36 



being merely a resting place for birds in their peri- 

 odical migrations across the Mediterranean. The 

 arrivals of birds chiefly take place at the period of the 

 vernal and autumnal equinoxes." The ornithologist 

 must be on the alert from the middle of March till the 

 end of April, and also during the autumn migration 

 which is known as " the great passage." " Occasional 

 visitors appear during the winter months, and a 

 $ew in summer. Birds generally arrive and leave 

 at night, and do not usually remain more than one 

 day, thus giving little opportunity of studying their 

 habits. Some species however remain a few months 

 on the island, and several of them breed here 

 en-route for Europe, whilst flocks chiefly of Grallatores 

 and Natatores may be seen passing high in the ai r 

 without alighting." 



<e The influence exerted by the wind over these 

 migrations is no doubt very great. In spring, the 

 quails and most of the short-winged and smaller 

 birds, and such as are of weak flight, though not unfre- 

 quently arriving in calm weather, generally appear 

 during the prevalence of winds from the N. N. 

 W. to S. S. W., and in autumn with those from 

 the S. S. E. to N. N. E., being probably stopped 

 in their migratory course, and driven to seek rest 

 on our shores." Dr. Adams is of opinion that a 

 strong sirocco or north wind and dense sea-haze 

 cause the quail to come upon the island unawares. 

 <( Sometimes a fresh breeze springing up from any 



