LICE ACE JE. 



149 



Dictydium umbilicatum, with two to four minute purple granules on 

 the spore wall ; the stalks are stout and rugged, but of the same 

 purple-brown colour as in the latter species. The type of Cribraria 

 exilis Macbride, from Nicaragua (B. M. 1026), is an almost typical 

 form of Dictydium umbilicatum, with a shallow cup connecting the 

 slender parallel ribs at the base. 



Hob. On dead wood. - -Lyme Regis, Dorset (L:B.M.119) ; Wan- 

 stead, Essex (L:B.M.119) ; Luton, Beds (L:B.M.119) ; Glamis, 

 Scotland (B. M. 241) ; France (Paris Herb.) : Germany (B. M. 660, 

 663) ; Italy (B. M. 659) ; Ceylon (B. M. 670) ; Borneo (L:B.M.119) ; 

 Maine (B. M. 1105) ; Philadelphia (L:B.M. 119) ; Iowa (B. M. 821) ; 

 S. Carolina (B. M. 666) ; Nicaragua (B. M. 1026). 



SPECIES NOT MET WITH IN THE QUOTED COLLECTIONS. 



2. D. venosum Schrad., Nov. Gen. Plant., p. 14, pi. iii., fig. 6 

 (1797). Scarcely a line high; sporangia spherical, cernuous, 

 more or less as in D. umbilicatum, yellowish-brown, when the 

 spores are shed, colourless ; veined with nine to twelve ribs of 

 rather a brighter colour, the final branches of the ribs lateral, 

 usually not anastomosing; stalk slender, flexuose, brownish. 



Hob. On rotten pine wood. 



Possibly a form of D. umbilicatum, with an irregular net. 



Order II. LICEACE.E. Sporangia solitary, sessile or stalked; 

 sporangium-wall cartilaginous; capillitium and colurnella wanting. 



KEY TO THE GENEPvA OF LICE AGE M 



Sporangia sessile, globose or plasmodiocarps. (25) LICEA. 



Fig. 33. Lieea Jlt'.mosa Fers. 



a. liroup of plasmodiocarps. Twice natural size. 



b. riasmoJiucarp. Magnified <> times. 



c. Spores. Magnified 200 times. 



Fig. So. 



Sporangia stalked, furnished with a lid of thinner substance. 



(26) ORCADELLA. 



Fig. 34. Orcadella operculata Wingate. 



a. Group of sporangia. Magnified 8 times. 



b. Sporangium with open lid. Magnified 80 



times. 



a 



Fig 34. 



