RESEARCHES ON TIIK MUCORINI. 49 



Researches on the Mucorini, hy Ph. Van Tieghem and 

 G. Le Monnieb (with Plates III and IV).^ 



Since modern research has demonstrated "the existence of 

 polymorphism in the reproductive organs of Fungi, there has 

 been a general agreement as to the necessity of a revision of 

 the entire class. No species of fungus can now be said to be 

 thoroughly understood until all the reproductive structures 

 have been discovered which its mycelium is capable of develop- 

 ing as well as the order in which they succeed one another, 

 or alternate. From being acquainted with but one kind of 

 reproductive apparatus we may easily fall into error in 

 assigning to the species to which it belongs a wrong place in 

 a natural classification. Such a determination must be 

 necessarily provisional, and it is most essential to endeavour 

 to arrive at a knowledge of those other reproductive states 

 which can alone enable us to certainly determine its true 

 systematic position. It may even happen that two species 

 belonging to distinct genera may each have a reproductive 

 apparatus (and this may also happen to be at the time the 

 only one known) which may have so close a resemblance as 

 to all but justify us in regarding them as identical. The 

 number and nature of the reproductive structures which a 

 species posseses cannot be deduced a priori from any general 

 law; in different families of the same class the vegetative 

 cycle may embrace an altogether different series. 



It is evident, therefore, that the study of fungi presents 

 great difficulties which explain the slowness as well as the 

 uncertainty of its progress, and even the retrograde direction 

 it has taken and the confusion into which it has fallen 

 in the hand of some authors. These difficulties are of two 

 kinds, synthetic as well as analytic. The first present them- 

 selves when we attempt to correlate with the species to which 

 it belongs some reproductive structure which we meet with 

 altogether isolated. The others arise when we seek to 

 distinguish amongst the numerous forms which habitually 

 grow mixed together those which have a true genetic 



1 [This article is a free but condensed translation of portions of a memoir 

 occupying nearly 140 pages of the 17th volume (pp. 261 — 399) of the 

 current series of the ' Annales des Sciences Naturelles.' The extremely 

 interesting results arrived at by the authors derive a special importance 

 from the precision of the method which they have devised and employed. 

 It is much to be hoped that this will attract the attention of microscopists 

 in this country, and lead to the repetition and extension of similar observa- 

 tions.— W. T. T. D.] 



VOL. XIV. NEW SER. D 



