A treatise on zoology . me of the genera have been allied by naturalists. Tothese characters may be added the presence of diplopores, whichare still to be found in the most primitive genus. Fnmi the By F. A. liatlin, ^ The term ainbulucrum has been hxwely used in the IMustoidoii for thethecal elfinents coinu!cte<l with tlie food-Kroove. INouduinbnhicnim is morecorrect and more cumbrous. The rehitious of the true ambulacral system are doubtful. THE BLASTOIDEA 79 Edrioasteroidea they iiro separated by the presence of brachioles andabsence of ambuhicral i)orcs. Their line of evolution, th
A treatise on zoology . me of the genera have been allied by naturalists. Tothese characters may be added the presence of diplopores, whichare still to be found in the most primitive genus. Fnmi the By F. A. liatlin, ^ The term ainbulucrum has been hxwely used in the IMustoidoii for thethecal elfinents coinu!cte<l with tlie food-Kroove. INouduinbnhicnim is morecorrect and more cumbrous. The rehitious of the true ambulacral system are doubtful. THE BLASTOIDEA 79 Edrioasteroidea they iiro separated by the presence of brachioles andabsence of ambuhicral i)orcs. Their line of evolution, thou<^h insome respects parallel to those of the Callocystinae and Edrioas-teroidea, was indei)cn(lently derived through the Diploporita fromthe primitive Amphoridea. Within the class itself may l)e traced the increase of penta-merism, combined with a lessening in numljer of the thecal platesuntil a very definite arrangement is reached. At the same time,there is a concentration of semi-porous structures into the inter-.
Size: 1542px × 1621px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublishe, booksubjectzoology
