154 ENDOSPOKL'^. [TUBULINA. 



passing across the sporangium or taking an oblique course ; this 

 appearance indicates a tendency in the direction of the marked 

 development of tubular processes in Stplw})tycliium. The substance 

 of the sporangium- wall varies in different gatherings ; it may be 

 delicately membranous, or firm and of considerable thickness. There 

 is also some variation in the shape of the upper portion of the 

 sporangium ; in some American specimens of the more fragile type 

 the apex is produced into a sharp cone ; in others the sporangia are 

 cylindrical, obtuse, and but slightly connected with each other, those 

 on the outside of the cluster being often entirely free ; in the stouter 

 type the walls are closely compacted, their apices forming a level 

 tesselated surface. 



A full account of the forms of Tubulma and their relation to 

 Siphoptyehium is given by Dr. Rex, I.e. T. speclosa Speg. (Nov. Add. 

 ad Myc. Ven., No. 123), from N. Italy, appears from the description 

 to be T. fragiforiiiis, but no mention is made of the size of the spores. 



Nab. On dead wood. Bowood, Wilts (B. M. 302) ; Penzance, 

 Cornwall (B. M. 303) : Luton, Beds (L:B.M.124) ; Clifton, Notting- 

 hamshire (B. M. 1103) ; Wales (B. M. 9, 10); France (Paris Herb.); 

 Germany (B. M. G56) ; Poland (Strassb. Herb.) ; Finland (B. M. 655); 

 India (K. 1650) ; Java (B. M. 1104) ; Japan (K. 1649) ; Java (B. M. 

 1104) ; Australia (K. 1653) ; Philadelphia (L:B.M.124J; Iowa (B. M. 

 823) ; S. Carolina (K. 806). 



2. T. stipitata Host., Mon., p. 223 (1875). Plasmodium white 

 or colourless (teste Rex). Sporangia in shape, size, and colour 

 as in T. fragiformiSj usually clustered on a dark brown spongy 

 hypothallus, which lias the form of a stout common stalk 2 to 

 3 mm. high. Spores pale rufous-brown, minutely reticulated 

 over the greater part of the surface, the remaining part smooth 

 or marked with ridges, 3 to 5 /x diam. Cooke, Myx. Brit., fig. 2 ; 

 Rex, in Bot. Gaz., xv., p. 318 ; Mass., Mon., p. 38. Licea stipitata 

 Berk. & Rav., in Journ. Linn. Soc., x., p. 350 (1868). 



Plate LVII1. , A. d. cluster of sporangia on a stalk-like base, x 3 ; e. 

 spores ; one shows the side on which the reticulation is imperfect, x 600 

 (United States). 



Dr. Rex considers T. stipitata a distinct species from T.fragiformis, 

 specially marked by the smaller spores. The stalk is a less important 

 character, for he states that sessile clusters are not uncommon. The 

 conical form supplied by him and referred to under T. frag if or mis has 

 spores measuring 4 to 6 p, and may represent an intermediate form. 



Hob. On dead wood. Bonin Islands (K. 821); Philadelphia (L:B.M. 

 125) ; S. Carolina (B. M. 538, 929, 946) ; Cuba (B. M. 539). 



SPECIES EXCLUDED FROM THE GENUS. 



T. ccespitosa Mass. = Lindbladia Tubulind Fr. 



T. ejfusa Mass. = Lindbladia Tubulina Fr. 



T.flexuosa Mass. = Licea flexuosa Pers. 



T. minima Mass. = Licea minima Fr. 



T. spermoides Mass. = Lindbladia Tubulina Fr. 



