420 NEW YORK STATE MUSEUM 



Climacograptus putillus ( Hall) mut. eximius now 



Plate 28, figure 16 



Cf. Diplograptus putillus Lapworth. Roy. Soc. Can. Proc. & Trans. 



1886. 4:170, i78ff' 

 Diplograptus aff. putillus Ruedemann. N. Y. State Mus. Bui. 42. 



1901. p. 541 



The typical putillus has in the shales of New York State been 

 found only in the Utica and Lorraine horizons. In the shale near the 

 power house at Lansingburg, the writer has found a mutation of C . 

 putillus occurring in great numbers associated with Normanskill forms ; 



and also the Normanskill shale 

 near Glenmont, Albany co., has 

 afforded a few specimens. This 

 mutation is distinctly narrower (its 

 width only .7-1 mm), of somewhat 

 greater length (10 mm, average 8 

 mm) and has especially a closer 

 arrangement of the thecae (16-18 

 thecae in 10 mm or 40-45 in 1 

 inch). The form of the thecae is 



382 383 



Fig. 378-84 Climacograptus putillus mut. eximius 

 nov. Fig. 378-82 Different aspects of typical specimens from ,*,,„ ~4-1-, r „„ ' ,, /"" f- ' 1 T 



Lansingburg. (x 5). Fig. 383 Specimen from Glenmont, N. Y. cXaCU) aS 1 11 W . p U I 1 1 I U S \Ml 

 (x 5). Fig. 384 Sicular end of rhabdosome from Lansingburg, 

 enlarged x 6 t ext fig. 380, 381]. While IHOSt 



specimens possess only a short virgella at the sicular extremity, a few are 

 distinctly furnished with short lateral spines [text fig. 378 ]. 



Lapworth has doubtfully referred to C . putillus specimens observed 

 by him in collections of the Coenograptus-gracilis zone (Normanskill shale) 

 on the south side of the St Lawrence (Tartigo river, Griffin Cove) and 

 from Cape Rouge and designated that species as a long range form, which 

 passes through that zone and into the next British one above. There is 

 little doubt that the Canadian specimens of the Dicellograptus /one to 

 which Lapworth refers belong also to this mutation. 



