ii6 



KNOWLEDGE & SCIENTIFIC NEWS. 



[June, 1904. 



no diminution oi i.ic < ulorophyll of either, and no degra- 

 dation of structure. 



.\ further stage in the acquiremeni of tlie parasitic 

 rather than the symbiotic habit is exhibited by the mistle- 

 toe and its allies. We are most of us familiar with the 

 mistletoe, an evergreen plant with pale greyish-green 

 lea\es, found growing on the poplar, apple, uVc. It arises 

 in all cases from the germination of seeds deposited by 

 buds in the bark of the branches of the host. The young 

 rootlet of the mistletoe inserts itself into the bark, and 

 penetrates the soft tissues of the cortex as far as the j-oung 

 wood. Subsequent growth and development, which are 

 accompanied by the co-incident grow-th and increased 

 thickness of the branch, lead to the establishment of a very 

 close union between the tissues of the two, and as the 

 plumule of the seed develops and the upper portion of the 

 mistletoe plant increases, the two are so firmly joined that 

 the organic food of the host is easily absorbed by the 

 intruder. The relationship is still symbiotic, for while 

 during the greater part of the year the host plant feeds 

 the mistletoe in preponderating measure, in the winter, 

 after the leaf-fall of the host, the evergreen guest contri- 

 butes to the nutrition of both. The plant shows, however, 

 the beginning of the inequality of symbiotic eflfort which 

 is the antecedent of parasitism. Co-incident with this w'e 

 find the beginning of the degradation of the chlorophyll 

 apparatus, the mistletoe possessing leaves of very grey- 

 green colour. 



The inequality thus established can be traced a stage 

 further in the genus Orohaiichc, the so-called broom -rapes, 

 which are far from uncommon among our wild plants. 

 They consist of a large fleshy stem ending in a spike of 

 flowers ; the stem bears a few almost rudimentary 

 leaves which are almost brown, having but little green 

 matter in them. The broom-rape is found seated upon 

 the roots of some other herbaceous plant, and is furnished 

 with a greatly thickened and swollen base by which the 

 attachment is made. The swelling is cfue to the absorp- 

 tion of nutritive matter from the host plant, which is now 

 almost the only source of food possessed by the intruder. 

 Parasitism is practically established; the chlorophyll 

 apparatus of the broom-rape is rudimentary and abortive, 

 and the burden of feeding both falls upon the host plant 

 which suffers in consequence. 



The common Dodder shows as yet another stage. The 

 plant infests many herbaceous plants, especially clover. 

 The seed germinates on the ground, and the young embryo 

 twines itself around some neighbouring stem. Having 

 established its hold, it forsakes the ground, and in all its 

 subsequent growth it twines more and more fully round 

 its host. The long twining stem bears no leaves, and 

 contains no chlorophyll. At intervals along its course it 

 puts out sucking root-like filaments, which perforate the 

 host and set up a close union between the tissues of the 

 two. So fed, the Dodder flowers and seeds, altogether at 

 the expense of its host. 



Our own flora shows us no more complete instance of 

 a parasite than this. In some tropical areas a parasite 

 can be met with which lives entirely wrapped up inside 

 the tissues of its host. The degradation of its structure 

 is complete, for its anatomical complexity is reduced to a 

 very close resemblance to the hyphal network of a fungus. 

 I lere and there an outgrowth of the plant penetrates the 

 surface of the host plant, and develops into a flower, 

 which in some cases has an enormous fleshy body. The 

 parasitic habit now dominates the plant ; it lives only to 

 produce its flower, it has lost all trace of normal struc- 

 ture, it obtains everything from the internal tissues of its 

 host, and stands before us indolent, atrophied, and yet 

 triumphant. 



The AvitobiograpKy of 

 Herbert Spencer. 



The late Mr. Herbert Spencer has written his " Auto- 

 biographj- " (Williams and Norgate) in a vein of exceeding 

 seriousness. Other men who have written their autobiogra- 

 phies endear themselves to their readers by their unconscious 

 revelation of character, even their human weaknesses. Mr. 

 Herbert Spencer had no human weaknesses ; he appears in his 

 autobiography as the personification of abstract thought. It 

 is true that he was a dutiful son; indeed, in speaking of his 

 mother, he approaches more nearly to tenderness than on any 

 other occasion, but even here he displays that detached clear- 

 sightedness that characterises all his relations in life. •• Of 

 my mother's intellect there is nothing special to be remarked," 

 he comments, and adds with that one touch of feeling already 

 mentioned. " speaking broadly, the world may be divided into 

 those who deserve little and get much, and those who desene 

 much and get little. My mother belonged to the latter class : 

 and it is a source of unceasing regret with me that I did not 

 do more to prevent her inclusion in this class." The reader is 

 feign to share her son"s retrospective sympathy for Mrs. 

 Spencer when he learns something of her husband's irritating 

 characteristics. " He held, for instance, that everyone should 

 speak clearly, and that those who did not ought to suffer the re- 

 sulting evil. Hence, if he did not understand some question 

 mv mother put, he would remain silent ; not asking what the 

 ([uestion was, and letting it go unanswered. He continued 

 this habit all through life, notwithstanding its futility. " Mr. 

 Spencer arraigns his earlier Huguenot and Wesleyan pro- 

 genitor? in the same scientific spirit, tracing in his own 

 character kindred traits derived from them. " That the spirit 

 of Nonconformity is shown by me in various directions, no one 

 can deny, " he says in conclusion. ■' The disregard of authority, 

 political, religious, or social, is very conspicuous. Along with 

 this there goes, in a transfigured form, a placing of principles 

 having superhuman origins above rules having human origins, 

 for throughout all writings of mine relating to the affairs of men. 

 it is contended that ethical injunctions stand above legal in- 

 junctions." 



The elder Mr. Spencer postponed his son's education on 

 grounds of health ; but, desulton,- as it was, at thirteen he bad 

 acquired considerably more general knowledge than is com- 

 mon at that age. Of Latin and Greek, he knew '• nothing 

 worth mentioning." Of English grammar or history, he was 

 entirely ignorant, and the deficiency in bis literary education 

 makes itself felt in the roughness of his English; but, on the 

 other hand, " my conceptions of physical principles and pro- 

 perties had considerable clearness, and I had a fair acquaint- 

 ance with sundry special phenomena in physics and chemistry," 

 .\ far more important mental acquisition, and one in which 

 school education is conspicuously deficient, was what Mr, 

 Spencer describes as the habit "of intellectual self-help," 

 which his father was continually inculcating. Shortly after he 

 was thirteen Herbert Spencer went to continue his education 

 at the house of an uncle, where be seems to have derived more 

 benefit from mental and moral discipline than the actual ac- 

 quisition of knowledge. Soon after his return home he entered 

 on a brief career as a teacher, his father's profession. In 1S57 

 he obtained a post under Mr. Charles Fox, Permanent Re- 

 sident Engineer of the London division of the London and 

 P)irmingham Railway during its process of construction. 



" I arrived in" London on the Sth November, 1S37. . . . 

 The Queen, who had but lately succeeded to the throne, and was 

 not yet crowned, dined with the Lord Mayor in the City on the 

 qth of November, and the occasion called for a State Pageant. 

 It was the only Royal procession or display of allied kind 

 which I ever saw. " He adds later: '• I was quite alive to the 

 responsibihties of my post and resolute to succeed. During 



