GENERAL SUMMARY 



THE FOLLOWING IS A SUMMARY OF THE MORE IMPORTANT 

 RESULTS OBTAINED DURING THE INVESTIGATIONS 



PART I 



Chapter I. — The history of our knowledge of the discovery, develop- 

 ment, general structure, sexuality, cytology, pigmentation, parasites, 

 drop-excretion, reactions to light, and balHstics of Pilobolus has been 

 reviewed. 



The relation of larval Roundworms (Nematoda) to the fruit-bodies of 

 Pilobolus has been discussed. These animals often swarm up the sides 

 of the sporangiophore but do not penetrate into the subsporangial swelling. 

 Sometimes they travel with a sporangium when this is shot away through 

 the air. 



Syncephalis nodosa van Tiegh., as a parasite on Pilobolus longipes 

 and P. Kleinii, has been described and illustrated. 



Chapter II. — The germination of the spores, the growth of the 

 mycelium, and the formation of fruit- bodies of Pilobolus longipes have 

 been described. 



Spores of P. longipes were sown on fresh sterilised horse-dung balls 

 in a closed crystallising dish, and many of the fruit-bodies which came up 

 on the dung had colourless, instead of black, sporangial walls. This 

 abnormality appears to have been caused by gaseous emanations given 

 off by the horse dung. 



Species of Pilobolus observed at Winnipeg were : P. longipes, P. 

 Kleinii, P. oedipus, and P. umbonatus. 



A series of successive stages in the development of a diurnal crop of 

 fruit-bodies of P. longipes, as affected by external conditions, particu- 

 larly light and darkness, has been represented diagrammatically. 



The maximum vertical height to which sporangia of P. longipes and 

 P. Kleinii were shot was 6 feet 0-5 inch. 



The maximum horizontal range of the fruit-body gun was found to 

 be : for P. longipes, 8 feet 7 -5 inches ; and for P. Kleinii, 8 feet 0-5 inch. 



The structure of the sporangiophore and of the sporangium of P. 

 Kleinii and P. longipes has been described in detail as a preliminary to a 



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