By E. J. Hill.

The state of Illinois has an area of about 55,000 square miles. It lies between the parallels 37° and 42° 30', thus giving a length of 5½° or about 380 miles. This north and south extension produces a milder climate in the southern part, but no fern of essentially southern distribution comes in except Polypodium polypodioides, though the two quill-worts of the state are perhaps better placed under this head also. It is the lowest of the north-central states in average altitude, the mean above sea level being about 600 feet, varying from 300 feet at the junction of the Ohio and Mississippi rivers to 1250 feet at the Wisconsin line in the extreme northwest part. As there is nothing in these extremes of elevation to effect material changes of temperature due to altitude, its floristic features are not much modified in respect of this. Anything of this character must be ascribed to local conditions, not general causes. Another factor that affects its floristic features is the dominance of prairie within its boundary, the forests and woodlands, sometimes very narrow strips, chiefly bordering its streams and lakes. Since lands covered with grass are not adapted to the growth of ferns, and consequently are limited in species, their number and variety must be much restricted for this reason. This must have been the case in the primitive condition of the prairies before they were so generally taken up for cultivation. The loss in the original fern-flora is slight in this regard when compared with that of flowering plants. As nearly all of the state is in the region of the glacial drift, the soil is influenced by this condition also. The ravines cut in the drift and in the underlying rock where it is reached, with their varying degrees of moisture and shade, show the greatest variety in fern-life, though a greater abundance of certain kinds may be found in woods and swamps. The prevailing rocks are limestone, but sandstones occur in some localities, especially along the Illinois and Rock rivers. These in some parts of the state, particularly in the coal measures, the area of which is large, may be interstratified with shales and slate. These rocks and the soils resulting from their disintegration and decomposition, taken in connection with those of the glacial drift, provide a fair range of edaphic conditions for the growth of ferns. It is evident that such as prefer a calcareous soil will be best represented, if any preference of this kind inheres in their nature.

It will be seen from the list that not quite one half (56) of the Pteridophytes accorded specific rank in “Gray’s New Manual of Botany” (115) are reported from this state. The genera are represented in larger proportion, 23 of the 31 given, or if Athyrium be separated, 24 of 32, or three-fourths of them. All the species of several of the smaller genera are found, up to three in the case of Osmunda, but all of none with species exceeding this number. The genus most fully represented is Equisetum, eight of the ten, or nine of eleven when E. robustum is given specific rank. To these must be added E. Ferrissii, not in the Manual.

Reliable data for the distribution of the ferns of the state are not very full. It is hoped that they may be made more complete by the co-operation of those into whose hands the list may fall. Many additions to the number of species can hardly be expected. Doubtless the state has been quite well explored in this respect. I find only two to add to those published by Patterson in 1876, Isoetes Butleri, described in 1878 from specimens found in Indian Territory (Oklahoma) but since found in this state, and Equisetum Ferrissii, a recent addition. The list is mainly a compilation made at the request of the editor of the Fern Bulletin. No special fitness for the task is claimed, since my personal knowledge of the region covered is almost wholly confined to five of the northeastern counties, Kankakee, Will, Cook, Dupage and Lake. Only casual trips of slight duration have been made to other places. The publication most relied on for the state at large is the “Catalogue of the Phaenogamous and vascular cryptogamous plants of Illinois,” H. N. Patterson, Oquauka, Ill., 1876. His catalogue of plants growing in the immediate vicinity of Oquauka has also been used. Friedrich Brendel’s “Flora Peoriana, Budapest, 1882,” (the German edition, but since given in English, I believe) has furnished some definite information for a district around the city of Peoria. The floras of H. H. Babcock and of Higley and Raddin for Chicago and vicinity have likewise been consulted, but as they respect territory mainly familiar to the writer, could be cited but little.

As explanatory of the plan followed I may state that I have first mentioned the localities or stations with which I am personally acquainted, and from which examples are in my herbarium unless very common throughout. Citations from Patterson’s catalogue for the state at large are entered in quotation marks followed by (P.). Where Peoria is given the authority is Brendel, where Oquauka, Patterson. A few have been furnished by V. H. Chase, who collected in Stark county and vicinity, and by Prof. Atwell of the Northwestern University, from data in the herbarium of the University.

