150 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
encroaching on the basidiosporic fructification. He makes no mention 
of them in describing his cultures of other species. The writer finds 
chlamydospores to be of much wider distribution than Brefeld had 
supposed, particularly upon the vegetative mycelium. Further cul¬ 
ture study will assuredly add many names to this list and show the 
wide distribution of chlamydospores among all families of Hymeno- 
mycetes. They are undoubtedly important reproductive organs of 
the vegetative mycelium in many species. 
The formation of the chlamydospore agrees with the process known 
in other groups of fungi, as in Mucor racemosus, but the development 
will be outlined here for purposes of comparison with the spores of 
Michenera artocreas (see p. 155). The method of development does 
not vary in the species examined, and is well illustrated in Corticium 
efjuscatum and Lentodium squamiilosum (pi. 21, fig. 80-83, and pi. 
22, fig. 110-114). Any cell of the mycelium may form a chlamydo¬ 
spore, hence the position is either terminal or intercalary; and in 
species which produce them profusely they are thickly strewn along 
the hyphae, and the intervening spaces are spanned by the empty 
hypha walls (pi. 21, fig. 80). In the process of formation the proto¬ 
plasm of the hypha becomes vacuolate, certain cells losing their con¬ 
tents entirely, while in others which are to produce chlamydospores 
the condensing protoplasm draws away from the ends of the cell and 
concentrates in the middle region where the side walls bulge to receive 
it (pi. 21, fig. 82). Here a resistant wall (endospore) forms about the 
encysting cell within and adnate to the hypha walls on each side, and 
cuts off the empty portion of the parent cell at each end. f on- 
tinued contraction of the protoplasm may cause the abandonment 
of these end walls, and the formation of new walls farther in (pi. 21, 
fig. 83; pi. 22, fig. 111). The mature chlamydospore is thick-walled, 
with dense, granular, refractive contents becoming vacuolate with age. 
The usual form is lemon-shaped, but great variation is shown on 
account of different degrees of contraction of the protoplasm. Hence 
in the same culture we may find all shapes from spheres to cylindrical 
cells whose walls have become resistant; the latter function in every 
way as normal chlamydospores (pi. 22, fig. 112-114). The mature 
spores are freed only by the decay of the empty portion of the parent 
hypha, and are able to withstand adverse conditions for a considerable 
period. In drop cultures they germinate at once by the formation 
of from one to several germ tubes (pi. 21, fig. 84-85; pi. 22, fig. 115). 
