LichenCovered Branch 51 THIRD FLOOR EXHIBITS Int er tidal Sand Bodies These epo xy relief peels from the Minas Basin Bay of F undy No va S cotia preserve sedimentary structures from a modernday inter tidal z one The Bay of F undy records the highest tidal ranges in the world T renc hes were dug across a tidal bar in several places so that the pat terns within the bar could be seen in cross section While eac h of these specimens tells its own story to a sedimen tologist they are exhibited here primarily for their interesting textures Gifts from George deVries Klein Univ ersity of Illinois UrbanaChampaign As you round the corner you will see these specimens displayed on the walls above the stairs Dinosaur F ootpr ints These specimens contain trac ks made by dinosaur s w alking in mud and sand near ancient shores Over time the trac ks were co vered by more layer s of mud and sand and were buried deeply enough to be compressed and ce mented into roc k before being uplif ted and eroded to the surface ag ain The larger slab contains trac ks of several indi viduals The blac k number s on the specimens were painted by Charles H Hitc hcoc k who collected these trac ks in the Connecticut Ri ver V alley Massac huset ts be fore 1 840 Dinosaur s had not yet been identifed and Hitc hcoc k believed that these were the trac ks of giant birds P er manent loan from the Pratt Museum Amherst College Amherst Massachusetts through Gerald P Broph y Lic henCo v er ed Br anc hes Lic hens are an y of numer ous plants consisting of a fun gus usually of the class Ascom y cetes li ving in symbiotic relationship with cer tain green or bluegreen alg ae c haracteristically forming with a crustlik e scaly branc hing growth on roc ks or tree trunks Another specimen is on the outside w all south of the front door The limegreen lic hen is ali ve and requires occasional w atering to maintain its extremely slow growth Gift from S W arren Hobbs US Geological Surv e y Denv er Colorado As you descend to the second fooreast wing you will see the GSA Council Room p 39 and additional specimens Continuing downstairs to the frst foor will return you to the beginning of the tour