The play-equipment necessary for children's life activities in their playing space has long been composed of three typical play-equipments of the swing, the slide and the jungle gym which are generally situated at the children's park. Recently, however, new kinds of the play-equipment have been created and introduced so rapidly and remarkably even as to replace the former three play-equipmets. Such a situation must reflect the fact that more complicated functions than those of the swing, the slide and the jungle gym are requested to the play-equipment at present.
Twenty years ago in Japan there were plenty of natural environment which provided children with various playing spots and playthings such as hills, brooks, the green and insects. Children could find and create their own life by themselves in such natural environment. In twenty years since then, however, such natural open spaces have been gradually almost lost, and the children's park has come to he more and more important as the only one last open space in which children can play safely. Thus along with the environmental change in the children's playing space, the role of the play-equipment itself also has changed in quality. The old playequipments such as the swing, the slide and the jungle gym should no longer remain to play the main role in the children's playing park.
In such a situation, we had to found the scentific method of planning and designing new play-equipments which may fit to the children's life of our age. The motive of this study existed in a fundamental question?“what play-equipments we should create for children?” And, in reality, what is the excellent play-equipment?
Up to the present, the play-equipment has qeen evaluated in the point if it can develop children's excercising ability and physical strength such as sphincterial muscles, grasping power, quickness in action, etc. This tenbency was partially resulted from the fact that the playequipment has been regarded as a kihd of spoting goods. Against such a conventional thought, this study proposes quite a new point of view that the play-equipment should be evaluated in the point how it can influence children to form group-activity through plaing.
What is most essential for the children's playing environment at present? And, I consider the play-equipment posesses the potentiality of working to induce children to form group activity. So I attempted to analyse and evaluate the play-equipment in the point how it plays the role of forming a community of playing, to be more explicit, how it brings forth a game to children.
The play-equipment is classified to three groups.
I. Old typical play-equipments as usually situated at the park
II.Typical wooden play-equipments of goreign countries.
III. New play-equipments
By giving five examples in each group, I observed fifteen ply-equipments in the points of children, s playing behavior and how a play-equipment develops children's playing. The locations of these examples varied from community parks, kindergartens to the roof of department-store. Therefore, it was impossible to compare them under the equal conditions, which left this study at an introductory stage. I think, however, the method of evaluation itself, how the playequipment works to form children's community of playing, must provide full universal validity After the observation, following results were gained.
1. The children's play with the play-equipment occupies 1/4 ratio of the whole children's play.
2. In the play with the play-equipment, three levels of development are found; (1) mechanical level, (2) technical level and (3) social level. At the social level, a game takes place.
3. Games taking place with the play-equipment are divided to four types; (1) imparsonation game (using the play-equipment as the stage) (2) wrestling game (3) competition game (4) chase game Chase games are found most among all.

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Roses are propagated from seeds, cuttings and usually grafts. In the previous methods of culturing parent stocks, the stocks were so thin and had so much shoots that scions were inserted difficultly.
Having researched since 1968, I have got the good result of the better culture of the stock:
(1) to culture the stocks in the dark to be grown thick,
(2) to be seeded early in February in a greenhouse (20-25°C)
(3) for the soil in the bed to composed of dried red soil 1: Asake sand 1: and dung of cows 1 covered with soil (4mm) and chaff Kuntan (6mm)

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[in Japanese]

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The purpose of this study is to present green potential concept and to show analytical and synthetical method in reference to the distributional structure of grren spaces by using green potential model.
In Fig. 2, green potential at the point of 0 is assumed to be defined by (g_i; r_i), where gi is a sort of conditiohal value determined by the quality and quantity of green space I, ri is the distance from I to O, and g_i; r_i is potential impact of green space I at thedistance of ri. Most simply, the value of present green condition in mesh M_i'j' represented as a_i'j' is able to be expressed as either I or O, where 1 is in the condition of satisfaction and O is in the condition of unsatisfaction at the standpoint of remarking effect.
One of the most simple green potential model in p step on mesh M_ij is defined as follow,
_??_
where d means the value of numerator on the assumption that ai'j' is always 1.
The distributional type of green spaces can be classified as isometric and anisoutetric (Fig. 1). If it is anisometric as shown in Fig. 5 or Fig. 7 (matrix of green condition), there usually appears the grouping meshes where green potential values are greater or smaller asshown in Fig. 6 or Fig. 8 (matrix of green potential GX2_ij^p). From this, we can obtain not only knowledge about the present distributional structure, but also informations refering to planning of green spaces.

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Studies were made on the threshold temperature and thermal constants for the development of cotton leaf roller, Natarcha derogata FABRICIUS. The results are summarized as follows:
The threshold low temperature for development and total effective temperature were calculated from the result of rearing throught all stages as shown in the next table.
The relationship between developmental velocity (V) and temperature (T) was expressed as following liner equation.
EggV=0.0176 T-0.1805 Larva V=0.0038 T-0.0828 Pupa V=0.0075 T-0.0828 All stages V=0.00224T-0.02642
Under the constant environmental condition of 25°C and 75-90% humidity, the larvae were reared separately on fresh leaves of the Firmiana platanifolia SCHOTT et ENDLE. The larva passed through 6 instars in a generation, and the mean width of head capsule ranged from 1st to 6th instar as 0.24, 0.41, 0.76, 1.23, 1.9, 2.23mm respetively. And the ratios of the same width between succeeing instars were similarly 1. 71, 1.85, 1.62, 1.37 and 1.32.
The relations of log-width of exuviae of head capsule to instar number were found to berepresented generally by two straight lines intersecting at a point of the 4th instar. The larval instar (X) was related to the head capsule width (Y) by the following equation.
lst-4th instar: log Y=2.14+0.24X 4th-6th instar: log Y=2.573+0.13X

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The major purposes of this paper are:
1) to clarify the influence caused by the investment of city park development works
2) to make clear how the investment can contribute to regional development, and
3) to present a new system of city parks and to propose new policies in order to promote economic development of the region and to increase the demand for construction materials. The method employed here is to grasp the multiplier effect of city park works through the analysis of construction documents and the use of the inter-industry relations tables. The multiplier effect is also analyzed by comparing other public works such as road construction, riparian works and swerage and water supply works.
Regarding economic influence of city park development, following points are considered to be important:
1) City park development requires a great variety of construction materials.
2) Construction materials differ according to the type of city park works.
3) The impact of city park development is greater than that of other public works.
4) Labor cost is relatively high.

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