21 is the only one listed as a boy's hat; it was available in blue or white.
19 is the only one listed as a girl's hat; it was available in pink or white.
All the rest were described as being for either a boy or a girl. 16 and 20 were offered in white only, 17 in a choice of white or light blue. The mitts (18) came in a set of two pair, one in white and one in blue).
My interpretation is that while pink was definitely a girl color at this point, blue was still considered a neutral option. I am also trying to figure out if the faces are made to look "masculine" or "feminine", but except for 19, it's seems too close to call.