Rav Heshi, it is great to hear from you again!

1) The Me'iri writes, as a possible answer, that there may be a small fish which expands greatly when it swallows, and is able to hold a large quantity. He writes that this is like what one sees when a leech sucks blood, that it broadens out on all its sides.

2) I do not know if we can identify the small fish that expands greatly enough to swallow a man, but I have read that leeches can expand to up to ten times their size when they suck blood, and I also read that the puffer fish can expand to three times its size. That still would not be large enough to swallow a human, but we can get an idea that it may be possible that there was a species that expanded more than that, and possibly later became extinct.

3) None of the other Rishonim seem to say something similar to the Me'iri, so we will have another look at the Sugya, bs'd.

a) Your question -- that the fact that it says the word "Gadol" may actually prove the opposite -- is asked by the Melo ha'Ro'im, printed at the back of the Gemara. He compares this to the Gemara in Sotah 2b, which says that wherever the Torah uses the word "Ed," this means two witnesses unless it states explicitly one.

b) The Melo ha'Ro'im answers that it is possible that one can only make this sort of Diyuk when the Torah is stating Dinim but not when it is telling us a story, as in the case of Yonah.

c) I want to suggest a different answer to this question, bs'd. Rav Papa's Diyuk is from the fact that the vere does not state "Dagah Gedolah." If it would have said that, we would have known that "Dagah" means a big fish.

Therefore, I argue that when the Gemara cites the verse that Yonah davened from inside the Dagah, this means -- according to the question of the Gemara -- that "Dagah" could mean specifically a big fish, not either large or small.

d) To answer your question from the next verse, "va'Yomer Hash-m la'Dag," I want to say a big Chidush. Yonah was expelled by the Dagah, and then swallowed, for the third time, by a Dag!

4) After further research, I found, bs'd, that I was not so far off the mark in what I wrote above, but we should look at what the Midrash says about what happened to Yonah inside the fish.

a) This is from Yalkut Shimoni to Yonah 2:3 (the Maharsha here cites the Midrash). The Midrash tells us that Yonah entered the fish like one enters a big Beis ha'Kneses. It was spacious and comfortable and he was in the fish for three days and three nights and did not pray to Hash-m. Hash-m said, "I will make it less comfortable for Yonah, so that he will have to pray, because Hash-m desires the prayers of the righteous." Hash-m brought along a Dagah, pregnant with an incredible amount of little fish. The first fish spat out Yonah and the pregnant Dagah swallowed him. It was very crowded and dirty for Yonah inside the second fish and now he had Kavanah and prayed.

b) The Maharsha here asks the question, why does the verse later on say that Hash-m told the Dag to spew out Yonah? Why does it not say that He told the Dagah? Maharsha writes that one could say that after Yonah prayed, the Dagah put Yonah back into the mouth of the Dag, but he writes that he does not know why the Dagah did not put Yonah directly back on dry land.

c) The Metzudos David to Yonah 2:11 writes that after Yonah prayed, it is probable that the reason the Dagah put him back in the mouth of the Dag was so that Yonah could again stand there with plenty of room.

d) It seems to me that the Metzudas David is referring to the Midrash which stated earlier that Hash-m told a big Dag to swallow Yonah so that it should be spacious for him and he should not suffer dicomfort. But the problem was that because he was so comfortable, he did not pray, and Hash-m loves to hear the prayers of the Tzadikim, so He placed him in an uncomfortable Dagah. Now that Yonah had prayed, Hash-m returned him to the comfortable Dag so that Yonah should know that the reason why Hash-m put him in

5) The Chidushei Chasam Sofer gives two reasons for why Hash-m told the Dag, not the Dagah, to eject Yonah. One reason is according to the original understanding of the Gemara, and the second reason is according to the conclusion.

a) The way the Gemara understood, on the first wide line, is that a bigger fish ejected Yonah and a smaller fish then swallowed him. However, it is all relative, and the second fish was also big (a lot bigger than a Litra) and was only called "Dagah" in comparison to the first one. Therefore, it is not difficult that the verse concludes that Hash-m told the Dag to eject Yonah, since the second fish was also big enough to be called a Dag and was only described as Dagah the first time because it was being compared to the first, even bigger, fish.

b) The conclusion of this story, however, fits with what the Midrash says -- that the second fish was called "Dagah" because it was a female. But the Talmud Yerushalmi, at the beginning of the seventh chapter of Maseches Sotah, tells us that the only woman that Hash-m ever spoke to was Sarah. Therefore, it could not say that Hash-m "said to the Dagah." The Chasam Sofer writes that the verse (Yonah 2:11) that states that Hash-m "said to the Dag" means that he spoke to the upper Sar, who is appointed over the fish.

Kol Tuv,

Dovid Bloom