June, 1907] Mycological Bulletin No. 78 329 



several times, the results diminishing with each repetition until they 

 finally ceased to respond. I now noticed that the spore surface that had 

 been most active in exploding the spores had become quite moist. 



After they had rested for some minutes I repeated the experiment 

 with the same result but not so strong as at first. I then put them in 

 a closed box and did not open it until I was inside a warm room. When 

 I removed the lid a dense cloud of spores arose to meet my gaze. I again 

 tried blowing on them and found them very active until exhausted. They 

 varv in color from tan to a rich brown. 



A LITTLE CORTICICOLOUS FUNGUS. 

 Edith Hyde. 



At the request of the editor of the Mycological Bulletin I have studied 

 ar.d figured an interesting little fungus that grows on bark as indicated 

 in the title. The specimens were collected in Jamaica by A. E. Wight and 

 our material was received from Dr. Farlow, of Harvard University. 



The botanical name of the plant is Sphacrostilhe ciunabariiia ; it belongs 

 to the large group called the Ascomycetcs. In this group the fruit or 

 spore-bearing portion may be open and somewhat cup-shaped or saucer- 

 shaped ; or it may be nearly or quite closed and more or less globular 

 or pear-shaped. In the fir.«t case the name Disco)iiycctcs is applied to the 

 plants; in the second case they are called Pyrciiomycctcs. It is to the 

 latter group thrt the Sphaerostilbe belongs. 



The dry specimens examined were of a dark reddish-brown color, the 

 lower portion of tl e stem being much darker thru the upper portion. 

 The tiny plants are clustered on the bark not densely, but as trees in an 

 open woods, as .shown in Figure 2 at a. It will be seen that the upright 

 stem is not the entire plant; the lower portion is made up of a number 

 of globular or slightly pear-shaped bodies clustered about the base of the 

 upright stems (see fig. b). These are the pcrithccia. a greek word which 

 means pockets; these pockets or perithecia, contain spores as will be 

 explained nresently. 



.An inspection of the figures already referred to. will show that the 

 upright portion or stem is decidedly enlarged at the upper end and here 

 also spores are borne. 



There are two kinds of .spores borne by this Sphaerostilbe. very differ- 

 ert e'-ch from the other, but both microscopic. Covering the upper end 

 or head of the upright stem are myriads of little threads which are 

 directed outw,-'rds and on the tip of each is borne a small body called 

 a conidium. Each one is oval or very slightlv egg-shap-^d. The threads, 

 which are really tiny tubes, are called couidiophorcs : the word means 

 hearers of the coi idia. 



The drawing marked c in the figure shows two conidia verv much en- 

 larged. The one at d is a diagram and shows the real structure of the 

 conidiophore, or rather the stem or stipe which bears the multitude of 

 conidiophores. As can be seen, there are innumerable threads or 

 tiniest tubes joined side by side and compacted into a rather firm stem 

 or stipe. These spread out and seem to be multiplied to form the head; 

 the outer frinp^e of hairs produce the spores as has been explained. 



The other kind of spores is to be sought for in the perithecia or 

 globular pockets forming the base of the plant and flanking the upright 

 stem. I'nfortunately they were sterile in the siiecimens examined. But 

 a copy of such .spores was taken from Pflauzoifamilicn, a large illustrated 



