Richard M. Holman THE DEPARTMENT OF CONSERVATION STATE OF INDIANA W. A. GUTHRIE, CHAIRMAN STANLEY COULTER JOHN W. HOLTZMAN RICHARD M. HOLMAN, SECRETARY PUBLICATION No. 7 Volume II RICHARD LIEBER DIRECTOR THE DEPARTMENT OF CONSERVATION NDIANAPOUI S: WM. B. BURFORD, PRINTER 1920 IN MEMORIAM LAKE MAXINKUCKEE A PHYSICAL AND BIOLOGICAL SURVEY BY BARTON WARREN E VERM ANN, A. M., PH. D. Director of the Museum of the California Academy of Sciences AND HOWARD WALTON CLARK, A. B., A. M. Scientific Assistant U. S. Bureau of Fisheries Biological Station, Fairport, Iowa VOLUME II PUBLISHED BY THE DEPARTMENT OF CONSERVATION STATE OF INDIANA 1920 Contents BIOLOGY- Page THE INSECTS 7 Order Aptera 7 Order Ephemerida 8 Order Odonata 10 Order Orthoptera 27 Order Hemiptera 29 Order Trichoptera • • 31 Order Coleoptera Order Diptera 35 Order Lepidoptera 37 Order Hymenoptera 39 THE MOLLUSKS 41 The Unionidse 41 Lakes and ponds as the home of mussels 41 Origin and character of the Maxinkuckee mussels 42 Distribution of mussels in the lake 44 List of Species 51 Mollusks other than Unionidae 72 THE CRUSTACEANS : 75 The copepod parasites 79 The crawfishes 83 THE LEECHES 87 THE PROTOZOANS AND CCELENTERATES 95 THE WORMS 100 THE SPONGES 100 THE PLANKTON 105 The plankton scum or wasserbluethe 110 THE FLORA 117 Introduction 117 THE AQUATIC FLORA : 119 Introduction .' 119 Uses of the aquatic flora 119 THE LAND FLORA 124 Introduction 124 General Floral Regions 128 COMPARISONS OF AQUATIC AND LAND FLORAS 133 THE ALG/E 1 38 Introduction 138 ANNOTATED LIST OF SPECIES 141 The Green Algae, etc 141 The Characese 157 The Diatoms, etc 161 The Aquatic Plants of Lake Maxinkuckee 165 The Aquatic Plants of Lost Lake 192 The Ferns, Fern-Allies, and Seed-bearing Plants 197 921897 THE INSECTS INTRODUCTION Unfortunately, no entomologist was assigned to the party study- ing the lake. No special study was, therefore, made of the insects. This is regretted, because so many species of insects or their larvaB bear an important relation to the life of the lake. The number of species that enter directly into the menu of the fishes of the lake is undoubtedly many and the total quantity consumed must be very great. Such study of the insects as we were able to make was there- fore purely incidental and necessarily very disconnected and in- complete. From time to time examples in various groups were collected. These were sent to the Bureau of Entomology of the United States Department of Agriculture, to the specialists of which we are indebted for their identification. For assistance in identifying the species in the various orders we are indebted to several specialists. Professor W. S. Blatchley has helped us with the Orthoptera, Dr. 0. A. Johannsen with the Diptera, and Mr. E. P. Van Duzee with the Hemiptera and other groups. An exception to this general statement may be made in the case of the Odonata, which were collected and reported upon by Dr. Charles B. Wilson, who spent a part of two summers at the lake and secured such species as were to be found during that time. ORDER APTERA THE SPRING-TAILS Snowfleas, probably Achorutes nivicola, were exceedingly abundant about the edges of the pools and ponds, especially about the woodland pond near Farrar's. They were very active, leaping from the moist leaves about the pond into the water or rather upon its surface. In places they would turn the snow black. On the occasion of a heavy snowfall late in winter an old inhabi- tant remarked: "This snow will remain until the bugs eat it up." He said that this was common belief and that in parts of Pennsylvania some of the late heavy snows disappeared, not by melting, but by being consumed by snowfleas! A curious super- stition. The snowfleas as they grow, often shed their skins on the sur- face of the water, the skin remaining as a thin, white pellicle. On March 17, 1901, they were abundant on the snow, and on November 1, 1904, many were seen at the edge of the lake. (7) 8 Lake Maxinkuckee, Physical and Biological Survey ORDER EPHEMERIDA THE MAY-FLIES The May-flies are probably the most important insects in rela- tion to the fishes of the lake. Their eggs are laid in the water, the larvae are aquatic, and both are fed upon by fishes. The May- flies themselves, at the close of their brief lives, fall upon the sur- face of the lake by the millions and furnish a vast amount of food to many species of fishes. Early in April the May-fly larvae begin to be conspicuous about the margins of the lake and in the ponds and quiet streams. They were first noted in numbers on April 4 (1901), and throughout the winter they were found more or less frequently in the bottom dredgings. About the fourth of April, they began to crowd up near the shore in great numbers with a peculiar wriggling motion. On April 5 they were found in immense numbers in a ditch and some small ponds near the Assembly grounds. On April 6, millions were seen in this ditch and they were very plentiful in many other places. They continued very abundant until about the fifteenth when they began to decrease in numbers, but the larvae were noted on the 19th, 20th, and 22nd. The first May-fly imago was noted on May 2. The next day many were seen in the woods indulging in an aerial dance. On the fourth, many were seen in the town of Culver, dancing in the air. From that date they kept increas- ing in numbers, while at the same time their larvae casts were more and more abundant in the water along the shore. By May 17, the woods were filled with insects on the wing, many of them May-flies, and the larvae were abundant in windrows at the water's edge. From May 18 to 21, they were noted by the millions. On May 19 and 20 great numbers of casts and dead adults were observed in the water and along the shore, and dead or dying adults were very abundant in the grass and weeds around the lake. On May 22, they began copulating and laying their eggs in the water, at the same time being caught in great numbers by the various kinds of fishes. The straw-colored minnows snapped them up greedily. We caught a number of the May-flies and threw them on the water where they were promptly seized by the fishes. They continued in considerable numbers until May 25, when a good many were seen, but none flying, and all rather numb. Not many were seen on the 26th. A few were noted in the afternoon of the 27th and 28th, and on the 29th a few stragglers were seen. On the 28th one was observed emerging and several noted that had just emerged. In Lake Maxinkuckee, Physical and Biological Survey 9 the evening a great many were seen flying about and on the grass. They leave their cast-off skins on the grass a few steps back from the lake shore. None could be seen on June 4, but on June 22 one was seen, the last of the season. All the above applies to a long, blackish, rather robust species with three long caudal setse. On June 7, were seen a few of a second species, more slender than the other and with only two caudal setaB. It is a common belief about the lake that many fishes die as a result of gorging themselves with May-flies, but this opinion was not sustained by the examination which was made of the stomachs of a considerable number of fishes found dead during May-fly time. In addition to the larger May-flies of early summer, a diminu- tive form of a light brown color, but semitransparent, was present in immense numbers in autumn, emerging one night, and laying their eggs on the surface of the water during the next day and evening. These were present in such numbers that they formed regular drifts about the base of a large bullseye lamp set on the pier, the insects flying toward the pier light and becoming tangled up together by their long and delicate caudal stylets. Although probably as abundant numerically as the large May-flies of spring, these minute forms did not attract the attention that the former did, because of their pigmy size and inconspicuous coloration. The lisping of the minnows and other little fishes such as skipjacks, along shore on fine autumnal evenings, was caused by their snap- ping at these little insects as they deposited their eggs on the water surface. A remarkable feature about the May-flies is their habit of moulting after the wings have formed, and after they have flown a little distance from the ]ake. It is astonishing how such a thin transparent membrane as their wings can be shed. The dark, heavy species alights on the grass to make this last change but a light transparent species of late summer is often not able to shed the skin from its caudal stylets, but bears the entire cast-off clothes on these, and is thus greatly impeded in its flight. The larvae of some of the large dark May-flies feed on the softer portions of old, dead leaves, in the bottom of the water, and some of them will, in a very short time, completely skeletonize a leaf, leaving only the delicate lace-work of the veins. 