238 



NEW YORK STATE MUSEUM 



at Lansingburg, in immense numbers and in association with D i p 1. 

 amplexicaulis var. pertenuis and Climacogr. modestus; in 

 Rusher's quarry in south Troy in association with Dipl. amplexi- 

 caulis; and at Bakers Falls (Sandy Hill, Washington co. ), in association 

 with D i p 1 o g r. amplexicaulis and Trocholites ammonius, 



C. gracilis is recorded by Lapworth only from the Hartfell shales 

 of Scotland. 



Remarks. The original description of C. gracilis reads: 



Polypary from about 5/8 to ^ inch in length, and 

 about J / S o of an inch in average breadth, gradually 

 expanding from the proximal to the distal end, where 

 there is a slight bulbous expansion terminating in short 

 acutely pointed teeth. 



Commencing with two slender radicular processes 

 which lie so close together that they are scarce!}' indi- 

 vidually perceptible, the polypary, here not y r0 o of an 

 A inch in breadth, gradually enlarges until a breadth of 



nearly Y i0 of an inch is attained. Up to this point the 

 margins of the polypary are almost perfectly straight, 

 but here there is a slight enlargement, which in C. 

 calicularis ( Nich.), has been described as a " cuplike 

 hydrotheca." This portion of the polypary is about 

 i j' 20 of an inch in length, and scarcely l / 20 in breadth at 

 ._ 35 corynoides itswidest part. It is convex in form, and terminates 

 copies of Ho^kS's ori|'inai clistally in about five acutely pointed teeth, which at 



figures. Fie. 134 A specimen r • 1 , . £ .1 r ^1 ' 



which shows the sicuu and the first sight appear to tomi the greater part of this so 



diverging apertures of the three 11 i 1 i , i t> , i • l i i 



thecal Fig. 135 Distal ex- called hydrotheca. but tins appearance is caused by 



tremity of another rhabdosome. i r\ 1 11* ^1 * 1 i" ^1 



The last two figures are enlarged several nbers, somewhat resembling the virgula ot the 



typical graptolites, which traverse the polypary through- 

 out its length, and form the extreme distal termination of each of these 

 segments, which are really connected together to within a short distance 

 of their apices. These fibers, whatever their nature may be, apparently 

 form a framework which supports the less rigid and more membranous 

 portion of the polypary, as the frame of an umbrella supports its cover. 



As in C. calicularis, also here our specimens fail to attain the 

 maximal length of the Scottish type, but full)- agree in the other dimensions 

 given. Our material tallies exactly with the figure given by Lapworth in 

 the Catalogue of the Western Scottish Fossils. The fibers mentioned in 



