SYSTE5IATIC POSITIOX OF ^riTHAS TfDWX. 



hx a Tery few casos, veiT primiti^e clucis, annular or spiral, witliin the 

 traclieidal gi'uup. I cuuld not discover any trae -well-foiTQed ducts. Neither 

 sieve-tubes, nor companion cells, nor bast fibres, nor ■wood-fibres are found 

 anywhere. Tliere are one or two coUenchymatous rather rounded rectangular 

 cells near the liundles. Tlie whole tissue liko the liost itself contains a 

 considerable amonnt of tanuin. The stmcture uf tlie |)eduncles is, nyion the 

 whole, quite similar to that of Cytiim», difiering from it only in that it 

 lacks well-formed pitted or annular ducts. 



IV. Systematic Position of Mitrastevion. 



As is stated above, Mitra-stemoii beai-s a close afliuity to plants at 

 firesent referred to the Rafllesiacefo and especially to those of the Apodan- 

 theaj, a tribe of the same family. It also rosembles in some respects the 

 Nepenthacefp, Hydonoracea^, Aristolochiaceas and Balanophora- 

 cese (Makino II., p. 253). It comes near the Nepenthacepe (Wtjnsch- 

 MANn) in having single perianth and superior ovarj' ; l)ut greatly difiers 

 from it in having ^ieculiar parasitic organs, nnited stamens, one-celled ovarj' 

 ^s-ith many parietal placentas and gamophyllous perianth. It resembles the 

 HydonoraceEe (Solms-Laubach Y.) in its parasitism, its leafless, oue- 

 flowered-i^eduncles, but difiei-s in having united stamens, one-celled ovary 

 with many parietal jilacentas and ben-y-form fruit. Its affinity to the 

 Aristolochiaceae (Sou;redee) is to be seen in the gamophyllons iierianth, 

 one-ceUed ovary, beny-form frait and short columnar styles ; Irat it is quite 

 distinct in its parasitism, leafless iTediuicles and united stamens. It some- 

 ■what resembles the Balanophoracepe (Engleb) iu having a parasitic 

 habit, and scaly leafless flower-stalk ; but tlio difierence in floral stracture is 

 so great that it hardly needs pointing out. 



As ■we have seen in external as well as the internal moii>hological 

 characters, Mitrastanon lias a close relation to the RafHesiacei», in its 

 absorption-organ, miiflowered leafless j^eduncles, tetramerous iierianth, oue- 

 ceUed ovary with pai-ietal placentas, short columnar style and stigraa, and 

 in the structiu^e of its ovules. The only iwints which formerly led us to 



