. Beginners' Zoology . Fig. 212. — Skeleton of Perch. grasping ? Why are teeth on the tongue useful ? Watcha fish eating: does it chew its food ? Can a fish taste ?Test by placing bits of brown paper and food in a vesselor jar containing a live fish. Is the throat, or gullet, of thefish large or small ? The skeleton of a fish is simpler than the skeleton ofother backboned animals. Study Fig. 212 or_ a preparedskeleton. At first glance, the skeleton appears to havetwo vertebral columns. Why ? What bones does the fishhave that correspond to bones in the human skeleton ?Are the projections (proce
. Beginners' Zoology . Fig. 212. — Skeleton of Perch. grasping ? Why are teeth on the tongue useful ? Watcha fish eating: does it chew its food ? Can a fish taste ?Test by placing bits of brown paper and food in a vesselor jar containing a live fish. Is the throat, or gullet, of thefish large or small ? The skeleton of a fish is simpler than the skeleton ofother backboned animals. Study Fig. 212 or_ a preparedskeleton. At first glance, the skeleton appears to havetwo vertebral columns. Why ? What bones does the fishhave that correspond to bones in the human skeleton ?Are the projections (processes) from the vertebrae long orshort ? The ribs are attached to the vertebrae of the trunk,the last rib being above the vent. The tail begins at the 114 BEGINNERS ZOOLOGY vent. Are there more tail vertebrae or trunk vertebras?Are there any neck (cervical) vertebrae { in front ofthose that bear ribs)? The first few ribs (how many ?) areattached to the central body of the vertebrae. The re-. FiG. 213. maining ribs are loosely attached to processes on thevertebrae. The ribs of bony fishes are not homologouswith the ribs of the higher vertebrates. In most fishesthere are bones called intermuscular bones attached to thefirst ribs (how many in the perch ?) which are possibly homol-ogous to true ribs; that is, true ribs in the higher verte-brates may have been developed from such beginnings. Which, if any, of the Jifi skeletons (Fig. 214) are notattached to the general skeleton? Which fin is composedchiefly of tapering, pointed rays ? Which fins consist of rays which sub-divide and widentoward the end ?Which kind are stiff, and which areFig. 214. — Soft-rayed and Spiny-rayed Fins. „ .-, ?, ^ ,.,r, . , flexible? Which ofthe fin rays are segmented, or in two portions ? The outersegment is called the radial, the inner the basal segments are longer ? There is one basal segmentthat lacks a radial segment. Find it (Fig. 212).
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