▁have ▁small ▁sharp ▁or ▁rounded ▁teeth . ▁The ▁tips ▁of ▁the ▁pin na e ▁vary ▁from ▁bl unt ▁to ▁sharp . ▁ ▁On ▁the ▁unders ide ▁of ▁the ▁bl ades , ▁the ▁ve ins ▁are ▁mostly ▁free ▁and ▁rarely ▁an ast om ose ▁( re connect ▁with ▁each ▁other ). ▁The ▁fert ile ▁bl ades ▁bear ▁from ▁one ▁to ▁ten ▁( rare ly ▁fifteen ▁or ▁more ) ▁s ori ▁per ▁pin na ▁or ▁lo be ; ▁the ▁s ori ▁are ▁found ▁along ▁the ▁whole ▁length ▁of ▁the ▁leaf . ▁In ▁A .   ×   eben o ides ▁( as ▁distinct ▁from ▁A .   t ut w il era e ), ▁the ▁ster ile ▁sp ores ▁are ▁mal formed , ▁although ▁vi able ▁sp ores ▁can ▁apparently ▁form ▁by ▁ap og amy ▁on ▁rare ▁occasions . ▁The ▁s ori , ▁ ▁long , ▁are ▁covered ▁by ▁thin , ▁wh it ish ▁ind us ia ▁with ▁irregular , ▁rounded ▁teeth . ▁The ▁tip ▁of ▁the ▁bla de ▁sometimes ▁be ars ▁a ▁bud ▁similar ▁to ▁those ▁formed ▁by ▁A .   rh iz oph yll um . ▁These ▁can ▁develop ▁into ▁mini ature ▁plants , ▁which ▁are ▁not ▁known ▁to ▁take ▁root ▁in ▁nature , ▁although ▁they ▁have ▁been ▁propag ated ▁in ▁culture . ▁ ▁The ▁species ▁most ▁similar ▁to ▁A .   ×   eben o ides ▁is ▁A .   t ut w il era e , ▁long ▁considered ▁cons pec ific ▁and ▁only ▁found ▁at ▁Hav ana ▁Glen , ▁Alabama .