. Zoology : for students and general readers . Zoology. SHARKS AND RAYS. 4^1 '-,'â Among the more tibemiiit sharks is the hammer-headed iSjjJii/Dia zygmna (Linn.), which grows to the length of twelve feet, and is one of the most rapacious and formidable of the order. Of the rays and skates, the saw-fish approximates most to the sharks. Its snout is prolonged into u long, flat bonj' blade, armed on each side with large teeth. Pristis antiquorum Latham (Fig. 390), the common saw- fish, inhabits the Mediterranean Sea and the Gulf of Mexico ; it is vivipa- rous (Caton.) Pristis Perroteli lives in
. Zoology : for students and general readers . Zoology. SHARKS AND RAYS. 4^1 '-,'â Among the more tibemiiit sharks is the hammer-headed iSjjJii/Dia zygmna (Linn.), which grows to the length of twelve feet, and is one of the most rapacious and formidable of the order. Of the rays and skates, the saw-fish approximates most to the sharks. Its snout is prolonged into u long, flat bonj' blade, armed on each side with large teeth. Pristis antiquorum Latham (Fig. 390), the common saw- fish, inhabits the Mediterranean Sea and the Gulf of Mexico ; it is vivipa- rous (Caton.) Pristis Perroteli lives in the Senegal Kiver, while Carcharias gangeticus is foitnd sixty leagues from the sea. The genuine skates or rays have the body broad and flat, rhomboidal (ow- ing to the great extension of the thick pectoral fins). Portions of the ventral fins in the males are so elon- gated and modified as to foi-m inter- mittent and clasping organs. They swim close to the bottom, feeding upon shell-fish, crabs, etc., crushing them with their powerful flattened teeth. The spiracle is esp>ecially developed in the rays, while, as observed by Gar- man, in the majority of the sharks which swim in midwater or near the surface, the water enters the mouth and passes freely out of the gill-open- ings, but in the rays, which remain at the bottom, the purer sea-water enters seen from beiow, slââ ,- â 1 ,. 1 X J. J! moutli, nostrile, and lateral the spiracle from above to pass out ot teeth.âAfter owen. the gill-slits. The smallest and most common skate of our northeast- ern Atlantic coast is Raja erinacea Mitchell. It is one half of a metre (twenty inches) in length, and the males are smaller than the females. The largest species is the barn- door skate. Raja Icevis Mitchell, which is over a metre (forty-. 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 perf
Size: 1074px × 2327px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, booksubjectzoology, bookyear1879
