46 



SCIENCE 



[N. S. Vol. XLVI. No. 1176 



The specimen, whicli was collected in the coal- 

 bearing beds of the Tokim formation, is about 8 

 cm. in diameter. The symmetrical arrangement of 

 certain meridional and other lines on its surface 

 and attached fragments of what appears to have 

 been an epiearp suggest that it may be a fossil 

 fruit or nut. Other possibilities are suggested. 



A large colony of fossil coral: A. 0. Thomas. 



A coral colony of gigantic proportions was re- 

 cently discovered in a reef of Niagaran corals in 

 Jones county. Conditions under which the colony 

 occurs, its dimensions and associations, are de- 

 scribed. Illustrations. 



Notes on a decapod Crustacean from the Kinder- 

 hook shale near Burlington: Otto Walter. 

 Mississippian crustaceans are comparatively 



rare. An incomplete specimen found imbedded in 



a hard shaly nodule is described. It seems to be 



allied to the old genus Paleopaleomon. 



Some observations on the history of Yangtse 

 Biver, China: C. L. Foster. 



Some geologic aspects of conservation: James H. 



Lees. 



Some of the beauty spots of Iowa are described 

 and their scenic and geologic values are mentioned. 

 The necessity for their preservation is emphasized. 



Some fundamental concepts of earth history: 



James H. Lees. 



After a brief discussion of the evidence for pro- 

 gressive development of the material world there is 

 given an outline of the trend of thought regarding 

 the history of the earth. This outline covers the 

 work of leading thinkers from the Greek and Eo- 

 man philosophers to the great systems evolved by 

 La Place and Chamberlin. 



(o) The Prairie du Chien-St. Peter unconformity in 

 Iowa. (6) The origin of the St. Peter sand- 

 stone, (c) Some conclusions concerning the 

 erosional history of the driftless area: A. C. 

 Tkowbridge. 



Some Economics 

 Improved method for home canning : C. N. Kinnet 



AND Maurice Ricker. 



Suggested use of calcium chloride and other 

 salts in solution in outer vessels of double boilers 

 to raise boiling point in inner vessel. 



Experiments in cooking cereals, canning fruit 

 and vegetables indicate that this cheaper device 

 may replace the auto-clav for these purposes, espe- 

 cially when the inner vessel is subjected to slight 

 pressure. 



■ Physics 



(a) Certain features of rheostat design. (6) A71 

 interesting case of resonance in an alternating 

 current circuit: H. L. Dodge. 



The absence of relationship between electro-me- 

 chanical properties of selenium crystals and their 

 photo-electric emission by ultra-violet light: P. 

 G. Brown and F. S. Tetter. 



The X-ray K-radiation from tungsten : Elmer Dee- 



SHEM. 



The influence of intensity ratio in binaural sound 

 localization : E. M. Berry and C. C. Bunch. 



A peculiar electrically conducting layer on the sur- 

 face of mica : G. W. Stewart. 



On the torsional elasticity of drawn tungsten wires : 

 L. P. SlEG. 



The thermal conductivity of tellurium: Arthur B. 



FORTSCH. 



{a) Electrical capacity of similar, non-parallel 

 plane plates, and its application where the plates 

 are non-rectangular, (b) Mathematics of stro- 

 boscopy; The strobodeik; Theory of the stro- 

 boscopio effect by reflection of light from vi- 

 brating mirrors, (c) Precontact conduction cur- 

 rents: L. E. DoDD. 



Effect of drawing on the density and specific re- 

 sistance of tungsten: Wm. Schriever. 



Effect of gases on unilateral conductivity: Egbert 

 B. Dodson. 



Zoology and Allied Subjects 

 Birds of the past winter, 1916-17, in northwestern 



Iowa: T. C. Stephens. 

 A list of the birds observed in Clay and 'Brien 



counties, Iowa: Ira N. Gabrielson. 

 An annotated list of the mammals of Sac county, 



Iowa: J. A. Spurrell. 

 Bell's vireo studies: Walter W. Bennett. (Il- 

 lustrated with lantern.) 



Observations on Bell's vireo, a species of the 

 central United States which has heretofore been 

 little studied. Near Sioux City it arrives unob- 

 trusively from the south during the second and 

 third weeks in May. During nesting, which imme- 

 diately follows, the bird has been found to sing on 

 the nest after the fashion of the warbling vireo. 

 A tendency of the bird to become easily tamed, a 

 habit of very frequently sitting for long periods in 

 a resting attitude near the nest, and other charac- 

 teristic actions have been noted. Also, an un- 

 usually large proportion of cowbird's eggs in their 

 nests and other facts point to a possible diminish- 

 ing number of indi'i'iduals of the species, at least 

 near Sioux City. 



