Heroes of science

by P. Martin Duncan

Nothing, however, seems to have given Linnæus so much satisfaction in reviewing the events of this period of his early history, as the intimate friendship he now contracted with a fellow-student, named Artedi, who afterwards distinguished himself by his knowledge of fishes and umbelliferous plants. To the picture he has drawn of his friend, Linnæus has added a slight sketch of himself. There was a great difference in the personal appearance, as well as in the temperament and disposition of the two youths. Artedi was of a tall and handsome figure, more serious, and of a deliberate judgment; whereas his friend was short in stature and stout, hasty in temper, and of a sanguine turn. The two companions pursued their favourite studies with an honourable spirit of emulation. They divided the kingdoms and provinces of nature between them, and while Linnæus yielded the palm to Artedi in ichthyology (the science of fish), the latter acknowledged Linnæus to be his superior in entomology, or that of insects. Each kept his discoveries to himself, though for no great length of time, since not a day passed without one surprising the other by narrating some new fact, so that emulation produced mutual industry of research, and stimulated each to new exertions.

Linnæus was now in his twenty-second year, about which time he met with a review of Le Vaillant’s treatise, “Sur la Structure des Fleurs” (“On the Structure of Flowers”), by which his curiosity was excited to a close examination of the stamens and pistils (the central and reproductive structures), and, perceiving the essential importance of these parts of the plant, he formed the design of a new method of arrangement, founded upon these organs. This was the first dawning idea of that great system upon which his subsequent fame was based.

A flower of a complete kind consists of the parts of the plant which reproduce or form the seed, enclosed within two particular envelopes. The envelopes of the flower are the beautifully coloured parts called petals, which form the corolla, or inner envelope, and the duller-coloured or green sepals outside the corolla, and which form the calyx.

Protected by these coverings, are the central parts or organs. Quite in the middle of the flower is the ovary, made up of one or several portions—the pistils, which contain the future seeds or ovules. The top of the whole, which projects in the middle of the flower, is the stigma, and the prolonged part beneath it is the style, and this surmounts the seed-case or ovary. Outside this central part, and between it and the corolla, are the stamens, each of which—for their number varies—may consist of a stalk or filament, bearing an anther, which is coloured, and contains the pollen, or dust, which fertilizes the ovule, by falling on to the stigma.

These central parts are the reproductive organs, and are those which, above all others, are the most important, for without them a plant cannot increase and multiply, and would become extinct. The floral envelopes, beautiful as they are, are not so essential, and are of secondary importance in classification. Now, in some kinds of plants the stigma and the ovary exist in one individual and the stamens in another. The plant which bears the ovary is called the female, and that which has the pollen-making part is termed the male. Hence it is said that plants have sexes. But in a vast number of plants these organs are combined in the same individual. Linnæus considered the stamen to be of primary importance, and established eleven classes of plants distinguished by the numbers of the stamens, and these all relate to plants in which the male and female organs are combined in the same individual. Thus the red valerian has one stamen only, and it was classed in monandria, the first part of the word meaning “one” and the last “male.” The lilac has two stamens, and was classed in the diandria—“two male;” and other plants were classified up to those which have ten stamens, the pink, for instance, as decandria. An eleventh class included all plants which bear flowers containing from twelve to nineteen stamens, such as mignonette. Then two more classes were invented to comprise—1, plants with twenty or more stamens placed on the calyx, as the cherry; 2, others with twenty or more stamens which are placed on stalks rising from below the ovary, as in the buttercup. Other classes were formed according to the relative length of the stamens, as in the foxglove and wallflower, and also from the grouping of the stamens in bundles. Then there were three very important classes in which the sexes are in separate flowers. Finally, the flowerless plants, such as the ferns, lichens, and fungi, were united as cryptogamia, having their organs of reproduction more or less concealed.

The next part of the classification refers to orders which are subdivisions of classes. The orders of the first thirteen classes, mentioned above, are founded on the number of styles (or of stigmas if these are absent), and the names given, relate to the number and the term gynia, or female.

Thus the order monogynia includes plants of all the thirteen classes that have only one style to each flower, such as the primrose; and so on, until polygynia, or “many female”—plants of such an order, having more than twelve styles, like the rose and clematis.

One class has a very important division into two orders, one of which has naked and the other covered seeds; another has orders from the shape of the fruit or pod. Linnæus divided the cryptogamia into six orders—the ferns, mosses, liverworts, lichens, fungi, and seaweeds. There is no doubt that this classification enables the name of a plant to be discovered, if it has been properly described and named, very easily, and it added to the facilities of classificatory botany. But it did not bring plants having many other and very important characters together, and it separated many which are closely allied by similar structures. It was and is called the artificial system. It was not a natural classification like that foreshadowed by Ray. The careful distinction of the sexes of plants was, of course, the foundation of the system, and to that Linnæus paid great attention. Writing a little treatise on the subject, he showed it to Celsius, who communicated it to Dr. Rudbeck. This man, free from the usual jealousy of the age, took Linnæus as his assistant, and asked him to lecture in the botanical garden. Thus the young man became a teacher in the very place where he had applied the year before for the humble situation of gardener. Dr. Rudbeck, moreover, took him into his house as tutor to his children, and thus he had access to a fine collection of books and drawings on natural history subjects. His mornings were then occupied in giving instruction to the students, and his evenings in composing the new system and meditating a general reformation in botanical science. He had no time to waste at Upsala. It will have been noticed how kindly Linnæus was treated by a few true lovers of science, and it was greatly to the honour of the good simple people of science-loving Scandinavia.

People imagine that the progress and prosperity of scientific men depend upon themselves alone; but many a promising career has been arrested by petty jealousy and the expression of ill will on the part of those who are second-rate men of science. On the other hand, truly distinguished scientific men are mostly only too glad to assist earnest, hard-working, and meritorious students. Linnæus found that he was no exception to the rule that appears to determine that a prosperous poor man shall have enemies. He was opposed by a Dr. Rosen on his return from foreign travel, but Linnæus stood his ground. But when his father suggested a voyage into Lapland to collect plants, Linnæus gladly seized the opportunity, and after arrangements had been made, he went to stay awhile at home.

Early in 1732 Linnæus left his father’s house, to set out on his arduous undertaking. On his way to Upsala he paid a visit to his former friend and preceptor, Stobæus, at Lund, and studied his collection of minerals, the only branch of natural history with which (he tells us) he was unacquainted. He shortly after proceeded to Upsala, from which place he set out on his journey alone, May 12th, 1732, “being at that time within half a day of twenty-five years of age.”