uterine glands, which is certainly not the case. The chorial 

 tufts penetrate the uterine mucosa by four digitations, fixing themselves in the so-called simple follicles, 

 according to Franck {Deutsche Zeitschri/t fur T/iiermedicin). This excellent authority also points out, 

 with regard to this circumstance, that in the vicinity of the uterine glands there are found small follicles 

 which are nearly always unobserved. The connection between these chorial tutts and the uterine mucosa 

 is extremely slight. 



At a later period of pregnancy, there appear other caruncles tn the torm ot toeta/ tutts ana cotyledons, 

 which the previously developed and prominent maternal cotyledons and caruncles lie opposite to and in 

 contact with. The reason tor this tact is to be sought tor in the circumstance, that the tcetal caruncles 

 pass into the most developed uterine cotyledons, and in consequence bring the larger tutts ot the allantois 

 into contact with the opposite parts ot the chorion. The intermediate caruncles become entirely wasted. 

 Nevertheless, with isolated tufts, sometimes in a great many, we find an increased development, wllich 

 gives rise in the corresponding uterine mucosa to a similar formation, and a close co-aptation, or even an 

 inter-penetration ot these accessory tcetal and maternal cotyledons. 



