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 July, 9o6 [ LAND BIRDS OF SAN ONOFRE, CALIFORNIA 93 Five pairs of birds were watched to see if they would lay eggs of the same number, size, shape and markings from year to year. Three pairs of birds occu- pied the same nests during the two years and the other two pairs each moved to other nests in the same grove. The individuals had certain characteristics, as dark or light plmnage or a peculiar harsh note while one pair made themselves conspicuous by their silence; so identification was quite certain and we were reasonably sure that we did not get the pairs confused. In i9o 5 one pair produced a set of two eggs which measure 2.53 x 1.78, 2.55 x 1.83 inches. One egg of this set was covered with clay colored markings which merged together forming a hazy cloud around the large end. The other egg was similar to this but the markings were of a vinaceous buff tint and surrounded the small end. This year a set of three eggs laid by the same bird measure 2.38 x 1.8i, 2.32 x .76, 2.42 x 1.78 inches'. These eggs were evenly covered with splashes that vary in size from a pin point to 25 square millimeters and fade from a cinna- mon rufous to heliotrope purple. Thus it will be seen that these two sets differ, in number, size, shape and markings. Another pair laid three eggs last year which measure 2.34x.87, 2.33x.88, 2.32x.87 inches. Two of these eggs were covered about the little end with chestnut colored spots that were arranged in a concentric position around the small end. These spots were large and gradually faded from chestnut to hazel as they approached the end of the egg. The other egg had only a few scattering hazel markings. This year this pair laid four eggs which have almost identically the same ground color, shape and markings as last year's eggs. The eggs meas- ured 2.28xt.86, 2.29x.83, 2.29x.84, 2.3oxi.84 In this instance the bird laid the same type of eggs for two consecutive years. The third pair laid a set of two eggs in 19o 5. The ground color of these eggs was almost white. One egg was covered about the small end with clear-cut chestnut splashes that centered about the small end of the egg. The other egg had a few very small vinaceous spots scattered evenly over its surface. This year this pair laid a set of three eggs. The ground color of this set was darker than that of the other set. One egg was covered about the small end with heavy burnt umber splashes. The second egg had a number of large brown spots on the large eud, while the third egg was covered over the large end with indistinct clay colored splashes. The two sets measure 2.35xi.82, 2.37x.83 and 2.33 x 1.84, 2.28 x.87 (the third egg was broken). The fourth pair laid two eggs this year as well as last year. The set last year had a dirty ground color and was marked with a few scattering hazel smudges. The eggs laid this year were nearly, exactly the same in size, ground color, incu- bation and markings. The last pair laid a set of two in i9o 5. These eggs were small (2.23x.73, 2.3ox.78 ) and had a few heavy spiral vinaceous.spots on the large end. Another set from the same pair of birds measure 2.33xi89, 2.24xi.82 inches. One of these eggs was particularly handsome as it was heavily marked on the little end with heavy clear-cut cinnamon-rufous splashes. The other egg was similar only the markings were not so brilliant. These observations show that some pairs of red-tails lay the same shape, size, number and marked eggs, for two consecutive years. But in the present instance the majority did not do this. In I9O 4 we saw several Pacific horned 0wls, but they seemed to have almost disappeared in I9O 5. I was also informed that horned owls were rarely met with that season in the central part of the County, where they had formerly been corn-