L1STERELLA] MARGAR1TACEAE 261 



with regular and close spiral bands, dividing above into a brush of 

 more slender straight threads ; the spores are pale pinkish-brown, and 

 distinctly warted. Where the development has been checked by cold 

 or dry weather, the threads are pale olive and divide into irregular or 

 lax branches and show indistinct spiral markings ; or the spiral 

 character may be wanting or replaced by broad or narrow rings ; 

 associated with this form the spores are paler, and faintly warted or 

 nearly smooth. In cultivations where the plasmodium has been injured 

 in conveying it indoors, the capillitium often forms very irregularly, 

 the threads anastomosing with broad and flat expansions and showing 

 no appearance of spirals. Gatherings of this form were also obtained 

 by Mr. Camm from Smethwick, Stafford, after cold weather, and are 

 described by Massee as a distinct species Prototrichia chamaeleontina* 

 Little now remains of the type of Trichia metallica Berk, from Tasmania 

 (K. 1741) ; but the specimen is referred to Prototrichia flagellifera by 

 Rostafmski, who saw it in good condition, and by the rule of priority 

 Berkeley's earlier specific name must be retained. The type of Trichia 

 flagellifer Berk, from Badminton (B.M. 333) is the form of the present 

 species with olivaceous capillitium marked with faint spirals, and 

 having nearly smooth spores. The type of P. elegant ula Rost., from 

 Sweden (K. 1743), is a more perfect development with the spirals well 

 marked and with distinctly warted spores. P. cuprea Mass., from 

 Scarborough and Carlisle (K. 1744, 1745), is a similar form with 

 minutely warted spores. The large and varied gatherings from Lyme 

 Regis show that the specimens quoted above represent one species 

 whose diverging forms are too inconstant to be defined even as varieties. 

 P. metallica is said to be not uncommon in the forests of the western 

 States of America. 



Hah. On dead sticks, bark, etc. — Batheaston, Somerset (B.M. 324) ; 

 Badminton, Gloucester (B.M. 333) ; Lyme Regis, Dorset (B.M. 1539) ; 

 Smethwick, Stafford (B.M. 3173) ; Luton, Beds (B.M. 3174) ; Hedon, 

 Yorks (B.M. 3176) ; Benthall, Salop (B.M. 3177) ; Alnwick, Northumber- 

 land (B.M. 3178); Berwick (Phillips Herb.); Aberdeenshire (B.M. 

 3179) ; Letterfrack, Ireland (B.M. 3175) ; Holstein (B.M. 3180) ; Norway 

 (Christiania Herb.) ; Sweden (K. 1743) ; Jura Mountains (B.M. 3181) :. 

 Tasmania (K. 1741) ; Washington State, U.S.A. (B.M. 3182). 



Genus 49. LISTERELLA Jalm in Ber. Deutsch. Bot. 

 Gesellsch., xxiv. 540 (1906). Sporangia minute, hemispherical 

 brownish- black, dehiscing in lobes ; sporangium- wall mem- 

 branous ; capillitium of very slender threads marked with 

 moniliform thickenings, attached to the sporangium-wall ; 

 spores grey. 



1. L. paradoxa Jahn I.e., 538, t. xxii, figs. 1-7. Plas- 

 modium ? Sporangia scattered, sessile, hemispherical or pul- 

 vinate on an expanded base, 0-2 to 0-3 mm. diam., dull 

 blackish-brown, marked with shining ridges corresponding 

 with the lines of dehiscence ; sporangium- wall membranous, 



* It is unfortunate that Cornuvia metallica Rost. ( = Margarita metallica Lister) 

 should have been cited by Mr. Massee as a synonym for Prototrichia chamaeleontina. 



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