756 



ARTHROPODA 



PHYLÜM VII 



Woodward) (Fig. 1464), froni the Goal Measures of England and North 

 America, is now the most completely known. It resembles Anaspides in 

 general form, in the segmentation of the body, the pedunculated eyes, the 

 characters of antenniiles, antennae, and even of the minute mouth-parts^ the 

 exopodites of the thoracic legs, and the form of the tail-fan. The only 

 important difFerence between the two, apart from the delicate lamellar gills 

 which could hardly be looked for in a fossil, is the presence in Falaeocaris of 

 a wedge-shaped first thoracic somite, which, in Anaspides, is fused with the 



head. 



Uronectes Bronn (Gampsonyx Jordan and v. Meyer) (Fig. 1465), from the 

 Lower Permian of Saarbrücken, resembles Falaeocaris, 

 but has one of the anterior pairs of legs enlarged and 

 armed with spines. Acanthotelson 

 Meek and Worthen, and Pleurocaris 

 Calman, from the Goal Measures of 

 Illinois and of England respectively, 

 have the first thoracic somite fused 

 with the head and may perhaps have 

 no thoracic exopodites. These exo- 

 podites are also stated to be absent in 

 Gasocaris Fritsch, from the Permian 

 Gaskohle of Bohemia. Palaeorchestia 

 Zittel (Fig. . 1466) and Neäotelson 

 (FSr''''coarMeai" ^^occhi, are less completely known, 

 -es ; Lisek, near Beraun, and are doubtfullv included in this 



ohemia. i/^ (after 



Fio. 1465. 



Fig. 1466. 



Uronectes fimbriatus 

 (Jordan). Rothlie- 

 gendes ; Lebach, Saxony. 

 V,. 



ures ; 

 Bc 



Fritsch). 



group. 



Division B. PERACARIDA Calman. 



Carapace, when present, leaving at hast four of the thoracic somites distinct ; 

 first thoracic somite always fused with the head. Eyes pedunculate or sessile. 

 Oostegites attached to some or all of the thoracic limbs in the female, forming a hrood- 

 pouch. 



Of the Orders included in this division, two, the Cumacea and Tanaidacea 

 are unrepresented in the fossil state. 



Order 1. MYSIDACBA Boas.i 



I 



The caridoid fades is retained. The carapace extends over the greater part of 

 the thoracic regton, but does not coalesce dorsally with more than three of the thoracic 

 somites. 



Among the caridoid forms known from Carboniferous rocks, PygocephaUs 

 Huxley, from the Engl.sh Goal Measures, has recently been shown by 



gSi 'so 1861 7of iSi «,;■ /*''''/™„''''°*^'' ''■'"" B""«'' Goal Meas„re.s. Q,,art. Journ 

 Sand ' /^ISs K vnx5ÄJ«;„°TTTh°^^ '" Carloniferous „f 



A,ner. Journ. Sei., 1897, ser. 4, vö . iv -S,trrö'/? 0^^!t™*° P°„"""" °f ^''«S"*^. '^■ 

 Mer,, 1907 ,lec S vol iv —P„irhn\r L""*""™; "■' On the genus Pygocepludm, etc. Geol. 



of l^oUand. Men;.te„i:-S^^!t;eatB*kta° "fSs'' °" ''*'■''' °™^*»"^^°f Carboniferous Rocks 



I 



