ECOLOGY OF ISLE ROYALE. 29 



is found Diervilla diervilla, Fire Weed, Prunus pcnnsylvanioa. Mountain 

 Maple, Mountain Ash, Birch, Mountain Alder, Willow, Sarsaparilla, 

 Wood Equisctiiiii, Oak and Ladies' Fern, Large-flowering Raspberry, 

 Cornus stolonifera and Clvntonia horeaUs. 



The open arid character of much of this station is reflected in the 

 grasshopper fauna, as follows: HihUscus tiiherculatus, Melatioplm 

 alaskanus, fasciatus and Gircotettix ferrucukitus. The butterfly, Basil- 

 arcMa arthemis Avas also taken here. The rare dragonfly, Ophiogmnphus 

 columhrvnus was also taken at this station, probably because of the 

 proximity of the rapid flowing outlet, which forms a trout stream. 



Station V, Substation 10. Long Island Gull Boahcry and Menagerie 

 Island. This station was examined solely for its bird life, which will 

 be discussed elsewhere in this report. This large Gull rookery is on Long 

 Island, Fig. 45, Avhich lies about one mile west of Menagerie Island 

 where Isle Royale Light is located. This bird clearly breeds upon the 

 middle and upper beaches. Long Island is formed by the upturned 

 edges of red sandstone and is exposed to the full sweep of the lake 

 waves, as is clearly evidenced by the bare rocks. The vegetation on the 

 island was not examined, as the time that could be devoted to the exam- 

 ination of the rookery was limited. But mention should be made of the 

 abundance of algae in the lake bordering the rookery, and of their 

 abundance in the rock pools, on the beach. 



Station V, Substation 11. Tamarack-Spnice Swamp. This station 

 includes a waterlily pond surrounded by zones of sedge, heath shrubs, 

 Tamarack and Black Spruce. A general view of the pond is shown in 

 Fig. J^6. It was located almost due west of the western end of Station 

 V, 2, and only a short distance northwest of the boat landing. 



In the pond, submerged, was Utricularia, Yellow Waterlily, 

 Potamogeton, and Brasenia (Water Shield) ; practically all the open 

 water was occupied by the Yellow Water Lily. At the edge of the 

 water grow the sedges, Fig. Ifl, which form a distinct zone, and the 

 Buckbean. The sedge zone also includes the Fqwsetum, Purple Cinque- 

 foil, Comarwn jialustre, a willow, Hypcricuin, Water Hemlock {Cicuta 

 hunifera), and the White Bog Orchid. Beyond the sedge zone comes 

 Sphagnum, Andromeda polifolia, Cassandra, patches of Labrador Tea, 

 Oxycoccus oxycoccus (Small Cranberry, abundant), Alder, Chiogene.^ 

 hispidula (Creeping Snowberry), Bunch Berry or Dwarf Cornel (Cornus 

 canadensis), Ealmia glauca, Pitcher Plants, Drosera intermedia. The 

 trees do not extend to the inner limit of the Cassandra zone. Cladonia 

 grew upon dry hummocks in this zone. In a few places, in depressions in 

 the tree zone, Eriophorum was found. The trees are Tamarack, Black 

 Spruce, and small Arbor Vitae. The general appearance of the Cassan- 

 dra and tree zones are shown in Fig. 48. 



The invertebrate fauna of this station was abundant and varied, but 

 the vertebrates were more limited. In the Water Lily and Pota- 

 mogeton zone the Stickleback, Eucalia inconstans, was taken, and at 

 the sedge margin, Ram^ clamitans. Water bugs are represented by Bel- 

 ostoma and Uwixa nymphs, and on the surface by the Water Strider, 

 Gerris rufoscutcllntus. A small shell, Phy.m aplectoides, was found in 



