These fossils are of unknown origin. Because of great diversity in size 

 and shape, the conodonts have at various times been called worm teeth, 

 fish teeth, parts of arthropods, gastropods, and cephalopods. 



Arthropods 

 Eurypterids 



Eurypterids are extinct representatives of a group of animals which 

 include the spiders and scorpions. Up to nine feet in length, these arthro- 

 pods were scorpion-like in appearance. They possessed a thin, chitinous, 

 segmented shell and a tail which was either long and pointed or flat. 

 Jointed legs are found fossilized. Many eurypterids had large compound 

 eyes on the dorsal (upper) surface. 



Western New York is very well known for the eurypterids obtained 

 from its Silurian rocks. However, it is no longer possible to collect specimens 

 because the principal collecting locality, which was in the quarry behind 

 Bennett High School, is no longer accessible. Eurypterus lacustris is an 

 eurypterid known from specimens found locally. It averaged about a foot 

 in length and is characterized by large eyes and a pointed tail. 



The seal of the Buffalo Society of Natural Sciences depicts an 

 eurypterid. 



TRILOBITE Dalmanites 

 Trilobites 



Trilobites are an extinct group of insect-like animals which have left 

 abundant and varied fossils. Most are less than two inches in length 

 although they vary from less than one fourth of an inch to thirty inches. 



The animals were well protected on the dorsal surface by a hard 

 shield which was differentiated into three parts: a head (cephalon) some- 

 times possessing large compound eyes; a thorax often of numerous jointed 

 segments; and a spiny or rounded tail (pygidium). The body is character- 

 ized by an elevated ridge longitudinally along the center. 



Trilobites molted as they grew, casting off their old exoskeletons much 

 the same as insects do today. Many fossils are the castoff immature shells. 



