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-lateral 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 pleurm evenly tapering, the latter at about one- 
third their width from the axis abruptly deflected 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; 
Body. Cephalon. Thorax. Pygidium. 
Length_ 13 mm. 4.5 mm. 7 mm. 1.5 mm. 
Width__ 8 mm. 8 mm. 7 mm. 3.5 mm. 
