96 GUIDE TO THE FOSSIL INVEETEBRATE ANIMALS. 



Gallery 

 VIII. 



Table-ease 



22. 

 Wall-case 



13b. 



This animal has the segments of the thorax all distinct, 

 covered by no carapace, and bearing limbs with swimming 

 branches and plate-like gills ; its eyes are stalked as those 

 of a lobster. Among British fossils the Syncarida are 

 represented only by poor specimens of Palaeocaris, also 

 found in the Coal Measures of Illinois. To show the char- 

 acters more plainly, a specimen of Uronectes [Gampsonyx\ 

 from the Lower Permian of Saarbriicken, Germany, has been 

 placed in the Table-case. 



Several Crustaceans now referred to independent Orders 

 Table-ease of Malacostraca were till recently united under the name 



Schizopoda (cleft-feet). Since certain 

 fossils, placed originally in the same 

 supposed Order, are too obscure to be 

 referred with certainty to any other 

 position, the division Schizopoda is pro- 

 visionally retained for them in the 

 exhibited series. Most are from the 

 Coal Measures, and among these Pygo- 

 cephalus, Palaeocrangon, and Anthrapa- 

 laemon are the better known forms. 

 Some of these outwardly resemble the 

 Decapoda, but appear to have some 

 thoracic segments still unfused with 

 the carapace. 



Next come fossils referred without 

 doubt to the clearly defined Order Iso- 

 poda. Of this Order the most familiar 

 representative is the wood-louse, but 

 most isopods are marine and some in- 

 habit fresh water. The flattened body 

 has a small head-shield (not a carapace) 

 ^ monWoodwardi,'Lo^et which are flexibly ioined seven tho- 



Coal Measures, Lan- . ^ i • i • x- 



cashire. a', antennuie ; i^^cic Segments, bearing each a pair of 

 a", antenna ; o, stalked walking legs ; plates attached to the 

 eye; c/, furrow separa- 13^363 of these linibs fomi a brood-DOUch 



tmg head-shield from ^ -, i.i i • i 



carapace, c; ah, abdo- for eggs and young ; the abdomen, which 



men; t, telson. En- bears giU-plates, is reduced in size, its 



larged 2 diani. (From segments partially fused, with a rela- 



H. Woodward, " Geol. .'^ . , /. i-, -r4- , 



Mag.," 1905.) tively large tail-shield. Here are shown 



fragments of the large Prearcturus, from 



Table-ease the Devonian near Hereford, whose isopod nature may be 



Wall^case Q.^^stioned. Cyclosphaeroma, however, from the Jurassic 



13b. rocks of ^Northampton and Solenhofen, is an undoubted 



Fig. 147. — Anthrapah 



