EMMELEZOE ELLIPTIC A. 69 



1859. Ceeatiocaeis eilipticus, Salter. In Siluria, 2nd (3rd) edit., p. 538. 



1860. — — — Ann. M. N. H., ser. 3, vol. v, p. 1.57. 

 1867. — — _ In Siluria, 3rd {4th) edit., p. 516. 

 1873, — — — Catal. Camb. Sil. Foss., p. 178. 

 1S77. — — H. Woodward. Catal. Brit. Pobs. Crust., p. 71. 



1885. — ? ELLiPTiCA, T. R. J. ^- H. W. Third Eeport Foss. Phyll., 



p. 352 ; Geol. Mag., 1885, 

 p. 466. 



1886. Ejimelezoe — — fourth Eeport, p. 232; Geol. 



Mag., 1886, pp. 459, 460. 



This interesting species, one of the first two established, is represented in the 

 Cambridge Museum by specimen 5/15 (the same as M'Coy's fig. 8 reversed). The 

 carapace is elongate, sub-ovate or suboblong in outline, convex medially, with the 

 greatest convexity of surface and curvature of ventral margin "at about one-third 

 from the anterior end;" obliquely rounded in front; obliquely truncate at the 

 upper portion of the hinder end, which rounds off" from the ventral margin below, 

 and slopes up to the blunt postero-dorsal angle above. The back is straight ; 

 the lower margin neatly curved. The valve measures 32 mm. long and 13 mm. high. 

 There is a spot like a definite ocular tubercle in the anterior fourth and above the 

 median line of each valve, and this gives it a distant likeness to a guinea-pig's 

 profile. The spot is a small round tubercle, at about a sixth of the valve's length 

 from the front, and a sixth of the height from the back. The surface is neatly 

 marked with delicate, longitudinal, parallel lines, rather far apart. The figure of 

 the specimen h/15, published in 1851, is reversed, and drawn too angular behind. 

 It came from the Upper Ludlow sandstone of Benson Knot. 



In 1860 Mr. Salter thought that C. elUptica was only a badly preserved variety 

 of C. inornata (' A. M. N. H.' I. c), but in the ' Catal. Cambr. Sil. Foss.,' p. 175, he 

 recognised it as " quite distinct." 



As intimated in our ' Third Report,' pp. 352, 353, the presence of the ocular 

 tubercle has an important significance, showing that the animal must have had 

 the organ equivalent to the eye suflSciently developed to affect the external covering, 

 whether it was adapted for clear vision or not. It is not only a generic character 

 distinguishing them from Geratiocaris, but probably an important family distinction. 

 At all events the oculate carapaces have to be removed from Geratiocaris, and we 

 have proposed that M'Coy's G. elliptica should be referred to a new genus under 

 the name Emmelezoe.^ 



The above-described and three other specimens supply our only evidence 

 of an eye-spot in these Ceratiocaridoid Phyllopods.^ 



1 'Efi/ieXi'is, elegant ; ^wi), life (a termination common in some of M. Barrande's genera). 

 * The " ocular tubercles " mentioned in the footnote at p. 236, ' Siluria,' 3rd (4tb) edit., 1867, 

 are without doubt due to the presence of " teeth " within the valves. 



