BRITISH PALEOZOIC PHYLLOCARIDA. 



TABLE OF THE KNOWN GENERA OF FOSSIL PHYLLOCARIDA. 



I.-CARAPACE, UNIVALVE. 



I. Flat oe slightly convex Shield. 

 1. Neither sutured nor ridged along the hack. Notched in front. 



Middle and Up- 

 per Silurian. 1 

 Triassic. 

 Devonian. 



A. Posterior border entire. 



1. Discinocaris, H. Woodward. 1866. j Eound Bhie id ; angular notch. (These are 



2. Aspidocaris, Eeuss. 1867. j possibly the same.) 



3. p Spathiocaris, Clarke. 1882. Angular notch.^i These shields differ in shape. 



— 4. ? Pholadocaris, H. W. 1882. Sinuous notch. I Some of them are pro- 



— 5. ? Lisgocaris, Clarke. 1882. Oblong notch. bably the Aptychi of Oonia- 



— 6. ? Ellipsocaris, H. W. 1882. Bounded notch. J tites. 



b. Posterior border slightly notched. 



— 1. ? Cardiocaris, H. W. 1882. Front notch oblong. 



c. Posterior border deeply notched. 



Lower Silurian. 1 1. ? Pterocaris, Barrande. 1882. Both notches angular. Test radiately marked. 

 Lower Silurian \ 2. Dipterocaris, Clarke. 1883. Both notches angular. Test ridged along the 

 and Devonian. J middle. 



Lower Silurian. 3. ? Crescentilla, Barrande. 1872. Both notches angular. Possibly a sutured 



form. 



Devonian and 

 Carboniferous. 

 Carboniferous. 



2. Ridged along the back. (Like Apus.) 



") 1. Diihyrocaris, Scouler. 1843. Bidged and sometimes prickly, -j /- These are 

 i (Araas. Scouler. 1835.^ > \ possibly the 



(Argas, Scouler. 1835.) 

 2. Bachura, Scudder. 1878. (Only telson known.) 



> -j possibly the 

 J t same. 



3. Sutured along the back. Notched in front. 



e „.? n . P "I 1. Aptychopsis, Barrande (and H. W.). 1872. Angular notch. 



per Silurian. J r * r 



Lower Silurian. 2. Peltocaris, Salter. 1863. Eounded notch. 



— 3. Pinnocaris, B. E. Jun. 1878. Slight notch. Strise concentric far back. 



II. Folded Shield, bent along the back (like Nebalia), so as to foem an over- 

 arching Carapace, or a pair op attached Valves. 



Lingula-flags. 1. Hymenocaris, Salter. 1853. Smooth. 



Lower Silurian. 2. ? ' Cytheropsis testis' Barrande. 1872. Not well known. 



Uppermost Devo- -\ 



nian or Lowest > 3. Protocaris, Baily. 1872. Not well known. 



Carboniferous. ) 



1 In the old or Murchisonian sense. 