10 Lake Maxinknckee, Physical and Biological Survey ORDER ODONATA THE DRAGON-FLIES By Charles B. Wilson INTRODUCTION Like the May-flies, the Dragon-flies are all aquatic and consti- tute the most important group of insects to be found about the lake. They are also the most attractive and graceful, in spite of the obnoxious name of "snake-feeders," which has been bestowed upon them in the common local vernacular. They have not, of course, the remotest connection with snakes, nor are they poisonous or harmful in any way, as is popularly supposed. They are strictly carnivorous and often cannibalistic in all stages of development, the larger imagos and nymphs habitually eating the smaller ones. But they feed chiefly upon other animals such as flies, insect larva?, small crustaceans, worms, leeches, fish-fry and tadpoles. They seem to relish especially house-flies and culicids, and thus become of great economic importance through the destruction of these pests. That the curse of house-flies and mosquitoes is kept so delightfully within bounds at Lake Maxinkuckee is very largely due to the untiring ministrations of the dragon-flies. Their eggs are either laid in the water or inserted into the tissues of some water plant or floating fragment. As soon as the egg is hatched the nymph begins devouring other animals. Of course, it has to be content at first with very small ones, but as it increases in size and strength it becomes able to kill larger and larger ones until finally it includes small fish and tad- poles among its prey. The full-grown nymph of one of the larger dragon-flies is fully two inches in length with a stout muscular body and strong legs. As soon as it is fully matured the nyi.^ph crawls up out of the water on a rush stem, the leaf of a water plant, a stake, a board, or other convenient support, usually during the night or very early in the morning. As soon as it becomes dry the skin splits along the back, and the fully developed dragon-fly emerges. These old nymph skins may be found about the lake during the entire sum- mer, and often in the early morning the newly emerged imago may be seen perched on the skin or close by. Thirty skins were taken one morning from the inside of a boathouse on the west side of the lake. That the dragon-flies enumerated in the following list play a very important part in the economy of the fish life of the lake may be seen from several considerations. Lake Maxinkuckee, Physical and Biological Survey 11 1. They destroy multitudes of insect adults and larvse that would otherwise serve as fish food ; they are voracious feeders and they keep at it all their lives. 2. The nymphs of the larger dragon-flies are strong and agile enough to catch and eat the helpless fry of many of the larger fishes. They greatly prefer insect larvse but will kill the fish rather than go hungry. 3. On the other hand, many of the insects destroyed are ob- noxious to man. This is especially true of the mosquitoes, gnats, etc., which form the dragon-flies' favorite food. 4. The dragon-flies themselves, both adults and larvse, are eaten by the fish. The young nymphs when first hatched are nearly as good fish-food as insect larvse, and are easily overpowered by the small fish which frequent the shallow water where they live. As the nymphs grow larger they become too wary and too power- ful for these small fishes. At the same time they keep coming closer and closer to the shore so that the larger fish do not get a chance to capture them. This explains why so few nymphs were found in the fishes' food during July and August. During the winter and in the early spring, when other food is scarce, these dragon-fly larvse must share with the minnows in supplying food for the larger fish. That the adult dragon-flies are eaten by the larger fish is a matter of both direct observation and inference. Repeatedly in the effort to capture some of the more wary dragon-flies a speci- men would be knocked helpless into the water by a blow from the net. Often on these occasions before it could be picked up there would come a swirl in the water and it would disappear down some fish's throat. It was difficult, of course, to identify the fish with certainty, but Libellula pulchella and L. luctuosa were eaten this way on several occasions by Large-mouthed Black Bass, while Celi- themis eponina was taken by the Redeye. Several of the smaller damsel-flies were taken by smaller fish. Reliable anglers also testify that they have seen fish following a pair of dragon-flies, like Celi- themis eponina, which fly about close to the surface over the deep water, the female repeatedly dipping her abdomen beneath the water to deposit her eggs, and that the fish often jump for the dragon-flies. Again, dragon-flies are constantly getting into the water, par- ticularly