THE LARCH CANKER 21 



from the bark '. (iv) The disease occurred most frequently 

 in damp situations, (v) Berkeley observed that the Peziza 

 also occurred on many dead branches and on branches that 

 had been left on the ground after thinning. 



Recent authors have commonly lost sight of the fact that 

 canker was first attributed to its true cause by an English- 

 man, and Berkeley's article has often been ignored by 

 writers who have taken their descriptions from the more 

 detailed papers of the German professors Willkomm and 

 Robert Hartig. Willkomm's * treatise, published in 1867, 

 is, for the time at which it was written, a remarkably full 

 account of the parasitology and pathology of the disease. 

 But it is marred at the outset by an inaccuracy in nomen- 

 clature, which he would have avoided had he been acquainted 

 with Berkeley's article. His description and figures leave 

 no doubt that he was studying the fungus Dasyscyplia 

 calycina, but he confused this species with another fungus, 

 Corticium amarpkum? a Basidiomycete, belonging to an 

 entirely different group of fungi, which has a superficial 

 resemblance to Dasyscyplw and may sometimes be found 

 growing with it. If this error in nomenclature be corrected 

 throughout the paper, the reader will find an accurate 

 record of much that was not previously known about the 



1 Moritz W. Willkomm was born June 29, 1821, at Hewigsdorf near 

 Zittau. He studied medicine and science at Leipzig. He travelled over 

 a, great part of Europe, taking a special interest in field botany, and wrote 

 extensively- on the flora of Spain and Portugal. He took his Ph.D. at 

 Leipzig in 1850 and remained there as a Privatdozent. In 1855 he was 

 created extraordinary professor and custodian of the herbarium. Soon 

 after he was appointed professor of biology in the Forstakademie at 

 Tharandt, where he remained till 1868, when he proceeded to Dorpat as 

 director of the botanic garden. In 1874 he went to the German university 

 at Prague and stayed there till 1893, when he retired. He died in Bohemia 

 in 1898. Willkomm is chiefly known for his writings on the flora and 

 ecology of Spain and Portugal, but he published papers on many other 

 botanical subjects. His Microscopischen Feinde is, as far as I am aware, 

 his only contribution to pathology (vide Allg. Deutsche Biographie, Bd. 43, 

 1898). 



- Hoffman (1868) was the first to call attention to this error. He 

 correctly named the fungus Peziza calycina. 



