LSO(>.] IN THE GENERATIVE ORGANS OF A COW. 599 



modern anatomists refer them with justice to defects in the develope- 

 ment of the embryo*, assuming that the organs undergo a certain 

 transformation from a simple common type into one or other of the 

 sexes — although there are not wanting those f who have entertained 

 the view that the hermaphroditic or bisexual condition of the em- 

 bryo is the original one. Without entering into the latter hypo- 

 thesis, ably opposed by erudite authority £, we shall merely consider 

 how far the present example of malformation agrees with or bears 

 out the history of embryonic development. 



In the description of the dissection of the parts of generation it 

 was shown that the bladder entered into the vagina, and that from 

 these a common urino-genital canal continued onwards to the external 

 abdominal walls, this being the main point of resemblance to male 

 sexual organization. It is interesting therefore to find that this pre- 

 cisely corresponds to a certain stage in foetal formation. 



The researches of many distinguished enibryologists so far concur 

 as to demonstrate that, after the intestine has been occluded from 

 the umbilical vesicle with a partial dilatation of the urachus ulti- 

 mately forming the urinary bladder, there still remains a common 

 outward passage between the urinary and internal generative parts, 

 the urino-genital sinus. Afterwards in the female this sinus becomes 

 divided, and forms the narrow neck of the bladder and widish vagina, 

 while in the male the meatus urinarius continues the principal canal. 



The external organs of generation, however, are of later develop- 

 ment, and in both sexes at first identical, even in ruminants, where, 

 as Johannes Muller§ remarks, he had hoped to find an early differ- 

 ence, seeing that the sheath of the penis in the male adult opens 

 close to the umbilicus. 



According to the same talented observer, the embryos of sheep 

 have a proportionally long clitoris or penis. In the female this 

 shortens ; in the male it lengthens. In the latter, at a later period, by 

 an agglutination of the sheath, it is attached at the same time to the 

 abdominal walls, ultimately opening a short distance behind the navel. 

 The perineal cleft, from its open condition, closes, leaving traces of 

 its separation in the raphe. Later investigators, Kolliker || among 

 others, in the main substantiate these earlier observations of Midler. 



Having thus succinctly glanced at the course of development of 

 such of the urinary and genital apparatus more immediately con- 

 cerning those parts implicated in the structure of the malformation 

 in question, it remains but to consider how such history applies to 

 its abnormal condition. 



This brings us to conclude that in the earliest stage of the animal's 



* See the excellent article by Bischoff in Wagner's ' Handworterbuch der Phy- 

 siologic,' 1842, vol. i. p. 860. 



t Dr. Knox, in Brewster's ' Edinb. Journal of Science,' vol. ii. p. 322, and paper 

 reprinted from the 'London Medical Gazette' (1843), "Hermaphroditism: a 

 memoir read to the Royal Society of Edinburgh in 1827 and 1828." 



t Prof. Simpson, in the ' Cyclop, of Anat. and Physiol.' vol. ii. p. 728. 



§ Bildungsgeschichte der Genitalien aus anatomischen Untersmhungen am 

 Embryonen des Menschen und der Thiere (Dusseldorf, 1830). 



|| Entwickelung des Menschen und drr lioheren Thiere. 



