. Beginners' Zoology . 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 w
. Beginners' Zoology . 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).. FISHES ^15
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