I would like to dedicate this post to analyze, even if briefly, role and meaning of a very important Divine Force structured into two polarities: the male (Pluto) and the female (Proserpina) polarity.
Probably these are the best known infernal polarities but too often they are quite equivocated also under the influence of many monoteist prejudices. It is important to remind that the Idea of Inferi, according to the Traditional Roman Spirituality, is completely different from the idea of Hell of the monoteism (under many points of view they are rather anthitetical).
"Nothing can last forever: without the Death, there's no Life": this sentence exemplifies the cycle of the existence and the essence of the Inferi as place of Death and Life generation. Similarly Pluto and Proserpina embrace elements of Life and Death.
Tradition indicates that Proserpina is a force related to seeds: Pluto is "Sun proceeding underground: he visits the invisible world during the winter solstice" (Porphiry, Peri Agàlmaton).
Proserpina has a complex symbolism linked to the buds' cropping out: from this reason she has two horns and the female appearance evidencing her generating force. Proserpina is the force at the base of the seeds' growth (she is Ceres' daughter).
She wears a crown made of ears of wheat (basic food for mankind): she is surrounded by poppies (symbol of the Earth). Poppy is symbol of married love and fecundity. Poppy is an infernal plant because it is the symbol of sleep and death.
The myth of Proserpina represents the alternating of the seasonal cycles on Earth and all the processes of "rebirth" (palingenesis)
Pluto is represented by the helm (as representation of the invisible world and invisibility) and by a half-scepter. The lack of the scepter's peak is the symbol of his sovereignty on the Inferi World (The Under-World), the lack of the "Above": his autority is not related to the "Above". He wears a purple cover: purple is the colour of the Underworld representing light descending underground. Pluto has the scepter in his left hand and in his right hand he holds a horn of plenty (Richness), or a Key (Initiation symbol as well as symbol of the control of the Underworld).
Cerberus, the Pluto/Proserpina dog, has three heads to evidencing the three phases in the existence formation: seeding, receiving and growth. He also represents the three main sky regions: East, South and West. Pluto, sometimes standig up or sitting on a throne, keeps his right hand over the Cerberus' heads to remark his total control.
Black animals, snakes and cypress are sacred to Pluto/Proserpina, but the tree highly representing Pluto/Proserpina is the pomegranate whose fruit, which can be harvested in October and November, remarks the "link" with the Underworld.
The pomegranate is the symbol of the "link", above all the "Blood Link": this fruit is the symbol also of fecundity, richness, abundance. In addition the pomegranate represents the "rebirth" and initiation.
Richness and abundance in agriculture depends on the Pluto's Force. But, as already mentioned, Pluto and Proserpina embody also the Power of the Death without which it is not possible to generate new life. Pluto and Proserpina are therefore destroyng and creating forces in the same time. After all the palingenesis is impossible without the involvement of a preliminary "death" as precondtion of the complete abandoning of the profane existence. Being at the base of the Mysteries of Eleusis, the greater part of the symbolism and rituals of Proserpina and Pluto was (and still is) secret and it is not licit to talk about them extensively.
Pluto and Proserpina can be invoked beating the hands over the ground.
In the ancient Rome Pluto and Proserpina had a specific underground Temple in the Tarentum (or Terentum).