332 Transactions of the Society. 



hypb» of the previous experiment, and planted in fresh, tuhes in a 

 similar manner. They grew into mycelium, which fructified 

 exactly as in Experiment 9. 



These experiments have been repeated several times with 

 uniform results. 



Lite-History. 



A. Spores as met with in ringworm hairs are small, round or 

 ovoid bodies, which vary in size from 8 yu, to 7 fi, and are 

 highly ref'ractile in appearance. They are arranged in lines in the 

 substance of the hairs, while on the surface they form a thick 

 coating obscuring the mycelium from which they spring. (Plate 

 VII. fig. la.) 



B. 12 hours cultivation. — After 12 hours the spores become 

 swollen to three or four times their original size. Their contents 

 are more hyaline and le.5s refractile, and at one or more points of 

 the circumference a minute protrusion appears, making the spore 

 pear-shaped. (Fig. Ih.) 



C. 24 hours' cultivation. — In 24 hours the protrusion becomes 

 elongated into a retort-shaped body. In many cases a distinct 

 constriction marks the spot at which the filament arises from the 

 spore. (Fig. 2.) 



D. 48 hours' growth. — In 48 hours some of the filaments had 

 reached a length of • 7 to 0*9 mm., becoming more or less 

 tortuous. (Fig. 3.) 



E. Third day. — During the third day growth of filaments and 

 twisting continues. 



F. Fourth and fifth days. — During the fourth and fifth days 

 the filaments increase in length and branching takes place. No 

 other change. 



G-. Sixth, seventh, and eighth days. — By continued branching 

 of filaments a dense network is formed, and in preparations in 

 which entire hairs were placed it was impossible to trace an 

 individual filament from spore to termination. (Fig. 4.) 



This, however, we have done in specimens in which isolated 

 spores have been sown. At this stage, in portions of the mycelium, 

 the protoplasm shows in its centre brightly refractile spots 

 varying in size, and septa are seen immediately above the point 

 of branching. (Fig. 5.) 



H. — The end of some of the filaments show bulbous and pear- 

 shaped enlargements, but these do not in any case go on to spore 

 formation. 



I. Aerial hyphse and fructification. — As soon as the filaments 

 reached the margin of the jelly and were exposed to air they 

 divided into two or three short branches, on the extremities of 

 which a basidium and sterigmata were developed. (Fig. 6.) 



