Bulletin - United States National Museum . ^ arched, withan apical mucro. The roof is rounded, micrum xs, with ,, 1 • ; ,1 .1 . DETAIL VIEW OF ROSTRUM. /,. passing directly into the narrow sides; it is transversely marked with deepU^ arcuate growth-lines. The apexreaches to the upper third of the length of the carinal margin of thetergum. The base is rounded. The upper latus is trapezoidal with straight margins, the carinalmargin nearly half as long as the scutal, the tergal and basal marginsabout equal. The apex is terminal at the scuto-tergal angle. The well-developed ros
Bulletin - United States National Museum . ^ arched, withan apical mucro. The roof is rounded, micrum xs, with ,, 1 • ; ,1 .1 . DETAIL VIEW OF ROSTRUM. /,. passing directly into the narrow sides; it is transversely marked with deepU^ arcuate growth-lines. The apexreaches to the upper third of the length of the carinal margin of thetergum. The base is rounded. The upper latus is trapezoidal with straight margins, the carinalmargin nearly half as long as the scutal, the tergal and basal marginsabout equal. The apex is terminal at the scuto-tergal angle. The well-developed rostrum forms a band about one-fifth as wide aslong, and slightly narrower above than at the base. It extends thewhole length of the adjacent latera. The rostral latus is triangular, with the basal angle of the triangletruncated. The three sides are about equal, the two upper anglesalso equal. The inframedian latus is narrow, triangular, its height equal to that ofthe rostral latus, and about double the basal width. The umbo is 58 BULLETIN 00, UNITED STATES NATIONAL MUSEUM. The carinal latus is irregularly pentagonal, widest above the middle,exceeding in area the upper and the rostral latera. The upper lateraland carinal facets are equal and straight, the lower lateral longer,straight, and the subcarinal margin still longer, concave. The basalmargin is shortest. The uml)o projects angularly be3ond the dorsal aspect the two carinal latera are seen to meet below the carinain a straight suture as far up as their umbones. The peduncle is very short, covered with large imbricating scalesin five rows of four scales each. Length of the capitulum 5, breadth mm. Length of thepeduncle L8 mm. Length of the carina mm. This minute form is notable for the length of the plates of thelower whorl, especiall}^ of the carinal latera, and for the shortness ofthe carina. It is closely related to S. l>re)uca7H7iatam Hoek, but inthat antipodal species the whole capitulum
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Keywords: ., bookauthorun, bookcentury1800, bookdecade1870, booksubjectscience
