Gymnospermse, Cycadinse, Gnetaceae, Ephedra. 135 



Gen. Pityoxylon Kraus, loc. cit , p. 6. 



Lignum stratis concentricis angustis, latioribusve; cellulis pros- 

 enchymatosis porosis, poris magnis, rotundis, uni-vcl pluriserialibus, 

 oppositis; cellulis ductibusquo resiniferis haud raris ; radiis meduUa- 

 ribus compositis ductumque resiniferum includentibus vel simplicibus, 

 cellulaj eorum haud raro biformes. 



1. Pityoxylon pineoides Kraus, 1. c, pag. 7, t. I, f. 1-3. — Stratis -i^o 

 annuis 22 in fragineiito 11 mm. diam.; tracheidibus 27 y.. diam , 

 areolis punctatis tantuni radialibus, notatis; radiis medullaribus e 

 cellulis 27 v.. diam., constitutis, 8-12 cellulis alt. ; ductis resinife- 



ris 137-274 a. diam., cellulis ventricosis limitatis. 

 In sulphure insulse Sicilice (Kraus). 



2. Pityoxylon pinastroides Kraus, I. c, pag. 10, t. I, f. 4. — Stra- 470 

 tis annuis distinctis sed intei- compressis, 12-20 tracheidum series 

 latis; tracheidibus circ 24-26 [j.. diam., eleganter striatis, unise- 

 riatim areolato-punctatis; radiis medullaribus e cellulis copiose po- 

 rosis formatis, cellulis 6-10 v. etiam 14 altis; ductis resiniferis 

 paucis, compressis. 



In sulphure insulae Sicilicn (Kraus). — Species ob poros nume- 

 rosos cellularum medullarium mox distincta, cura viventibus Pino 

 hrutia et P. mariiima comparanda. 



Fam. GNETACE^ 



Gen. Ephedra Tournef., CoroII., p. 53, t. 477. 



Frutices vel suffrutices ramosissirai, praeprimis in arenosis mari- 

 timis climatis temperati incol v, ramis gracilibus erectis vel pendulis, 

 subfasciculatis, articulatis. Folia squamiformia, minima, ad articulos 

 opposita, basi in vaginam connata. Amenta mascula ovoidea, e bra- 

 cteis quadrifariam imbricatis coraposita. Flores feminei in pedicellis 

 axillaribns terminales, intra involucrum diphyllum, bracteis decus- 

 satim oppositis cinctum gemini. Ovaria duo, contigua, libera, apice 

 aperta. Ovulum solitarium erectum. Strobilus (galbulus) parvulus, 

 subglnbosus, basi squaraosus, involucris squamis carnosis incrassatis, 

 et carpidiis duobus coriaceis, dorso convexis, facie complanatis. Se- 

 mina intra carpidia solitaria e basi erecta; testa tenuiter m(;mbranacea. 



1. Ephedra 80tzl(iana (Ung.) Schimp., Tr. pnl. veg., v. II, p. 362. Ephe- 471 

 (Iritcs sofzkiaonis lleer in Capell., Calc di Leitha 1878, Atti d. 



