. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. Note on Botryocrinus pinnulatus. 193 Arms are preserved to a length of 85 millim.; they probably reached at least 90 millirn. Thus they were more than ten times the height of the cup, and this suggests that the arms of the type specimen were longer than was thought. The arms agree in essential structure with the type specimen, but throw some light on the peculia- rities of branching described for that specimen. The axial canal exists as a mere tongue from the ventral groove in
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. Note on Botryocrinus pinnulatus. 193 Arms are preserved to a length of 85 millim.; they probably reached at least 90 millirn. Thus they were more than ten times the height of the cup, and this suggests that the arms of the type specimen were longer than was thought. The arms agree in essential structure with the type specimen, but throw some light on the peculia- rities of branching described for that specimen. The axial canal exists as a mere tongue from the ventral groove in all the arm- ossicles, in which respect this specimen appears to differ from the type, if the appearances pre- sented by that specimen were correctly interpreted. The cover- ing-plates are numerous and minute, and appear to be slightly irregular in arrangement. I Br, in the two arms seen, number 4 and 7, and average 3 millim. in both height and width. II Br2 is axillary and gives off on its outer side a long armlet. The widths of the main arm- branch and the armlet, at the point where the latter originates, are respectively 2*5 and 1*5 millim.; in other words, the arm- the width of the main The length of the armlet appears almost to equal that of the main branch, and it appears to have borne smaller branches or pinnules. (Fig. 3.) The structure just described suggests that some at least of the secondary arm-branches in the type specimen are not ab- let is |- Fig. Mr lal all, but that the Part of Anterior Arm of Madeley's specimen of Botryocrinus pinnulatus ; showing' the secondary branching, and indications of the pinnules; very slightly diagrammatized. (x2diam.) after species does normally branch, in some or all of its arms, on HBr2. In this respect, then, B. pinnulatus would resemble those American species of Barycrinus to which allusion was made (loc. cit. p. 405), differing from them, however, inthe facts that there may be four arms to a ray, not merely three,
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