SCIENCE- GOSSIP. 



quoted in Mr. Howard's article, of a long series of 

 experiments of all kinds, it would appear as though 

 the most successful results had been obtained from 

 the use of the heavier grades of kerosene. 



It will be seen that there is yet much to be done 

 in this group respecting, first, the correct classifi- 



cation of the world's sxaecies ; secondly, the in- 

 vestigation of the life history of the various species, 

 at present only that of perhaps a score being' 

 known : and thirdly, the discovery of effective reme- 

 dies against their undesirable attacks on mankind- 

 London. May 1901. 



THE MYCETOZOA. 



By Edgar Saunders. 



rTlHE curious group of organisms usually known 

 -*- as Mycetozoa forms one of the numerous 

 links that connect the animal and vegetable king- 

 doms. They frequently occur as denizens of damp 

 w r oods, where they creep about during one stage 

 of their existence on rotten logs or fallen branches. 

 They are also to be found on decaying heaps of 

 leaves or straw, especially if such accumulations 



more vacuoles. They can throw out a tail-like 

 process, and also possess the power of locomotion. 

 In this state they are known as swarm-cells, and 

 so simple is then structure that any part of them 

 may become a mouth, a stomach, or a foot. By 

 the coalescence of numbers of these and their in- 

 crease by partition a mass is formed of wall-less 

 protoplasm varying in dimensions. This is called 



Plasmodium of Choxdrioderma radiatum. (From Nature.) 



have been undisturbed for several months. In 

 these situations they are occasionally to be met 

 with in immense quantities, so much so that 

 portions of the heap appear as though covered 

 with hoar-frost, from the numerous calcareous 

 sporangia that have been formed on them. 



The life history of the Mycetozoa presents a 

 series of metamorphoses that are somewhat 

 analogous to those which may be observed in 

 other departments of animated nature. What may 

 be regarded as the initial stage is a spore, always 

 minute and usually spherical. These exist in vast 

 numbers in the atmosphere, and when they fall 

 into favourable situations the minute speck of 

 protoplasm contained has the power of throwing off 

 its cell covering, when it resembles an amoeba. 

 These amoeba-like cells usually contain one or 



Plasmodium, which like the swarm-cells possesses 

 the powers of locomotion and assimilation. This, 

 the feeding stage, is usually the most fascinating 

 to the observer, as the individuals have the power 

 of moving over a considerable surface in search of 

 food, and in this state exhibit affinities with the 

 animal kingdom. 



The Plasmodium stage also serves to distinguish 

 this group from the fungi, with which it is usually 

 associated in classification. Having found some 

 decayed wood or living fungi (Stereum, etc.) suit- 

 able to its wants, it spreads itself over the sub- 

 stance from which it extracts nourishment, and 

 also absorbs any microbes that may be present. By 

 the absorption of these materials it increases in size. 

 In some cases, as in Crateruim, the Plasmodium is 

 of a dirty grey hue, which shade is partly owing to 



