STRUCTURE. 31 



joints, from which, especially from the last, spring short branch- 

 lets, often consisting of a single cell. Sometimes two or more 

 branchlets spring from the same point. Occasionally the threads 

 are constricted without any dissepiments, the terminal articula- 

 tions are obtuse, and soon swell very much, so as greatly to 

 exceed in diameter those on which they are seated. When arrived 

 at their full growth, they are somewhat obovate, and produce 

 four spicules, which at length are surmounted each with a glo- 

 bose spore. When the spores are fully developed, the sporophores 

 wither, and if a solution of iodine be applied, which changes 

 the spores to a rich brown, they will be seen still adhering by 

 their spicules to the faded sporophores. The spores soon 

 become free, but the spicule often still adheres to them ; 

 but they are not attached to the intermingled filaments. 

 In Bovista plumbed, the spores have very long peduncles.* As 

 in the Hyrnenowiycetes, the prevailing type of reproductive organs 

 consisted of quaternary spores borne on spicules ; so in Gastero- 

 mycetes, the prevailing type, in so far as it is yet known, is very 

 similar, in some cases nearly identical, consisting of a definite 

 number of minute spores borne on spicules seated on basidia. 

 In a very large number of genera, the minute structure and 

 development of the fructification (beyond the mature spores) 

 is almost unknown, but from analogy it may be concluded that 

 a method prevails in a large group like the Myxogastrcs which 

 does not differ in essential particulars from that which is known 

 to exist in other groups. The difficulties in the way of studying 

 the development of the spores in this are far greater than in the 

 previous order. 



MyxogastrSs. — At one time that celebrated mycologist, Pro- 

 cessor De Bary, seemed disposed to exclude this group from the 

 vegetable kingdom altogether, and relegate them to a companion- 

 ship with amoeboid forms. But in more recent works he seems 

 to have reconsidered, and almost, if not entirely, abandoned, 

 that disposition. These fungij mostly minute, are characterized 

 in their early stages by their gelatinous nature. The substance 



* Berkeley, "On the Fructification of Lycoperdon, &c," in "Annals of 

 Natural History" (1840), iv. p. 155. 



