Blavatsky gives a very intriguing and intricate mini-essay on the symbolism of Capricorn
(SD 2, 24, pp. 576-580, 'The Cross and the Pythagorean Decade')http://www.theosociety.org/pasadena/sd/sd2-2-11.htm
and gives a few additional hints in the Theosophical Glossary:
"Capricornus (Lat.) The 10th sign of the Zodiac (Makâra in Sanskrit), considered, on account of its hidden meaning, the most important among the constellations of the mysterious Zodiac. it is fully described in the Secret Doctrine, and therefore needs but a few words more. Whether, agreeably with exoteric statements, Capricornus was related in any way to the wet-nurse Amalthæa who fed Jupiter with her milk, or whether it was the god Pan who changed himself into a goat and left his impress upon the sidereal records, matters little. Each of the fables has its significance. Everything in Nature is intimately correlated to the rest, and therefore the students of ancient lore will not be too much surprised when told that even the seven steps taken in the direction of every one of the four points of the compass, or —28 steps—taken by the new-born infant Buddha, are closely related to the 28 stars of the constellation of Capricornus." (Blavatsky, Theosophical Glossary)
Moreover, certain explanations on the symbolism of Scorpio, I think, can be considered complementary:
"For the zodiacal sign of the tribe of Dan was Scorpio, as all know; and Scorpio is the sign of the female procreative principle, the matrix, and even geographically the heirloom of the tribe of Dan was the place of Dan, which included that of the springs or sources of Jordan, whose waters flowed out of the bowels of the earth. As the Styx with the Greeks, which, during the mystery trial by water, played a like part in the crypts of the temples, so the whale or fish that swallowed Jonah in the Old Testament, and Jordan that immersed Jesus in the New—all of these great “deeps” and small “deeps,” the interior of fish, waters, etc., all typified the same thing. They signified entering into conditions of existence by death, which became a new birth. As Jonah, the Initiate of the Old Testament, enters the womb of the whale (Phallic Initiation), so Jesus, the man, entering the water (the type of the spiritual womb of his second birth) enters Jar-Dan, the river of Dan, the tribe which astronomically was in Scorpio (the “gates of woman,” or the matrix). Emerging from it, he became Christos, the glorified Initiate, or the divine and sexless androgyne. So also, Jonah, upon emerging, became the “Lord,” with the Jews Jah-hovah; thus preceding Jes-us, the new life. The Jesus of the New Testament becomes the anointed by the Spirit, symbolized by the Dove. For John, Oannes, or Jonah, or the Whale-Fish, the emblem of the terrestrial world of the Old Dispensation, is transformed into the Dove, over the waters, the emblem of the Spiritual World. As said by Nigidius:
The Syrians and Phoenicians assert that a dove sat several days in Euphrates [one of the four rivers in Eden] on the egg of a fish, whence their Venus was born.*" [Blavatsky, NOTES ON THE GOSPEL ACCORDING TO JOHN Lucifer, Vol. XI, No. 66, February, 1893, pp. 449-456, CW XI, 496]
(SD 2, 24, pp. 576-580, 'The Cross and the Pythagorean Decade')http://www.theosociety.org/pasadena/sd/sd2-2-11.htm
and gives a few additional hints in the Theosophical Glossary:
"Capricornus (Lat.) The 10th sign of the Zodiac (Makâra in Sanskrit), considered, on account of its hidden meaning, the most important among the constellations of the mysterious Zodiac. it is fully described in the Secret Doctrine, and therefore needs but a few words more. Whether, agreeably with exoteric statements, Capricornus was related in any way to the wet-nurse Amalthæa who fed Jupiter with her milk, or whether it was the god Pan who changed himself into a goat and left his impress upon the sidereal records, matters little. Each of the fables has its significance. Everything in Nature is intimately correlated to the rest, and therefore the students of ancient lore will not be too much surprised when told that even the seven steps taken in the direction of every one of the four points of the compass, or —28 steps—taken by the new-born infant Buddha, are closely related to the 28 stars of the constellation of Capricornus." (Blavatsky, Theosophical Glossary)
Moreover, certain explanations on the symbolism of Scorpio, I think, can be considered complementary:
"For the zodiacal sign of the tribe of Dan was Scorpio, as all know; and Scorpio is the sign of the female procreative principle, the matrix, and even geographically the heirloom of the tribe of Dan was the place of Dan, which included that of the springs or sources of Jordan, whose waters flowed out of the bowels of the earth. As the Styx with the Greeks, which, during the mystery trial by water, played a like part in the crypts of the temples, so the whale or fish that swallowed Jonah in the Old Testament, and Jordan that immersed Jesus in the New—all of these great “deeps” and small “deeps,” the interior of fish, waters, etc., all typified the same thing. They signified entering into conditions of existence by death, which became a new birth. As Jonah, the Initiate of the Old Testament, enters the womb of the whale (Phallic Initiation), so Jesus, the man, entering the water (the type of the spiritual womb of his second birth) enters Jar-Dan, the river of Dan, the tribe which astronomically was in Scorpio (the “gates of woman,” or the matrix). Emerging from it, he became Christos, the glorified Initiate, or the divine and sexless androgyne. So also, Jonah, upon emerging, became the “Lord,” with the Jews Jah-hovah; thus preceding Jes-us, the new life. The Jesus of the New Testament becomes the anointed by the Spirit, symbolized by the Dove. For John, Oannes, or Jonah, or the Whale-Fish, the emblem of the terrestrial world of the Old Dispensation, is transformed into the Dove, over the waters, the emblem of the Spiritual World. As said by Nigidius:
The Syrians and Phoenicians assert that a dove sat several days in Euphrates [one of the four rivers in Eden] on the egg of a fish, whence their Venus was born.*" [Blavatsky, NOTES ON THE GOSPEL ACCORDING TO JOHN Lucifer, Vol. XI, No. 66, February, 1893, pp. 449-456, CW XI, 496]