lepldoderma] 



STEMONITACEAE 



141 



PL 116. — a. sporangia approaching var. Chailletti (Arolla, Switzerland) ; b. spor- 

 angia of var. Chailletii (Devonshire) ; c. sporangia with walls broken and showing colu- 

 mellae ; d. capillitium and spores of same with fragment of sporangium-wall and 

 crystalline scales ; e. spore of same. 



The most perfect development of this variable species appears to be 

 represented by two British gatherings of the var. Chailletii, made 

 respectively in Somerset and Devon, in winter time, by Miss Agnes Fry 

 and Mrs. Montague. The sporangia are globose and provided usually 

 with short stalks and well developed columellae. Rostafinski's type 

 of Lepidoderma Chailletii, from Hauenstein, Bohemia, has hemispherical 

 or elongated sporangia, sessile on broad bases, with columellae low 

 and ridge-like or hardly developed ; this variety appears to be a more 

 alpine form, and is abundant on the Jura Mountains and on the Swiss 

 Alps after the winter snows have melted. Every transition may be 

 found between the var. Chailletii with sessile and often confluent 

 sporangia, and the long plasmodiocarps of typical L. Carestianum. 

 All stages also occur on the Alps between plasmodiocarps having 

 normal capillitium free from lime, and those with capillitium branching 

 to form the sponge-like network enclosing abundant lime-nodules 

 characteristic of the var. granuliferum ; the latter variety has now 

 been obtained from California, Sweden and Switzerland. Prof. Farlow 

 finds that the typical form is abundant on the mountains of New 

 Hampshire in the spring-time. 



Hab. On dead leaves, twigs, etc., chiefly in alpine regions. — 

 Devon (B.M. 2521); Sweden (B.M. 2523); Jura (B.M. 2522); North 

 Italy (B.M. 578) ; Chocorua, New Hampshire (B.M. 2524) ; California 

 (B.M. 1362). 



Subcokort II.— AM A UROCHAETINEAE. 



Sporangia single, or combined into an aethalium, without 

 deposits of lime ; capillitium and spores dark brown or 

 violet-brown , rarely ferruginous or colourless. 



Order I. — Stemonitaceae. 

 Sporangia stalked ; sporangium-wall a delicate membrane, 

 often evanescent ; stalk extending within the sporangium 

 as a columella from which the branching threads of the 

 capillitium take their origin. 



KEY TO THE GENERA OF STEMONITACEAE. 



Sporangium-wall evanescent ; capillitium springing from all 

 parts of the elongated columella, ultimate branchlets united 

 to form a superficial net. (18) Stemonitis. 



Fig. 26. — Stemonitis splendens Host. 



a. Group of sporangia. Natural size. 



b. Portion of capillitium and columella. Magnified 



42 times. 



Fig. 26. 



