80 



SCIENCE 



[N. S. Vol. LIV. No. 1386 



other conditions which are however of secon- 

 dary importance. As a requisite, the precipi- 

 tate formed must be permeable to the liquid 

 solution used ; in this case the silver nitrate. If 

 for example, lead acetate be used instead of 

 silver nitrate no ring formation occurs, be- 

 cause the lead chromate under these condi- 

 tions is impervious to lead acetate. Not only 

 is it impervious to lead acetate but if silver 

 nitrate replace the solution of lead acetate 

 after the precipitate of lead chromate is 

 formed, silver nitrate will not penetrate the 

 lead chromate wall, and no ring formation 

 will occur. For the same reason if the silver 

 nitrate and potassium bichromate solutions 

 are reversed, no ring formation will occur. 

 Hugh McGuigan 

 College or Medicine, 

 University of Illinois 



THE NORTH CAROLINA ACADEMY OF 

 SCIENCE 



The twentieth annual meeting of the North 

 Carolina Academy of Science was held on April 

 29 and 30, 1921, at "Wake Forest College, Wake 

 Forest, N. C, with about 50 members present, 

 and the following program was carried out. 



Presidential address. The age of insects, Pro- 

 fessor Z. P. Metcalf, State College. 



The genus Easpaillia and the independent vari- 

 ability of diagnostic features: H. V. "Wilson. 



Current research in organic chemistry at the 

 University of North Carolina: A. S. "Wheeler. 



Judgments of length, mass and time: A. H. 

 Patterson. 



A photometric study of the fluorescence of iodine 

 vapor: "W. E. Speas. 



Some fungi new to North America or the 

 Sorith: "W. C. Coker. 



Breeding results from overwintering cocoons of 

 the Polyphemus moth: C. S. Brimlet. 



On the polyemhryonic development of the para- 

 site, Copidosoma gelechiae Howard: E. "W. Leiby. 



Neiu North Carolina gall types: B. W. "Wells 



The Lorentz transformation in Einstein rela 

 tivity: Archibald Henderson. 



Solid culture media with a wide range of hy 

 drogen and hydroxyl ion concentration: F. A 

 "Wolf and I. V. Shunk. 



Notes on the ecology and life history of the, 

 Texas horned lizard: J. P. Givler. 



Ionizing potentials of gases by negative elec- 

 trons: A. A. Dixon. 



An interesting anomaly in the pulmonary veins 

 of man: "W. C. George. 



The inheritance of economic qualities in cotton: 

 R. Y. "Winters. 



Questions arising from the discovery of occas- 

 sional vertebrate hermaphrodites, with a demon- 

 stration of a ease in a pig: Harley N. Gould. 

 (Lantern.) 



The artificial incubation of turtle eggs: Bert 

 Cunningham. (Lantern.) 



Effects of desiocation on cotton seeds and the 

 seed-borne element of cotton anthracnose: S. 0. 

 Lehman. 



The anatomy of Angiopteris: H. L. Blomquist. 

 (Lantern.) 



Tlie electron, its measurements and applications: 

 J. B. Derieux. (Lantern.) 



Further studies on the pure culture of diatoms: 

 Bert Cunningham and J. T. Barnes. (Lan- 

 tern.) 



Aphidius, a parasite of the cotton louse: H. 

 Spencer. 



From egg to frog in two months : H. V. "WiLSON. 



Some considerations in defense of the general 

 biology course: J. P. Givler. 



Some questions concerning the teaching of 

 physics in North Carolina: C. "W. Edwasds. 



Notes on the salamanders of the Cayuga Lake 

 Basin, N. Y., with reference to eggs and larvce: 

 Julia Moesel Haber. 



A more remarl^able shoot: "William F. Proutt. 



Helationship of temperature and relative hu- 

 midity to the distribution of cociroaohes : "V. R. 

 Haber. 



Becent views on the nutritive properties of 

 milh: J. O. Halverson. 



Notes on recently discovered Miocene whale: 

 "William F. Pkouty. 



A method of differentiating mucous and serous 

 cells: Miss E. G. Campbell. 



demonstrations 



Metomiorphosed frogs (Chorophilus) , reared 

 from artificially inseminated eggs in two months: 

 H. V. "Wilson. 



New North Carolina galls: B. "W. "Wells. 



Shells of Baleigh turtles: C. S. Brimlet. 



Examples of Fulgoridce : Z. P. Metcalf. 



At the business meeting President Metcalf an- 

 nounced that affiliation with the American Asso- 

 ciation for the Advancement of Science has been 

 completed except for official notice from the Per- 

 manent Secretary of the Association. 



The following ofiicers were elected for the en- 

 suing year: president, Jas. L. Lake, professor of 

 physics, "Wake Forest College; vice-president, Dr. 

 J. H. Pratt, state geologist; secretary-treasurer, 

 Bert Cunningham, professor of biology. Trinity 

 College ; additional members of the Executive Com- 

 mittee, H. E. Totten, University of North Carolina, 

 R. N. "Wilson, Trinity College, and F. A. "Wolf, 

 State College. 



C. S. Brimley, 

 Acting Secretary 



