File:Lectures on the comparative anatomy and physiology of the invertebrate animals - delivered at the Royal College of Surgeons (1855) (14783563012).jpg

Identifier: lecturesoncompar02owen (find matches)
Title: Lectures on the comparative anatomy and physiology of the invertebrate animals : delivered at the Royal College of Surgeons
Year: 1855 (1850s)
Authors: Owen, Richard, 1804-1892
Subjects: Invertebrates Anatomy, Comparative
Publisher: London : Longman, Brown, Green & Longmans
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
per extremity of the mandible ;they have also a kind of lip situated immediately beneath, andcovering the mandibles, notched into four divisions, and answeringto the two pairs of maxillae of the Crustacea ; whence the name fromthe Greek, signifying, feeding by jaws. The lulus, or Gally-worm (Jig. 140), is a tjpe of this order. The Chilopoda have themouth composed of two mandibles, with a small palp ; a quadrifidlip, also the homologue of the crustaceous maxillae confluent; twolabial palpi, hooked at the tip; and a second pair of jaws, or footjaws,—the obvious homotypes of feet, — terminated by a stronghook, moveable, and pierced beneath the extremity by a poison-duct. The Centipede (Scolopendra) is the type of this order ofMyriapods, which feed by feet. 348 LECTURE XVI. Every Insect has a distinct head (Jig. 140,141, a\ provided with onepair of antennae (c), and every true or Hexapod Insect has its trunkdivided into two regions, called thorax (d^J /,) and abdomen (ah). 140 ^^^ 141
Text Appearing After Image:
lulus. Locusta. The thorax is interposed between the head and the abdomen, andso far is analogous to that part in human anatomy; but it hasneither the same relation to the contained viscera nor to the locomo-tive extremities which characterises the thorax in the vertebrateanimals. To the Insects thorax are attached all the locomotivemembers; both the first pair, which may be compared with the pec-toral extremities of the vertebrate animal, and the last pair, whichare analogous to the pelvic members, as well as the middle pair, towhich there is no correlative in the vertebrate series. This centre ofthe locomotive powers is divided into three segments, which corre-spond with the three pairs of legs: the first segment is termed the pro-thorax (d\ the second the meso-thorax (/), and the thirdthe meta-thorax (%). Each of these segments has a dorsal and asternal piece : the dorsal half-rings are called respectively prono-tum, mesonotum, and * metanotum ; the ventral or sternal arcsbear the

Note About Images