April 5, 1900] 



NATURE 



553 



blue light the colour of the animal becomes more or less rapidly 

 of the nocturnal tint, and the tissues acquire the characteristic 

 transparency. Further, that if these screens be employed all 

 night the prawns do not recover so soon the next morning as do 

 those which are simultaneously exposed to the same source of 

 light in open white dishes. Without attempting to fully explain 

 this effect of monochromatic light, Keeble and Gamble conclude 

 that the prawns do not respond to light of any colour in virtue of 

 its specific wave-length, and that in so far a colour-sense 

 cannot be demonstrated. 



Other experiments, however, show that under natural con- 

 ditions Hippolyte varians has the power of choosing from a 

 mixed quantity of weed that one on which it naturally occurs, 

 and with which it agrees in colour. This power of choice is, 

 however, very erratically exhibited. Nevertheless, it would 

 appear to be the chief means of safety should the prawn be 

 violently washed away from its usual habitat. 



The colour-changes in Hippolyte are largely, if not entirely, 

 controlled by the nervous system. That the eyes are not 

 essential to the daily rhythmic colour-cycle is shown by the 

 fact that blinded prawns nocturne and recover as completely as 

 normal ones, but more slowly and somewhat more erratically. 

 The periodicity does not reside in the eyes and optic ganglia. 

 It is a function of the rest of the nervous system. That the eye 

 is a most important auxiliary in modifying the control of the 

 central system cannot be doubted ; but it cannot be supposed 

 that the light, acting through the eye, differentiates such stimuli 

 as to cause each colour-variety to show, as in a mirror, the 

 pattern of its weed. There must be local control, and tl^is, under 

 the strong central organisation, seems to be the efficient force. 



The paper closes by a note on the response of the chromato- 

 phores of the sf^a-larva of Hippolyte. These colour-elements 

 develop before the time of hatching, and occur, chiefly in pairs, 

 symmetrically throughout the body. Changes of light-intensity, 

 such as alternately placing the larvae on a black and then a 

 white ground, are rapidly followed by changes in the pigrnents. 

 In the former case, the yellow-green pigment expands ; in the 

 latter, it contracts and the red pigment spreads out. So far 

 as the observations went, these larvae did not exhibit a blue 

 nocturnal colour phase, and further investigation, upon which 

 the authors are engaged, will have to decide at what period in 

 the life-history periodicity sets in ; whether there is a particular 

 phase in development during which the young prawn is specially 

 sensitive to the colour of its surroundings ; and if at that time 

 its diurnal colour becomes relatively fixed, as the animal grows 

 into these surroundings. 



NATURE STUDY IN RURAL SCHOOLS. 

 "pVERYONE who is familiar with the work of our Education 

 Department knows that the Inspectors are given explicit 

 instructions to discountenance the unintelligent teaching of 

 science, and to do everything in their power to encourage the 

 observation and study of natural objects and phenomena. The 

 " object lessons," which are given in the lower standards, are 

 intended to lead the pupils to use their eyes and compare one 

 thing with another ; and though they have become in some 

 schools of too detailed a character to develop the faculties of 

 observation and reasoning, the fault is chiefly due to the fact 

 that many teachers are not observers of nature themselves, and 

 are therefore unable to describe natural things except in the 

 language of the text-book. Every effort has, however, been 

 made by the Education Department to show teachers that this 

 is not the kind of teaching intended to be given as object lessons. 

 Several circulars have been issued containing instructions as to 

 what should be done, and the new Board of Education has 

 shown sympathy with the work of arousing interest in nature 

 by issuing a circular, from which the following extracts have 

 been taken, to managers and teachers of rural elementary 

 schools. The issue of this document by Sir G. W. Kekewich at 

 the very commencement of the work of the Board of which he is 

 the secretary, may, we trust, be taken as an indication that 

 increased attention is to be given to the teaching of scientific 

 subjects in elementary schools : — 



The Board would deprecate the idea of giving in rural 

 elementary schools any professional training in practical agri- 

 culture, but they think that teachers should lose no opportunity 

 of giving their scholars an intelligent knowledge of the sur- 



NO. 1588, VOL. 61] 



roundings of ordinary rural life and of showing them how to 

 observe the processes of nature fbr themselves. One of the 

 main objects of the teacher should be to develop in every boy 

 and girl that habit of inquiry and research so natural to children ; 

 they should be encouraged to ask their own questions about the 

 simple phenomena of nature which they see around them, and 

 themselves to search for flowers, plants, insects, and other 

 objects to illustrate the lessons which they have learnt with 

 their teacher. 



