New British Discomycetes. W. D. Buckley. 47 



This species is distinguished from its aUies by the extreme 

 fineness of the reticulations on the spores. A comparatively 

 large species it is easily seen on account of its brilliant colour. 

 Seaver records (Mycologia, vi, p. 9 (1914)) that in two small 

 gatherings of this fungus in America the apothecia were only 

 about I mm. across. 



Saccobolus globulifer Bond, in Ann. Sci. Nat., 5th ser., x, p. 232 



(1S69), pi. 9, fig. XXL 



A number of specimens of this Discomycete came up on what 

 appeared to be horse dung taken from a manure heap at Leeds 

 in April 1922. Macroscopically it is indistinguishable from 

 5. violascens Boud. with which it was gromng. Characterized 

 by the balhng of the spores which when separated are seen to 

 be wedge-shaped, rough on the outside and smooth on the 

 two inner sides of the wedge, it is easily recognised under the 

 microscope. The specimens examined agree closely with Rehm's 

 description and illustration in Rabenhorst's Kryptogamen- 

 Flora, III (1894), pp. mi and 1119. 



Apothecia scattered or gregarious, sessile, cinereous violet 

 0-5 mm. broad. Asci clavate, apex blunt, base prolonged into 

 a stem, 70-90 /m long x 20-30 /n broad, 8-spored. Spores wedge- 

 shaped, smooth on the two inner sides, rough on the outside, 

 at first hyaline, passing through violet to brown when mature, 

 14-16 /x long X 7-8 /x broad, at first combined in a ball and 

 afterwards separating; the secondary membrane typical of the 

 Saccobolaceae not seen. Paraphyses filiform, septate, clavate 

 upwards, 3 jj, broad ( x 5-7 at the apex) , colourless. 



As pointed out by Rehm, his description does not wholly agree 

 with the figures in Boudier's classical monograph on the Asco- 

 bolaceae. 



REMARKS ON THE NATURE AND 

 DEFINITION OF SPECIES. 



By R. C. McLean. 



The radical difficulty besetting all classification, the delimita- 

 tion of the units employed, is nowhere more prominent or more 

 acutely felt than in mycology, where the study of the subject 

 organisms has arrived at a higher degree of intensity than 

 prevails in possibly any other plant group. This very intensity 

 of study has led to the expression of opinions antagonistic to 

 those prevailing among the majority of systematists in other 



