daf bit: Pesachim 62

Today's daf is 63 and is mostly a discussion of factors that affect the fitness of the Pesach offering. On the way there I noticed an interesting tidbit at the end of the previous page.

In the g'mara Rami ben R. Yehudah says: since the day that the Book of Genealogies was hidden, the strength of the Sages has been impaired and the light of their eyes has been dimmed. Rashi says this is because the book contained the reasons for many of the laws and those have been lost. Mar Zutra said: between "Azel" and "Azel" (referring to a passage in Chronicles) they were laden with four hundred camels of exegetical interpretations! (62b)

A comment in the Soncino edition notes that this last passage is not meant to be taken literally.

I'm looking for more information about the Book of Genealogies. There's a lead there in Hebrew (which I can't read well enough); help most definitely welcome!