258 NEW YORK STATE MUSEUM 



This form has all the appearance of belonging to the curious genus 

 Azygograptus, Two specimens occur in the collection. One lacks the 

 proximal part ; in the other there is evidence of the unilateral nature of the 

 polypary and of the presence of the sicula. Further research may show- 

 that it belongs to the bilateral genus Leptograptus, but in any case it is a 

 new and undescribed form of the family. If it actually belongs to Azygo- 

 graptus, this is the first specimen of the genus on the American side of the 

 Atlantic, and there is special appropriateness in its dedication to Mr Wal- 

 cott, whose recent researches have done so much to elucidate the sequence 

 and fossils of the strata in which it occurs. 



Dr Gurley has not published any figures with the original description, 

 nor have we been able to find the two type specimens mentioned in the 

 description. Professor Lapworth has, however, furnished a camera drawing 

 of the type with his manuscript which we take the liberty of reproducing 

 here. We have not found any other specimens which could be identified 

 with this species. 



Azygograptus ? simplex sp. nov. 



Plate 14, figure 10 



The Normanskill shale has furnished in various outcrops, notably at 

 Mt Moreno, at Glenmont near Albany and at the power house near Lan- 

 singburg, a considerable number of elongate triangular bodies which have 

 the form and structure of siculae but are of such size that the}- can not be 

 referred to any of the associated graptolites. Moreover, they frequently 

 occur alone in the shale and they have not been observed to produce more 

 than one theca. With our present knowledge it is therefore to be inferred 

 that they either represent the sicula of a gigantic form which at present is 

 unknown, or that they belong to an independent species of a group that in 

 the process of reduction has gone so far beyond Azygograptus that only 

 one theca is left of the branch and the whole rhabdosome, as a rule, consists 

 only of an overgrown, so to say, sicula. We incline to the latter view on 

 account of the failure of finding more advanced growth stages in even very 

 large collections. 



We have at one time [N. Y. State Mus. Bui. 42, p.52off] identified these 

 interesting organisms provisionally with Dawsonia campanulata 



