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NEW YORK STATE MUSEUM 



specimens) consist of a central or longitudinal axis which is hollow 

 and jointed, and of whorls of lateral branches of pinnules, appar- 

 ently four, possibly five in number, radiating from the central axis 

 and forming a cylindrical body in the aggregate. The pinnules of 

 the whorls are composed of three elements each ; a first joint which 

 diverges from the central axis gives origin to two secondary joints, 

 while each of these supports two still smaller joints or pinnulae." 1 

 We insert here three of the original accurate figures by the 

 author of the genus [text fig. 1-3] and add a camera drawing of one 



] 



Primicorallina trentonensis Whitfield 

 Fig. 1 Slab with specimens. Nat. size 

 Fig. 2 Type, x 4 



FlG. 3 Transverse section. (Copies from Whitfield) 



of the type specimens [see pi. I, fig. i], to bring out a few charac- 

 ters not noted in the original description. 



^he following is the original description of the genotype: "Fronds of 

 small size, represented by cylindrical tufts of greater or less length, and of 

 from one sixth to one fourth of an inch in diameter. Axis of the frond 

 irregularly cylindrical and jointed; the joints count about 30 to the inch and 

 are nearly twice as long as thick. Pinnules four, or perhaps five, from each 

 joint of the axis, composed of cylindrical, oval or clavate joints; those 

 originating on the axis are of nearly an equal length with the axial 

 joints, and each supports two others on the outer end of very nearly or 

 somewhat shorter length, but of less thickness; these again each support 

 two others which are short oval in outline and of not more than half the 

 length of the others. Bifurcations of the pinnules diverging at an angle of 

 about 30 to 35 degrees to each other.'' 



