Dictydi.cthalium.] BRITISH MYCETOZOA. 



33 



ORDER IV.— RETICULARIACEjE. 



Genus 24. DICTYDIiETHALIUM Rostafinski.— iEthalium flat, 

 formed of erect columnar sporangia. Sporangium-wall incomplete, 

 dome-shaped on the top, continued down to the hypothallus in four 

 to six straight threads. 



1. D. plumbeum Rost. — .rEthalium dull slate or clay coloured, 

 minutely areolated with the convex apices of the sporangia. Spores 

 pale yellow, spinulose, 9 to 12 /a diam. 



Hab. On dead wood. 



DlCTYDI-ETHALIUM PLUMBEUM 



Rost. 



a. iEthalium. Natural size. 



b. Eight sporangia of an astha- 



lium isolated ; in three the 

 column of spores has fallen 

 away, leaving the cap and 

 persistent threads. Magni- 

 fied 20 times. ■ 



Fig. 33. 



Knteridium olivaceum 



Ehrenb. 



a. Plasmodiocarp. Magnified 



twice. 



b. Part of spurious capillitium. 



Magnified 35 times. 



c. A spore cluster, and one 



isolated spore. Magnified 

 210 times. 



Genus 25. ENTERIDIUM Ehrenberg. — rEthalium composed 

 of confluent interwoven sporangia, their walls perforated with large 

 openings. 



1. E. olivaceum Ehrenb. — .rEthalium pulvinate, olive-brown; 

 sporangium-walls yellow-olive. Spores in clusters of 6 to 20, some- 

 times free, pale olive, warted on one side, 9 to 12 p. diam. 



Hab. On dead wood. 



Genus 26. RETICULARIA Bulliard. 

 — ^Ethalia composed of interwoven sporan- 

 gia ; the persistent portion of their walls 

 rusty brown, forming broad membranous 

 folds and strands, dividing above into 

 narrow threads. 



1. R. Lycoperdon Bull. — iEthalium 

 pulvinate, 2 to 6 cm. diam., at first en- 

 closed by a silvery cortex. Spores pale 

 rusty-brown, closely reticulate on one side, 

 6 to 8 fa diam. 



Hab. On stumps. Common, 



Reticularia Lycoperdon 

 Bull. 



rt. j^thalium. Natural size. 

 b. Fragment of capillitium. 

 Magnified 100 times. 



