Erythrocyte size in some wild Spanish birds

An analysis was made of the erythrocyte dimensions of 21 species of the following Passeriformes common to the Iberian Peninsula: Fringilidae, Silvidae, Turdidae, Prunellidae, Ploceidae, Certhiidae, Emberizidae, Paridae, Troglodytidae and Apodiformes: F. Apodidae. The erythrocyte dimensions in Passeriformes were very uniform. Only the Silvidae presented a significant correlation (r = 0.96) between body size and cell area. In Apodiformes, cell area and cell length and width were significantly greater (p less than 0.01) than red blood cell dimensions in Passeriformes.