COMATRICHA 159 



but they are not constant in different collections. C. Ellisii is 

 merely one of the numerous phases grouped together under C. laxa 

 as a center. 



4. Comatricha rubens Lister, Mycetozoa 123. 1894. (N. Y. 

 B. G. nos. 487, 752, 11376, authentic material.) 



Plasmodium watery white (Lister). Total height 1 to 2 mm. 

 Sporangia obovoid, ellipsoid, or subglobose, scattered, stalked, 

 erect or inclined, 0.5 to 0.8 mm. long, 0.3 to 0.5 mm. broad, pink- 

 ish brown, shining below; sporangial wall evanescent above, mem- 

 branous and persistent in the lower quarter, pinkish brown. 

 Stalk setaceous, black, shining, 0.6 to 1.3 mm. long, rising from a 

 circular, brown hypothallus. Columella reaching to about two 

 thirds the height of the sporangium, branching at the apex. 

 Capillitium of purplish brown threads, springing from all parts 

 of the columella, broad at the base, more or less fiexuose, anas- 

 tomosing and branching at wide angles, often with flat expansions, 

 gradually narrowing to the slender, straight, free ends; the per- 

 sistent base of the sporangial wall connected with the lower part 

 of the columella by capillitial threads with broad attachments. 

 Spores pale lilac-brown, minutely spinulose, 7-8 fx diam. 



Type locality: England. 



Habitat: On dead leaves. 



Distribution: *Colorado, Maine, Massachusetts, New York, 

 *Oregon, Pennsylvania, Quebec, Virginia. 



Illustration: Lister, Mycetozoa ed. 3. pi. 127, figs. d-f. 



American collections agree perfectly with the above descrip- 

 tion of the English ones by Lister, except that as a rule the 

 sporangia are a little smaller. The species forms small colonies, 

 and is not rare in regions where intensive search is made. Its 

 appearance in the field differs from C. pulchella and C. tenerrima, 

 also pale forms, by the sporangial shape. The persistent base of 

 the sporangial wall with its capillitial attachments is a constant 

 feature. 



5. Comatricha lurida Lister, Mycetozoa 119. 1894. (N. Y. 

 B. G. nos. 11865, 11866, authentic material.) 



Plasmodium watery white (Lister). Total height 1.25 mm. 

 Sporangia globose or short-ovoid, erect, 0.5 mm. diam., scattered, 

 stalked, purplish brown; sporangial wall evanescent. Stalk 



