of continuous selection in corn for certain special characteristics, including both chemical and physical properties, have been carried on for many years at the Illinois Agricultural Experiment Station. Twenty-four generations of selection to influence the composition of the grain show very marked responses, and from a single original variety four diverse strains have been established, namely, high protein, low protein, high oil, and low oil. Similarly, high- and low-ear strains as well as erect- and declining-ear strains have been produced. Another example of this response to selection has been the development of a two-eared strain from an ordinary single-eared variety. In like manner differences in yield have been induced by similar methods of selection. These results all go to show something of the possibilities of profoundly modifying various characteristics by con

of shelled corn per acre of the F, cross over the better parent has averaged less for the last two years than for the first four years of the tests in the case of crosses with Minnesota No. 13. On the basis of these results it appears that, if corn were selected primarily on the basis of yield, the value of F, varietal crosses would be somewhat questionable.

Rust and the weather: H. L. WALSTER. At Fargo, N. D., blue stem spring wheat averaged 7.1 bushels per acre in 5 seasons when rust epidemics occurred, and 26.7 bushels per acre in 5 nonrust seasons. The average minimal and maximal temperatures by 10-day periods from the date of seeding show the following differences as between the respective 5-year periods:

Average Differences in Degrees F. for Each 10day Period after Seeding. Five-year Averages

First generation corn varietal crosses: FRED GRIFFEE. A brief review is made of the development of the theory which accounts for the increased vigor of F, crosses. Experiments are reviewed in which F, corn crosses are compared with their parents for yield of grain. Of 146 crosses, 113 exceeded the parental average in yield of grain and 84 exceeded the better parent. At the Minnesota station 5 flint-dent crosses tested for a period of two to six years yielded an average of 7.7 per cent. more shelled corn per acre than either parent. Particular attention is called to the cross between Minnesota No. 13 and Squaw Flint which yielded 8.4 per cent. more shelled corn per acre than Minnesota No. 13, which is the higher yielding parent, and was a week to ten days earlier in maturity than Minnesota No. 13. Such a cross appears of considerable promise for sections where early maturity is an important factor. During the first three years of the study a strain of Minnesota No. 13 was used which had been selected for type for several years. In the latter years this strain was selected primarily for yield. The increase in yield

During rust years maximal temperatures rose more rapidly and reached their highest point sooner than in non-rust years. The average rainfall during April, May, June and July averaged higher in rust years than in good years. When high rainfall occurred in good years danger of rust has been offset by low temperatures. When excessively high temperatures have occurred in good years, danger of rust has been offset by droughty conditions. P. E. BROWN, Secretary-Treasurer

Candidates for admission must be graduates of approved colleges or scientific schools with at least two year's instruction, including laboratory work, in Chemistry, and one year each in physics and biology, together with evidence of a reading knowledge of French and German.

Each class is limited to 90 students, men and women being admitted on the same terms. Except in unusual circumstances, applications for admission will not be considered after July 1st. If vacancies occur, students from other institutions desiring advanced standing may be admitted to the second or third year provided they fulfill all of our requirements and present exceptional qualifications.

The charge for tuition is $250 per annum, payable in three instalments. There are no extra fees except for rental of microscope, certain expensive supplies, and laboratory breakage.

The annual announcement and application blanks may be obtained by addressing the

Dean of the Johns Hopkins Medica School Washington and Monument Sts. BALTIMORE, M.D

SUMMER WORK FOR GRADUATES
IN MEDICINE

Beginning Tuesday, June 6th, and ending Thursday, July 16th, a course in medical diagnosis, including laboratory exercises in clinical pathology and demonstrations in pathological anatomy, will be offered. The course will be limited to twenty students, fee $100. Applications should be made to the Dean's Office.

Louisiana

SCHOOL OF MEDICINE

(Established in 1834)

ADMISSION: All students entering the Freshman Class will be required to present credits for two years of college work, which must include Chemistry (General and Organic), Physics and Biology, with their laboratories, and at least one year in English and one year in a modern foreign language.

COMBINED COURSES: Premedical course of two years is offered in the College of Arts and Sciences, which provides for systematic work leading to the B.S. degree at the end of the second year in the medical course.

School of Pharmacy, School of Dentistry and Graduate School of Medicine also.

Women admitted to all Schools of the College of Medicine

For bulletins and all other information, address Tulane College of Medicine

P. O. Box 770

New Orleans, La.

Marine Biological Laboratory

Woods Hole, Mass.

INVESTIGATION Entire Year

INSTRUCTION

une 29 to August 9 1921

SUPPLY
DEPARTMENT

Open the Entire Year

Facilities for research in Zoology, Embryology, Physiology, and Botany. Eighty-four private laboratories, $100 each for not over three months. Thirty tables are available for beginners in research who desire to work under the direction of members of the staff. The fee for such a table is $50.00.

Courses of laboratory instruction with lectures are offered in Invertebrate Zoology, Protozoology, Embryology, Physiology and Morphology and Taxonomy of the Algae. Each course requires the full time of the student. Fee, $75. A lecture course on the Philosophical Aspects of Biology and Allied Sciences is also offered.

Animals and plants, preserved, living, and in embryonic stages. Pre served material of all types of animals and of Algae, Fungi, Liverworts and Mosses furnished for classwork, or for the museum. Living material furnished in season as ordered. Microscopic slides in Zoology, Botany, Histology, Bacteriology. Price lists of Zoological and Botanical material and Microscopic Slides sent on application. State which is desired. For price lists and all information regarding material, address

GEO. M. GRAY, Curator, Woods Hole, Mass.

The annual announcement will be sent on application to The Director, Marine Biological Laboratory, Woods Hole, Mass.

ELECTRIC OVENS

C

THELGO

New type double walled Thelco Oven Automatically controlled.

Moderately priced so that no Laboratory need be without one.