PALEOZOIC TIME — DEVONIAN. 



685 



865. 



of a common species of Favosites (honey-comb Coral, named from favus, 

 honey-comb), which is sometimes in hemispheres five feet across; 860, part of 

 the surface of a PhilUpsastrea, a common massive Coral, and 

 861, a fragment of a species of Cyathophyllum ; 863, a group 

 of clustered tubes scarcely radiated within, of the genus 

 Syrmgopora, broken from what was once a convex hemi- 

 spherical mass of branching tubes ; 864, a creeping tube, 

 having cells at intervals. 



3. Echinoderms. — Besides true Crinoids of several species, 

 some of them of very large size, there were the Blastoids one 

 of which is represented in Pig. 865. Though ovoidal in 

 form, it is related to the pentagonal Pentremites of the 

 Lower Carboniferous. 



4. Molluscoids. — Brachiopods were very numerous ; and Figs. 866 to 870 

 represent common species. The Terebratula family, the most abundant in 

 species in existing seas, has its species ; Fig. 870 is one of them : it shows 

 the opening at the beak. 



866-870. 



Nucleocrinus Ver- 

 neuili. Meek. 



Beachiopods. — Figs. 866, 867, Spirifer acuminatus ; - 868, S. gregarius ; S69, Productella subaculeata; 870, Cryp- 



tonella lens. Pigs. 866 to 868 by Meek ; 869, 870, HaU. 



5. MoUusks. — The few LamelUhranchs described include the following 

 kinds, with species of the Avicula family and others. 



871. 



872. 



.^^' 



Lamellibeanchs. — Fig. 871, Paracyclas proavia ; 872, Conocardium cuneus. Meek. 



Among Gastropods occur many species of the genus Platyceras, one of 



