90 REPORTS O? INVESTIGATIONS AND PROJECTS. 



on belly and primaries. This year the mottled birds were bred together and 

 produced almost exactly one-fourth white birds. The black pigmentation is 

 dominant over its absence, but in the heterozygote does not develop on the 

 belly and the feathers of the extremity of the hand. 



Finches. — The breeding of these birds was in some respects more success- 

 ful than last year, 148 having been reared, an increase of 48 per cent. This 

 success was chiefly due to a slight alteration of the heating system and better 

 night firing. 



Sheep and Goats. — Thirteen sheep and six goats were reared in the various 

 matings. Cooperative work in sheep-breeding has been begun with the New 

 Hampshire Agricultural Experiment Station. 



Cats. — In October, 1908, a new cat-house of concrete blocks was erected, 

 giving four compartments for breeding cats and four for mothers with 

 young. The health of the cats was greatly improved, but they have shown a 

 large degree of sterility in confinement. Nine young were born in the spring. 



Insects. — Dr. Lutz reports as follows : 



From September i, 1908, to March i, 1909, the work with Drosophila was 

 continued along the same lines as in previous years. Considerable breeding 

 was also done with Gryllus, in the greenhouse, in order to continue the long- 

 winged strain brought from Mexico and to cross it with our native crickets. 

 Having accepted a position with the American Museum of Natural History, 

 the work with Drosophila has been continued there with some slight modifica- 

 tion, and a report is now being prepared upon the greater part of it. Through 

 the kindness of the Station the crickets were kept for me at Cold Spring 

 Harbor until the middle of July, 1909. The strains are now being kept at 

 the museum for use in future work, and it is hoped that a report upon the 

 work done with them at the Station will be ready shortly. 



WORK ON PLANTS. 



Dr. Shull, upon his return from his European trip, continued his study of 

 Mr. Burbank's horticultural methods and results, and in the limited time at 

 his disposal at the Station continued the strains of plants upon which he has 

 been at work for the last few years. He reports as follows : 



In the pedigree studies of plants attention has been mainly given, as in the 

 past several years, to the range of applicability of such recently developed 

 conceptions of variation and heredity as are involved in the words "muta- 

 tion," "biotype," "segregation," "unit-characters," "fluctuation," "regression," 

 etc. The cultures have been in unusually good condition, except those of 

 Helianthus and Verbascum, and a small portion of the Lychnis cultures 

 which were taken to a plot of ground at some distance from the Station, 

 which had not been sufficiently fertilized. The effect of this was that the 

 branching which is being investigated in Helianthus was very much reduced, 

 very few of the Verbascwns reached maturity the first season, and the 

 Lychnis remained small and bore relatively few flowers, so that the time 

 within which observations could be made upon them was much limited. 