OPHIOGLOSSACEAE.

Ophioglossum vulgatum (L.) “Wabash county, a single plant.” Schneck. (P.) Probably elsewhere, but easily overlooked.

Botrychium obliquum (Muhl.) In open woods, Cook Co., rare. “S. Illinois. Vasey, Schneck.” (P.) Peoria Co., V. H. Chase. Starved Rock. J. H. Ferriss.

Botrychium obliquum dissectum. (Spreng.) Peoria Co., V. H. Chase.

Botrychium virginianum. (L.) Common in rich woods in the northeastern part of the state, and probably throughout. It often occurs in colonies, sometimes of a dozen or more plants. In woods along Lake Michigan it readies a height of two feet.

OSMUNDACEAE.

Osmunda cinnamomea. (L.) Abundant in swampy areas in the northeastern counties, especially in peaty ground near Lake Michigan within the limits of the ancient glacial Lake Chicago. Swampy areas in sand barrens west of Kankakee, “Menard county. Hall.” (P.) Starved Rock. Clute.

Osmunda Claytoniana (L.) Frequent in swamps and wet woods from Kankakee county north in the eastern part of the state. Peoria, Brendel. Henderson Co., Patterson. “Moist ravines, common.” says Patterson for the state at large.

Osmunda regalis (L.) Has a range similar to the last and is quite frequent northeast in swamps and wet woods. Peoria, Brendel. Mason county, Bebb. Infrequent says Patterson for the state as a whole.

POLYPODIACEAE.

Adiantum pedatum (L.) Common throughout the state in rich woods.

Polypodium vulgare (L.) On cliffs of sandstone, La Salle and Ogle counties. “Common in Jackson and Union, French, Forbes.” (P.)

Polypodium polypodioides (L.) Common throughout the state in rich woods.

Pteris aquilina (L.) Copses and borders of dry woods. Frequent, or abundant in localities northeast. Starved Rock, La Salle county, Peoria, Brendel, Henderson, Patterson, Shelby, Mary Evertz. “Common.” for the state. (P.) Rare in Will county in the prairie region. Clute.

Cheilanthes lanosa (Michx.) “Rocks, St. Clair county, Brendel, and southward.” (P.)

Cheilanthes Feei (Moore.) Limestone cliffs by Mississippi river, Carroll county, “near Galena, Brendel; Pike county, Mead; Jackson, French.” (P.)

Pellaea atropurpurea (L.) Frequent on cliffs of limestone along the Desplaines river and its tributaries from Sag Bridge, Cook county, to Joliet, Will county, and in Kankakee and Carroll counties. Scarce on cliffs of sandstone, Oregon, Ogle county. Henderson county, Patterson; Kane county, W. J. Minium; Wedron, La Salle county, Ferriss. Reported for the state as general but “infrequent” in Patterson’s catalogue.

Pellaea gracilis (Michx.) Rare in thin soil in shelves of shaded and usually moist calcareous rocks. Sag Bridge and Lemont, Cook county, and Bounbonnais, Kankakee county. On moist sandstone rocks, Liberty Hill, Oregon, Ogle county; limestone, Aurora, Kane county; sandstone, Sheridan, La Salle county, Ferriss.

Asplenium angustifolium (Michx.) Henderson. Patterson, Peoria, Brendel “Rich woods, scarce for the state.” (P.) Joliet rare, Starved Rock more common. Ferriss.

Asplenium pinnatifidum (Nutt.) “On rocks, Jackson and Union counties, French; Pope, Schneck.” (P.)

Asplenium platyneuron (L.) “Open rocky woods, scarce.” (P.)

Asplenium ebenoides (R. R. Scott.) Reported from Jackson county, Ill., but without further reference in Fern Bulletin, vol. V., p. 13.

Asplenium Trichomanes (L.) “On shaded rocks, Jackson and Union counties, French; Wabash, Schneck.” (P.) Southern Illinois. Vasey. Starved Rock, two plants. Ferriss.

