PROTRACTED GESTATION. 915 



705. A like uncertainty exists with regard to the degree of protraction of 

 which the ordinary duration of Gestation is capable. Many obstetric prac- 

 titioners, whose experience should give much weight to their opinion, main- 

 tain that the regular period of 40 weeks is never extended by more than two 

 or three days; whilst, on the other hand, there are numerous cases on record, 

 which, if testimony is to be believed at all (and in many of these, the char- 

 acter and circumstances of the parties place them above suspicion), furnish 

 ample evidence, that Gestation may be prolonged for at least three weeks 

 beyond the regular term. 1 In one case, indeed, recorded by Liegard, 2 preg- 

 nancy was believed to have lasted 330 days. The English law fixes no pre- 

 cise limit; and the decisions which have been given in our courts, when ques- 

 tions of this kind have been raised, have been mostly formed upon the col- 

 lateral circumstances. The law of France provides that the legitimacy of a 

 child born within 300 days after the death or departure of the husband shall 

 not be questioned; and a child born after more than 300 days is not declared 

 a bastard, but its legitimacy may be contested. By the Scotch law, a child 

 is not declared a bastard, unless born after the tenth month from the death 

 or departure of the husband. Very important evidence on this subject is 

 afforded by investigations on the lower animals, which are free from many 

 sources of fallacy that attend human testimony. The observations of Tes- 

 sier, which were continued during a period of forty years, with every pre- 

 caution against inaccuracy, have furnished a body of results which seems 

 quite decisive. In the Cow, the ordinary period of gestation is about the 

 same as the Human female; but out of 577 individuals, no less than 20 

 calved beyond the 298th day, and of these, some went on to the 321st, 

 making an excess of nearly six weeks, or about one-seventh of the entire 

 period. Of 447 Mares, whose natural period of gestation is about 335 days, 

 42 foaled between the 359th and the 419th days, the greatest protraction 

 being thus 84 days, or just one-fourth of the usual term, Of 912 Sheep, 

 whose natural period is about 151 days, 96 yeaned beyond the 153d day; 

 and of these, 7 went on until the 157th day, making an excess of 6 days. 

 Of 161 Rabbits, whose natural period is about 30 days, no fewer than 25 

 littered between the 32d and the 35th ; the greatest protraction was here 

 one-sixth of the whole period, and the proportion in which there was a mani- 

 fest prolongation was also nearly one-sixth of the total number of individ- 

 uals. In the incubation of the common Hen, the duration of which must be 

 entirely determined by the rate of embryonic development, Tessier found 

 that there was not uufrequeutly a prolongation to the amount of three 

 days, or one-seventh of the whole period. In regard to Cows, the observa- 

 tions of Tessier have been confirmed by those of Earl Spencer, who has 

 published 3 a table of the period of gestation as observed in 764 individuals; 

 he considers the average period to be 284 or 285 days ; but no fewer than 

 310 calved after the 285th day; and of these, 3 went on to the 306th clay, 

 and 1 to the 313th. It is curious that among the calves born between the 

 290th and 300th days, there was a decided preponderance of males, these 

 being 74, to 32 females; whilst all of those born after the 300th day were 

 females. The additional series of observations subsequently made by Earl 

 Spencer, in regard to the constant protraction of the period in 75 cows in 

 calf by a particular bull, has been already noticed ( 762). Another series 

 of observations has been published by Mr. C. N. Bement of Albany, U. S.,* 



1 A good collection of such cases will be found in Dr. Montgomery's excellent work 

 on the Signs of Pregnancy, and in Dr. A. Taylor's Medical Jurisprudence. 



2 Gaz.'des HSpitaux, 1859. 



3 Journal of the English Agricultural Society, 1839. 



4 American Journafof the Medical Sciences, October, 1845. 



