Cicero “de Divinatione”, lib. 2.  “Somnium, Alexandri.  Qui, cum Ptolomaeus familiaris ejus, in proelio, telo venenato ictus esset, eoque vulnere summo cum dolore moreretur, Alexander assidens somno est consopitus; tum secundum quietem visus ei dicitur draco is, quem mater Olympias alebat, radiculam ore ferre & simul dicere quo illa loci nasceretur neque is longe aberat ab eo loco:  ejus autem esse vim tantam, ut Ptolomaeum facile sanaret.  Cum Alexander experrectus narrasset amicis somnium, emisisse qui illam radiculam quaererent.  Qua, inventa, & Ptolomaeus sanatus dicitur, & multi milites, qui erant eodem genere teli vulnerati.”

(i. e.) The dream of Alexander, when his friend Ptolemy was wounded in battle, by an envenomed dart, and died of the wound, in all the extremities of pain and anguish; Alexander sitting by him, and wearied out and quite fatigued, fell into a profound sleep.  In this sleep, that dragon is reported to have appeared to him, which was bred up by his mother Olympias, carrying a little root in his mouth and to have told him in what spot of ground it grew, (nor was it far from that very place) and told him withal it seems, that such was the force, efficacy, and virtue of it, that it would work an easy cure upon Ptolomy.  When Alexander waked, he told his friends the dream, and sent some out in quest of this little root.  The root (as story says) was found, and Ptolemy was healed, so were many soldiers likewise, that had been wounded with the same kind of darts.

Cardanus “Somniorum Synesiorum”, lib. 4, chap. 2.  “Narrat Plinius 35 lib.  Nat.  Hist, vir ab omnia superstitione alienissimus, Historiam hujusmodi.  ’Nuper cujusdam militantis in Praetorio mater vidit in quiete, ut radicem sylvestris Rosae (quam Cynorrhodon vocant) blanditam sibi aspectu pridie in Fruteto, mitteret filio bibendam:  In Lusitania res gerebatur, Hispaniae, proxima parte:  casuque accidit, ut milite a morsu Canis incipiente aquas expavescere superveniret epistola orantis ut paretet religioni; servatusque est ex insperato, & postea quisquis auxilium simile tentavit.’ "

i. e.  In his natural history, Pliny, a man the most averse to superstition, relates to us the following passage.  Lately, the mother of one of the guards, who attended upon the General, was admonished by a vision in her sleep, to send her son a draught composed of the decoction of the root of a wild rose, (which they call Cynorrhodon) with the agreeable look whereof she had been mightily taken the day before, as she was passing through a coppice.  The seat of the war at that time lay in Portugal, in that part of it next adjoining to Spain, that a soldier, beginning to apprehend mighty dangerous consequences from the bite of a dog, the letter came unexpectedly from her, entreating him to pay a blind obedience to this superstition.  He did so, and was preserved beyond all expectation; and everybody afterwards had recourse to the same remedy.