142 FUNGI. [Polijporus. 



On dead fir-trees ; commox\.—Pileus 1—2 inches across, sometimes 

 entirely resupinate with the exception of the extreme margin and spread- 

 ing over several inches ; more generally effuso-reflexed, thin, coriaceous, 

 zoned, whitish, often stained with minute green Algce, more or less 

 villous. Pores very irregular, laciniated, sometimes resemhling hydnoid 

 teeth, more or less of a violet hue, which fades when the plant is past 

 maturity. 



-5 — \ 1- Bieimial or Perennial. 



26. P. idmdrms, Sow. {Elm-tree Polyporiis) ; pileus between 

 flesiiy and corky zoneless smooth whitish, pores small at first 

 bright tawny. Fr. Syst. Myc. v. 1. p. 3G5 — Bol. ulmarius, 

 Sow. t. 88. 



In hollow elms ; not common. Madingley, Cambridgesh. ; Chis- 

 wick, Middlesex. Rev. M. J. Berkelei/.— Effused, with an obtuse 

 occasionally free margin, forming a new stratum every year, so that a 

 section gives several distinct layers of pores and flesh alternating with 

 each other. Flesh white. Pores minutely tawny. Substance, when 

 dry, hard and corky. A very distinct species. 



27. P. Scoticnsy Klotzscli, {brown stratifed Polyporus) ; effused 

 or effuso-reflexed margined brownish zoned, pores white. 

 Klotzscli T4SS. in Hook. Herb. 



About the roots of trees : not uncommon in England and Scotland. 

 — Forming masses 3 — 18 inches wide, of imbricated, rugged or radiato- 

 striate brown jrdci, occasionally tawny towards the margin, marked with 

 strong, vaulted zones which arise from each annual layer projecting 

 beyond that of the preceding year. Substance white, hard and woody. 

 Pores middle-sized,.white, or'with a pale reddish-brown tint, margined 

 above as well as below, so that each layer appears resupinate — This 

 species, which seems to have almost every point in common with P. 

 resinosus, and is distinguished from it chiefly by its longer duration, is 

 named by Klotzsch in Hook. Herb., P. Scoticus. A more appropriate 

 name might certainly be found, but as it is possible that he may have 

 published^ this, as well as many other new species, from Dr. Hooker's 

 Herbarium, I consider it proper_to retain it. 



28. P. cytisi?nis, B^vk. {Laburnum Polyporus) ^ large imbri- 

 cated, pileus coarsely tuberculated, margin subacute, substance 

 very close but composed of velvety fibres nearly ^yhite as M'ell 

 as the minute pores Bol. suberosus, Soiv. t. 288. 



At the foot of a Laburnum near London, where another specimen is now 

 growmg on the same portion of the trunk from whence my specimen was 

 gathered. Mr. C. Sowerby.— lmhncnted, above a foot across, dimidiate, 

 quite smooth (at least when dry) but coarsely tuberculated. Substance 

 slightly zoned, very thick and close, pale, evidently composed of two or 

 three successive layers. This is certainly the same as B. suberosus^ 

 Sow., though the texture of that seems 'a little more wo^dy and the 

 dried specimen now before me is reddish, which, however, may arise 

 from its having been impregnated with oil, which appears sometimes to 

 have been Mr. Sowerby's practice for the preservation of specimens. 

 The only species at all according with it is P. rnarginatiis, but that 

 appears to be of quite a different colour. I can find no notice of Sowerby's 

 figure in the Syst. Myc. 



29. P. fraxineus, Bull. (Ash-tree Polyporus) ; hard, pileus 