during a high wind and after they have finished deposit- ing their eggs. A careful watch was kept for such individuals every day, but in only one instance during the entire summer was a dragon-fly observed floating on the water. Even this one was 12 Lake Maxinktickee, Physical and Biological Survey swallowed by a fish before it could be picked up; the inference, of course, is that the others were similarly disposed of. 5. Dragon-fly nymphs in all probability prey on leeches amongst their other food, and leeches are the most fatal parasites that infest the lake, killing numbers of fish annually. Anything that tends to reduce the number of leeches, therefore, will have great economic value because they have very few enemies so far as known. This relation between dragon-fly nymphs and leeches is worthy of careful study in the future. The author greatly regrets that the lateness of the season prevented the acquiring of any positive data on this point. Specimens of every dragon-fly mentioned in the following list were collected and personally identified by the author. The species are arranged according to the admirable list of "The Dragon-flies of Indiana" by E. B. Williamson, as published in the Report of the State Geologist of Indiana for 1900. Many additional facts have been taken from this list and the author also wishes to acknowledge his indebtedness to Mr. William- son for valuable criticism and advice given in private correspond- ence, and for the last four species here reported, which were col- lected by Mr. Williamson at Lake Maxinkuckee in May, 1900. The author could not begin his collecting until the middle of July, and it is practically certain that the months of May and June would add ten or a dozen more species to the list. LIST OF SPECIES 1. BOYERIA VINOSA (Say) A rare species, shy and wary, and a strong flier. It was not positively identified around any of the lakes visited, but was thought to have been seen flying over Lost Lake on several occa- sions. Three pairs were seen along the Tippecanoe River on Sep- tember 4, the females depositing their eggs in the edge of the weeds along the banks. One of these pairs was captured. 2. AESCHNA CONSTRICTA Say A species seen only occasionally during the summer, but becom- ing more common during the autumn, and finally in the middle of September congregating in considerable numbers around Hawk's marsh, which is situated about a quarter of a mile inland from the west shore of the lake. This species, as noted by Williamson, pre- fers the shelter of the bushes and rushes, and returns constantly Lake Maxinkuckee, Physical and Biological Survey 13 to alight on the twigs and branches after roaming about in search of food. It is very active, a strong flier, and often mounts to a con- siderable height in pursuit of its prey. Although the abdomen of the male is seen to be highly colored with blue on close examination, both sexes appear dull brown when flying about. 3. PERITHEMIS DOMITIA (Drury) One of the smallest species, frequenting the lily-pads and pick- erel-weed, flying close to the water, and habitually keeping below the larger and stronger species as noted by Needham. The males congregate on the lily-pads some little distance from the shore and are difficult to catch because they are very wary. They can dodge a net with facility, and especially because they fly so close to the water that it is very hard to manipulate the net. The females are found closer to the shore and are not nearly so numerous as the males. Their flight here in Indiana is anything but "rather weak and a bit clumsy" as Needham records for New York State. The author spent two hours one afternoon in early September along the edge of the pickerel-weed at Twin Lakes en- deavoring to catch some of these females which could be seen occa- sionally flying about, and finally had to come away without secur- ing a single specimen. The females seen were always unattended by a male and deposited their eggs close to the shore amongst the Chara and Spirogyra. One specimen that had been swept into the water by the net was seized and eaten by a fish, apparently a War- mouth Bass. The adults of both sexes were obtained at Lake Maxinkuckee, Lost Lake, Bass Lake and Twin Lakes. They were especially com- mon at Lost Lake around the Outlet where several nymphs were also obtained August 15, just ready to come forth as images. 