CHAPTER III 



THE SPHAEROBOLUS GUN AND ITS RANGE 



Introduction — The Species of Sphaerobolus — Cultures — The Germination of the 

 Gemmae and of the Spores and the Diploid Nature of the Germ -tubes — The 

 Projectile — The Structure and Mechanism of the Gun — The Range of the 

 Gun — The Range of Sphaerobolus stellatus of Kenora Origin — Miss Walker's 

 Observations on the Range of Various Sphaeroboli — An Artificial Method for 

 causing a Sphaerobolus Gun to discharge its Projectile — The Horizontal Range 

 of Sphaerobolus stellatus of Winnipeg Origin — Summary of Observations on 

 the Range of Sphaerobolus Guns — The Horizontal Range of Various Fungus 

 Guns and of Expulsive Fruits — The Kinetics of the Sphaerobolus Gun — 

 Relations of Sphaerobolus with Water — Relations of Sphaerobolus with Light — 

 Sphaerobolus as a Coprophilous Fungus dispersed by Herbivorous Animals — 

 Pilobolus, Ascobolus immersus, and Sphaerobolus as Three Fungi with Parallel 

 Adaptations for a Coprophilous Mode of Life— Sphaerobolus as a Member of 

 the More Specialised of Two Groups of Coprophilous Fungi— Sphaerobolus as 

 a Lignicolous Fungus and the Problem of its Mode of Infecting Wood. 



Introduction. — Sphaerobolus is a genus of the Gastromycetes, which 

 includes an uncertain number of species and is of world-wide distri- 

 bution. Its very delicate and wonderfully constructed fruit-bodies 

 are commonly found in Europe and North America in groups upon 

 rotting wood and sometimes on the dung of herbivorous animals. 

 I myself have observed the fungus : in England, on old stumps, 

 boards, sticks, sacking, and a fallen cone of Cedrus Deodara ; and, 

 in central Canada, on a board and wooden post lying on the ground, 

 and on cow-dung and horse-dung plats scattered in meadows. 



In the island of Trinidad, according to Rorer, 1 Sphaerobolus 

 stellatus is found commonly on cow dung ; and in New Zealand, 



1 J. B. Rorer, " A Preliminary List of Trinidad Fungi," Board of Agriculture for 

 Trinidad and Tobago, Circular No. IV, Report of the Mycologist for the year ending 

 March 31, 1911, Part II, issued Oct. 1911, p. 42. 



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