J. SAUNDERS — NOTES ON THE MYCETOZOA. 141 



rows or scattered heads like tiny pink beads, but these quickly 

 clumsic to a clayey or ochreous hue. The last mentioned species 

 was tirst noticed by tlie writer on a small island in a secluded park, 

 where many trees had fallen and had been allowed to lie un- 

 molested. These formed a perfect cliaos of broken branches and 

 prostrated trunks, over which the still-living trees cast a dense 

 shade, tlie whole being surrounded by a damp atmosphere which 

 just suited the needs of these moisture-loving creatures. 



It should be mentioned that if specimens are collected in an 

 immature state, it is desirable to keep them under an inverted wet 

 glass for a few days, so that the contents of the sporangia may 

 become fully matured, as unless these are so, it would be difficult 

 or impossible to determine the species to which they belong. Many 

 disappointments have been experienced by collectors from not 

 taking these precautions. 



The mature sporangia, or peridia of some authors, have usually 

 well-marked and permanent colours. A whole series of them, 

 including about one third of the known British genera, have opaque 

 white heads, the whiteness being due to the presence of lime, which 

 is deposited on the surface during the process of ripening. This 

 group is hence called the Calcareae. Most of these contain violet 

 or dark broAvn spores, and it is desirable always to examine the 

 colour of the spores, as this is an important point in classification. 

 This is easily done, either by rubbing a sporangium between the 

 fingers, or better still, upon a piece of white paper. It will be 

 seen that not only those with lime-covered heads, but also many 

 other species, have violet or brownish-violet spores. The genera 

 with these characters comprise about one half of those found in 

 this country. 



It is desirable to see that the specimens collected really contain 

 spores, so that one may be spared the experience of the writer, 

 who on one occasion found what at first sight appeared to be an 

 interesting group of heads, with the resemblance of an operculum 

 to each. On a careful microscopic examination of the contents of 

 the supposed sporangia, no spores could be detected, but instead, 

 only a watery fluid. Upon a re-examination of the general appear- 

 ance of the specimen it resolved itself into a group of eggs of one 

 of the Lepidoptera ! As some consolation for the disappointment, 

 one felt that true knowledge is obtained not only by the observation 

 of facts, but also by the rectification of error. Our national collec- 

 tions also are not absolutely free from similar inaccuracies. 



Amongst the genera with dark-coloured spores is a small group 

 which are like the reed-mace {Typha^ in miniature. These may 

 either be grouped, like a tiny forest, with separate stems and closely- 

 compacted heads {Stemonitis), each head composed of an intricate 

 network of most delicate threads ; or both stems and sporangia may 

 stand singly ( Comatrichia). 



A very abundant and generally-distributed genus [Trichia) has 

 bright yellow spores and capillitium. This network or capillitium 

 was called "wool" by some of the descriptive botanists of last 