4. CELITHEMIS EPONINA (Drury) One of the skimmers and the largest of the genus in the State, both sexes rust-colored throughout, with large brown spots on the wings, the male more brightly colored than the female. This species and Libellula luctuosa were the two most common dragon-flies at all the lakes visited. They appeared before our arrival and were still roaming about at the middle of September. The female of this species is nearly always held by the male when depositing her eggs, and the two are seen flying about together more frequently than any other species. Since the eggs are de- posited in the clean water, often a long distance from any vegeta- 14 Lake Maxinkuckee, Physical and Biological Survey tion, the species is more conspicuous than most others. Then, too, both sexes, but especially the male, are inquisitive, and perch on the very tops of the rushes to watch the intruder. If disturbed they return again and again to the same spot. This species is also less dependent on the weather than most others and may be seen flying about on cloudy days, during a high wind, or even in a driz- zling rain. The nymphs of this species are broad and flattened, with the lateral margins of the last two segments conspicuously serrate. They prefer a stump, a board, or the post of a wharf for their final transformation and the dried nymph skins may be found in such localities and often on the inside of boathouses. Adults of both sexes were taken at Lake Maxinkuckee, Lost Lake, Bass Lake, Twin Lakes, Yellow River and Hawk's marsh. A pair of this species which had been brushed into the water was immediately ^seized and swallowed by a large bass, probably Micropterus salmoides. 5. CELITHEMIS ELISA (Hagen) Not as common as the preceding species and considerably smaller. In the coloration the red is more prominent, particularly toward the tip of the wings. The sexes do not fly about together as does C. eponina; the female keeps well out of sight among the rushes and dense vegetation back from the water's edge. The male, however, perches on the tips of the rushes and is nearly as inquisitive and conspicuous as the preceding species. The nymphs are similar to C. eponina but smaller, and they prefer a rush stem for their final transformation, and the dried nymph skins are found in such places. Adults were obtained at Lake Maxinkuckee, Lost Lake, and Bass Lake; the nymphs were obtained from Lost Lake. 6. CELITHEMIS FASCIATA Kirby A rare species only seen once during the entire summer. It can be distinguished at once from the two other species of the genus by its color, the general tone and the spots on the wings being black rather than reddish brown. It is about the size of elisa and re- sembles it in its habits, the female remaining hidden among the vegetation along shore, while the male roams about in the rushes over the water. About a dozen specimens were obtained at Twin Lakes on August 31, and they were the only ones seen. Lake Maxinkuckee, Physical and Biological Survey 15 7. LEUCORHINIA INTACTA (Hagen) This is the species commonly known as "whiteface," the desig- nation expressing the chief peculiarity, a white face sometimes tinged with yellow but always contrasting strongly with the sur- rounding dark color. It frequents the marshy flats around the lake, flying close to the water among the stems of the water plants, so that it requires some search to find one and more maneuvering to capture it. The eggs are laid close to the shore and the only fe- male seen ovipositing was perched on a rush stem with the poste- rior half of its abdomen beneath the water. The nymphs are large with an ovate abdomen, the dorsal hooks of which are as long as the segments which bear them. Found in Lake Maxinkuckee and Lost Lake. 8. SYMPETRUM VICINUM (Hagen) This is an autumnal species, not appearing until late in the sum- mer, and is one of the smallest found. It resembles the following species closely in size and body color, and the two can be distin- guished only by the shape and size of the hamulaB and abdominal appendages of the male, and by the structure of the vulvar lamina in the female. It flies about as much over the shore as it does over the water, and like the following species has a habit of hover- ing in the air, holding itself stationary by the rapid vibration of its wings. It was found in considerable numbers in Hawk's marsh and along the Tippecanoe River, and was the last species to be seen after frost came. 9. SYMPETRUM CORRUPTUM (Hagen) Very similar to the preceding in coloration, especially after the original markings have disappeared and the body has become a dark red. It is considerably larger than vicinum, is a more rapid flier, and rather more wary; and for these reasons very difficult to capture. Only a few specimens obtained from Yellow River late in August. 