MANNER OF DEVELOPMENT. 43 



In various mammals the uterus graduates from a double 

 organ with two distinct orifices and two passages, as in the 

 marsupials, into a single organ, which is in no way double 

 except from having a slight internal fold, as in the higher 

 apes and man. The rodents exhibit a perfect series of gra- 

 dations between these two extreme states. In all mammals 

 the uterus is developed from two simple primitive tubes, 

 the inferior portions of which form the eornua; and it is, iw. 

 the words of Dr. Farre, "by the coalescence of the two 

 cornua at their lower extremities that the body of the uterus 

 is formed in man; while in those animals in which no mid- 

 dle portion or body exists, the cornua remain ununited. As 

 the development of the uterus proceeds, the two cornua be- 

 come gradually shorter, until at length they are lost, or, as 

 it were, absorbed into the body of the uterus." The angles 

 of the uterus are still produced into cornua, even in ani- 

 mals as high up in the scale as the lower apes and lemurs. 



Now in women, anomalous cases are not very infrequent, 

 in which the mature uterus is furnished with cornua, or is 

 partially divided into two organs; and such cases, according 

 to Owen, repeat " the grade of concentrative development," 

 attained by certain rodents. Here perhaps we have an in- 

 stance of a simple arrest of embryonic development, with 

 subsequent growth and perfect functional development; for 

 either side of the partially double uterus is capable of per- 

 forming the proper office of gestation. In other and rarer 

 cases, two distinct uterine cavities are formed, each having 

 its proper orifice and passage.* No such stage is passed 

 through during the ordinary development of the embryo ; 

 and it is difficult to believe, though perhaps not impossible, 

 that the two simple, minute, primitive tubes should know 

 how (if such an expression may be used) to grow into two 

 distinct uteri, each with a well-constructed orifice and pas- 

 sage, and each furnished with numerous muscles, nerves, 

 glands and vessels, if they had not formerly passed through 

 a similar course of development, as in the case of existing 

 marsupials. No one will pretend that so perfect a struct- 

 ure as the abnormal double uterus in woman could be the 

 result of mere chance. But the principal of reversion, by 



* See Dr. A. Farre's well-known article in the " Cyclopaedia of 

 Anatomy and Physiology," vol. v, 1859, p. 642. Owen, "Anatomy 

 of Vertebrates," vol. iii, 1868, p. 687. Prof. Turner, in " Edinburgh 

 Medical Journal," Feb., 1865- 



