. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. Melocrmux. as the annexed figure shows, from the right adjacent radius to the left abjacent interradius, and is theretbre turned further from the radial axis by one de- cimal space. The observation was made on twenty calyces, partly be- longing to M. hieroglyphiciiSj from Stolberg, and ])artly to undescribed tjppcr Devonian species fi'om Senseille, near Couvin, in Belgium. In seven- teen calyces the normal divi- sion appeared; in the other three it deviated in the same way—nam
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. Melocrmux. as the annexed figure shows, from the right adjacent radius to the left abjacent interradius, and is theretbre turned further from the radial axis by one de- cimal space. The observation was made on twenty calyces, partly be- longing to M. hieroglyphiciiSj from Stolberg, and ])artly to undescribed tjppcr Devonian species fi'om Senseille, near Couvin, in Belgium. In seven- teen calyces the normal divi- sion appeared; in the other three it deviated in the same way—namely, so that the dorsal axis coincided with the radial. If a dlcijcllc qwadripartite base were divided in accordance with the same axis as the mo- nocyclic base of Melocrimts, and therefore stood in the same re- lation to this as the base of the Taxocrinida3 to that of Platy- / \ ^^ criniis, the segments of the inferior basal circle would be placed as in the annexed figure. A base divided in this manner has not yet been observed, but it has to be taken into con- sideration in the examination of the structure of the genus Cupressocrin us. Cuj)ressocrim(S has perfectly regularly constructed radii, without intcrradial plates. The ventral covering is unknown ; but the internal framework, extended between the radii, which is peculiar to the genus, possesses an interradially placed aperture, indicating the position of the vertical aperture—by means of which we are enabled to regard the calyx as divided in accordance with a radial axis, and therefore also to discuss the question whether the quadriradiate division of the stem, which occurs in most species of the genus, stands in the same relations to the radial division of the calyx as the division of- the base in other genera. The dicyclically constituted base of Cupressocrinus consists of a regularly quinquepartite upper circle and an undivided central plate, which sometimes extends flatly beyond the end of the stem, sometimes is
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