Question

In stumbled upon the following sentence in Chordate Embryology and Histology while reading a paragraph on the Fate map of amphibian blastula-

Beneath the notochordal mesoderm and towards the vegetal pole there lies a narrow strip of cells which forms the prechordal connective tissues of the embryo and hence the strip is called pre-chordal plate.

Here's a link to an image which I wish to attach with this question: http://biology.stackexchange.com/questions/53457/pre-chordal-plate

What are prechordal connective tissues that this prechordal plate forms later in development?