282 CARNEGIE INSTITUTION OF WASHINGTON. 



should be cooperative between scientific workers of that region and the labor- 

 atory in Washington. The plan was favorably received and some excellent 

 work has since been done, but in the meantime it has seemed advisable to 

 make a second, shorter trip over part of the same territory. This was done, 

 April 28 to May 28. Conferences were held with scientists at San Diego, 

 La Jolla, Laguna Bay, Los Angeles and vicinity, including the new station at 

 San Pedro, not yet in operation at the time of the former trip, and the terri- 

 tory about San Francisco. The Puget Sound area was omitted, as the 

 stations there were not yet opened; and Pacific Grove, California, was also 

 left out, as the work there seemed to need no stimulation. An invitation to 

 revisit Lompoc was declined as being unnecessary; but two microscopists 

 from there came to Los Angeles and a day was spent in demonstrating methods 

 of diatom study. While at Los Angeles an illustrated lecture, under the 

 auspices of the Brenner Club, was given to men associated with the Cali- 

 fornia petroleum business on "The probable relation between diatom beds 

 and petroleum deposits." 



The trip brought out the fact that the main difficulty in the way of diatom 

 study on the Pacific Coast is a lack in diatom literature. To somewhat com- 

 pensate for this handicap an offer was made to supply the stations with sets 

 of mounted diatoms representing the common species of the local flora — in 

 other words, authentic types by which most of the diatoms of each locality 

 can hereafter be recognized, further mounted specimens to be added as other 

 forms are discovered. The plan met with approval and will greatly stimulate 

 interest in the work. A set of 48 species has already been made and sent to 

 Dr. W. K. Fisher at Pacific Grove. 



A large amount of diatom material has been distributed during the year to 

 parties interested in their study in this and other countries. The diatom 

 collection at the U. S. National Museum has been greatly improved. 



McCracken, Isabel, Stanford University, California. Studies in silkworm 

 bionomics. 



In the spring of 1920, eggs of five races of silkworms were received at the 

 Stanford Entomological Laboratory from Japan through the courtesy of 

 Mr. M. T. Kagayama, Director of the Imperial Tokyo Sericultural Institute, 

 and Mr. S. I. Kuwana, Director Imperial Plant Quarantine Station, Yoko- 

 hama. 



Italian Alpine, dichromatic as to larval color (zebra and white of so-called normal pattern) 



and buff cocoons. 

 French Sezarl, dichromatic as to larval color (moricaud and white), dichromatic as to cocoon 



color, white and buff (white prevailing). 

 French Lucien, dichromatic as to larval color (zebra and white of the so-called plain type) 



and buff cocoons. 

 Japanese White, white larva of normal pattern and white constricted cocoons. 

 Chinese White, white larva of plain type and white oval non-constricted cocoons. 



On the basis of certain work in silkworm bionomics' carried out by Dr. Kellogg 

 and his students at Stanford University from 1900 to 1912, this material was 

 utilized by the author in 1920-21 and again in 1921-22, in a set of breed- 

 ing experiments designed as follows: 



* 1908, Kellogg and Bell, Inheritance in silkworms: I, Stanford University Publications No. 1; 

 other papers, and much unpublished data. 



