548 



SCIENCE 



[Vol. LV, No. 1429 



elongate. The context is brown and is continued 

 into the trama unchanged. Spores are light- 

 brown, oval. The name Inonotus Schini n. sp. is 

 proposed. The infection results from frost and 

 wind storm injury and from improper pruning 

 methods. Histological studies indicate that the 

 fungus has few if any new features in connection 

 with the development of the club and the basidio- 

 spores. 



Some aspects of the use of the annual rings of 

 trees in climatic study: A. E. Douglass. The 

 ring is primarily a climatic effect. Surplus rings, 

 which are rare, come from too great seasonal em- 

 phasis. Missing rings come mostly from excessive 

 dryness of climate. These errors are readily 

 located by comparing many trees together from the 

 same region. The number of trees so far used is 

 about 450 and the number of rings whose date of 

 growth has been identified is over 100,000. The 

 sequoias of California carry an excellent record 

 for more than 3,200 years. The growth of dry 

 climate trees depends on the topography which 

 controls their water supply. Automatic measur- 

 ing instruments and an analyzing instrument have 

 been constructed. In dry climates the trees show 

 variations which match the rainfall with remark- 

 able exactness. In certain wet climates they show 

 variation that corresponds to the solar activity as 

 denoted by the number of sunspots. The sunspot 

 cycle of 11 years is very common, together with 

 its multiples, 22 and 33 years. The rings of 

 trees are now giving us important information in 

 the chronology of the prehistoric rmns of the 

 Southwest. 



The life history of a pine tree as read from a 

 longitudinally "bisected trmik: Forrest Shreve. 

 A vigorous individual of Pinus radiata 38 years 

 of age was felled and the trunk cut away so as 

 to expose a median longitudinal section. Trans- 

 verse sections were taken at intervals of one 

 meter. The annual rings were then identified 

 and dated in each cross section, using the longi- 

 tudinal surfaces to confirm the dating. Measure- 

 ments of the individual rings were made at each 

 of the transverse sections, showing a very con- 

 siderable irregularity in the thickness of the layer 

 of wood laid on in any one year at different 

 heights on the trunk. The period of most rapid 

 growth in height and diameter was between the 

 ages of 7 and 14 years and between the heights of 

 3 and 8 meters. There is a tendency for the 

 growth in diameter to be greater toward the top 

 of the tree than toward the base. There was a 

 marked slackening in growth rate after the 



thirty-fourth year. Double rings of growth are 

 frequently formed in a single year, due to the 

 resumption of growth in the autumn, and they 

 can usually be readily distinguished from the 

 growth rings of successive years. The autumnal 

 thickening also varies with height and is some- 

 times recognizable at certain heights and appar- 

 ently absent at others. The results indicate that 

 in Finns radiata a true measure of the annual 

 growth performances should be based on several 

 cross sections at different heights and not on data 

 from the stump section alone. 



Effect of tree transpiration on the ground- 

 water table: G. E. P. Smith. Some efforts mad« 

 primarily to determine output of groundwater 

 supply through transpiration seems to offer a new 

 method of learning much concerning the quantity 

 and character of transpiration of phreatophytes. 

 Output method of measuring safe annual yield of 

 groundwater useless without knowledge of trans- 

 piration of forests and botanical literature silent 

 on this subject. Investigations began in 1916 

 but discontinued until 1921. Full year's record 

 in 1921 in mesquite forest and in eottonwood 

 forest. Well pits excavated in selected locations 

 and equipped with water-stage recorders of two 

 types. Movements of water table in winter very 

 slight, but correlate closely with daily barometric 

 cycle and with approach and departure of storms. 

 Budding period shows little effect but, after leaves 

 start, draught on groundwater very pronounced. 

 Daily cycles in fair weather uniform, and of two 

 parts — the daily transpiration curve and nocturnal 

 recharge curve, with very little lag. Effects of 

 cloudiness, rains, warm evenings and other con- 

 ditions plainly marked. Transpiration from mes- 

 quite forest almost ceased in August due to dis- 

 ease of trees which caused defoliation, but be- 

 came rapid again in October after growth of new 

 leaves. 



Changes in the composition of Salton Sea with 

 an interpretation: A. E. Vinson. The series of 

 annual analyses showed that CaCO had not con- 

 centrated as rapidly as total solids. This loss 

 took place as a deposition of tufa. Phosphorus 

 practically disappeared from the water and an 

 analysis of the tufa showed that this may have 

 been deposited with the tufa. Potassium has not 

 concentrated as rapidly as sodium but the potas- 

 sium in the tufa would account for not over three 

 per cent, of that lost. The conclusions drawn 

 are that most of the potassium had been absorbed 

 in the heavy mud deposits to be seen on the 

 shores. 



