45 



beiu;^ witli tbe Sordariaceti', as Scbni'tt^r pointed out in liis Kryptoga- 

 inen-Flora von Sclilesiens. The development in the cowpea fnnous of 

 peiithecia with and without beaks on mycebuni derived from a single 

 asc'ospore makes it probable that the same thing oceurs in other genera 

 and tends to «',outirm Winter's view of the untenability of the genus 

 Sphieroderma, wliieh was erected to include those forms of Melanospora 

 destitute of a beak. The development of the perithecia of this fungus, 

 either in the soil near the host or on the surface of the latter (the more 

 common way), or under the substratum in rifts or cavities of the host, 

 shows that this character has no particular value and leads one to sus- 

 pect that the genus Ilyponectria may also have no sound physiological 

 or mor[)hological basis. 



This fungus is most nearly related to the Cosmospora of Raben- 

 horst, which is a good genus and should be reestablished. It differs 

 from Cosmospora chietly in having non-septate ascospores and a 

 wrinkled exospore,the former having Iseptate ascospores with a papil- 

 liite or verrucose exospore. ^ly cultures have shown beyond doubt 

 tliat the ascospore is less readily modified by the substratum than any 

 otlier part of the fungus, and therefore the most important for purposes 

 of classification.^ 



2 These two genera may 1>6 defined brielly as follows: 

 Cusmoftwra Rabh. (emend.). 



Peritbecia as in Nectrla (red in the known species). Asci numerous. Ascospores 

 8 in one row, brown, oblong elliptical, 1-septate, usually more or less constricted 

 at tbe septum, with a distinct papillate or verrucose epispore. Paraphyses 

 present, inconspicuous, broad, loosely jointed, unbranched. Couidial stages 

 unknown. 



1. C. coccinea Rabh. 



2. C. Cameroensis (Rehui). 



Syn. Sphieroderma Cameroensis Rehm. 

 Neocosmospora. 



Perithecia as in Nectria (bright red in the known species). Asci numerous. Asco- 

 spores 8 in one row, brown, globose or short elliptical, continuous, with a dis- 

 tinct wrinkled epispore (the latter sometimes wanting in the smaller spores). 

 Paraphyses present, inconspicuous, broad, loosely Jointed, unbranched, con- 

 sisting of about 5 cells. Three conidial stages, viz, Cephalosporium, Fusa- 

 rium, and Oidium. 



1. N. vasinfecta (Atk.). On cotton (parasitic). 



Perithecia as below. Spores usually globose, wrinkled, generally about 

 10 by 10 //. 

 a. Var. tracheiphila (Smith). On cowpea fparasitic). 



Perithecia quite variable, but mostly 250 to 3.50 /.i tall by 200 to 300 /< 

 broad, with or without a short neck; on the dead roots or in tbe soil 

 over them Spores usually globose, wrinkled, mostly 12 by 12 //. 

 /3. Var. nivea (Smith). On watermelon. Very actively parasitic. Enters 

 the plant from the earth and plugs the vascular system, causing a sud- 

 den extensive wilt of the foliage. 

 Perithecia as above. Spores globose or elliptical, wrinkled or smooth, 

 generally smaller than in the preceding and more often elliptical, but 

 variable. 



