76 PUBLIC PARKS OP IOWA 



state, like bottle grass (Asprella hystrip), Cinna arundinacea, blue grass 

 (Poa pratensis), little blue stem (Andropogon scoparius), rice cut grass 

 (Leersia virginica and L. oryzoides), but the tops of open clay hills are 

 covered with wild grass (Danthonia spicata), and on one or two of the 

 clay ridges crab grass (Panicum filiforme), small and diminutive in most 

 cases occurs; meadow grass (Poa debilis), first found by Barnes and 

 Miller; dropseed grass (Muhlenbergia sobolifera and M. Wildenovii) are 

 found in damp, shady woods. The rocky talus supports Goldie's fern 

 (Aspidium Goldianum), wood fern (Aspidium spinulosum) and beech 

 fern (Phegopteris polypodioides) only in one place. These species will 

 soon disappear. Nearby is found Alpine enchanters nightshade (Cir- 

 caea alpina). The rich woods contain another beech fern (Phegopteris 

 polypodioides) in considerable quantity. Christmas fern (Aspidium 

 acrostichoides) occurs in damp rich woods. Club mosses (Lycopodium 

 lucidulum and L. complanatum) have both been found by Mr. Reppert 

 on the sandstone talus. One of the hillsides contains a considerable 

 quantity of huckleberry (Gaylussacia resinosa). It occurs with wild oat 

 (Danthonia spicata) and crab grass (Panicum filiforme), hawkweed 

 (Hieracium scabrum and H. Canadense) occur with oat grass (Dan- 

 thonia). Both are rare in Iowa. Prairie clover (Lespedeza reticulata) 

 and rattlesnake plantain (Goodyera pubescens) are associated with 

 huckleberry (Gaylussacia). 



The region is interesting because of the number of native ferns found 

 there. I may mention the following ferns found by me on the trip made 

 on May 18th: The rocks were covered with walking leaf fern (Camp- 

 tosorus rhizophyllus), a little of the polypody (Polypodium vulgare), 

 woodsia (Woodsia .pbtusata), maiden hair fern (Adiantum pedatum), 

 Goldie's fern (Aspidium goldianum), small aspidium (A. spinolosum), 

 spleen wort (Asplenium felix, Foemina), brake (Pteris aquilina). 



THE NATURAL BRIDGE AND CAVES OF JACKSON COUNTY. 

 By James H. Lees, Geologist. 



One of the most unique regions of Iowa, because of the rarity of the 

 phenomena as well as of their natural beauty, is that including the natural 

 bridge and the caverns known as the Morehead Caves. These are lo- 

 cated in a small ravine about a mile from Maquoketa river in section 

 six of South Fork township, Jackson county, eight or nine miles north- 

 west of Maquoketa. They are a really wonderful group of objects, typify- 

 ing as they do the great erosive and dissolving power of running water 

 and combining in their features both the majesty and the beauty of Na- 

 ture's work. As the observer studies their rugged form and massive pro- 

 portions and considers the conditions which have given them their 

 present-day shape he can not fail to be filled with increasing awe and 

 wonder at the power of Nature's forces as well as with admiration of the 

 results here accomplished. 



The visitor who approaches the caves by way of the road from Ma- 

 quoketa enters the ravine rather at a right angle to its length and may 

 here cross it on a sort of platform far above the real floor, which may be 



