. Annual report . tinguishing characters. Description. Rhabdosome consisting of four elongate, semiellipticbranches, which have nearly ecpial width throughout or are a little widernear the sicular end. Thecae in contact throughout, numbering 11 to 13in lo mm, being very little curved and directed at a uniform angleobliquely upward, the inclination increasing somewhat toward the anti-sieular end. The thecae of the sicular end are in their proximalportion nearly horizontal and slightly bent down in their distalportion. The apertures of this species are very characteristic, the mucronateextension
. Annual report . tinguishing characters. Description. Rhabdosome consisting of four elongate, semiellipticbranches, which have nearly ecpial width throughout or are a little widernear the sicular end. Thecae in contact throughout, numbering 11 to 13in lo mm, being very little curved and directed at a uniform angleobliquely upward, the inclination increasing somewhat toward the anti-sieular end. The thecae of the sicular end are in their proximalportion nearly horizontal and slightly bent down in their distalportion. The apertures of this species are very characteristic, the mucronateextension of the lower part of the same being much longer than that ofthe upper, so that the margin of the aperture appears to recede in anupward direction. This extension attains a length of one and one half timesthe width of the thecae. Position and localities. This species occurs in all three horizons of theDeep kill section. It finds its typical development in the last horizon (with GRAPTOLITES OF NEW STORK, PART 1 713. <v P h y 11 o g r a p t u s angusti-lolius Hall. Middle portion of rhab-dosome enlarged. Shows the shape ofthe apertures in compressed state, andthe central canal. Deep kill. x4. 8 Diplograptus den tat us), specially in the lower part of the same,exposed in the Ashhill quarry at Mt Moreno, Hudson, where it is verycommon. Hairs types came from the shales of Point Lexis; but, as noassociated forms are mentioned, the horizon is not determinable from his , however, cites it from several localities near Point Levis and Quebec inassociation with species of the zones of Didy mogr apt us bifid usand of Tetragraptus. It can be thus inferredthat, in the Quebec region as well as at the Deepkill, it ranges through several zones. A similarrange of the species has been observed by Ellesand Wood in Great Britain. Also in Sweden(Scania) it appears to be a form of the Tetra-graptus horizon as well as of the Phyllograptuscf. typus zone. Brogger found it associated wi
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectscience, bookyear1902
