(Dwarf) cabbage butterflies

[Kenelm Philip]

	Daniel Glaeske noted dwarf cabbage butterflies and asked if this
were a known phenotype.

	This phenomenon turns up in many species of butterfly--I have run
into such individuals a number of times in Alaska. The usual explanation
is that these pupated after the 4th instar rather than the 5th--but I have
not seen a proof of that seemingly plausible theory. Nor have I seen a
discussion of why this happens, and what external conditions (temperature
or humidity?) might be involved.

							Ken Philip
fnkwp at aurora.alaska.edu