74 ANALES DE LA SOCIEDAD CIENTÍFICA ARGENTINA 



HYDNEAE FR. 



64. Hydnum (Pleurotus) flavum SwartzrzBERK. Ann. of Nat. Hyst. 



1842, X, p. 380. 



Hab. Ad truncos emortuos in sylvis prope Paraguari, Maj. 1883 

 (sub num. 3914). 



Obs. Pileus ecucullato explanatus semiorbicularis v. subdimidiato- 

 expansus (2-5 cent, diam. — 1,5-3 cent. lat. ant.-post.), mem- 

 branaceo-subcoriacellus (0,2 mllm. crass.), rigidulus (in sicco), 

 laevissimus, glaberrimus, fulvo-lutens v,fusco-aurantiacus, mar- 

 gine integro,, recto, vix attenuato, saepius fusco-rubescente, po- 

 stice truncato-rotundatus, semper inferné stricte sed manifestis- 

 sime marginatus, ac ibi pedicello dorsali, minuto quandoq.ue 

 perfecto evoluto, quanduque vix manifestó ac tuberculiformi, 

 terete, glabro, pileo concolore ornatus; hymenium albescenti- 

 fulvum V. pallescens planum, aculéis minutissimis (150-200 

 long. — 20-30 crass.), ómnibus aequalibus, laxe confertis ri- 

 gidulis, subsuccineis, e conoideo teretibus, glaberrimis, ápice 

 acutis V. subfimbriato-pall-escentibus vestitum, usque ad mar- 

 ginem productum ac fertile. 



Species pulchella et distinctissima aculéis abrupte ex hyme- 

 nio plano exsurgentibus; stipes saepius definite manifestus sub- 

 dorsalis, ac inferné semper stricte marginatus. 



65. Hydnum (Pleurotus?) guaraniticum Speg. (n. sp.) 



Dtag. Pileus dimidiato-expánsus (3-4 cent. diam. — 1,5-2,5 cent, 

 lat. ant.-post.), coriaceo-membranaceus (0,4-0,5 mllm. crass.), 

 fiexilis sed non flaccidus, applanatus, margine recto, acuto, in- 

 tegerrimo, postice truncato-subreniformis, ibique vix, sed in 

 dorso, stipitatus v. tuberculato-adnatus, minute adpresseque 

 velutinus (fere tantum tactu), postice sórdido pallescenti-car- 

 neus ac saepe obsoleto conceutrice zonatus v. undulatus, mar- 

 ginara versus fulvescenti-albescens v. alutaceus, intus concolor, 

 fibroso-flocculosus, compactiusculus ; hymenium albidum, acu- 

 léis confertiusculis, ex albido griseo-carneis, subceraceo-tena- 

 cellis, conico-teretibus, albis, pruinula carnea conspersis, lon- 

 giusculis (0,5-0,7 mllm. long. — 0,15 crass.), ápice obtusiu- 

 scule acutatis, marginem versus gradatim abbreviatis, ac zona 



