WAVERLY GROUP SPECIES. 319 



the dorsal is upward, its most prominent part being near the middle, 

 along which the inflected edge is directed upward and inward, while its 

 entire length, owing to the obliquity of the posterior end, is shorter than 

 the dorsal margin; posterior margin very deeply and somewhat obliquely 

 sinuous, thus causing the downward-curved, posterior-dorsal extremity 

 to project considerably farther backward than the end of the basal mar- 

 gin below the sinus; anterior end narrowed, with its margin rounded 

 up from below so as to connect with the dorsal nearly at a right angle 

 above. Surface smooth to the unassisted eye, but showing under a mag- 

 nifier very minute reticulated markings. 



Length about 2.75 inches; height, 1.25 inches. 



This species agrees most nearly, in size and form, with Ceratiocaris 

 {Colpocaris) sinuatus, Meek and Worthen, from the Lower Coal Measures 

 of Grundy county, Illinois, and was found by Prof. Bradley enveloped in 

 exactly the same way in concretions. It differs, however, specifically in 

 being proportionally narrower in its vertical diameter, with the most 

 prominent part of its basal margin more nearly central. It also differs 

 "in having its posterior dorsal extremity more produced and more pointed, 

 as well as more curved downward, while that of its lower margin is 

 proportionally shorter, owing to the obliquity of the deep sinus of the 

 posterior end of the valves. 



Associated with these fossils Prof. Bradley also found the caudal ap- 

 pendages (telson and stylets) probably of this species, judging from their 

 comparatively large size. One of these specimens has these appendages 

 1.35 to 1.40 inches in length, and about 0.10 inch in breadth, at the lar- 

 ger end, the telson being apparently slightly shorter than the stylets, 

 (see fig. 6d, of plate 18). 



The specific name was given in honor of Prof. Frank H. Bradley, of 

 Knoxville, Tennessee, to whom I am indebted for the use of the type 

 specimens. The large specimen represented by fig. 6a is considered the 

 type of the species. 



Locality and position: Base of the Waverly group, at Danville, Kentucky. Prof. 

 Bradley's collection. 



Ceratiocaris (Colpocaris) elytroides, Meek. 



Plate 18, figs. 5a, b, c. 



Ceratiocaris (Colpocaris) elytroides, Meek (1872), Proceed. Acad. Nat. Sci., Pbilad., 

 XXIV, 334. 



Carapace valves narrow-subelliptic, about twice and a half to three 

 times as long as high, and rather distinctly convex; anterior end nar- 

 rower than the other, and subangular or narrowly rounded above ; dorsal 



