BOTANICAL RESEARCH MACDOUGAL. 133 



Prof. J. J. Thornber has contributed a set of herbarium specimens from 

 southern Arizona to the Desert Laboratory, and has aided the staff at all 

 times in the systematic study of the local flora. He has accompanied several 

 of the field expeditions to various localities and also cooperated in the organ- 

 ization of the alpine plantation. 



Prof. W. P. Blake has contributed a set of the report of the tenth census 

 of the United States to the library of the Desert Laboratory, which is also 

 the recipient of numerous publications given by members of the staff. 



The publications received by the Department, not needed in its work or 

 development have been contributed to the botanical libraries of several insti- 

 tutions. 



By the courtesy of Dr. N. L. Britton, director-in-chief, the facilities of the 

 propagating houses and experimental grounds of the New York Botanical 

 Gardens have been given for the completion of v.-ork on plant breeding by 

 Dr. D. T. MacDougal. Space in the laboratories has also been at the 

 disposal of the Department for work in connection with these investigations. 

 As a partial return for these courtesies the members of the staff of the 

 Desert Laboratory have used every effort to aid in the investigation of the 

 Cactacese by Dr. N. L. Britton and Dr. J. N. Rose, of the United States 

 National Museum. Several shipments of living material from Nevada, 

 Arizona, California, and various places in Mexico have been sent to these 

 investigators. 



BUILDINGS AND EQUIPMENT. 



Some of the facilities of the Desert Botanical Laboratory have been noted 

 in previous reports, but it will be of interest to present here a complete 

 summary of the equipment. 



Reservation. — Beginning with the effort of the Chamber of Commerce of 

 Tucson, in 1903, various additions have been made to the tract on which the 

 Laboratory is located so that at the present time the grounds available for 

 experimental work comprise 860 acres, immediately to the westward of the 

 city of Tucson. Within this tract Tumamoc hill rises to a height of eight 

 hundred feet above the lower mesas. These topographical features present a 

 wide diversity of conditions for vegetation, and offer ideal conditions for 

 many classes of experimental work. The Laboratory building is placed on 

 a shoulder of the hill about midway to the top, and is reached by a mountain 

 road of uneven grade which will shortly be replaced by one of better plan. 

 During the present year the grounds were enclosed by a wire fence of three 

 strands on cedar posts set a rod apart ; it will be necessary, however, to rein- 

 force this fence with a basal section of wire netting of close mesh to exclude 

 domestic animals and to control jack-rabbits and other animals which would 

 injure the increasing vegetation. Within a few months after the completion 

 of this fence the difference between the vegetation and that of the surround- 

 ing areas was noticeable, and also an increased abundance in the number of 



