GRAPTOLITES OF NET/ YORK, PART 2 31? 



24 to 28 thecae in 25 mm, while Carruthers's and also Lapworth's figures 

 show but 20 to 22." 



We have not been able to find any specimens in the Stockport collec- 

 tion fitting in to the description of 1). elegans lately given by Miles and 

 Wood nor has Lapworth cited the species in his manuscript report on the 

 Stockport fauna ; or recognized it in the Normanskill shales of Canada. 

 Since moreover D. elegans is in Europe bound to a younger horizon 

 (zone of Pleurograptus linearis of the Hartfell shales) we believe that some 

 other slender Dicellograptus has been mistaken for this species ; and we are 

 probably near the truth in considering D . divaricatus var. b i c u r- 

 vatus as that form ; for this has the proximal double curvature, cited by 

 the British monographers as eminently characteristic of 1). elegans and 

 also the number of thecae quoted by Gurley. The thecae of I) . elegans 

 have strongly curved free ventral walls and their apertural parts are mark- 

 edly introverted and slightly introtorted, while the variety of D. divari- 

 catus has almost straight ventral walls. 



"&* 



Dicellograptus smithi ' sp. nov. 



Plate ig, figures 3-6 



Description. Rhabdosome small (prevailing length of branches almost 

 13 mm, greatest length observed 22 mm), branches of nearly uniform width, 

 which is .6 mm ; first straight and subparallel or including between them a 

 very small axillary angle for about 2 mm, then diverging abruptly so as 

 to include an angle of 60" and becoming concave, thereby converging dis- 

 tally and probably crossing finally. Sicular extremity round, furnished with 

 small virgella and lateral spines. Sicula very inconspicuous, apparently 

 not more than .6 mm long. Thecae numbering 12 to 14 in 10 mm, alter- 

 nately arranged on the inside and outside of the branches ; the first six to 

 seven of either side furnished with small spines, 1.4 mm long; overlapping 



1 Named after Prof. Eugene A. Smith, State Geologist of Alabama, who has most liber- 

 ally placed at my disposal the graptolites from the Trenton shales of Alabama and the 

 data on their horizon. 



