90 



SCIENCE 



[N. S. Vol. LII. No. 1334 



A table of the total numier of stroloscopia veloc- 

 ity curves for any of the natural numVers from, 

 1 to 500 inclusive taken as a limiting vahw of 

 n and m: L. E. Dodd. 



On finding the equation of the characteristic black- 

 ening curve of a photographic plate: P. S. Hel- 



MIOK. 



Tlie overtones of air columns: L. B. Spinney. 

 The stereoscope in teaching physics and geometry: 

 LeEoy D. Weld. 



The stereoscope has usually been considered a 

 mere toy. In this paper, however, is given a 

 method whereby etereoseopie drawings of any 

 simple figure dn space can be easily prepared and 

 duplicated for use in the study of any subject re- 

 quiring three-dimensional figures, such as solid 

 geometry, crystal structure, analytic mechanics, 

 optics, etc. 



Psychology 

 Symposium: Some Results of Current Research in 

 the Psychological Laboratory of the State Uni- 

 versity. Introduced by C. E. Seashore. 

 The talent survey in our music school: Esther 



Allen Gaw. 

 The Iowa pitch range audiometer : C. C. Bunch. 

 The normal curve of acuity in hearing: Paul B. 



Andeeson. 

 The localization of sound by wave phase in the 



open ear: Henry M. Halverson. 

 What constitutes voice: Carl I. Erickson. 

 The application of the Mendelian law to talent in 



music: Hazel M. Stanton. 

 The personal equation in motor capacities: Martin 



L. Reymert. 

 Serial action as a basic measure of motor capaci- 

 ties: 0. P. Hansen. 

 The measurement of motility in children: Lillian 



Tow. 

 The selection of talent for stenography and typing : 



B. W. Robinson. 

 A measure of capacity for acquiring skill in co- 

 ordination of eye and hand: Wilhelmine 



KOERTH. 



A standardized measure of motility: Merrill J. 



Ream. 



Zoology 

 Some Iowa records of Lepidoptera : A. W. Lindset. 

 A biological reconnaisance of Okefinokee swamp, 



Georgia. The fishes: E. L. Palmer and A. H. 



Wbiqht. 



The Okefinokee swamfp in its fish fauna is de- 

 cidedly fluviatile. Like that of Florida its fish 

 fauna may be held to have "originated from the 

 north and is thus not tropical. ' ' The swamp has 

 twenty -(three less fresh water species than the whole 

 state of Florida and in number of forms is not 

 comparable to the better known Everglades of 

 Florida. Twenty-eight species are known from the 

 swamp and twenty-two of these are included in the 

 collection upon which this paper is based. Sixty- 

 three specimens of the rare Lucania ommata 

 (Jordan) were taken. The southern limit of the 

 range of Umbra limi (Kirtland) is increased from 

 North Carolina to southern Georgia. In addition 

 the material supports contentions that Umbra 

 pygmcea DeKay is a synonym of Umbra limi 

 (Kirtland) ; Esox vermiculaius Le Sueur, of Esox 

 americanus (Gmelui.) ; Enneacanthus gloriosus 

 (Holbrook), of Enn^eacanthus obesus Baird; and 

 Copelandellu^ quiescens (Jordan), of Boleiohthys 

 fusiformis Girard. 

 Bird records of the season 1919-19S0 in the vicinity 



of Iowa City : Dayton Stoner. 

 Cladocera of the Okoboji and Spirit Lake regions: 



Frank A. Stromsten. 

 Copepoda of the Okoboji region: Frank A. 



Stromsten. 

 Rotatoria of the Okoboji region: Dwight C. En- 

 sign. 

 Similarities between the lateral-line systems of 

 elasmobranclis and amphibians: H. W. NORRIS. 

 Naked neuromasts in amphibians correspond to 

 pit-organs and canal-organs in the elasmobranch 

 fishes. The mandibular series of neuromasts of 

 amphibians is distinctly double, oral, and gular. 

 Similarly in elasmobranchs the mandibular and 

 hyomandibular canal organs correspond to the oral 

 series and a mandibular row of pit-organs to the 

 gular series of neuromasts of amphibians. The 

 vaguely defined occipital group of neuromasts of 

 amphibians corresponds to the sense-organ of the 

 supratemporal canal. Three lines of neuromasts 

 occur on the trunk of the body in amphibians, in- 

 nervated by three distinct nerve rami. Three series 

 of lateral-line organs are to be found on the trunk 

 in elasmobranchs. 



Susceptible and resistant phases of the dividing 

 sea-urchin egg when subjected to various concen- 

 trations of lipoid-soluble substances, especially 

 the higher alcohols: Francis Marsh Baldwin. 

 AVhen subjected to suitable concentrations of 

 various lipoid-soluble substances the developing sea- 

 urchin egg shows unmistakable rhythms of sus- 



