Fimbriate Mouths (Fig. 6). A few species (mostly South American) have 

 mouths appearing fibrillose, which is the texture of the peridium walls form- 

 ing the mouth. This is a different structure from the preceding type in which 

 the fibrillose layer surrounding the mouth is adnate to the peridium. These 

 mouths we would call fimbriate, and although the term is inaccurate, it is the 

 term applied to Geasters with such mouths. There is a tradition in Europe that 

 there is a fimbriate mouthed species in Europe, and such a species (Tylostoma 

 fimbriatum) is usually carried in their books. I am satisfied no such species 

 occurs in Europe and that it is purely an error.f 



COLOR. In practice I find that the color of the peridium is an important 

 character to distinguish species, and most specimens can be readily distinguished 

 as "colored" or "uncolored." The term "uncolored," of course, does not mean 

 white, but pale and not marked witli shades of reddish brown as the "colored" 

 species have. Rarely we note specimens the same in all other characters but 

 varying as colored and uncolored. In such cases we consider color subordinate, 

 but usually color is a constant and strong character. Stems also vary in degrees 

 of color but not as markedly as the peridium. 



CAPILLITIUM. The capillitium of Tylostoma is always composed of 

 branched, hollow, septate, tubular threads. Usually it is subhyaline under the 

 microscope or slightly colored. I think the color varies according to the condi- 

 tions, age, etc., of the specimens. The color is rarely enough developed to form 

 a marked character in but three species to my knowledge, viz. : volvulatum.J 

 obesum and the allied Schizostoma laceratum. Recently elaborate articles have 

 been written on the septation of Tylostoma capillitium and it is claimed that 

 constant characters for each species can be drawn from such septation. I do not 

 deny that septation varies, sometimes rounded at the ends, sometimes squarely 

 joined, sometimes swollen, sometimes not. but I have frequently noted more 

 than one character on the same slide and I have not found it of service, in 

 practice, to distinguish species. I have noted the septation characters as I see 

 them in my descriptions but I do not place much stress on them. 



SPORES. The spores of Tylostomas are generally very uniform in size, 

 usually 5-6 mic. Tylostoma Longii has very small spores, 2^-3 mic., but as it 

 agrees with albicans in all other characters I hold it to be a variety. The surface 

 of spores affords better characters. Some species have smooth spores, most have 

 granular spores and a few have aculeate spores. Smooth spores when dry often 

 appear rough because of the shrivelling of the surface. It is therefore well to 

 treat spores with warm lactic acid to swell the epispore in order to be sure of 

 their character. Even then it is sometimes difficult to decide if the spore is 

 smooth or slightly granular. In all such cases we have noted the spores as 

 smooth. 



STEMS. Internally the stems of Tylostomas are very similar, usually hol- 

 low, with some loose, central fibrils. Externally the bark or cortex often affords 

 good characters. Frequently it is smooth or longitudinally striate ; often it is 

 broken into little scales ; sometimes it develops or is torn into large, generally 

 caducous, scales. Species having these scales are strongly marked when grow- 

 ing but can not always be recognized from the herbarium specimens as the 

 scales generally fall away. A few species of Tylostoma have a distinct sheath 

 surrounding the stem. In one species (volvulatum) the sheath breaks, part 

 forming a collar at the base of the peridium, part a cup at the base of the stem. 

 In this case it is known (not correctly I think) as a volva. To my knowledge 

 two other species have distinct sheaths hut of a more fibrillose nature, breaking 

 irregularly and forming a torn collar. In reality all species of Tylostoma have 

 stem "sheaths," but in most species it is closely adnate to the stem and forms 

 the cortex or "bark" of the stem. 



t Dr. Hollos in his recent work shows an enlarged drawing of the mouth of 

 Tylostoma fimbriatum." I think the Doctor either imagined a mouth to fit the 

 name, or got his ideas from some of the misnamed specimens from South America 

 to be found in the museum of Berlin. I have never seen a specimen from Europe 

 with such a mouth and I do not believe it occurs. 



t To show how observers often differ on such subjects it may be cited that 

 Fetri describes the capillitium of volvulatum as hyaline. 



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