The Collaborative International Dictionary of English v.0.48:

Haemoglobin \H[ae]m`o*glo"bin\, n.
   Same as Hemoglobin.
   [1913 Webster]

WordNet (r) 3.0 (2006):

haemoglobin
    n 1: a hemoprotein composed of globin and heme that gives red
         blood cells their characteristic color; function primarily
         to transport oxygen from the lungs to the body tissues;
         "fish have simpler hemoglobin than mammals" [syn:
         hemoglobin, haemoglobin, Hb]