IN TOUCH WITH NATURE

Otago Daily Times, Issue 19762, 13 April 1926, Page 2

IN TOUCH WITH NATURE

BT J DRUMMOND, P US.. F.Z.S.

THE GIANT PUFF-BALLS.

A monstrous puff-ball, more than a foot in diameter, found by children in a dry ditch near the Post Office at Whitianga, at the head of Mercury Bay, is a member of the giant puff-ball group, the Lyeoperdon. Photographs of the puffball, with a cup beside it to show its bulk, have been sent by Mr J. H. Hudson, of Whitianga, who states that in texture it resembles the larger sort of mush* room, and in weight it is comparable to a piece of pumice. The specimen is unusually large, but it is small compared with a member of, probably, the same species, Lyeoperdon Bovista, found in America. This was sft 4in at its greatest diameter and 4ft Gin at its least diameter, and 9Jin high.

In the puff-ball group of the fungi the body of the plant usually is globular, as in the Whitianga specimen. The spores, when ripe, are a powdery mass intermingled with a web of threads. The spore-bearing surface occupies most of the interior of the plant. The spores at maturity, if the atmospheric conditions are suitable, emerge in puffs that often resemble smoke. Puff-balls find it necessary to produce prodigious numbers of spores, in the same way as some species of fishes must produce prodigious numbers of 2eggs to ensure fertility. As myriads of puff-ball spores fail to produce plants, prodigality in the production of spores is essential. An actual estimate by an English fungaologist —mycologist now —places the number of spores produced by a single large giant puff-ball, perhaps about the same size as the Whitianga one, at 7,000,000,000,000. A single shaggy-cap fungus, it is estimated, produced 5,000,000,000 spores, and a dryad’s saddle produced 11,000,000,000.

Many species of fungi are _ cosmopolitan. This is accounted for, in part, at least, by the ease with which the invisible spores, so plentiful and so light, are carried by insects and birds, and, particularly, on the wings of che wind. Some fungi are as clever as some dowering plants in using insects for the purpose of dispersal. These fungi attract insects by producing sugary secretions, on whith the insects feed. One species embeds its spores in a green, sticky mucus with a strong carrion smell. Insects eat the mucus until they become almost comatose. They carry away many spores and disperse them. A very small puff-ball, using a catapult, hurls its spores about a yard into the air in order that they may be dispersed by the wind. A fungus parasite that attracts flies and kills them off in great numbers shoots out its spores like bullets from a rifle. The spores sometimes form a whitish halo around a fly that has died on a window pane.

Puff-balls, like some other fungi, have some amazing peculiarities. One of these is their rapid growth. A writer on puff-balls some 65 years ago stated that “the giant puff-ball increases from the size of a pea to that of a melon in a single night.” Messrs R. T. and F. W. Rolfe, authors of the best popular book on the fungi, state that puff-balls’ facility in this direction is exaggerated, but that they shoot up surprisingly quickly. A puff-ball has a true growth and an apparent growth, which consists of the rapid distension of tissue already formed, but previously unexpanded. A popular belief that mushrooms grow in a night has arisen from their apparent growth. Messrs Rolfe, who have a more intimate acquaintance with the strange inhabitants of the fungus world than most humans are privileged to enjoy, explain that in most cases fungi must generate their spores when climatic conditions are suitable. To prepare for this they have constructed organs that can be gorged with water and rapidly distended, and erected at the proper time. In addition to this, the true growth of fungi is much more rapid than in the case of other plants. For one thing, fungi have a large number of growing points, while more highly _ de-. veloped plants have limited and localised growing layers.

A primrose on the_ river’s brim may be merely a yellow primrose and nothing more to some people, and a lovely flower to othersi It will have still greater attractions to those who read a book by Professor Junius Henderson, Professor of Natural History at, the University of Colorado. The primrose is on the river’s brim, he explains, because events followed each other in a long series, in orderly succession, under Nature’s unchanging, interacting, ete.rnal laws. After Nature’s geological processes had prepared for the primrose by operating for ages on rock and soil and river, the primrose’s seed fell on the river’s brim, sprouted, and sent roots into the moist, nourishing ground. The primrose set up its leafy laboratory for sunlight to use in manufacturing chlorophyll, and it nodded in the breeze and spread its petals to ripen its fruit, as its ancestors had done for, perhaps, 1,000,000 generations before it, as its descendants may do for generations to come.

This American professor’s book discusses erosion, the rise and decline of continents, the crumpling of the earth’s surface, waterfalls, rivers, lakes, mountains, glaciers, volcanoes, earthquakes, the place of plants and animals in landscapes and “ the most stupendous fact on the face of the earth, the ocean.” The theme is that every landscape has a history—a past, a present, and a future —which may be read in Nature’s own book. These particular pages of that great book have been translated interestingly by Professor Henderson. Everything is described graphically, mostly in generalisations.

Erosion, .for instance, is Nature’s gigantic chisel and plane. Every hill has been partly or wholly fashioned by that tool, every valley is partly its handiwork every plain bears its impress. Nature’s transport system is running water. In comparison with it, all the railway systems in the world combined dwindle into insignificance. Dust that floats in every summer breeze may mar the scenery today, but it may make the landscape of the future. Mountains, rivers, lakes, shores, and other features all have life histories, periods of youth, of maturity, and of old age. It is delightful to be able to distinguish geological formations and to assign their ages, in the light even of the imperfect knowledge available There is greater delight in viewing geological and geographical features in relation to their environment and to the plants and animals that beautify them. Fiom this point of view a landscape has a vaster aspect. Professor Henderson shows in "Geology in its Relation to Landscape ” how this may be done. He might have dedicated his book to Nature and to things in the material world that are beautiful. It reflects the soul of a geologist. A copy has been sent by the publishers, the Stratford Company. Boston. Massachusetts.

The study of botany has changed remarkably during the past 15 years. Fresh interest has been given to it by a school styled ecologists. Taking as their title the Greek word for house, abode, or dwelling, they concentrate attention on plants as they live in their natural homes. Ecologists familiarise them selves with plants’ household affairs. Ecology must be studied primarily in the field, ns it considers a plant not only as an individual, but also as a member of a plant community, in relation to its environment and to its neighbours—how it' acts upon them and how they act upon it The method is like sociology as a study of mankind. The anatomist and the physiologist study the structure and the working of the human body. To study what man does in the world it is necessary to go out into the world and see how he lives and works amongst other men. T(& study plants—also the lower animals —in the same way, ecological methods must be followed.

• The British Ecological Society has been formed to foster this study, and its president (Mr A. G. Hansley), to help beginners, has published “ Practical Plant Ecology.” Students attracted to ecological work —they can rest assured that they will find it fascinating—can have no better guide than Mr Tansley’s book. In addition to setting out the principles and scope of ecology, it gives practical advice, even for making maps, keeping notes, and providing field equipment. Mr Tansley is convinced that ecology baa a high odu*

cational value. His hook will give teachers a clear idea of the subject’s possibilities. His ideal school garden, by the way, is not a tidy one, devoted solely to well-kept flowers and to vegetables, but an outdoor laboratory for the study of the conditions under which plants succeed or fail. It gives them a distinct human interest. His useful book has been published by Messrs George Allen and Unwin, London.