My whole is a reptile.

[14]

I am composed of 13 letters.

My 1, 13, 2, is the name of a female animal.

My 2, 5, 6, is a measure of length.

My 3, 4, 13, 6, is a musical instrument

My 8, 13, 7, 6, is a starting-place.

My 9, 12, 13, 5, is an image.

My 11 is a vowel.

My whole is the name of a group of islands in the Pacific Ocean.