424: Agricultural Experiment Station, Ithaca, N. Y. 



enongli of tliem retaining their original form to prove that thej 

 were really from the original aseus of the Cordyceps. 



Germination from these swollen spore-segments takes place by the 

 production of germ-tubes at one or two points. These soon become 

 branched. The protoplasm is at first hyaline and homogeneous. 

 After three days large vacuoles appear irregularly placed. The 

 threads are strongly segmented and the branches are strongly con- 

 stricted at the base. In some cases a healthy thread becomes sud- 

 denly constricted and produces an aborted apex of less than half the 

 diameter of the ordinary thread (Fig. 45). The aborted portion is 

 usually curled. In some cases the entire growth presents a much 

 swollen appearance, being about twice the diameter of the ordinary 

 threads. The segments of these swollen colonies always contain 

 large vacuoles (Fig. 4G). In about four days the growth appears 

 above the surface of the agar. A strong, white cottony growth 

 appears forming a colony circular in form. At the end of about six 

 days the conidia appear. Short sterigmata are borne near the ends 

 of the long, cottony threads. They are irregularly arranged either 

 in an opposite or an alternate manner. They are flask-shaped and 

 slender and sometimes forked. The conidia are nearly spherical 

 and are borne in short chains of three or four at the ends oi the 

 sterigmata, or at the end of a long thread. The chains are seldom 

 seen for they almost invariably collapse leaving the conidia in balls 

 at the ends of the sterigmata. This is probably due to a thin film 

 of moisture clinging to the surface. 



The growth on potato becomes visible after about six days. The 

 light yellow or white mycelium spreads loosely over the surface of 

 the potato. After about a month the surface becomes densely 

 felted, and in another month it becomes buff in color. The mycelium 

 on the surface of the potato and the potato itself are colored pale 

 orange or brilliant chrome yellow wherever they touch the glass. 

 ]^o Isaria-sporophores have been observed. A culture was made in 

 a half-litre flask of potato, and quite a marked diiference in the habit 

 of growth was seen between this and the smaller tubes. The flask 

 culture showed the beginning of a sporophore, deep reddish-orange 

 in color, at the end of about three months. This is probably the 

 beginning of an ascophore, since it appeared after the conidial 

 growth had ceased, and at the same time that rudimentary perithe- 

 cia were produced. The color also agrees with the color of the 

 original specimen, which is in the perfect stage. At the end of two 



