Petromyzon, the Lamprey

Identifier: introductiontozo00dave Title: Introduction to zoology; a guide to the study of animals, for the use of secondary schools; Year: 1900 (1900s) Authors: Davenport, Charles Benedict, 1866-1944 Davenport, Gertrude Anna Crotty, 1866- Subjects: Zoology Publisher: New York, Macmillan company London, Macmillian and co., ltd. 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: FIG. 228. — Siphostomafuscum, the pipe-fish. Nat. size. Photo, by W. H. C. P. elongated snout, and usually a long, slender tail. Thebody is encased in bony plates, and the male is often pro-vided with a brood-pouch, in which the developing youngare carried. Besides the bony fishes, which we have just consideredin detail, there are various other classes of fish. Text Appearing After Image: FIG. 22l>. —Petromyzon, the lamprey. One-fourth nat. size. After Goode. The Cyclostomi, or lamprey eels, are the only parasiticvertebrates. In the adult stage they either live attached 246 ZOOLOGY to the outside of other fishes, sucking their blood, or else they may penetrate intothe body cavity. Theydo not bite, because theyhave no lower jaw, andare known as round-mouthed eels.1 Lam-preys are found in the seasand in the rivers of thetemperate zones. Theyoccur on our Easterncoast and ascend rivers ;others live in the lakes ofNew York, in the GreatLakes, and in the Missis-sippi valley. In Europethey are much esteemedas food. The Selachians includethe sharks and rays, allinhabitants of the sea.They may be distin-guished from the bonyfishes by the rough skin,beset with spines, and bythe cartilaginous skele-ton. We have a num-ber of sharks on ourNortheastern coast, ofwhich the dogfishes andthe sand-shark are the i Fig. 229. Note About Images Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.