mm. 



mm. 



mm. 



11-5 



11-0 



9-0 



9-0 



8-0 



7-0 



7-0 



6-5 



6-0 



no 



10-0 



8-0 



16-0 



14-5 



12-0 



9-0 



8-0 



7-0 



6-0 



o-2o 



50 



F. R. Cowper Reed — A New Carboniferous Trilobite. 243 



The actual surface of the pygidiura is not preserved in its entirety 

 in any of our specimens, but from isolated fragments of the shell 

 attached to the casts the above features can be made out. A fine 

 punctation is also noticeable on the surface with a hand-lens. The 

 under surface of the pygidium is furnished with a broad infolded 

 marginal portion ornamented with concentric striae. 



Hypostome elongate, obtusely pointed posteriorly ; central portion 

 convex, swollen, with subparallel sides ; anterior portion most 

 elevated, ornamented with several longitudinal lines, and provided 

 with a narrow border marked off by a faint groove. Alae subquadrate 

 rather than triangular in shape, marked with irregular wrinkles, not 

 separated from central portion of h3'postome by furrow. Eounded 

 narrow border surrounding posterior part of central portion behind 

 alfe, but marked off from it by distinct groove. Lateral angles 

 obtuse. 



Measurements of Six Specimens of Head -Shields and Pygidia. 



Length of head-shield 

 Length of glabella ... 

 Width of glabella at base .., 

 Length of pygidium 

 Width of pygidium 

 Length of axis 

 Width of axis at front end .. 



Affinities. — This new species, Phill. cracoensis, has wide affinities, 

 but does not appear to be closely allied to any of the British species. 

 The want of genal spines to the free cheeks recalls Phill. derbiensis 

 (Martin), but in almost every other detail the head-shield is different, 

 and the pygidium, moreover, bears no resemblance. 



With Phill. Colei (McCoy) it agrees in the general shape and 

 marginal characters of the pygidium, in possessing the same number 

 of segments on the pygidial axis, and in the faintness of the pleurae 

 on the lateral portions. But it differs in the shape and ornamentation 

 of the axis, and in the more strongly marked fulcrum and the 

 bifurcation of the ribs. The head-shield is completely different, 

 except in the relative size of the eyes ; and the hypostome is 

 narrower, has larger alee, and a more strongly developed posterior 

 border. 



The general shape of the glabella and course of the facial suture 

 are somewhat similar in Phill. gemmulifera (Phillips), but in all 

 other respects the differences are marked. The three pairs of 

 furrows on the glabella, in addition to the one marking off the basal 

 lobe, recall Phill. tnuicatula (Phillips). But the pygidium shows 

 little similarity. 



From Phill. Eichwaldi (Fischer) our species is in most respects 

 so completely different as to make any comparison needless. But 

 a hypostome doubtfully referred to Phill. Eichwaldi by Dr. Woodward^ 

 is not unlike that of Phill. cracoensis, except in its less elongate form, 

 less regularly convex axis, and triangular alee. 



1 Mon. Brit. Garb. Trilob., p. 22, pi. iv, fig. 4. 



