October, 1913. New Trilobites — Slocom 67 



Calymene fayettensis sp. nov. Plate XVI, Figs. 8-9. 



Type specimen No. P 16755 Field Museum. 



Body strongly trilobate, subovate in outline, greatest breadth at the 

 genal angles, narrowing gradually to the anterior border of the pygi- 

 dium, thence abruptly to the posterior extremity of the pygidium. 

 Surface finely papillose with small rounded tubercles more or less 

 regularly distributed thereon. 



Cephalon sublunate in outline, anterior border arcuate, except 

 between the anterior limbs of the facial sutures, where it is somewhat 

 produced. Glabella moderately convex, not prominent anteriorly, 

 slightly elevated above the cheeks, well denned by the dorsal furrows, 

 broadest across the posterior lobes where the width nearly equals the 

 length, gradually narrowing towards the front, which is truncated; 

 frontal lobe quadrangular, occupying less than one-fourth the length of 

 the glabella; first lateral lobes small, hardly separated "from the frontal 

 lobes; second lateral lobes larger and nodelike; posterior lobes much 

 larger, forming a pair of conspicuous nodes at the base of the glabella. 

 The lateral furrows do not cross the glabella, first pair indistinct, trans- 

 verse; second pair well defined and bent backward; posterior pair 

 broader and deeper than second pair, curved backward so as to nearly, 

 but not quite, isolate the posterior lobes; occipital furrow arched forward 

 in the middle, somewhat deeper and narrower back of the posterior gla- 

 bella lobes, where it merges into the posterior cheek furrows; occipital 

 segment prominent, widest in the middle, gradually narrowing to the 

 dorsal furrows. Cheeks convex, with rounded lateral and sharp 

 posterior marginal borders, greatest elevation at the palpebral lobes; 

 marginal borders defined by shallow, concave furrows; free cheeks 

 subtriangular, about half the size of the fixed cheeks. Facial sutures 

 originate at the genal angles which they unequally bisect; from thence 

 they pass obliquely forward until opposite the posterior glabella furrow; 

 thence curve abruptly over the eye lobes to the anterior border, which 

 they cut almost in front of the eyes. A small free plate to which the 

 hypostoma is attached occupies the space between the anterior ex- 

 tremities of the sutures. Eyes small, lenses not preserved, situated well 

 forward, about opposite the second glabella furrows. 



Thorax composed of thirteen segments, length about three-fifths the 

 entire length of the test, strongly trilobed; segments arched forward on 

 the axis, each one bearing a pronounced rounded node on either side 

 just within the dorsal furrows, and a smaller, more pointed one on each 

 pleura, pointing forward, situated on the anterior margin at the crest of 

 the convexity, when the body is rolled up; on the posterior margin is a 

 notch or indentation into which the node from the next posterior seg- 



