PHYLLOCARIDA. 

 CERATIOCARID^E. 



CERATIOCARIS, McCoy. 1849. 

 Ceratiocaris longicauda. 



PLATE XXXI, FIG I. 



Ceratiocaris longieaudus, Hall. Sixteenth Rept. N. Y. State Cab. Nat. Hist., p. 7:i. pi. i. t'n. r . 7 (not figs. 4, 



5 and 6). 1863. 

 Ceratiocaris longieaudus, Packard. Twelfth Ann. Rept. D. S. JSeol. Suit., Monog. N. Amer. Phyllopod 



Crust, p. 450. IS83. 

 Ceratiocaris (.') lonr/icaudus, Jones and Woodward. Notes on Phyllopod. Crust., referable to the genus Echi- 



QOcavis, etc.. Gfeol. Mag., Dec. iii. vol. i. No. 9, p. 1. 1S84. 

 Ceratiocaris longieaudus, Etheridge, Woodward and Jones. Third Rept. Com. on Fossil Phyllopoda 



of the Palaeozoic Rocks, p. 35. 1885. 

 Not Ceratiocaris longieaudus, Clarke. Bull. O. S. Geol. Surv., No. 16, Hig-her Devonian Faunas of Ontario 



county, N. Y.. p. 20. 1885. 



The original of this species is a very tenuous impression of the last two 

 abdominal somites and two caudal spines, one of which may be the telson. Of 

 the somites the penultimate is broad and suit-quadrate, slightly longer than wide; 

 the ultimate much narrower and more elongate, being twice as long as wide. 

 The caudal plate is not distinguishable ; of the two spines, one which is un- 

 broken, is as long as the two somites. The entire length of the fragment is 

 26 mm. ; the first of the somites measures •"> mm. in length and 4.5 mm. in 

 width; the second 7.5 mm. in length and 3.7 mm. in width, and the longer of 

 the caudal spines has a length of 12.5 mm. The specimen has been so flat- 

 tened in the shale that superficial markings are not discernible. But a single 

 example of this species has been observed, and this is from the black slaty shale 



