THE SPHAEROBOLUS GUN 327 



dwelling room the Sphaerobolus gun can shoot its projectile from a 

 table to the ceiling. 



A few weeks after making the preliminary observation just 

 recorded, I procured a piece of a board bearing fruit -bodies at 

 Kenora, brought it to Winnipeg, washed it with water, and put it 

 under a bell- jar exposed to the light. Then, each day for about a 

 week, a few fruit-bodies came to maturity and discharged their 

 glebal masses between 10 a.m. and 2 p.m. With this material the 

 range of the Sphaerobolus gun was determined with some exactitude. 



A fruit-body, which was just about to discharge its glebal mass, 

 was placed on a table in the laboratory. The glebal mass was shot 

 upwards to the ceiling and stuck there at a height of 6 feet 10- 5 

 inches above the fruit -body. A sheet of tissue-paper was then 

 attached to the ceiling and the fungus guns were aimed at it from 

 below. Some of the fruit-bodies hit the tissue paper with their 

 projectiles when the vertical distance to be traversed was 7 feet 

 3- 5 inches. The maximum height to which a glebal mass was shot 

 in any of these experiments was 7 feet 8- 5 inches. The glebal 

 masses of five fruit-bodies failed to strike the tissue-paper when 

 the fruit -bodies were 7 feet 9- 5 inches below it. These observations 

 therefore indicate that the vertical range of the Sphaerobolus stellatus 

 guns used in my experiments was about 7 feet 8- 5 inches. 



In order to measure the horizontal range of the Sphaerobolus 

 gun, I took a fruit-body which had opened stellately in a damp- 

 chamber, and set it on a table so that its axis was inclined upwards 

 at an angle of 45° (cf. Fig. 163, 6), and I placed tissue-paper from 6 

 to 12 feet away, on tables of the same height as the first, so that the 

 glebal mass, after its discharge, might land upon it. I watched and 

 waited, waited and watched. At length, after about an hour had 

 passed, the glebal mass was suddenly shot from the gun. As the 

 discharge took place, I heard the snap and saw the inner membranes 

 of the gun become everted ; but the projectile disappeared and was 

 not to be found upon the tissue-paper. However, on searching 

 about, I discovered that the glebal mass had been shot beyond the 

 extreme edge of the sheets of tissue-paper and had lodged upon a 

 flat -topped stand at a distance of 14 feet 1 inch from the fungus gun 

 which had discharged it. The glebal mass was identified by its 



