436 THE HUMAN SPECIES 



The character of the pains during labour is of supreme im- 

 portance both in human beings and animals. All diminution 

 in their strength, or in the extent to which they affect the 

 uterine tissue, is more or less a hindrance to the course of par- 

 turition. Excessive or tetanic contractions are especially dis- 

 astrous when parturition cannot proceed owing to a faulty 

 position or attitude of the foetus, and the accoucheur is prevented 

 from seizing it owing to the extreme pressure. If the condition 

 is not relieved lacerations and other important complications 

 may ensue. M. Schmidt reports two cases of laceration of the 

 uterus in lionesses in the Zoological Gardens at Grenoble and 

 Frankfort-on-the-Main. Abnormal contractions of certain sec- 

 tions of the uterus also tend seriously to prolong parturition both 

 in human beings and animals, though not to such a dangerous 

 extent. These contractions occur where the musculature is 

 circularly arranged as at the internal and external os. The 

 delay caused by weak pains can be still more easily understood, 

 whether involving the whole uterus or only a portion thereof. 

 Both in human beings and animals parturition cannot proceed 

 when the musculature is tired out by long and fruitless pains, 

 especially when the position of the foetus is faulty. 



Although in the various factors causing prolonged parturi- 

 tion which have hitherto been described there is a general re- 

 semblance between human beings and animals, a marked differ- 

 ence will be noted when we consider the various malpositions of 

 the foetus in utero : although these malpositions may in both 

 cases be classified as head presentations, breech presentations 

 and transverse presentations. The main difference between 

 human beings and animals is concerned with cephalic presenta- 

 tions, and is due to the different shape of the skull. In human 

 beings the calvarium is especially developed, and this presents 

 most frequently ; when the pelvis is normal this presentation has 

 the best prognosis, though it is not quite so good when the 

 head is placed obliquely, when the occiput is rotated backwards, 

 or where the deeper parts are transverse. Face presentations, 

 on the other hand, are among the most unfavourable, as labour 

 is prolonged and the child's life threatened. In animals, on the 

 other hand, face presentations are normal, and presentation of the 

 calvarium one of the worst complications of labour. In human 



