How are the daily themes decided in the Decameron?

Question

Wikipedia claims that the topic of Day 2's stories is decreed by that day's queen, Filomena:

Filomena reigns during the second day and she assigns a topic to each of the storytellers: Misadventures that suddenly end happily.

Is this true, and when does she make such a decree? The Day 2 introduction doesn't say anything about it, and the day's first storyteller Neifile says (emphasis mine):

Often has it happened, dearest ladies, that one who has studied to raise a laugh at others' expense, especially in regard of things worthy to be had in reverence, has found the laugh turn against himself, and sometimes to his loss: as, in obedience to the queen's command, and by way of introducing our theme, I am about to shew you, by the narrative of an adventure which befell one of our own citizens, and after a course of evil fortune had an entirely unexpected and very felicitous issue.

The theme of "Misadventures that suddenly end happily" is indeed followed, but is Neifile alluding to this theme being decreed by the day's queen Filomena, or does "in obedience to the queen's command" refer to her starting her story rather than to the theme she's introducing?

Answer 1

Duh, I missed it: Filomena was appointed as the new queen at the end of Day 1, and she made her decree then:

True it is that Pampinea, by reason of her late election to the sovereignty, neglected one matter, which I mean to introduce, to wit, the circumscription of the topic of our story-telling, and its preassignment, that each may be able to premeditate some apt story bearing upon the theme; and seeing that from the beginning of the world Fortune has made men the sport of divers accidents, and so it will continue until the end, the theme, so please you, shall in each case be the same; to wit, the fortune of such as after divers adventures have at last attained a goal of unexpected felicity.

The same custom is observed by each new ruler at the end of the day before their ruling day:

3. Neifile at the end of Day 2:

   I propose, both because you will thereby have more time for thought, and it will be best to set some limits to the license of our story-telling, that of the many diversities of Fortune's handiwork we make one our theme, whereof I have also made choice, to wit, the luck of such as have painfully acquired some much-coveted thing, or having lost, have recovered it.

4. Filostrato at the end of Day 3:

   Wherefore I am minded that to-morrow our discourse be of no other topic than that which is most germane to my condition, to wit, of those whose loves had a disastrous close: because mine, I expect, will in the long run be most disastrous; nor for other cause was the name, by which you address me, given me by one that well knew its signification.

5. Fiammetta at the end of Day 4:

   And gladly take I the wreath, Filostrato, and that thou mayst more truly understand what thou hast done, 'tis my present will and pleasure that each make ready to discourse to-morrow of good fortune befalling lovers after divers direful or disastrous adventures.

6. Elisa at the end of Day 5:

   I ordain that to-morrow, God helping us, the following be the rule of our discourse; to wit, that it be of such as by some sprightly sally have repulsed an attack, or by some ready retort or device have avoided loss, peril or scorn.

7. Dioneo, somewhat controversially, at the end of Day 6:

   I ordain that, taking our cue from Madam Licisca, we discourse to-morrow of the tricks that, either for love or for their deliverance from peril, ladies have heretofore played their husbands, and whether they were by the said husbands detected or no.

8. Lauretta, in response, at the end of Day 7:

   Dioneo would have it that to-day we should discourse of the tricks that wives play their husbands; and but that I am minded not to shew as of the breed of yelping curs, that are ever prompt to retaliate, I would ordain that to-morrow we discourse of the tricks that husbands play their wives. However, in lieu thereof, I will have every one take thought to tell of those tricks that, daily, woman plays man, or man woman, or one man another; wherein, I doubt not, there will be matter of discourse no less agreeable than has been that of to-day.

9. Emilia allows everyone freedom at the end of Day 8:

   Wherefore I deem that, as for so many days our discourse has been confined within the bounds of certain laws, 'twill be not only meet but profitable for us, being in need of relaxation, to roam a while, and so recruit our strength to undergo the yoke once more. And therefore I am minded that to-morrow the sweet tenor of your discourse be not confined to any particular theme, but that you be at liberty to discourse on such wise as to each may seem best; for well assured am I that thus to speak of divers matters will be no less pleasurable than to limit ourselves to one topic; and by reason of this enlargement my successor in the sovereignty will find you more vigorous, and be therefore all the more forward to reimpose upon you the wonted restraint of our laws.

10. Panfilo at the end of Day 9:

    Enamoured my ladies, Emilia, our queen of to-day, deeming it proper to allow you an interval of rest to recruit your powers, gave you license to discourse of such matters as should most commend themselves to each in turn; and as thereby you are now rested, I judge that 'tis meet to revert to our accustomed rule. Wherefore I ordain that for to-morrow you do each of you take thought how you may discourse of the ensuing theme: to wit, of such as in matters of love, or otherwise, have done something with liberality or magnificence.