A BIOLOGICAL FARM. 223 



Water is the first essential, and three forms of this element are 

 needed, namely, sea water, brackish water, and fresh water. All 

 three forms abound at Wood's Holl and vicinity. The fresh- 

 water ponds are numerous, and many of them, both on the main- 

 land and on the neighboring islands, are completely isolated and 

 stocked with forms in-bred for centuries. Brackish water in 

 almost every degree, pure sea-water and tide-currents are right 

 at hand. 



Land is the next essential, and here we have hill, plain, marsh, 

 swamp, shore and islands, and some of these islands are inimitable 

 biological farms of nature's own make. 



A seasonal range of temperature is essential to the existence of 

 a majority of the forms best suited to cultivation and study ; and 

 in this are supplied very important conditions for experimental 

 work. The surrounding sea protects Wood's Holl from the ex- 

 tremes of heat and cold. 



Isolation. The most favorable combination of conditions may 

 be utterly worthless, unless the farm can be made secure in its 

 isolation from the public. Its work must go on in a quiet en- 

 vironment, where all the conditions are under control, and the 

 investigator is free from the danger of intrusion. 



Mode of Development. The work should be developed slowly, 

 section by section, each section consisting of a group of related 

 species, or a single species, offering a wide range of problems. 



Each section should be in charge of a director, prepared to 

 continue the work during life, and supported by assistants and 

 help for all routine and mechanical service. The staff would 

 consist of directors, assistant investigators, artists, photographer, 

 clerical help, keepers and a business manager. 



Outlay and Maintenance. The original outlay for land, stock, 

 buildings, equipment, inclosures of land and water for isolation 

 purposes, would vary according to the forms selected for study. 

 From $50,000 to $100,000 would suffice for this. The main- 

 tenance of the first section, including salaries, accessions to stock, 

 library, etc., may be estimated at $10,000 a year. The cost of 

 additional sections would be about $5,000 each. 



Ideal Center. The association of three such institutions as the 

 Marine Biological Laboratory, the U. S. Fish Commission Sta- 