10. ERYTHEMIS SIMPLICICOLLIS (Say) This species has a wide distribution and is especially common around the swamps and marshes and along shore. Hawk's marsh, the southern inlet, and Green's marsh between Lost Lake and Lake Maxinkuckee, swarmed with these dragon-flies during the entire summer. They usually remain in the shelter of the dense herbage, and often squat on the ground like Gomphus. When they alight it is nearly always near the ground or the 16 Lake Maxinkuckee, Physical and Biological Survey water. They may often be taken pairing in such places, and pre- fer to lay their eggs in the shallow water along shore, amongst the yellow algae, where the water is scarcely deep enough to cover them. They feed largely on Diptera. Found at Lost Lake, Lake Maxinkuckee, Twin Lakes, Yellow River, and Tippecanoe River. 11. PACHYDIPLAX LONGIPENNIS (Burmeister) A very cosmopolitan species found over the whole United States, Mexico, and the Bahama Islands. Both sexes are swift fliers, and as the males, which are most in evidence, hover near the surface of the water and in among the vegetation they are difficult to catch. The females remain at some distance from the water when not ovipositing, and so are less difficult to capture. When ovipositing both sexes fly in and out among the cow-iilies and arrowheads where it is hard to strike with a net, and when they do alight it is usually on the sides of the lily stems close to the water. This species has the curious habit of drooping its wings and elevating its abdomen when resting, so that the insect ap- pears to be trying to stand on its head. As Williamson remarks, this simply furnishes the large Libellulas an excellent mark to nip at, and the author has repeatedly seen L. luctuosa and L. pulchella snap at the tip of the elevated abdomen and drive the Pachydiplax away, but has never seen one of the latter killed. This species was found during the entire summer in every lo- cality visited. 12. LIBELLULA LUCTUOSA Burmeister This was the most abundant of all the dragon-flies, and was found on all the lakes visited. It seems to prefer the higher and drier ground and was not usually found near low and swampy places. It is a strong flier and often pauses and holds itself stationary by rapid vibration of its wings. It is also inquisitive, searching into everything, and often re- turning to the same place when missed by the net. When fishing, the author has repeatedly seen them snap at the cork float on the fishing line, both while it was in the air during the casting and while it was floating on the surface of the water. • When alighting they often prefer the side of a rush stem, or even the bare ground. The eggs are deposited in the shallow water near the shore, the female hovering over the spot and re- peatedly dipping her abdomen beneath the surface in almost the same place. The black markings of the wings make this species very conspicuous, especially in the male where they are contrasted Lake Maxinkuckee, Physical and Biological Survey 17 with white. A male of this species was the only dragon-fly found during the entire summer floating in the water. On two occasions when knocked into the water by the net, images were seen to be eaten by Redeyes. Found on the northern and western shores of Lake Maxin- kuckee, at Lost Lake, Twin Lakes, and Bass Lake. 13. LIBELLULA INCESTA Hagen An extremely wary species, the males frequenting the tall reeds and rushes along shore. They are constantly on the watch and will not allow the collector to approach near enough to strike them with the net. They are also easily frightened and at once retire out of sight and remain hidden. No female was found during the entire season, and they must have been concealed in the grass away from the water's edge. This species was only rarely seen around Lake Maxinkuckee and Lost Lake, but was fairly common along the Outlet between the two lakes. 14. LIBELLULA CYANEA Fabricins Like the preceding, only the males of this species were found, and they frequented the tall reeds and rushes along the Outlet in company with incesta. They were not quite so wary and they also stay closer to the ground, alighting on the sides of the rushes or on broken stems. The bi-colored pterostigma and the tinges of color adjacent to it, and also at the base of both pairs of wings, can be distinguished at some distance and at once separate this species from any with which it would be likely to become con- fused. The females kept themselves so closely hidden that not one was seen during the season. Found rarely in Lake Maxinkuckee and commonly along the Outlet in company with incesta. 