I found some plants with that name but that doesn't seem right. Is it an older name for an animal part?
The Latin text is "super arietem cicer arietinum", which can be literally translated as "on the [Zodiac sign of] Aries, ram's chickpeas". Therefore, one possibility is that "ram's vetches" is a chickpea dish of some kind. The connection with Aries seems rather tenuous if it is a chickpea dish. Notably, one variety of chickpea was called "arietinum", for the resemblance to a ram's head. As noted in Pliny's Natural History,
One variety resembles in shape a ram's head, from which circumstance it has received the name of "arietinum;" there are both the white and the black arietinum.
However, "cicer" was also a slang term meaning "testicle", with a fairly straightforward origin of this as a slang term being suggested by the somewhat scrotal appearance of a chickpea pod:
If the dish was "ram's testicles", then it is very appropriate for Aries. The "arietinum" chickpea is also appropriate.
If we look at all of the listed dishes:
Rotundum enim repositorium duodecim habebat signa in orbe disposita, super quae proprium convenientemque materiae structor imposuerat cibum: super arietem cicer arietinum, super taurum bubulae frustum, super geminos testiculos ac rienes, super cancrum coronam, super leonem ficum Africanam, super virginem steriliculam, super libram stateram in cuius altera parte scriblita erat, in altera placenta, super scorpionem pisciculum marinum, super sagittarium oclopetam, super capricornum locustam marinam, super aquarium anserem, super pisces duos mullos. In medio autem caespes cum herbis excisus favum sustinebat.
(Latin text from here) English translations vary. For example, the translation from here:
There was a round plate with the twelve signs of the Zodiac set in order, and on each one the artist had laid some food fit and proper to the symbol; over the Ram ram's-head pease, a piece of beef on the Bull, kidneys over the Twins, over the Crab a crown, an African fig over the Lion, a barren sow's paunch over Virgo, over Libra a pair of scales with a muffin on one side and a cake on the other, over Scorpio a small sea-fish, over Sagittarius a bull's-eye, over Capricornus a lobster, over Aquarius a goose, over Pisces two mullets. In the middle lay a honeycomb on a sod of turf with the green grass on it.
There was a circular tray around which were displayed the signs of the zodiac, and upon each sign the caterer had placed the food best in keeping with it. Ram’s vetches on Aries, a piece of beef on Taurus, kidneys and lamb’s fry on Gemini, a crown on Cancer, the womb of an unfarrowed sow on Virgo, an African fig on Leo, on Libra a balance, one pan of which held a tart and the other a cake, a small seafish on Scorpio, a bull’s eye on Sagittarius, a sea lobster on Capricornus, a goose on Aquarius and two mullets on Pisces. In the middle lay a piece of cut sod upon which rested a honeycomb with the grass arranged around it.
give a good indication of the variety. The Gemini dish is testicles and kidneys, both paired organs. An African fig, while being African to suit a lion, is not particularly leonine. "ficus" does have an alternative slang meaning, of "hemorrhoids", but seems unlikely as a dish.
For more discussion of these dishes, see
For an excellent translation resource for this passage, see
