166 Mycetozoa of North America 



Sporangia narrowly cylindrical; capillitial threads usually 

 uniting to form a close, uneven surface-net; spores pale violet- 

 gray, faintly warted, 5-7 /x diam. 



Type locality: England. 



Habitat: On dead leaves, rarely on wood; var. gracilis on 

 herbaceous stems. 



Distribution: Universally distributed in North America; 

 varieties not rare. 



Illustration: Lister, Mycetozoa ed. 3. pi. 126, figs, a-e, i-l. 



The typical form with pale, inversely obovoid sporangia is 

 fairly common. Ya.r. fusca usually has more cylindrical sporangia 

 with a darker color. Var. gracilis is very close to C. suhcaespi- 

 tosa, but more narrowly cylindrical, and the stalks are longer, 

 about one third of the total height. The habitat of var. gracilis 

 is usually on herbaceous stalks, thus differing from C. subcaespi- 

 tosa. The slight differences in the color of the spores are some- 

 times not noticeable. The species, as a whole, is related to C. 

 nigra, differing in the paler capillitium of the typical form, and 

 the paler, more strongly marked spores. 



14. Comatricha tenerrima (Curt.) G. Lister, Guide Brit. Mycet. 

 ed. 4. 39. 1919. 



Stemonitis tenerrima Curt. Am. Jour. Sc. II. 6: 352. 1848. 

 Comatricha pulchella (Bab.) Rost. var. tenerrima (Curt.) Lister, Mycetozoa 

 ed. 2. 156. 1911. 



Plasmodium watery white (Lister). Sporangia scattered, 

 stalked, ovoid or narrowly cylindrical, acute or obtuse, pale red, 

 brownish pink, or lilac-pink, equal to or shorter than the slender 

 black stalks; total height 1.5 to 2 mm. Columella slender, often 

 reaching to the summit of the sporangium. Capillitium a net- 

 work of slender, flexuose, pale red threads. Spores pale flesh- 

 colored, minutely warted, 7-8 n diam. 



Type locality: South Carolina. 



Habitat: On herbaceous stalks. 



Distribution: *Antigua, *Pennsylvania, Quebec, *South 

 Carolina. 



Illustration: Lister, Mycetozoa ed. 3. pi. 126, figs. f-h. 



I have made two collections of this species in Quebec, and it is 

 either rare, or often confused with C. pulchella, from which it 

 differs only by the paler color and longer stalks. The emphasis 

 laid on reddish colors in the description, which is copied from 



