102 
ADA HAYDEN 
Subterranean Stems 
Name 
Habitat 
Su.t)tcrr3.nc3.n 
Stem 
Radial 
Depth 
Cortex 
Parenchyma 
IVIcchs-nicsl 
Tissue 
Vascular Tissue 
T'vhhn. 
J. y jyrt'U/ 
Al. bas. 
R li 1 7r> m p 
1/2 
Aerenchyma 
micrlrf" in A/^iQ 
Oll&HC 111 Vdo* 
Fairly 
In fi folia 
VilinrI c:Vip^i1"li 
Iw'LJ.llVJ.a oll^ClLll 
pujllllllcH L 
P hra^mites 
Al. bas. 
Rhizome 
1/2 
Aerenchyma 
Slight 
Spartina 
Al. bas. 
Rhizome 
3/7 
Slight 
Prominent 
Vas. bundles 
Michauxiana 
large, numerous 
Pfi'H'iriJ'yyi 
Al. bas. 
2/9 
Slight 
Prr»m 1 n pn 1" 
\/ G ]~mnrl1pc 
uirontu'm 
large 
Scirpus 
Al. bas. 
Rhizome 
1/2 
Aerenchyma 
In vas.bund. 
Vas bundlps 
veto. I^Llll^lt-O 
fluviatilis 
sheaths 
numerous 
Scirpus 
Al. bas. 
Rhizome 
1/3 
Aerenchyma 
In vas.bund. 
Prominent 
validus 
sheaths 
Iris 
Al. bas. 
Rhizome 
l/3 
Aerenchyma 
In vas.bund. 
Prominent 
versicolor 
sheaths 
Polygonum 
Al. bas. 
Rhizome 
lie 
Aerenchyma 
Absent ex- 
Slight 
Muhlenhergii 
cept few 
wood cells 
Asclepias 
Al. bas. 
Rhizome 
1/4. 
Prominent 
Absent 
Tracheae few 
verticillata 
Monarda 
Al. bas. 
Rhizome 
Prominent 
Slight 
Tracheae few 
fistulosa 
Heuchera 
Upland 
Rhizome 
Prominent 
Absent 
Trarhpflp • 
A mericana 
tissue small 
Viola 
Upland 
Rhizome 
1/4 
Prominent 
Absent 
Tracheae small, 
pedata 
numerous 
A ster 
T Tr>1;i nd 
Rhizome 
1/7 
Corlc ■slip'hl" • 
Fairly 
T^rn pVipap 
azureus 
parenchyma 
prominent 
numerous 
Antennaria 
Upland 
Rhizome 
1/4 
Moderate 
Prominent 
Tracheae small. 
plantaginifolia 
wood fibers 
inconspicuous 
Liatris 
Upland 
Corm 
1/6 
Compact 
Prominent 
Few tracheae ; 
squarrosa 
small 
Heliopsis 
Upland 
Rhizome 
1/9 
Slight 
Prominent 
Tracheae 
scabra 
numerous 
Lepachys 
Upland 
Rhizome 
1/6 
Slight 
Prominent 
Tracheae 
pinnata 
small, few 
Artemisia 
Upland 
Rhizome 
1/4 
Prominent 
Moderate 
Few tracheae 
ludoviciana 
Helianthus 
Upland 
Rhizome 
1/4 
Prominent 
Slight 
Tracheae few 
tuberosus 
prominent in 66 percent of the roots. Tracheae were generally large and 
quite numerous. 
The only thick root of the alluvial basin studied was that of Baptisia 
leucantha, which had prominent parenchyma, moderate mechanical tissue, 
and few tracheae. 
The subterranean stems of ten alluvial basin and nine upland plants 
were examined. Of the alluvial basin plants, 65 percent had aerench37ma 
and only 10 percent reduced parenchyma. In only 10 percent was mechan- 
ical tissue prominent though present about the sheaths of monocotyledons. 
In the monocotyledons the vascular tissue was fairly prominent; in dicoty- 
ledons it was poorly developed. 
In the stems of the upland plants there is considerable variation in the 