15. LIBELLULA QUADRIMACULATA Linnaeus This beautiful species was the most widely distributed and, next to L. luctuosa, the most abundant of the large dragon-flies. It is especially a pond-loving species, but was found also along the banks of the two rivers visited, along the banks of several of the cross-country ditches, around pools in the country barnyards, and even occasionally skimming the fields at some distance from the water. It is a strong flier and fairly wary. It also alights but seldom and keeps excellent watch. But it is also quite curious, and once or twice when the net was held out quietly it flew up near enough to be caught. 2— 17618— Vol. 2 18 Lake Maxinkuckee, Physical and Biological Survey A bass, presumably Micropterus salmoides, was seen to rise and seize an imago of this species which had been knocked into the Yellow River with a sweep of the net. Another imago was seized and swallowed under similar conditions in Lake Maxinkuckee by a fish which could not be distinctly seen. To these direct observations may be added the fact that, in spite of their abundance, not a single example was found floating on the water during the summer. The eggs are deposited near the shore, by repeated dips of the abdomen beneath the surface at nearly the same spot, similar to the practice of L. luctuosa. The sexes are occasionally seen paired, but the female is usually alone during egg deposition. Found at all the localities visited but especially abundant along the west shore of Lake Maxinkuckee. 17. PLATHEMIS LYDIA (Drury) A large and beautiful species, as strong a flier as the preceding, and considerably more wary. The old pruinose males are very conspicuous, their white bodies showing at a very long distance against the dark background. They also proved to be the most difficult to capture of any species, and only after repeated trials and numerous disappointments could one be gotten into the net. This species seems to prefer the creeks and inlets rather than the open water of the ponds. The sexes do not pair during ovipositing, and the female has a curious habit of placing her eggs in the water on the top of an old lily-pad whose center has become submerged. The male is a tireless forager and flies back and forth over the same beat until the supply is apparently exhausted. Found in the Outlet between Lake Maxinkuckee and Lost Lake, at the South Inlet, and along several streams emptying into the Yellow River. 18. CALOPTERYX MACULATA (Beauvois) This beautiful black damsel-fly does not come out in the open but sticks to the banks of the small streams where the thick vege- tation throws always a cool shade. They fly slowly and not very strongly with a sort of fluttering motfon. Their black wings, unmarked save by the white pterostigma in the female, and the bright metallic sheen on the abdomen, make them conspicuous amid the foliage. They congregate in consider- able numbers, and where conditions are favorable the banks of the stream will be fairly lined with them. Their eggs are deposited amid the weeds and loose debris near the bank, the sexes pairing during oviposition. Lake Maxinkuckee, Physical and Biological Survey 19 A single male was captured on the Outlet between Lake Maxin- kuckee and Lost Lake. They were found in great numbers on the Yellow River, Tippecanoe River and in some of the cross-coun- try ditches to the west of Culver. 19. HETAERINA AMERICANA (Fabricius) A species that is common around rocky ripples in the streams and rivers where the water is shallow and the banks are grown up with the water willow, Dianthera. It stays close to the water's edge on the leaves of the willow and does not fly far even when dis- turbed. When flying, the bright red spots at the base of the wings of the male make it conspicuous but on alighting these spots are concealed by the folding of the wings. The eggs are deposited on the willow leaves at the water's edge, and the sexes are paired during the process. A blind sweep of the net along the willows at such times will often capture ten or a dozen pairs. Very common along the Outlet, at Yellow and Tippecanoe rivers, and in the cross-country ditches to the west of Culver. 