Oct. 13, 1887] 



NA TURE 



567 



on hop until frost overtakes the species in all conditions and 

 sweeps from the hop yards all individuals alike, perpetuating in 

 the egg state those only which reached the sexual condition on 

 the plum. 



(9) Each parthenogenciic female is capable of producing on 

 an average 100 young (the steai-motlicr probably being more 

 prolific) at the rate of one to six, or an average of three per 

 day, under favourable conditions. Each generation begins to 

 breed about the eighth day after birth, s 1 that the issue from a 

 single individual easily runs up, in the course of the summer, to 

 trillions. The number of leaves (700 hills, each with two poles 

 and two vines) to an acre of hops, as grown in the United States, 

 will not, on the average, exceed a million before the period of 

 blooming or burring ; so that the issue from a single stem- 

 mother may under favouring circumstances blight hundreds of 

 acres in the course of two or three months. 



(10) While meteorological conditions may materially affect the 

 increase and power for injury of the species, these are far more 

 truly predetermined and influenced by its natural enemies, many 

 of which have been studied and will be described. 



(11) The slight coloralional differtnces, as also the stnicfural 

 differences, including the variation in the cornicles on head and 

 basal joints of antennse, whether upon plum or hop, are pecu- 

 liarities of brood, and have no specific importance whatever. 



(12) The exact knowledge thus gained simplifies the protection 

 of the hop plant from Phorodon attack. Preventive measures 

 should consist in destroying the insect on plum in early spring 

 where the cultivation of this fruit is desired, and the extermina- 

 tion of the wild trees in the woods wherever the hop interest is 

 paramount ; also in avoiding the introduction of the pest into 

 new hop countries in the egg state upon plum cuttings or scions. 

 Direct treatment is simplified by the fact that the careful grower 

 is independent of slovenly neighbours, infection from one hop 

 yard to another not taking place. 



Experiments still under way have shown that there are many 

 effective remedies, and that the ordinary kerosene emulsion 

 diluted with twenty-five parts of water and sprayed with the 

 cyclone nozzle, or a soap made by boiling one pound of pure potash 

 in three pints of fish oil and three gallons of water, and this dis- 

 solved in eight gallons of water, and sprayed in the same way, 

 are thoroughly effectual remedies, and leave the plant uninjured. 

 The former costs 75 cents, the latter 30 cents, per acre, plus 

 the time of two men for three hours, plus appliances. The 

 object of further experimentation now being carried on is to 

 simplify and reduce the cost of these last to a minimum. As 

 they consist, however, essentially of a portable tank and a force- 

 pump with hose and spraying attachment, which, together, need 

 not involve a greater first outlay than 5 dollars to 10 dollars, and 

 as every American hop grower can afford to expend the larger 

 sum for the protection of a single acre, there is no longer any 

 excuse for allowing this pest to get the better of us. 



It is not my purpose, however, to enter into aphidicide details 

 in this communication, which I will conclude by brief reference 

 to the bearings of these discoveries in America on the problem 

 in Great Britain. The most comprehensive and satisfactory 

 review of the knowledge possessed on the subject in England 

 that has come to my notice, is that by my esteemed friend and 

 correspondent. Miss Eleanor A. Ormerod, Consulting Entomo- 

 logist of your Royal Agricultural Society, in her " Report of 

 Observations of Injurious Insects," &c., made in 1885. So far 

 as her own careful observations are concerned, they fully acconk 

 with the facts here set forth ; but on the authority of others, and 

 especially on the evidence of Mr. C. Whitehead, who reported 

 finding young lice and large viviparous females on hop shoots as 

 early as March 29, and that of Mr. A. Ward, who experimented 

 with surface dressings near Hereford, Miss Ormerod concludes 

 that attack on the hop begins in spring from wingless females 

 which come up from the hop hills, and, as a corollary, that 

 dressings to prevent such ascent are strongly to be recommended. 

