236 CRUSTACEANS. 



Phillipsia meramecansis Herrick, 1889 : Bui. Dennison Univ. , vol. Ill, p. 



28, pi. xi, fig. 3. 

 Phillipsia merainecansis Herrick, 18S9 : Bui. Dennison Univ., vol. IV, p. 



54, pi. i, fig, 6. 



Pygidium semi-elliptic, slightly wider than long, very con- 

 vex ; marginal flattening rather narrow. Median lobe some- 

 what narrower than, and elevated above, the lateral lobes; an- 

 terior end considerably curved, posterior obtusely pointed; 

 segments thirteen in number, quite convex centrally, becoming 

 flattened on the sides; the separating furrows rather deep. 

 Lateral lobes strongly curved downward. Surface strongly 

 granulose. 



Horizon and localitiesi — Lower Carboniferous, Keokuk 

 limestone : Saint Louis, Fenton ( Saint Louis county). 



Phillipsia portlockii Meek & Worthen. 



Plate xxxii, flg. 7. 



Phillipsia portlockii Meek & Worthen, 1865 : Proc. Acad. Nat. Sci., Phila. , 

 p 268. 



Phillipsia {Oriffithides) portlockii Mftpk & Worthen, 1873: Geol. Sur. Illi- 

 nois, vol. V, p. 525, pi. xix, figs. 6a-c. 



Entire outline sub-ovate. Cephalic shield sub-semicircular, 

 nearly twice as wide as long, moderately convex, rounded in 

 front and straight behind, with posterior lateral angle terminat- 

 ing in short-pointed, spine-like appendage extending back to 

 thoracic segment. Glabella ovate, tumid, contracted and de- 

 pressed behind, widest and most convex or ventricose ante- 

 riorly, where it is about one-third narrower than its length from 

 the neck segment to its rounded front, which is not margined 

 by a protecting rim ; very distinct from the cheeks in conse- 

 quence of its greater convexity ; posterior lateral lobes small, 

 much depressed, and insolated by the oblique lateral furrows 

 in the front, being so directed as to intersect the neck fuirow ; 

 immediately in front of these there are on each side faint 

 traces of a small, very obscurely defined lateral lobe; anterior 

 lobe ovate, ventricose, and comprising more than one-tenth of 

 the whole; neck furrow deep and broad; its continuation 

 across the posterior side of the cheek dislinct, straight, and 

 terminating at the lateral furrows of the cheeks ; neck seg- 

 ment prominent, twice the size of the thoracic segments, and 



