IOWA ACADEMY OF SCIENCE 
61 
IODANTHUS T. & G. 
455. Iodanthus pinnatifidus (Michx) Steud. Purple or False Rocket. 
Scarce in waste places along streams. 
DENTARIA (Tourn) L. 
456. Dentaria laciniata Muhl. Pepper-root or Toothwort. Common 
in woodlands. 
CARD AMINE (Tourn) L. 
457. Cardamine bidbosa (Schreb) BSP. Spring Cress. Common in 
bogs and springs. 
458. Cardamine pennsylvanica Muhl. Pennsylvania Bitter Cress. 
Common in moist soils. 
ARABIS L. 
459. Arabis dentata T. & G. Toothed Rock-cress. Not rare in wood- 
lands. 
460. Arabis canadensis L. Sickle-pod. Very common in rocky woods. 
461. Arabis laevigata (Muhl.) Poir. Smooth Rock-cress. Not un- 
common in woodlands. 
462. Arabis hirsuta (L.) Scop. Plairy Rock-cress. Not uncommon. 
463. Arabis drummondi Gray. Drummond’s Rock-cress. Rare in 
rocky wooded places: State Quarries. 
CAPP ARID ACE AE . 
POLANISIA Raf. 
464. Polanisia graveolens Raf. Clammy Weed. Rather scarce in 
sandy soils. 
465. Polanisia trachysperma T. & G. Large-flowered Clammy Weed. 
In similar places. 
CRASSULACEAE. 
PENTHORUM (Gronov) L. 
466. Penthonm sedoides L. Ditch Stonecrop. Common along ditches 
and in moist soils. 
