of mortdancestor against the chief lord (that is, the sister's daughter on her uncle's  death and the half-brother's son on the same) and claimed certain land of the seisin  of a certain Ralph, their uncle. The brother's son said that he was the nearer heir  because he was the son of the said Ralph's brother, and that the niece, daughter of  the said Ralph's sister, ought not to be preferred, because he is a male and the heir of a  male and she a female and sprung from a female, and that he was therefore the nearer  heir. To which it was answered on the niece's side that he could not be the nearer heir  because he was the son of the aforesaid Ralph's brother, but his father and the aforesaid  Ralph were not brothers by the same father and mother but by one father and  different mothers, and that her mother, the niece's that is, [and Ralph] were of the  same father and mother, and the land sought was not an inheritance descending  from any ancestor but an acquisition made by the same Ralph. And because this  could not be denied it was decided that the niece was the nearer heir, because she  was born of the full sister of the same Ralph, by the same father and mother, and  the nephew, his brother's son, though male and sprung from a male, was a more  remote heir, because he stemmed from a different mother.1 Another result will  perhaps be reached in the case of a descending inheritance, according to some.2 This  case may be found in the roll of Easter and Trinity terms in the third year of king  Henry in the county of Sussex, an assise of mortdancestor [beginning] if Ralph of  Roche, against Gilbert of Aquila.34<The same may be said of a descending inheritance  if a brother dies seised; that a sister by the same father and mother is a nearer  heir to her brother's seisin than a male, his brother by the father's second wife; this  by reason of the womb.>
The exception of bastardy in an assise of mortdancestor.
 An exception of bastardy raised against a demandant or tenant in an assise of  mortdancestor destroys the assise and either turns it into a jury or transfers cognisance  to court christian, according as it is raised in one way or the other, as will be  explained more fully below [of exceptions, where bastardy is treated,]5 and there  more fully as to who may raise it and against whom. But we must see between what  persons it ought to lie in the assise of mortdancestor. It is clear that wherever the  assise lies, between whatever persons, there and between those same persons the  exception of bastardy lies. And also between persons to whom the assise does not  extend, where cosinage lies instead of an assise. But where neither the assise nor  cosinage lies there an exception of bastardy will not lie,