CHONDROMYCES THAXTERI, A NEW MYXO- 
BACTERIUM 
ic BUF AULL 
(WITH PLATES V AND VI) 
The Myxobacteriaceae constitute an extremely interesting 
assemblage of forms, because of their apparent relationship to the 
bacteria on the one hand, and to the slime molds, particularly 
the Acrasieae, on the other hand. The individual plants are 
bacteria-like rods in all cases, and after a vegetative period these 
swarm together to organize a definitely shaped pseudo-fructification, 
without, except in the one genus Myxococcus, undergoing any 
marked morphological changes themselves. These fructifications 
are not comparable to the more or less heaped up colonies charac- 
teristic of certain bacteria, but, as THAXTER (9) has pointed out, are 
strictly comparable to the “fructifications” of the Acrasieae, the 
only other group in which there exists “‘a similar concerted action 
of aggregates of individuals toward a definite end, namely, the pro- 
duction of a more or less highly differentiated resting state.’’ 
Whether they are to be regarded as a family of bacteria or as a 
division of the Myxomycetes, close to, if not included within the 
Acrasieae, remains undecided. Baur (1) and Quent (4) and more 
- recently Prvoy (3) incline strongly to the former view; VAHLE (10) 
and others incline to the latter view. 
Of the fewer than 30 known bona fide species, distributed 
among 3 genera, 11 have been referred to the complex and variable 
genus Chondromyces. ‘The one described in this paper adds another, 
Chondromyces Thaxteri, n. sp., in some respects the most remark- 
able of all. This form appeared in small quantity on deer dung 
from Algonquin Park Forest Reserve, Ontario, and was successfully 
cultured for more than two years, or until the identity of the species 
was established, when it was allowed to die out. 
The fructifications, or more properly pseudo-fructifications, are 
ordinarily yellowish, but may vary from flesh-colored to reddish 
Botanical Gazette, vol. 62] [226 
