English to Japanese Law/Patents Law: Contract(s) land sale contract

I have a land contract, that was translated from Spanish into English, that I have been tasked with translating into Japanese. I have both the Spanish and English copies and it seems like the English is a very direct translation. The text that I am having trouble with is in the "Statements" section. It says:

"FIRST: The seller states:.......D) To be the legitimate and sole owner of (i) the Plot of Land denominated "XXX", (ii) the Fraction letter "B" of the Plot of Land denominated "YYY" and (iii) the Fraction IV of the plot of land denominated "ZZZ"..."

I was completely confused by this until I came to the next page which has a chart listing the lots to be sold and their sizes. After Lots 1-4, it lists (untranslated) "Faccion 1 Lote 5", "Fracion 1 Lote 8" and then "Fracion 3 Lote YYY". I assume this to mean that Fraction B above and Fraccion 3 here are the same thing, since the "YYY" is the same plot name.

When I tried to find an English equivalent term I found a description of "fractional lots" on the following page. (pg 161-162 if the link doesn't take you directly there.)
http://www.scribd.com/doc/78410559/116/Fractional-Lots
It seems to be most commonly used to describe a piece of land that has a river running through it and so cannot be sold in complete lots.

When I looked up "fractional lot" I got 「端株」which is not the same thing. I thought of making my own term (「端敷地」?) but I wanted to ask the experts first. What do you think?