NATURE NOTES.

New Zealand Herald, Volume LXVIII, Issue 20982, 19 September 1931, Page 1 (Supplement)

NATURE NOTES.

LONG PEDIGREES. BY J. DRTIMMOND, F.L.S., F.Z.S. An amazing chapter in the insects' history discloses the almost unthinkably distant ages, in which they lived. When mammals, which now have dominion over all other creatures, were small, mean, and timorous, trembling at the sight of enemies and rushing for cover, the air was filled with insects that belonged to the diptera and the hymenoptera, the highest insect orders in these advanced days. There were winged insects as early as the Carboniferous Period, which was in the Primary Era, when the world was very primitive. Many remains in the Carboniferous rocks of France and North America show that there lived in that remote age a race of insects with the general build and appearance of our own cockroaches. In the Carboniferous rocks of France there are the remains of gigantic insects so closely resembling modern dragon flies as to be accepted as their ancestors. This chapter has been written in other words in " Insects, Their Structure and Life," by Dr. G. H. Carpenter, keeper of the Manchester Museum, formerly Professor of Zoology in the Royal College of Science for Ireland. Although, as we all know, there were occasions when the mountains were removed and the hills departed, the " everlasting hills " remain emblems of age-long time, while the life of each individual insect spans only a few days, months or years. " Vet these creatures," Dr. Carpenter reminds us, " are the latest link in a long chain of life stretching back to a time before the hills in which they dwell were brought forth." Insects have changed in form and structure during their earthly pilgrimage, but landscapes have changed moro rapidly and to a much greater degree than the insect types that adorn them. Seeking the insects' origins, Dr. Carpenter goes back much further than the time when the oldest fossil-bearing rocks were laid down. He sees in imagination primitive creatures of the sea called arthropods—that is, jointed-feet. From these the crustaceans branched off, but continued to live in the water. A second group, also leaving the parent stock, formed themselves into the arachnids, including spiders, scorpions and their allies. They went to dwell mostly on the land. 'A third diverging group became the ancestors of all insects. Acquiring the faculty of flight, which man has acquired mechanically only now, insects became the leading class of land invertebrates. In their higher orders they, as creatures of the air, worked into their life histories startling transformations. Nothing is more delicately beautiful than the gauzy wings of a dragon-fly, nothing more colourfully beautiful than the scaly wings of a butterfly. The way in which insects' wings are developed varies greatly, but they are never developed completely until late in life. They arise as outgrowths from the wall of the body. It is suggested that they formerly served as sails, parachutes, or gliders, helping their owners to take flying leaps through the air, but their origin at present is regarded by Dr. Carpenter as a mystery. The only thing is to marvel at their efficiency and excellent beauty. Dr. Carpenter writes of many phases of the insects' life and structure. This is the second edition of his book, revised and brought, up-to-date. As a guide to another world, more densely populated, more varied, and more ancient than our own, the student and the general reader alike can place confidence in it. A copy of the well-illustrated second edition has been sent by the publishers, Messrs. J. 31. Dent and Company, London. , Dr. A. R. Wallace puts forward a theory that the white tails of animals, of antelopes and rabbits, for instance, are recognition marks, enabling members of a herd, of a company or of a flock to follow the leaders in escaping from enemies. ' This may be the case with the pukeko, which has conspicuous under white tail-coverts; but the pukeko's rare relative the Notornis,. or takahe, has the same noticeable character, yet it has no natural enemies from which it might flee. As far as is known, the Notornis dwells solitarily in the wild /country of the Southern Sounds. Only four isolated individuals have been found. It may or may not bo extinct. In either case, there is nothing to show in it a gregarious habit. Recognition marks would bo of no use to it. An argument may be stated that in past ages the ancestors of the Notornis were gregarious, and had natural enemies, that those remote ancestors developed white tails as recognition marks, and that the recognition marks have persisted, although of no practical use now; but this, it must be confessed, is somewhat far-fetched. Another point is that, if white tails are recognition marks, it is doubtful how far the advantage of friendly recognition through them compensates for the fact that they reveal the owners of the white tails to enemies. On the sifting of evidence, the theory does not seem very sound. Lofty and handsome, ornamented with round berries, jet black and shiny, embedded in bright scarlet cup-shaped fleshy envelopes, singular, conspicuous and pretty, the titoki is one of the bestknown members of the forests in the North Island, but, disdaining colder climates, grows 110 further south than North Westland and Banks Peninsula. The scarlet envelopes of the seed induced botanists to give this tree the Greek name of a rooster, • Alectryon, the envelope suggesting to them a rooster's red comb. The erect panicles of flowers, from four inches to twelve inches long, their pollen-bearing anthers dark red, may be seen from November to December. The Maoris used an oil in the berries for a perfume. Early settlers used the titoki's tough and elastic timber for their bullockyokes, when bullock drays, more plentiful than traps and buggies, were the fashion in transport. The timber is still used for axe handles and other purposes. Still, the titoki is at its best as an ornament of the forests. Some people call it the New Zealand ash. but its Maori name is preferable, Officially, it is Alectryon excelsum. Its only close connection, Alectryon grandis, has been reported from only a small clump on the Three Kings Islands, north of North Cape. In the Cretaceous Period, the golden age of reptiles, there lived in New Zealand waters, and in almost every sea, a strange creature which, on account of its shape, was called the ichthyosaurus, mean- y ing the fish-reptile. It was not one of the giants of those days, being not more than about twelve feet long, but it was very plentiful. Its voracity is shown by the presence in the fossilised stomach" of a single individual of the remains of more than 200 ancient squids. The species of squid 011 which this individual had feasted was amazingly plentiful, but, like the ichthyosaurus, it was blotted out many millions of years ago. At least some female ichthyosaurus produced their young alive, from eight to ten at a birth, "judging by the remains of young found inside a fossil parent. These marine reptiles had a spectacular rise to dominance ami a spectacular fall. It i s believed that they were of low intelligence, and that, at the end of the Cretaceous Period, they failed to change rapidly enough to meet fresh conditions. Smaller creatures, with more brains, attacking the ichthyosaurus, may have put the finishing stroke on their brilliant career.