F. B. KIRKM AN : VARIATION IN NESTS OF TERNS. 7^ 



The Arctic Terns' nests were found, during the summer 

 of 1905, in the protected area at the south end of Walney 

 Island, off Barrow-in-Furness. I made careful notes of 

 thirty, of which thirteen lay on the patches of bare sand 

 in between the sandhills, eleven in the shingle patches 

 that alternated with the sand, four on the beach, and two 

 among the bent, a rough stringy grass growing abundantly 

 at Walney, and serving to cord up the wind-made shifting 

 sandhills, thus rendering them more or less permanent. 



Fig. 2. — Pebble-paved Nest of Arctic Tern on Beach. 



There were four distinct types of nest with intermediate 

 forms. The majority, eighteen in number, representing 

 the first t3rpe, were made of varying amounts of bent. 

 Nearly all these nests proclaimed the individuality of 

 their architects. Some consisted of an outer circle of 

 bent, the inside being left bare. One, evidently the 

 work of a bird with a geometrical turn of mind, showed 

 a semi-circle of bent, and a semi-circle of sand, while 

 another was adorned with an oyster-shell and a feather, 

 if not put there, in any case left unremoved. To some 



