CRUSTACEA. 141 



Glabella sub-pyriform, evenly convex, sometimes slightly elevated along 

 the axial line; bounded by a strong sulcus, which is shallowest near the 

 palpebral lobe. Basal lobes pyriform, conspicuous: baso-lateral furrows 

 strong; antero-Iateral impressions faint. Frontal area scarcely appressed 

 against the glabella, evenly convex and depressed near the margin which 

 is thickened and slightly reflexed. 



Eyes elevated, conspicuous. Palpebral lobes relatively small. 



Cheeks sloping more or less abruptly from the orbital area to the thickened 

 margin. 



Thorax elongate; axis and pleurte evenly tapering, the latter at about one- 

 third their width from the axis abruptly deilected to the lateral margins. 

 Segments fifteen, each one of which is sulcate upon the pleurae, the anterior 

 limb being inconspicuous and becoming obsolete by the development of the 

 beveled planes of articulation. 



Pygidium small; width greater than twice the length. 



Axis strongly arched and bearing three annulations with traces of a, fourth, 

 beyond this point becoming obsolete just within the posterior margin. 



Pleura with abrupt lateral slopes and showing two faint duplicate annula- 

 tions. Doublure narrow. 



Surface smooth, sometimes finely granulose or minutely papillose, and 

 rarely tuberculate. The occipital ring of the cephalon occasionally bears a 

 single short spine at its center. 



Hypostoma. A single imperfect example shows the hypostoma slightly dis- 

 placed from its normal position. This organ is sub-quadrate, with the 

 centrum evenly convex, and separated by a furrow from the flat marginal 

 area. Anterior margin straight (?) ; lateral margins slightly incurved, wid- 

 ening posteriorly, posterior margin emarginate. 



Dimensions. A representative individual affords the following measurement: 



B. uly. Cephalon. Thorax. Pygidiuin. 



Length 13 mm. 4.5 mm. 7 mm. 1.5 mm. 



Width 8 mm. 8 mm. 7 mm. 3.5 mm. 



