no Natural History Bulletin. 



the tropics and some even from the arctic zone. Schroeter 

 found Pkysancm cineremn at North Cape. Our Iowa forms 

 are most numerous in the eastern, that is the wooded regions 

 of the state. I have, however, found Physannn cinereum on 

 the untouched prairie, as also Physarum conlextum on the 

 decaying stems of Calamagrostis. 



As to the economic importance of our Myxomycetes there 

 is no long chapter to wa-ite. The kindly Fries who has a 

 good word to say for almost every living thing, says: *' Usu 

 in vita communi parum adraodum sese commendant, sed in 

 oeconomia naturae certe non spernendi. Multa insectorum 

 genera ex eorum sporidiis unica capiunt nutrimenta." How- 

 ever this may be, there is one species which has come to Hght 

 since Fries' day which is the source of no inconsiderable mis- 

 chief to the agriculturist. PlasmodijfJiora hrassiccE occasions 

 the disease known as the "club-root" in cabbage and has recent- 

 ly been made the subject of special discussion in the yournal of 

 Mycology.'^ Further than this; if Plasmodium malar ice- be 

 indeed a Slime-mould, and be as is alleged, the promoting 

 cause and agent in malarial fever, then the group entire sud- 

 denly springs to most unusual interest in the attention of all 

 mankind. 3 Aside from the injurious tendencies possible or real 

 of these two, I know not that all other Slime-moulds of all 

 the world, taken all together, affect in any slightest measure 

 the hap or fortune of man or nation. And yet, if in the 

 economic relations of things, man's intellectual life is to be 

 considered, then surely come the uncertain Slime-moulds, with 

 their fascinating problems, proffered still in forms of unap- 

 proachable delicacy and beauty, not without inspiration. 



The Myxomycetes are defined and sub-divided as follows: 



1 See Journal of Mycology, Washington, D. C, Vol. VII, No. 2. 



2 See inter al. U. S. Senate Misc. Doc, Report on Cholera in Europe and 

 India, p. 6S8, et seq. 



