390 Pi'of. T. Rupert Jones and Dr. H. Woodward — 



illustrative of the genus, is C. Murchisoni as here defined. The 

 eye-spot, however, and the Mnge-joints are, in our opinion, super- 

 fluous and not substantiated. 



The synonyms of Ceratiocaris Murchisoni (Agassiz), 1839 : — 



1839. Onchus Murchisoni, Agassiz, in Silur. Syst. p. 607, pi. 4, fig. 10 (not figs. 



9 and 11) ; and Onclms, fig. 63?, and Iclithyodorulites, fig. 64. 

 1851. Leptocheles {Murchisoni), M'Coy. Synops. Brit. Palseoz. Foss. fasc. I, p.176. 



1853. Leptochcles Miirchisoni [Kga.s%.), M'Coy. Quart. Journ. Geol. Soc. vol. ix. 



p. 13 (omitting allusion to figs. 9 and II, Sil. Syst.). 



1854. Leptochcles Murchisoni (M'Coy), Murchison. Siluria, 1st ed. p. 236, pi. 19, 



figs. I, 2, and sp. fig. 3. 



1859. Leptocheles Mu7'chisoni [yi'Coy), Murchison. Siluria, 2nd ed. (3rd includ- 

 ing Sil. Syst.), pp. 263, 538, pi. 19, fig. I (2 and 3?). 



i860. Ceratiocaris Micrchisoni (M'Coy), Salter. Ann. Mag. Nat. Hist. ser. 3, 

 vol. V. p. 157. 



1866. Ceratiocaris Murchisoni, H. Woodward. Geol. Mag. Vol. III. p. 205, 



PI. IX. Figs. 8 and 9. 



1867. Leptocheles AJtcrchisoni{M.'Coy). Salter, in Siluria, 3rd ed. (4th including 



Sil. Syst.), p. 134, pi. 19, figs. I and 2. 

 1867. Leptocheles {Ceratiocaris) Murchisoni (M'Coy). Salter, in Siluria, 3rd (4th) 



ed. p. 237, pi. 19, figs. I (2, 3^). 

 1867. Ceratiocaris Murchisoiti (Agass.). Salter, in Siluria, 3rd (4th) ed. p. 516, 



pi. 19, figs. I and 2. 

 1867. Ceratiocaris Murchisoni (M'Coy), H. Woodw. Cat. Brit. Foss. Crust, p. 71. 

 1884. Ceratiocaris Pardoensis, LaTouche. Geol. Shropshire, p. 77) pl- I7> ^g- 5^3- 

 1884. Ceratiocaris leptodactylus. La Touche. Geology of Shropshire, p. 77j P^- ^7) 



fig. 566 (young C. Murchisoni), 



The synonyms of Ceratiocaris leptodactylus, M'Coy, founded 

 on certain slender tail-spines, which may have belonged to a varietal 

 form of C. Murchisoni (Agassiz) : — 

 1849. Pterygoius leptodactylus, M'Coy. Ann. Mag. Nat. Hist. ser. 2, vol. iv. 



P- 394- 

 1851. Pterygottis leptodactylus, M'Coy. Synops. Brit. Palceoz. Foss. fasc. i. p. 



176, pl. I E, figs. 7, ']a, ']b (not figs, ^c, 'jd). 

 1853. Leptocheles leptodactylus, M'Coy. Quart. Journ. Geol. Soc. vol. ix. p. 13. 

 1859. Leptocheles leptodactylus (M'Coy), Murch. Siluria, 2nd (3rd) ed. pp. 263, 538. 

 i860. Ceratiocaris leptodactylus (M'Coy), Salt. Ann. Mag. Nat. Hist. ser. 3, 



vol. V. p. 157. 

 1867. Leptocheles {Ce7'atiocaris) leptodactylus (M'Coy). Salter, in Siluria, 4th ed. 



(including Sil. Syst.), p. 237. 

 1867, Ceratiocaris leptodactylus (M'Coy). Salter, in Siluria, 4th ed. (including 



Sil. Syst.), p. 516. 

 1873. Ceratiocaris leptodactylus, Salter. Catal. Camb. Sil. Foss. p. 164. 



Taking M. Salter's description of the carapace of leptodactylus and 

 the appendages of Murchisoni as really both belonging to the latter, 

 and the more slender caudal spines (leptodactylus of M'Coy) as 

 belonging to a variety of the latter, we have looked for the two- 

 inch oblong carapace which Mr. Salter thought he had found for 

 Murchisoni (Ann. Mag. Nat. Hist. I.e.), but we have not met with it 

 at Ludlow, as led to expect by his remarks ; nor is it in the Museum 

 of Practical Geology, to which also he refers us. Indeed, we cannot 

 help thinking that some confusion of the specimens is hereby 

 indicated. 



The carapace of C. Murchisoni (as defined by us) is pyriform, or 

 acutely subovate, deep behind, narrow in front ; gently convex on 



