CRUSTACEA. 47 



Observations. It has been suggested ly Professor Emanuel Kayser (Fauna d. 

 aeltst. Devon-Ablagerungen d. Harzes (he. tit.), p. 33), thai all the pygidia of 



Dalmanites Boothi represented in the Illustrations of Devonian Fossils {lor. tit.), 

 do not belong to the same species, and he has consequently divided them in 

 the following manner: Fig. 10 (pi. xvi), = Cryphoms stcllifer, Burmeister; figs. 

 8, 11, 14,= CryphcRus laciniatus, C. F. Roemer; tigs. 3, 6, 9, = Cryplueus Calli- 

 teles (Boothii), Green. Our observations do not sustain this sub-division. The 

 type of C. stellifer, Burmeister (Organiz. der Trilobiten, pi. iv. fig. 8), shows a 

 terminal spine upon the pygidium, exceeding in length any of the marginal 

 spines: the same is true of C. Calliteles? Kayser (loc. tit., pi. iii, fig. 10). This, 

 however, is a feature which has not been observed in any specimen of the New 

 York species. C. laciniatus, C. F. Rcemer, bears a distinctly triangular caudal 

 shield and a very broad terminal lobe, while the C. laciniatus of the Sandbergers 

 (Versteinerungen d. Rhein. Schicht. Syst., pi. i, fig. 5c), referred by Kayser to 

 C. stellifer, Burmeister, differs in this feature, and if correctly figured, might 

 with propriety be regarded as identical with C. Boothi, var. Calliteles. 



Distribution. Upper Helderberg group ] Dalmanites (Cryphcms) Boothi. The 

 pygidia of this species have been observed in the limestone lying beneath the 

 Marcellus shales at the Indian Reservation, four miles south of Buffalo, Erie 

 county, associated with Chonetes lineata, Yanux., and Ch. laticosta, Hall. Hamil- 

 ton group. Marcellus shales: In the limestone near the top of these shales, on 

 Flint Creek, Ontario county ; LeRoy and Stafford, Genesee county. Hamilton 

 shales: Rarely in the sandy shales of the eastern and central counties, at Bear's 

 Gulf, near Summit, Schoharie county ; East Worcester, and elsewhere, Otsego 

 county; Cazenovia and Madison, Madison county; Pratt's Falls and Delphi, 

 Onondaga county; abundant in many localities in the western counties; on the 

 shores of Seneca and Cayuga Lakes; in the shales above the Encrinal limestone 

 at Menteth's and Tichenor's Points, on Canandaigua Lake, and in the towns of 

 Hopewell, Gorham, Canandaigua and East Bloomfield, Ontario county; Pavi- 

 lion and Darien, Genesee county ; Jaycox's Run, near Geneseo, and Moscow, 

 Livingston county ; Eighteen-mile Creek and Hamburgh, Erie county. Also 

 from Thunder Bay Run, Michigan. Dalmanites (Cryphaus) Boothi, var. Calliteles: 



