Scribe 2 of 𝓞 apparently missed the and at the beginning of verse 11. Oliver Cowdery emended the text by supralinearly inserting an ampersand. His emendation is probably correct since elsewhere in 1 Nephi, when there is a conversation with either the spirit or the angel of the Lord (here in chapter 4 or in chapters 11–14), we always get “and X saith/said” (30 times), where X refers to the spirit or the angel. In other words, there is always a connecting and with the previous discourse. In 1 Nephi, other connectors (such as for, but, and now) are never found preceding “X saith /said”, only and.
We also have abundant evidence from scribe 2’s corrections that he tended to drop his and ’s. In all of the following examples, he caught his error and corrected it in 𝓞. Note in particular the example in 1 Nephi 13:3 of “he saith unto me”, which parallels “and the Spirit saith unto me again” in 1 Nephi 4:11:
Summary: Accept Oliver Cowdery’s insertion in 𝓞 of an ampersand before “the Spirit saith unto me again”; elsewhere the text in 1 Nephi always has the conjunction and before “X saith/said”; sometimes scribe 2 of 𝓞 omitted the and when he initially wrote down the text, but generally he caught his error and corrected it.