Reproduction
The basic structure of the reproductive tract is similar in both sexes, with a mesodermal gonoduct (sperm duct or oviduct) emerging from both sides of the U-shaped gonad (testis or ovary). The two gonoducts fuse into a single duct, which leads into a cuticle-lined duct derived from the ectoderm into the open through an organ (penis or ovipositor) that can be everted through a combination of muscles and hemolymph pressure. These eversible organs play an important role in determining taxonomic relationships.
The penis is often complex, consisting of a long shaft and a shorter glans at the end, which is often equipped with various projections such as spines. In many species muscles move the glans relative to the shaft, but in Grassatores these muscles are lacking, and the movement is achieved purely by hydraulic means. A muscular propulsive organ, which pushes the ejaculate out, is missing in Cyphophthalmi, which have very short penises. The ovipositor is originally segmented and long, but has been reduced in several groups.
Read more about this topic: Harvestman Anatomy
Famous quotes containing the word reproduction:
“Were I called on to define, very briefly, the term Art, I should call it “the reproduction of what the Senses perceive in Nature through the veil of the soul.” The mere imitation, however accurate, of what is in Nature, entitles no man to the sacred name of “Artist.””
—Edgar Allan Poe (1809–1845)
“It is so characteristic, that just when the mechanics of reproduction are so vastly improved, there are fewer and fewer people who know how the music should be played.”
—Ludwig Wittgenstein (1889–1951)
“The atmosphere parents wish to create when talking with children about birth and reproduction is warm, honest, and reassuring, one that tells children they are free to ask questions as often as they need to, and you will answer them as lovingly as you know how.”
—Joanna Cole (20th century)