170 



ENDOSPOKEAE 



[ECHENOSTELIUM 



Genus 23.— ECHINOSTELIUM de Bary in Rost. Versuch, 

 7 (1873). Sporangia stalked, very minute, 50 \x diam., 

 colourless ; capillitium branches few, arising from the apex 

 of a short columella.* 



1. E. minutum de Bary I.e. Plasmodium colourless. Spor- 

 angia scattered, stalked, colourless, globose, 40 to 50 /;. diam. 

 Sporangium-wall persistent at the base as a minute collar. 

 Stalk setaceous, narrowed upwards, 0*4 mm. long, hyaline, 

 enclosing nearly colourless refuse matter. Columella slender, 

 3 to 4 jx high. Capillitium of two or three colourless zigzag 

 threads, simple or sparingly branched and anastomosing, 

 with free spine-like branches. Spores colourless, smooth, 

 6 ix diam. — Rost. Mon., p. 215, figs. 53, 54, 58, 68 ; Mass. 

 Mom, 109. 



PI. 128. — /. sporangia (Dumfriesshire) ; g. sporangium showing capillitium ; 

 all the spores but two are dispersed ; h. various forms of capillitium ; i. spores. 



This inconspicuous species appears to be most nearly allied to 



Clastoderma Debaryanum. It may be easily mistaken for the 



fruit of a Mucor, which it superficially resembles. The only British 



gatherings recorded are two made by Miss A. L. Smith who found it 



on dead wood in Dumfriesshire, and also in Herefordshire. The spore 



has not a perfectly uniform wall, but is divided into areolae by thin 



lines of dehiscence. 



Hab. On dead wood. — Hereford (B.M. slide) ; Austria (B.M. slide.) 



Order II. — Amaurochaetaceae. 



Sporangia combined into an aethalium. Capillitium dark 

 purple-brown, of irregular strands and threads, or of complex 

 structure. 



KEY TO THE GENERA OF AMAUROCHAETACEAE. 

 Capillitium of irregularly branching threads. 



(24) Amattrochaete. 



Fig. 32. — Arnaurochaete luliginosa Macbr. 



a. Aethalium. Half natural size. 



b. Capillitium. Magnified 10 times. 



Fig. 32. 



* Eeimerlia hyalina F. v. Hohnel (Ann. Myc. i., 391 (1903) ), which has by 

 some writers been included among the Mycetozoa, does not appear to belong 

 to this group. Very little is known of its life history. The minute colourless 

 sporangia sorrjwhat resemble those of Echinostelium minutum in size and 

 shape. The slender subulate stalk penetrates the sporangium to form a long colu- 

 mella ; there is no capillitium ; the spores are held together by a drop of hyaline 

 mucilage ; they do not give rise to amoeboid bodies, but the contents consist of a long 

 closely coiled thread : when placed in water the spore-wall bursts and the thread 

 rapidly straightens into a non-motile rod 70 to 80 ix long, 0'2 ^ wide. These observa- 

 tions were made on specimens that appeared on dead wood at Lyme Regis in July, 1904 : 

 the further fate of the threads was not traced. It appears possible that Endodromia 

 vitrea Berk. (Hook. Journ. Bot., iii. 78, t. 1, f. c. (1841) ) is the same species. 



