212 THAXTER. 



hut owing to the early activity of the former, from the upper portion 

 of which new cells are rapidly separated, the relation of the two is 

 changed, and the primary subbasal cell becomes the terminal cell of 

 a series which is thus intercalated between the two, and usually forms 

 the fertile portion of a variabl.y de^■eloped axis. This simple condi- 

 tion may be complicated by further secondary cell-activities in special 

 cases, but the fundamental cell-relations are the same in all. 



In Dimorphomyces, on the other hand, although essentially the same 

 process of development takes place and the series of intercalated cells, 

 which has been called the secondary receptacle and from which the 

 perithecia and secondary appendages arise, is produced in a similar 

 fashion, the primary subbasal cell, with its primary appendage, 

 retain their original relations to the basal cell. The apparent diflfer- 

 ence between the two is due to the fact that an outgrowth from the 

 basal cell pushes up beside the subbasal cell, and cutting off a variable 

 number of successive cells from its tip, gives rise to the so-called 

 secondary axis. Although the base of this axis appears to have been 

 derived from the subbasal cell, it is necessarily associated throughout 

 its length with the progressive protrusion of the basal cell which forms a 

 continuous margin, the lumen of which extends from its apex to the 

 foot; although in older indi\'iduals it may be somewhat obliterated 

 by secondary thickening of the wall. The secondary fertile axis is 

 thus also a secondary development intercalated between. the primary 

 basal and subbasal cells, and although the latter remains in contact 

 with the former, it represents the terminal cell of the axis in Dimcro- 

 mijccs, the subbasal cell of which would correspond to the distal cell 

 of the secondary axis in Dimorphomyces. In certain species of the 

 genus a further complication arises from the production of a second 

 fertile axis, similar to the first in structure and development, and often 

 symmetrical in form and position, on the opposite side; but which 

 originates from the primary subbasal cell, an extension of the latter 

 forming a continuous margin on its under side exactly like that of the 

 first, but differing from the fact that its lumen is continuous with that 

 of the subbasal cell. In certain aberrant species of Dimcromyccs, like 

 D. Nccrotalis herewith described, a somewhat similar condition is 

 present; the fertile axis being more or less horizontal, and two or 

 three of its lower cells being margined by a slight extension of the 

 basal cell. As in all other species of the genus, however, the primary 

 subbasal cell has become the terminal cell, far removed from contact 

 with the basal and bearing the primary appendage. On the other 

 hand certain species of Dimorphomyces like D. Pachytclis and certain 



