168 



J. O. HAOSTRÖM, CRIT1CAL RESEARCHES ON THE POTAMOGETONS. 



Stem terete, its epidermis lacking a pseudo-hypoderma but with numerous, rather 

 strong, mechanic strands. Cortically and interlacunarly there are always a few 

 (3 — 6) vascular and bast bundles. Central stele of roundish crosscut-form and with 

 8 free bundles encompassed by strong, more or less open bast-sheaths. The arrange- 

 ment of the bundles becomes apparent by the diagram above. The median bundles are 

 merely two as in P. tricarinatus (eight-bundled type). The lacunar system is the 

 usual: 3 — 4 circles of lacunse, the outer relatively large, the inner ones narrower. 



Distribution. Australia. The label bears only this annotation: — Nov. Hol- 

 land, meridional. Planta? Miillerianae. (Hb. Lund.). 



I\ spoliiltlis n. sj). 



Fig. 85. 



cc 



ooQbi 



, Qo.oQfW 



Caulis 0,5 m altus et ultra, teres 

 subcrassus simplex, internodiis 3 — 6 cm 

 longis, ramo uno prolongatus. Folia 

 superiora coriacea lanceolata vel ovali- 

 lanceolata, mucrone obtuso, 15— 18-ner- 

 via, 40 — 60 X ± 20 mm, late petiolata, 

 petiolis foliorum floralium ca. 30 mm 

 longis. Ligulai basi subcostata? membra- 

 nacerc cito putrescentes, summa 1 40 — 45 

 mm longse. Pedunculus a?qualis 55 mm 

 longus. Spica densa multiflora, deflo- 

 rata 35 mm longa. Pistilium stylo 

 elongato stigmate oblongo. 



This species is characterized by the 



l i| . B5. /'. spoliatiu Bagstb. .-1, Involnoral leaf, [. H. Pistil, 

 r,\ .-ir> ii little grcrwu ont, ',". C, TransverBe section of stem, 3 ,°> 

 ep, epidermis, hyp, psendo-faypoderma, rtr, Bnbepidarmal Btrand, i, sllOrt-petioled lipper leaves, VC1\V SOOI1 

 interlaconar bnndle, ee, central cvlinder, tv, trio-bondle. . . . 



decaying lower leaves, and the noticeable 

 pistil (see the fig!). Already in an early stage the lower leaves fade away and the 

 plant, therefore, presents a poor and naked appearence, so much the more as it is 

 simple all np to the primary spike. In this respect it presents a great resemblance 

 with /'. 8leno8tachys Schum. which, however, has long-petiolod leaves and very ample 

 sheaths, remarkable perianth leaves and a short fragile style. 



Stem-anatomy: The epidermis is strengthened by a pseudo-hypoderma and 

 scattercd bast-bundles. Jnterlacnnar bundles in the cortex in one circle always pre- 

 sent. Outer lacunae of the cortex oonsiderably wider t han i\\c inner <>nes. Endo- 

 dermifl of O-cells and the central stele with eight free vascular bundles with equal 

 numbei of xylem canals. Bundle-trio reduced to a compound bundle with thrcc 

 phloem parts and interjacent bast-cells. By those anatomic conditions it diflcrs from 

 /'. marUemdenaie, whieh for instanoe lacks both Btrengthening layer and sub(>i)i- 

 dcrnial si lands. 



