REMARKS ON THE PILOBOLIDAE 179 



wild at Winnipeg, and of Pilaira anomala and P. Moreaui sent to 

 me from Baarn. 



Piloboli commonly occur on horse dung, cow dung, etc., and are 

 so different in appearance from all other fungi and discharge their 

 black sporangia with such vigour that most mycologists have seen 

 one or more of them and have recognised them for what they are. 

 On the other hand, Pilairae are comparatively rare, may easily be 

 mistaken by the uninitiated for Mucors, and have been less often 

 found and studied. Hence perhaps it is that Fitzpatrick ^ in his 

 recent book on the Phycomycetes, after remarking that " at least 

 four species of Pilaira, all of them from dung, have been described " 

 adds : " The possibihty that they were based on abnormal material 

 of Pilobolus leads the writer to regard the genus as somewhat 

 doubtful." From my own comparative studies of Piloboli and 

 Pilairae, I have become convinced that the genus Pilaira is a good 

 one. In the next Chapter the characteristics of Pilobolus and 

 Pilaira have been set forth in detail. 



Anderson ^ has recently taken the trouble to demonstrate the 

 stabiUty of the genus Pilaira by means of a sj^ecial investigation. 

 He made monosporous cultures of Pilaira anomala and found that 

 they remained true and did not give rise to a Pilobolus form. 

 Further, he fed two rabbits, one with lettuce bearing Pilaira 

 sporangia and the other with lettuce bearing Pilobolus sporangia. 

 The dung of each rabbit produced the respective fungus only. As 

 a result of these experiments Anderson concluded that the genus 

 Pilaira van T. is a vaUd one. 



Our knowledge of the Pilobohdae is not as satisfactory as it 

 should be. A number of species, more especially of Pilobolus, have 

 been imperfectly described and illustrated. What is now required 

 is that some systematist should take up the study of the Pilobolidae 

 with a view to preparing a monograjih upon them, based on a 

 comparison of as many species as could be brought together in a long 

 term of years. The resources of photomicrography, unknown to 



^ H. M. Fitzpatrick, The Louver Fungi, Phycomycetes, New York, 1930, p. 253. 



^ R. S. Anderson, " Tlie Validit}' of the genus Pilaira," University of loiva 

 Studies, Vol. XV, 1933, pp. 3-5. Cited from Journ. Roy. 3Iicros. Soc, Ser. Ill, 

 Vol. LIII, 1933, p. 284. 



