THE BIRDS OP THE PRIBILOP ISLANDS. 431 



The darker eggs all have much palei areas at their smaller ends than showa in the plate. Those 

 in the lower line do not show, in comparison with the others, as dark as they really are. They are 

 arranged in the plate according to color, heginning with the palest in the upper left-hand corner 

 (fig. 1) and ending with the darkest (fig. 2). These color differences fail to show in the reproduction. 



EXPLANATION OF PLATE XL. 



Fig. 1. Tringa ptilooHemis; a bunch of white- tipped neossoptiles from the hack and a single nefossoptile 



from the same bunch. 



Fig. 2. ; one of the unicolored neossoptiles which surrounds the ddts. 



Fig. 3. ; a back mesoptile with worn neossoptiles attached. 



Fig. 4. ; the tip of a mesoptile ramus with neossoptile attached and showing the swelling or 



hatching point between. 

 Fig. 5. Calcarius lappoiiicus alascensia; a neossoptile bunch attached to the tips of the rami of the 



growing mesoptile, confined by a part of the sheath remains; also, another mesoptile with 



somewhat separated neossoptiles and a single one showing the slight swelling. 

 Fig. 6. PhalaeroBorax urile; a filoplnme from breast of adult. 



Fig. 7. ; a filoplume from neck of immature (June). 



Fig. 8. ; a filoplume from neck of immature, showing a ramus along the raohis; sometimes two 



or more are found. 



Fig. 9. ; three filoplumes from neck of young about two months old. 



Fig. 10. ; the basal part of a fully grown neossoptile, showing the uneven division of the upper 



part of the calamus into double, triple, etc., parts. 

 Fig. 11. ; a part of the calamus of a similar neossoptile bunch, more highly magnified, with one 



of the parts torn down to show the homogeneous nature of the calamus. 

 Fig. 12. ; a bunch of down from a nestling about a week old, showing the bases of the growing 



rami forming a temporary calamus, which separates as it grows. 



EXPLANATION OF PLATE XLI. 



Fig. 1. Cyclorrhynchus paittaculus; tip of feather from white eye stripe. 



PMgs. 2, 3, 4. ; filoplumes from the nape and face. 



Fig. 4a. ; large, worn filoplume from the nape, showing crossing of radii. 



Fig. 5. Simorhynchus pitsillus; tip of white feather from' eye stripe. 



Figs. 6-7. ; filoplumes from back and nape. 



Fig. 8. ; white feather from forehead. 



Fig. 9. Uria lomvia arra; a downy (neossoptile) bunch from the neck of a few-days-old young, still 



partly inclosed by the sheath remains. 



Fig. 10. ; an unseparated neossoptile bunch and tip of same. 



Fig. 11. ; a bunch partly separated. 



Fig. 12. ; a bunch attached to the rami of a nestling back feather (mesoptile), but held by the 



persistent remains of the sheath. 

 Fig. 13. ; a similar bunch with part of the rami of a breast feather, the mesoptile rami being 



longer than on the back. 



Fig. 14. ) a mesoptile ramus with the neossoptile attached and showing the swelling between at a. 



Fig. 15. ; bases of two neossoptiles and the tips of two mesoptile rami longitudinally adhering — 



a common effect. 



Figs. 16-17. ; tips of a back and a breast mesoptile with many of the neossoptiles attached. 



Fig. 18. ; shows the point of breakage of the neossoptile rachis, usually below the swelling, but 



sometimes above, rarely central ; also one double-tipped — rare. 

 Fig. 19. ; a belly mesoptile with neossoptiles, showing double and long connection. 