Athyrium filix-foemina (L.) Frequent in rich, moist woods in Cook and adjoining counties, as well as throughout the state as given by Patterson, Peoria, Brendel; Jackson, Saml. Bartley; Henderson, Patterson; Ravinia, Willow Springs, Cook county, Prince.

Athyrium thelypteroides (Michx.) “Near Glencoe, Cook county.” Higley Raddin; “Peoria and Fulton counties, Brendel and Wolff; Wabash, Schneck.” (P.) Joliet, rare; Starved Rock abundant, Ferriss.

Camptosorus rhyzophyllus (L.) On outcrops of limestone in the Desplaines valley in Cook and Will counties from Sag Bridge to Joliet. Abundant at Dellwood Park and in one locality at Sag Bridge, infrequent elsewhere. “Shaded rocks throughout but scarce.” (P.) Jo Daviess county, Pepoon.

Phegopteris hexagonoptera (Michx.) “Rich open woods and shaded ravines, chiefly in the northern portion of Cook county; infrequent.” Higley and Raddin (1891.) Peoria, Brendel; Henderson, Patterson; Jackson, Bartley; Joliet and Starved Rock, Ferriss. Patterson reports “frequent” throughout.

Phegopteris polypodioides (FÉe.) Starved Rock, La Salle county, “Menard county, Hall.” (P.)

Nephrodium noveboracense (L.) “Elgin, Kane county, Vasey; Wabash, Schneck, Swamps, scarce.” (P.)

Nephrodium Thelypteris (L.) Frequent or often abundant in swampy, wooded ground or open marshes, in Cook, Lake, Dupage, Will and Kankakee counties, Peoria, Brandel; Starved Rock, Clute. Frequent throughout the state according to Patterson.

Nephrodium cristatum (Michx.) Starved Rock, rare, Ferriss.

Nephrodium Goldieanum (Hook.) “Rich Woods, Peoria and Fulton counties, Brendel, Wolff; Makanda, Jackson county, Forbes,” (P.) Will county, La Salle county, Ferriss.

Nephrodium marginale (L.) Rocky bluffs, Starved Rock, La Salle county, Southern Illinois, Vasey. “Scarce” for the state. (P.)

Nephrodium spinulosum intermedium (Muhl.) Frequent in rich woods in the northeastern counties, Starved Rock, Clute. Patterson says “infrequent” for the state.

Polystichum acrostichoides (Michx.) Will county, “north part of Cook county,” Higley and Raddin; Henderson, Patterson; Peoria, Brendel; Jackson, Bartley. For the state, “infrequent.” (P.) The variety incisum is occasionally reported.

Cystopteris bulbifera (L.) Frequent on shelves and in crevices of limestone cliffs and shady ravines in the Desplaines valley in Cook and Will counties, and in Kankakee county, Henderson, Patterson, Peoria, Brendel; Starved Rock, abundant, Clute. Patterson reports for the state, “shaded rocks, frequent.”

Cystopteris fragilis (L.) Rather frequent in rich woods and occasionally on rocks in Cook, Lake, Dupage, Will and Kankakee counties; Henderson, Patterson; Peoria, Brendel; Jackson, Bartley. “Common” for the state. (P.) Very variable in its forms.

Woodsia obtusa (Spreng.) Scarce on limestone rocks at Lemont, Cook county, abundant on sandstone at Oregon, Ogle county, “Marion county, Bebb; Wabash, Schneck; and southward.” (P.) Joliet, Will county, Ferriss.

Woodsia ilvensis (L.) “On sandstone cliffs near Oregon, Ogle county, Bebb.” (P.)

Onoclea sensibilis (L.) Common in wet woods and swamps in the northeastern counties. Peoria, Brendel; Jackson, Bartley. For the state “common.” (P.)

Onoclea struthiopteris (L.) Wet shades, Starved Rock, La Salle county, Henderson, Patterson; Peoria, Brendel; Fulton, Wolff. For the state “infrequent.” (P.)

Dicksonia punctilobula (Michx.) “Wabash county, Schneck.” (P.)