. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. 118 THREE CRUISES OF THE " BLAKE. mens the cirri of which had become attached to adjoining' stems. It is possible that they may live gregariously, more or less united either by the twisting of the stems or the grappling of the cirri, and be only loosely attached to the ooze on which they live, or anchored more securely by the terminal whorl to some project- ing piece of rock or gorgonia stem. Crinoids both stalked and free live in colonies. Comatulse are most abundant in certain local- ities. Antedon Sar
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. 118 THREE CRUISES OF THE " BLAKE. mens the cirri of which had become attached to adjoining' stems. It is possible that they may live gregariously, more or less united either by the twisting of the stems or the grappling of the cirri, and be only loosely attached to the ooze on which they live, or anchored more securely by the terminal whorl to some project- ing piece of rock or gorgonia stem. Crinoids both stalked and free live in colonies. Comatulse are most abundant in certain local- ities. Antedon Sarsii was brought up in thousands by the " ; The U. S. Fish Commission and the " Challenger " have had a sim- ilar experience with different spe- cies of Comatulse. On one occa- sion, off Sand Key, we must have passed over a field of Rhizocrinus with the dredge, judging from the number of stems and heads of all sizes it contained. The oldest species known, Pentacrinus asterius (Fig. 405), is marked by its greatly mul- tiplied large and strong arms, while in P. decorus (Fig. 407) the num- ber is greatly reduced. We know but little of the young of Pentacri- nus. The youngest spec im ens dredged by the " Blake," and fig- ured by Carpenter (Fig. 408), show the great relative height of the stem joint as a characteristic feature of young specimens. The stems of Pentacrinus asterius and P. decorus are longer than those of the other species of the genus. P. Mulleri (Fig. 409) was dis- covered by Oersted, and in 1865 Dr. Liitken gave a detailed account of the West Indian Pentacrinidse; the many speci- mens of Pentacrinus dredged by the " Blake " were originally identified with it, but, as has been clearly shown by Carpenter, they all belong to P. decorus. Both P. Mulleri and Fig'. 408. — Pentacrinus decorus. (Carpenter.). Please note that these images are extracted from scanned page images that may have been digitally enhanced for readab
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