THE PELVIC CANAL 55 



pasture in spring a swaying walk behind is noticeable for 

 quite some time, wliicli gradually improves until the animal is 

 again served and impregnated. The sacrum stays in its 

 abnormal position, as the wings are fastened by new connec- 

 tive tissue, which gradually becomes tendinous. In such 

 animals the height of the pelvic inlet is decidedly decreased 

 (Stockfleth). 



In the year 1894 such a cow was presented here at the 

 ambulatory clinic. She was pregnant for seven months and 

 the sacrum had sunk completely between the internal iliac 

 angles. On examination, the height of the pelvic inlet was 

 12 cm., while in the normal state it should have been from 19 

 to 20 cm. 



For the owner's interest I considered it best to await the 

 normal end of pregnancy, and to render assistance during 

 parturition by performing a partial or complete embryotomy. 

 The reasons inducing me to do so were : (a) milk production is 

 better when the animal does the regular time than if abortion 

 takes place ; (b) the risks connected with artificial abortion ; 

 (c) the little danger of embryotomy. 



Two months later the cow was again examined during 

 labor pains, and since the circumference of the calf prevented 

 its extraction in toto, embryotomy was performed. After re- 

 moving the anterior limbs subcutaneously, the head just went 

 through the inlet. The operation was finished in the ordinary 

 manner. Four days later the cow went out to grass. 



4. Indications furnished by pelvimetry during the act of 

 parturition. 



This refers equally to extractions in normal and abnormal 

 presentations. The knowledge of the pelvic diameters enables 

 the operator to compare the dimensions of the calf with the 

 greatest pelvic diameter and thus make birth easier. 



I shall mention here an example. It often happens that 

 when one half of the calf is born (head, neck and anterior 

 limbs), the posterior extremity cannot glide through the inlet, 

 as the calf's sacrum catches the mother's sacrum ; here slight 

 torsion of the calf suffices to extract it with but little exertion. 



