156 ENDOSPOEE^. [ALWISI 



of numerous irregular, tubular threads, 0'5 to 1 mm. long, 3 

 18 /t wide at their origin at the apex of the sporangium, when 

 they radiate downwards, tapering and branching at a wide ang 

 below, the slender extremities attached to the wall about ha] 

 way down the sporangium ; pale red, beset with minute scatter! 

 papillse. Spores pale red, closely reticulated over the great 

 part of the surface, the remaining part loosely reticulated, 5 to 

 fx. diam. — Mass., in Journ. R. Micr. Soc. (1889), p. 349. Trich 

 fragilis Eost., Mon., App., p. 39 (in part). Prototrichia Bomhan 

 Mass., Mon., p. 128. 



Plate LVIII., B. — a. clusters of sporangia, x 2 ; J. cluster of sporang: 

 X 20 ; e. immature sporangia, from a mounting in glycerine, showin 

 through the walls, the capillitium threads arising from the apex of t 

 sporangium, x 20 ; d. fragment , of upper sporangium- wall, from whi 

 three capillitium threads proceed, only a small part of the thread show 

 X 280 ; e. fragment of sporangium-wall to which the lower end of a branchii 

 capillitium thread is attached, x 280 ;/. spores, x 600 (Ceylon). 



This species is represented by a single gathering in July 1868 1 

 Thwaites from Ceylon. The sporangia are to a large extent immatui 

 purplish, and with the spores imperfectly developed, but a few a 

 nearly mature and show the rufous-brown colour described abov 

 Although the character of the long clustered stalks is peculiar, tl 

 colour and texture of the sporangium-wall, and the colour, size, ai 

 markings of the spores are similar to what is ^en in other membe 

 of the TubulinecB, while the threads of the capillitium find a clo 

 analogy in the tubular extensions of the sporangium-wall of Siph 

 ptycMum. 



Hah. On Jungermannia, growing on decayed wood. — GrongoUa Forei 

 Oeylon (B. M. 1000). 



Order IV. — E.ETicuLAEiACEiB. Sporangia combined into i 

 sethalium ; sporangium-walls incomplete, perforated, or forming 

 spurious capilHtium. 



KEY TO THE GENERA OF RETIGULARIACE^. 



Sporangium-wall cap-shaped at the apex, continued down to t 

 hypothallus in four to six straight threads. 



(30) DlCTYDI^THALlU 



Fig. 38. — Dietydusthalium plmnbeum, Eost 



a. .3Sthalium. Natural size. 



i. Eight sporangia of an sethalium isolated ; in 

 three the column of spores has fallen away, 

 leaving the cap and persistent threads. Mag- 

 nified 20 times. 