 It is quite within the range of possibility, and what is known of 

 aphid life, that where the winters are mild, with scarcely any 

 frost, this Phorodon may continue on the hop from one year to 

 another in the parthenogenetic condition. If such is ever the 

 case in England, you have a somewhat different set of facts to 

 deal with here from what we have in America. But for the 

 reasons already stated in abstract, from many other detailed ob- 

 servations which it would be tedious to record here, as well as 

 from the ease with which erroneous conclusions are arrived at in 

 entomological matters of this kind, where not checked and proved 

 by the mo;t competent and careful study, I shall be inclined to \ 



believe that the facts in England are essentially tlie same as I 

 have found them in America, until convincing and trustworthy 

 evidence to the contrary be forthcoming. Mr. Whitehead may 

 have had another species under observation, and Mr. Ward s 

 surface dressings may have acted by repelling the winged female 

 migrating from Prunus, in the same way that buckwheat sown 

 among the hops is believed to do with us. 



EDUCATION IN GERMANY. 



TTHE following letter appeared in the Times on the loth 

 iust. : — 



Sir, — I should be glad if you could find space in your columns 

 for some remarks on the state of education i.i Germany, I have 

 just completed a short tour in this country, mainly to inquire 

 into its educational system, especially with reference to primary 

 and technical schools. England has at last roused herself to the 

 necessity for technical education. 



The Bill, which was unhappily crowded out last session, will 

 be reproduced next year, and, I trust, expanded to larger dimen- 

 sions. It will contain, I hope, a clause for the establishment of 

 evening continuation schools, for which object I gave notice of 

 an amendment last session. My trip to Germany has been 

 chiefly taken to learn what is doing here in this direction, and 

 what is the drift of educated German opinion. With your per- 

 mission I will briefly summarize my impressions. I premise by 

 observing that each State of the German Empire manages its 

 own education, and that the laws and regulations differ some- 

 what, so that general statements referring to all Germany can- 

 not be made without qualifications. I will not weary your 

 readers, however, l)y going into details respecting each State, 

 but place broadly before them the general features of German 

 education. 



The salient fact which strikes all observers is the universality 

 of good education in this c nintry. There is no such thing as an 

 uneducated class ; there are no such things, speaking broadly, as 

 neglected and uncared-for children. All classes of the com- 

 munity are better educated than the corresponding ones in our 

 country ; and this applies quite as much to primary as to 

 secondary education. Nothing struck me more than the general 

 intelligence of the humbler working classes. Waiters, porters, 

 guides, &c., have a knowledge of history, geography, and other 

 sU'ijects far beyond that possessed by corresponding classes i i 

 England, and the reason is not far to seek. The whole popula- 

 tion has long been passed through a thorough and comprehen- 

 sive system of instruction obligatory by law and far more 

 extended than is given in our elementary schools. I went 

 through several of these schools and observed the method of 

 teaching, which was simply admirable. The children are not 

 crammed, but are taught to reason from the earliest stages. 

 The first object of the teacher is to make his pupils comprehend 

 the meaning of everything they learn, and to carry them from 

 stage to stage so as to keep up an eager interest. 



1 saw no signs of weariness or apathy among either teachers or 

 scholars. The teaching was all vivd voc:. the teach^^ always 

 standing beside the blackboard and illus'.rating his subject by 

 object-lessons. The instruction was through the eye and hand 

 as well as the ear, and question and answer succeeded so sharply 

 as to keep the whole class on the qui vive. The teachers are, 

 as a body, much better trained than in England, and seem to b^ 

 enthusiasts in their calling, and the school holds a far higher 

 position in the social economy of the country than it does with 

 us. What I am saying here applies equally to Switzerland as 

 to Germany, and for educational purposes Zurich will compare 

 with any part of this empire. The main advantage, however, 

 that primary education has in Germany over England lies in the 

 regularity of attendance and the longer period of school life. 

 There is none of the difficulty of getting children to school that 

 exists in England ; the laws are very rigid and permit no 

 frivolous excuses, and, \\ hat is even more important, the people 

 entirely acquiesce in the laws, and are inclined rather to increase 

 than relax their rigour. It is well known that in London and 

 all our great cities a large part of the population seek to avoid 

 school attendance by every means in their power, and conse- 

 quently the attendance is most irregular. There is very little 

 of this in Germany ; at least I have not found it so. Then in 

 our country a great portion of our children are withdrawn 

 altogether from school, after passing the fourth or fifth standard, 

 at the age of eleven or twelve, whereas in Germany almost 



