Study Guide Nazir 53

Rami bar Hama asked: Is one stricter with the spinal cord or skull that if one has a quarter kav of bones from them, does the nazir need to shave on account of them, as opposed to other bones where a half kav is needed? The first answer, given by Rava from our Mishna is rejected. A second answer is brought from an opinion of Shamai brought on Nazir 52b, but is rejected as well. Rabbi Eliezer explains that at an earlier stage, there was a debate about whether only half a kav/log or a even quarter kav/log would make one impure, but no distinction was made between nazir and other issues. At a later stage, the courts distinguished between a nazir needing to shave/one not being able to do the Pesach sacrifice (a half kav/log) and the ability to eat truma and kodashim (a quarter kav/log).   Why is the language "on these" used in the Mishna twice - what can be learned from those words? Even though a nazir doesn't shave for a quarter kav of bones in a tent, he would shave if he touched or carried them. This is derived from the language in the next Mishna or perhaps the language at the end of our Mishna). But if so, wouldn't that already be derived from the law of a bone the size of a barley? They explain that it means if they are ground into a powder-lie substance, they will be impure if they are a quarter kav. The Mishna mentions a limb from a dead body or a live body that has enough flesh on it. What if it does not? Since it is not mentioned in the upcoming Mishna, Rabbi Yochanan and Reish Lakish disagree about whether a nazir would have to shave or not. How does each prove his approach? Two questions are raised Rabbi Yochanan's argument from the next Mishna, but are resolved. What size limb is being argued about here? If it is larger than the size of a barley, how can Rabbi Yochanan say that the nazir doesn't shave? If it is smaller, how can Reish Lakish say that the nazir shaves?