THE MYCETOZOA OF THE EAST RIDING. 

 By T. PETCH, B.Sc, B.A. 



IT is generally supposed that Mycetozoa are extremely 

 rare objects. Even Professors of Botany, when ques- 

 tioned by students who wished to extend their knowledge 

 of the group beyond the well-known caricature of Arcyria 

 punicea which illustrates the subject in so many text-books, 

 have been known to warn them that specimens are rarely 

 met with, and to point out the futility of any attempt. 

 Yet there is no group more generally distributed. In 

 town parks, in woods, along country hedges, on dock 

 quays, and in timber yards, wherever any dead vegetable 

 matter can be found, there will also be myxos. 



The majority are certainly minute. This objection was 

 once raised by a botanist during a visit to Epping Forest, 

 but, unfortunately for his argument, we immediately 

 encountered an oak log on which grew several specimens 

 of Reticuhxria Ivcoperdoii measuring from two to seven 

 inches in diameter. But, neglecting these larger forms, the 

 others are not hard to find, since they usually grow in large 

 numbers. There is no difficulty in perceiving a square yard 

 of Cribraria argillacea on the floor of a pine wood, or a six- 

 foot length of Badhamia populina on a fallen log, or a 

 rubbish heap whitewashed with Diachea elegans. The key 

 of the secret is, that to find myxos one must look for myxos : 

 he will never succeed in finding many while he is looking 

 principally for something else. 



The species enumerated in the following list — I regret 

 that through unexpected circumstances it is merely a list — 

 were obtained during the vacations of two years. Thus it 

 has not been possible to make any investigations at what is 

 the best time of year, viz., September to December, and 

 consequently many common leaf-inhabiting forms have not 

 been observed. The localities explored lie for the most part 

 in South and Middle Holderness, where the trees in the 

 hedgerows and small plantations are chiefly ash, elm, oak, 

 and poplar. Most of them are well known to the members 

 of the Hull Scientific and Field Naturalists' Club, and will 

 no doubt continue to yield an abundant harvest, but it may 