The Board consider it, moreover, highly desirable that the 

 natural activities of children should be turned to useful account 

 — that their eyes, for example, should be trained to recognise 

 plants and insects that are useful or injurious (as the case may 

 be) to the agriculturist, that their hands should be trained to 

 some of the practical dexterities of rural life, and not merely to 

 the use of pen and pencil, and that they should be taught, when 

 circumstances permit, how to handle the simpler tools that 

 are used in the garden or on the farm, before their school life 

 over. 



The Board are of opinion that one valuable means of evoking 

 interest in country life is to select for the object-lessons of the 

 lower standards subjects that have a connection with the daily 

 surroundings of the children, and that these lessons should lay 

 the foundation of a somewhat more comprehensive teaching of 

 a similar kind in the upper standards. But these object-lessons- 

 must not be, as is too often the case, mere repetitions of descrip- 

 tions from text- books, nor a mechanical interchange of set 

 questions and answers between teacher and class. To be of 

 any real use in stimulating the intelligence, the object-lessons 

 should be the practising ground for observation and inference, 

 and they should be constantly illustrated by simple experiments 

 and practical work in which the children can take part, and 

 which they can repeat for themselves at home with their own 

 hands. Specimens of such courses can be obtained on appli- 

 cation to the Board of Education. These may be varied in- 

 definitely to suit the needs of particular districts. They are 

 meant to be typical and suggestive, and teachers, it is hoped, 

 will frame others at their discretion. Further, these lessons- 

 are enhanced in value if they are connected with other subjects 

 of study. The object-lesson, for example, and the drawing, 

 lesson may often be associated together, and the children should 

 be taught to draw actual objects of graduated difficulty, and 

 not merely to work from copies. In this way, they will gain a 

 much more real knowledge of common implements, fruits, 

 leaves, and insects than if these had been merely described by 

 the teacher or read about in a lesson-book. Composition exer- 

 cises may also be given — after the practical experiments and 

 observations have been made — (or the purpose of training the 

 children to express in words both what they have seen and the 

 inferences which they draw from what they have seen ; and the 

 children should be frequently required and helped to describe 

 in their exercise books sights of familiar occurrence in the woods 

 and in the fields. Problems in arithmetic connected with rural 

 life may also be frequently set with advantage. 



The Board of Education also attach considerable importance 

 to the work being done by the elder scholars outside the school 

 walls, whether such work takes the form of elementary mensu- 

 ration, of making sketch plans of the playground and the district 

 surrounding the school, of drawing common objects, ponds» 

 farms, and other suitable places under the guidance of the 

 teacher, or of the cultivation of a school garden. 



The teacher should as occasion offers take the children out o^ 

 doors for school walks at the various seasons of the year, and* 

 give simple lessons on the spot about animals in the fields and . 

 fermyards, about ploughing and sowing, about fruit trees and 

 forest trees, about birds, insects and flowers, and other objects 

 of interest. The lessons thus learnt out of doors can be after- 

 wards carried forward in the schoolroom by reading, composi- 

 tion, pictures, and drawing. 



In this way, and in various other ways that teachers will 

 discover for themselves, children who are brought up in village 

 schools will learn to understand what they see about them, and- 

 to take an intelligent interest in the various processes of nature. 

 This sort of teaching will, it is hoped, directly tend to foster ia 

 the children a genuine love for the country and for country 

 pursuits. 



It is confidently expected that the child's intelligence will be 

 so quickened by the kind of training that is here suggested that 

 he will be able to master, with far greater ease than before, the. 

 ordinary subjects of the school curriculum. 



