TRICHIA.] TRICHIACEjE. 169 



Hist. Iowa, ii., p. 132 ; Mass., Mon., p. 180. Trichia reniformis 

 Peck, in Rep. N. York Mus., xxvi., p. 76 ; Mass., Mon., p. 184. 

 Trichia Andersonii Rex, in Proc. Acad. Nat. Sc. Phil. (1891), 

 p. 395. Trichia advenula Mass., in Journ. R. Micr. Soc. (1889), 

 p. 336 ; Mass., Mon., p. 181. T. heterotrichia Balf., in Grev., x., 

 p. 117; Mass., Mon., p. 174. T. loivensis Macbride, I.e., p. 133. 



a. genuina : elaters more or less uneven from constrictions and 

 irregular swellings, with indistinct or rugged spiral thickenings. 



/3. inconspicua : elaters evenly cylindrical, usually swollen 

 behind the gradually tapering pointed ends ; spiral bands distinct, 

 regular, delicate. 



y. lutescens : sporangia yellow, subglobose ; sporangium-wall 

 membranous ; elaters smooth with faint spirals. 



Plate LXL. B. a. a, gcnmna, sporangia, x 20 ; b. sporangium-wall 

 and spores, x 280; <?. elaters. x 600; d. spore, x 600 (England); e. /3. 

 inconspicua, sporangia, x 20 ; /. elater, x 600 (Switzerland : one of Kosta- 

 finski's types). 



Although the two varieties are well contrasted, intermediate forms 

 are of frequent occurrence, and the variations of capillitium described 

 above have on several occasions been found represented in different 

 sporangia of the same group. T. inconsjricua cannot therefore be re- 

 garded as a distinct species. T. reniformis Peck, of which a typical 

 specimen has been received from Dr. Rex, has the granular thickening 

 of the sporangium- wall and the rugged irregular spirals of T. contorta 

 var. genuina. A type specimen of T. Andersonii Rex is very similar to 

 the last in the form of the capillitium, but the brown granules in the 

 sporangium-wall are less abundant. Associated with all varieties of 

 capillitium, the wall in English gatherings may either be densely 

 charged with brown granules resembling the structure in Perichcena 

 corticalis, or it may be similar to that in T. Andersonii ; the difference 

 in colour between spores and capillitium mentioned by Dr. Rex in his 

 description of this species (I.e.} is also a varying character, and it is 

 difficult to separate the form from T. contorla. The type of T. advenula 

 Mass., from Glamis (K. 1748), has the sporangium-wall charged with 

 brown granular matter ; the spirals on the elaters are regular and 

 distinct ; it is similar to Rostafinski's type of T. inconspicua in Strassb. 

 Herb. T. heterotrichia Balf., from Currey's collection (K. 1066), appears 

 to be an immature specimen of T. contorta var. genuina ; the sporangium- 

 walls are almost free from granular deposits ; the elaters are 4 to 5 /A 

 diam., marked with one or three rugged or indistinct spiral bands, and 

 scattered blunt spines ; the spores adhere to one another, and are very 

 faintly minutely spinulose ; they measure 12 to 13 p.. T. lowensis 

 Macbride (I.e.) agrees with T. contorta in the habit and colour of the 

 sporangia, in the granular sporangium-wall, and in the spores ; the 

 elaters are 3 p diam., and, in addition to being marked with about four 

 inconspicuous spiral bands, are beset with numerous slender flexuose 

 spines 5 to 10 /u, long. It appears only to have been found near Iowa 

 City, and exclusively on the bark of poplar in the month of October. 

 Scattered spines are occasionally met with on the elaters of T. contorta, 

 and T. lowensis appears to be an extreme local form of this species ; 

 a type specimen is in the British Museum Herb. Var. y has been 

 found in Norway, September 1894, in considerable abundance, and at 

 stations separated by many miles. The only characters in which it 



