MARVELLOUS JOURNEY

Evening Star, Issue 19002, 25 July 1925, Page 19

MARVELLOUS JOURNEY

BUTTERFLIES’ GREAT TREK TROPICS TO THE ARCTIC. Ships passing along the English Channel in the spring often see swarms of butterflies crossing the sea from Franco to Eng* land. These butterflies are known as “ painted ladies,” and they go to England every year from the south, though in varying numbers. Sometimes hundreds of thousands of them cross the Channel, and in other years only a few, but were it not for these visitors from abroad England would have no painted lady butterflies at all, for although on arrival they lay eggs and caterpillars hatch out, and they m turn change into butterflies, these all die off when winter comes, and the country is loft with none to carry on the race. Some wonderful information about these " painted ladies,” recently came to light as a result of the investigations of scientists. Mr C. B. Williams, the Chief Entomologist to the Egyptian Ministry of Agriculture, tells the story. Their place of origin, it seems, is south of the geat desert belt that crosses Africa and Western Asia. FROM AFRICA TO ICELAND. “ Painted ladies ” have been seen in large numbers entering Algeria from the south, crossing the Nile Valley near Cairo, and entering Palestine from the East for days on end. They have been seen massed in great numbers, apparently resting during migration, in the Egyptian desert near the Sudan border. Farther south they have not been recorded, and it is therefore assumed that their breeding places must be just south of the long border line stretching across North Africa and Asia Minor. In the early spring the butterflies from Africa begin to move north, and they arrive at the southern shores of the Mediterranean about April. From Palestine masses of “painted ladies” fly through Syria and Turkey and the Balkan States, and those which have arrived in Egypt and Tripoli and Algeria fly across the Mediterranean to Southern Europe, which they reach in early May. Thence the' butterflies pass on, probably leaving stragglers behind all the time, until at last they cross the English Channel and land on the southern shores of England at the end of May. But this great trek is not over yet. They continue their journey, flying to the north of Scotland, where they arrive about midJune, and some still go on until they reach Iceland, their northern limit, in July. IN THE TEETH OF THE WIND. It is an amazing journey for such frail creatures, liable, one would think, to be driven about by every wind and storm. Yet they do not fly with the wind, but in its teeth. From their breeding gerunds ‘in Africa to Iceland is about 4,000 miles, and this great trek of the “ painted ladies ” across half a hemisphere is one of the greatest marvels of migration known to science. In some years countless millions of them arrive in Western Europe from the south. , How do they know their way? There is no evidence that any of the butterflies ever go back again. _ They have never been seen travelling in a reverse direction, yet it is so amazing that fresh broods should year after year be born in Africa and always find their way to the same countries in the north that some scientists think that numbers of them must return. It is suggested that, they either go back in swarms at night or fly back alone as individuals, thus escaping notice. But of this there is no evidence, and it seems unlikely that if they return, they shouldnot at some time or other have been seen doing so. LAYING OF THE EGGS. This migration of the butterflies is something 'quite different from that of the birds, for whereas the birds lay their eggs either in the place they come from or the place they go to, the “ painted ladies ” lay theirs- throughout the whole range of their migration. In fact, so marvellous is the long flight from the deserts of the north that Mr Williams suggests that the butterflies which begin the flight are not the same as* those that reach the more northerly areas, but that on the way they lay eggs which hatch out as caterpillars, and become butterflies, and that these in turn move north. According to this theory, the migration is, in fact, a kind of relay race, different sets of butterflies taking up the journey where their predecessors left off. It is an interesting theory, but makes the migration still more of a mystery. Such a wonderful discovery will no doubt be followed up, and there will bo further investigations, which may lead to more amazing disclosures about this beautiful butterfly.