. Annual report . ; d Growth stage in which the first theca buds extremely close to the apex of the sicula and furtherdichotomy has set in. Reverse view. x7; e Young rhabdosorne with relatively short or fragmentary view. x7;/Greater enlargement of first dichotomy. x21. Deep kill sible to obtain specimens as well spread out as the type species of Gonio-graptus has furnished. Description. Sicula long and narrow, needlelike, with an average lengthof mm, but only a maximal width of . 35 mm; in some instances pro-vided with a long, very tine nema []. First theca bud
. Annual report . ; d Growth stage in which the first theca buds extremely close to the apex of the sicula and furtherdichotomy has set in. Reverse view. x7; e Young rhabdosorne with relatively short or fragmentary view. x7;/Greater enlargement of first dichotomy. x21. Deep kill sible to obtain specimens as well spread out as the type species of Gonio-graptus has furnished. Description. Sicula long and narrow, needlelike, with an average lengthof mm, but only a maximal width of . 35 mm; in some instances pro-vided with a long, very tine nema []. First theca budding withinthe apical fourth of the sicula; this and the. second theca diverging at ;ipoint one fourth of the length of the sicula from the apical end in oppositedirections and at right angles with the sicula. These first thecae are tili-form (about 2 mm long), their free portions mostly straight, but oftencurved upward. The secondary thecae (forming the branches of the second GKArTOLITES OF NEW YORK, TAUT 1 02!). order), which equal the primary in length and width, diverge under angles of 120° to 150°; the four principal steins describe a zigzag line, the sections of Avhich form an angle of 150°. The undivided denticulate branches stand at nearly right angles to the general direction of the principal stems. The thecae of the branches are tubular, narrow, about 2 mm long, three times as long as wide, one fourth to one third of their length in contact, numbering 8 in 10 mm, their outer margins nearly straight or slightly concave, the apertural margin straight and at right angles to the axis of the theca, inclined 10° to the axis of the branch. Total number of branches 40 or more; their length at maturity 30 mm or more. Central disk not observed. Position and localities. Extremelycommon at the Deep kill in a layer of the horizon with D i d y m o g r a p t u sb i f i d u s , but already beginning in the preceding horizon. Remarks. This species is closely related to the precedi
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectscience, bookyear1902
