212 



SCIENCE. 



[N. S. Vol. III. No. 58. 



plain chalazal impregnation, he points out that 

 the entire course of the pollen-tube of the Gym- 

 nosperms is through tissue. He thinks that in the 

 primitive Angiosperms, the descendants of the 

 Gymnosperms, the tube has not yet acquired 

 the ability to grow across open spaces, and 

 therefore takes the indirect route which enables 

 it to make its whole course through tissue. He 

 also announces that the elm constitutes an in- 

 termediate form between those with chalazal 

 and those with the micropylar impregnation. 



Much work on this line is yet to be done, 

 which may throw light on relationships among 

 flowering plants. 



On motion the meeting adjourned. 



JANUARY 23. 



One hundred and twenty-fourth regular meet- 

 ing, January 23, 1896. President Remsen in the 

 chair. 



The following papers were presented and read: 



1. The Temperature of the Earth's Interior: By 



G. K. Gilbert. 



The speaker first pointed out the difiiculty 

 attending any investigation of the earth's in- 

 terior, and stated that in the present condition 

 of physical science all estimates of interior tem- 

 perature are necessarily founded on question- 

 able postulates. He then gave the results of a 

 series of computations of the average tempera- 

 ture, each starting with a group of postulates. 



'2. The Effect of Pressure on the Wave-Lengths of 



Lines in the Arc-Spectra of Certain Elements : 



By J. F. MoHLEE. 



Mr. Mohler first pointed out that these wave- 

 lengths had been considered as constants, and 

 that it had even been proposed to use them as 

 fundamental standards of length. This was 

 followed by a detailed account of a series of ex- 

 periments carried on in the Physical Laboratory 

 of the Johns Hopkins University, which clearly 

 establish the fact that these wave-lengths vary 

 with the pressure. Pressures as high as twelve 

 atmospheres were used. Diagrams were ex- 

 hibited showing the results of the investigations. 



The following papers of research were then 

 presented and read by title : 



1. On Infinite Products: By A. S. Chessin. 

 (University Circulars : J. H. U.) 



2. Additional Note on Divergent Series : By A. 

 S. Chessin. (Bull. Am. Math. Society.) 

 On motion the meeting adjourned. 



Chas. Lane Poor, Secretary. 



BOSTON SOCIETY OF NATURAL HISTORY. 



The Society met January 1st, forty -three per- 

 sons present. 



Prof. W. O. Crosby and Mr. A. W. Grabau 

 showed that the chief deposits of modified drift 

 in and about the Boston Basin could be referred 

 to a connected chain of glacial lakes along the 

 southern and western borders of the basin. 

 These lakes existed between the receding mar- 

 gin of the ice sheet and the watersheds of the 

 streams tributary to Boston Harbor, and, after 

 the manner of lakes of this class, they were, 

 through the continued recession of the ice mar- 

 gin, somewhat migratory in character and sub- 

 ject to great variations in outline, area, and 

 level. During the period of the maximum and 

 most interesting development of these lakes, 

 the general trend of the ice margin was east- 

 west along the southern border of the basin 

 and north and northwest across the western end 

 of the basin from the western end of the Blue 

 Hills to the highland of Weston and Waltham; 

 the ice, in accordance with the well established 

 principles governing the motion of an ice sheet, 

 having lingered on the depressed areas of the 

 Boston Basin and Boston Harbor after it had 

 disappeared from the relatively high land form- 

 ing the western border of this great trough. 



Along the south side of the basin, in Hing- 

 ham, Weymouth, Braintree, Randolph, and 

 Quincy, was formed Lake Bouve (named in 

 honor of Mr. T. T. Bouv6, a former President 

 of the Boston Society of Natural History), some 

 twelve miles in length. Its diflferent levels, as 

 determined by successive outlets, first south 

 into North River and later east into Cohasset 

 Harbor, were approximately 140 feet (Liberty 

 Plain), 70 feet (Glad Tidings Plain), and 50 feet 

 (Lower Plain). Other glacial lakes were formed 

 in the upper basins of the Neponset and Charles 

 Rivers. At their highest levels (240 to 300 

 feet) these were independent and tributary, 

 respectively, to the Taunton and Blackstoue 

 Rivers. But at the level of 200 feet they were 

 confluent and had a common outlet into the 



