394 Frof. T. R. Jones and Dr. B. Woodward— 



Descriptions of New Genera and Species," in the " American Journ. 

 of Science," vol. xix. January, 1880. Mr. Whitfield has obligingly- 

 favoured us with an illustrative plate ^ of these fossils. His figures 

 4, 5, and 6 are reproduced in the annexed Plate, as Figs. 3, 5, and 

 4 respectively. 



These specimens occur " in small calcareous concretions in the 

 Erie Shales (Portage and Chemung), at Leroy, Lake County, Ohio." 

 In one of these nodules, when broken, were exposed the inside of 

 a carapace-valve (imperfect) and a set of abdominal segments with 

 telson (see annexed PL XIII. Fig. 3). The valve is similar to the 

 better specimen shown by Fig. 5, obtained from another of the 

 nodules. The collocation of the carapace- valve and caudal portion 

 in one nodule (Fig. 3) is necessarily of great value (and may be 

 accepted as conclusive evidence) in proving that these parts belonged 

 to one individual ; especially as Phyllopods of the Ceratiocaris type, 

 and others, have a bivalved carapace with analogous abdominal and 

 caudal appendages. The tail -piece in the nodule is enlarged in 

 Fig. 4 (fig. 6 of Mr. Whitfield's plate) ; and a carapace-valve 

 similar to that associated with it is shown by Fig. 5. Mr. Whitfield 

 has determined them as belonging to a new Phyllopodous genus of 

 the " Ceratiocaridge," namely Echinocaris, remarkable for the spines 

 on its abdominal segments and having a Leperditioid foi'm of valve. 

 This is the E. sublcdvis, Whitf. ; and he adds another nearly allied 

 form, from the same Devonian concretions, as E. pushdosa (Fig. G 

 in our Plate ; fig. 7 in Mr. Whitfield's). By the introduction of 

 the figure of an Aristozoe (A. Canadensis, Whitf., "from the Trenton 

 Limestone (?) near Ottawa") in the same plate (fig. 9), "for com- 

 parison," Ml'. Whitfield would show a difference rather than a like- 

 ness, as he considers M. Barrande's reference of this form to the 

 Ostracodes as correct (p. 33), and does not agree with Prof. Hall in 

 suggesting Aristozoe as a possible synonym for his new fossil (see 

 above). It seems to us, however, that Aristozoe, Orozoe, and Callizoe, 

 of Barrande, are close allies of the Ceratiocarid group (as intimated 

 in the Table at p. 462, Geol. Mag. October, 1883 ; and " Eeport 

 Brit. Assoc." for 1883), although as yet no tail-pieces have been 

 recorded as having been found in direct connection with them. 

 Among the Bohemian specimens in the British Museum, there is 

 one style or stylet lying close to an Aristozoe perlonga ; but there is 

 no clear evidence that the one belonged to the other. 



To return to Echinocaris : ' — Mr. Whitfield very properly refers 

 to Prof. Hall's Ceratiocaris armatus and G. punctatus (above men- 

 tioned) as being evidently of the same genus as his own Leperditioid 

 and spiny specimens ; and as Prof. Hall unites his two species, on 

 good evidence (see above), we have the three well-determined species : 



1. Echinocaris armata (Hall). 



2. siihlcBvis, Whitfield. 



3. pustulosa, Whitf. 



^ ^'Devonian Crustaceans,''^ prepared for the " Palseontology of Ohio," vol. iii. 



