This is the first pictorial chapter along the axis of tier 3; the “P1” of its name identifies this as a chapter devoted to pictorials. The
label for the photomicrograph, SxtrC11P1-1, identifies this as the first pictorial chapter of level 3 and, in addition, identifies the respective pictorial as the first pictorial (for this dummy section, there is
only one pictorial associated with this chapter. In the alternate system, this would be chapter SxtrC7 and the respective pictorial would be SxtrC7P1-1.