rhamphotheca:

Book Lungs
A book lung is a type of respiration organ used for atmospheric gas exchange and is found in arachnids, such as scorpions and spiders, and horseshoe crabs.  Each of these organs is found inside a ventral abdominal cavity and  connects with the surroundings through a small opening. Book lungs are  not related to the lungs of modern land-dwelling vertebrates.
Their name describes their structure. Stacks of alternating air pockets  and hemolymph-filled tissue give them an appearance similar to a  “folded” book. Their number varies from just one pair in most spiders to four pairs in  scorpions. Sometimes the book lungs can be absent and the gas exchange  is performed by the thin walls inside the cavity instead, with its  surface area increased by branching into the body as thin tubes called tracheae.  It is possible that the tracheae have evolved directly from the book  lungs, because in some spiders the tracheae have a small number of  greatly elongated chambers.
Many arachnids, like mites and harvestmen (Opiliones), have no traces of book lungs and breathe through tracheae or through their body surface only…
(read more: Wikipedia)
image from: The Spider Book (1920 ed.) by John Henry Comstock

rhamphotheca:

Book Lungs

A book lung is a type of respiration organ used for atmospheric gas exchange and is found in arachnids, such as scorpions and spiders, and horseshoe crabs. Each of these organs is found inside a ventral abdominal cavity and connects with the surroundings through a small opening. Book lungs are not related to the lungs of modern land-dwelling vertebrates.

Their name describes their structure. Stacks of alternating air pockets and hemolymph-filled tissue give them an appearance similar to a “folded” book. Their number varies from just one pair in most spiders to four pairs in scorpions. Sometimes the book lungs can be absent and the gas exchange is performed by the thin walls inside the cavity instead, with its surface area increased by branching into the body as thin tubes called tracheae. It is possible that the tracheae have evolved directly from the book lungs, because in some spiders the tracheae have a small number of greatly elongated chambers.

Many arachnids, like mites and harvestmen (Opiliones), have no traces of book lungs and breathe through tracheae or through their body surface only…

(read more: Wikipedia)

image from: The Spider Book (1920 ed.) by John Henry Comstock

  1. genefish reblogged this from scientificillustration
  2. ptolemyhypatia reblogged this from scientificillustration
  3. di-atom reblogged this from scientificillustration
  4. death-bird reblogged this from scientificillustration
  5. 57thstreetbooks reblogged this from shelvesandshelves
  6. kitty-rambles reblogged this from scientificillustration
  7. kahristan reblogged this from scientificillustration
  8. redmerccruisin reblogged this from scientificillustration
  9. sexyplexi reblogged this from scientificillustration
  10. sosungalittleclodofclay reblogged this from scientificillustration and added:
    This is also why I thoroughly enjoyed Eight Legged Freaks.
  11. shelvesandshelves reblogged this from scientificillustration
  12. purplebloodedmajesty reblogged this from scientificillustration
  13. allisonindia reblogged this from scientificillustration
  14. booklungs reblogged this from scientificillustration
  15. urlcake reblogged this from scientificillustration
  16. scientificillustration reblogged this from rhamphotheca
  17. gwenmcgregor reblogged this from rhamphotheca
  18. butternutbuttskins reblogged this from adorablespiders
  19. alexthestrange reblogged this from rhamphotheca