20. HETAERINA TRICOLOR (Burmeister) This species frequents the same localities as the preceding, and is very similar to it, the chief difference being in the posterior wings of the male, which are brown instead of red. It is not therefore as conspicuous when flying as the preceding, but when at rest the only appreciable difference is one of size, tricolor being a little the larger. Its eggs, like those of the pre- ceding species, are deposited in the weeds at the water's edge, the sexes pairing during oviposition. Found at Tippecanoe and Yellow rivers, and in a cross-country ditch close to the Tippecanoe. 21. LESTES UNGUICULATUS Hagen This species is somewhat smaller and not so dark colored as the two which follow. The dorsal surface of the abdomen is an iri- descent, metallic green, turning to pruinose in mature specimens. The white color at either end of the pterostigma furnishes a good mark for identification. It flies swiftly and hides in the dense vegetation around the marshes and along the shore, coming out only to lay its eggs. Found in considerable numbers at Hawk's marsh late in Au- gust and rarely along the Outlet between Lake Maxinkuckee and Lost Lake. 20 Lake Maxinkuckee, Physical and Biological Survey 22. LESTES FtfRCIPATUS Rambur Nearly as large as vigilax, the males with slender and nearly black abdomens, the pterostigma entirely black in both sexes. This is also a swift flier and a frequenter of the marshes and sedges, but it does not seem to remain concealed as persistently as unguiculatus. Williamson says it is the first of its genus to ap- pear in spring, and it was found late in August at Hawk's marsh, where it was taken in connection with the preceding species. It was not found elsewhere. 23. LESTES VIGILAX Hagen Notably larger than the preceding species and more brightly colored, its colors, however, harmonize so well with its environ- ment as to effectually conceal it. It is a slender and graceful spe- cies, preferring the rushes and weeds around the lake rather than along the streams. Its eggs are deposited amid the rush stems and the sedges, the sexes pairing during oviposition. The male retains such a firm hold of the female at this time that the two may not only be taken together but they may be killed and placed in the preservative still fastened together. Found in special abundance in Lost Lake around the Outlet and at the South Inlet of Lake Maxinkuckee and rarely along the west- ern shore of the latter lake. 24. ARGIA MOESTA PUTRIDA (Hagen) A large and dull-colored species which frequents the open shore where there is plenty of sunshine. They do not alight so much as the other species on the weeds and grasses but upon boards, sticks, stones, etc. They are not as lively as the other species and allow a close approach and easy capture. In every instance observed the eggs were being deposited in the yellow, filth-laden algas close to the shore. The male also, in these particular instances, held his body suspended above the fe- male at an angle of about 45° by the rapid vibration of his wings. He was not seen to be drawn under the female,, but the observa- tions were very limited. Found only at Aubeenaubee Bay in Lake Maxinkuckee and amid the pickerel-weed on Lost Lake. 25. ARGIA VIOLACEA (Hagen) A common species which remains all summer and may be found along the shores of the lake anywhere. It prefers the dense vege- tation close to the shore, and is also found along the banks of the Lake Maxinkuckee, Physical and Biological Survey 21 cross-country ditches. The sexes are usually found paired and the eggs are deposited in the tissues of decaying weeds and stems float- ing at the surface. During oviposition the male holds his body suspended in the air after the manner just described for putrida. The eggs are large and dark-colored and can be easily found in the decaying tissues. The violet color of the male shows up plainly among the blue and red, the orange and the brown of the species with which it associates, and is a distinguishing character. Found in all the localities visited. 26. ARGIA SEDULA (Hagen) This species is found with the preceding in the rank vegetation along streams and ditches. The males of the two species can be told at once by their color, violet in violacea and a deep blue in sedula. The females can then be told by their association with the males. The eggs are deposited similarly to those of violacea in the tissues of decaying matter floating at the surface. This species is not nearly so common as the preceding and was found in only two localities, along the Outlet between Lake Maxinkuckee and Lost Lake and at the South Inlet. 27. ARGIA APICALIS (Say) This species is similar to pntrida but is brighter colored and is not found in similar localities, preferring the streams and rivers to the open lake shore. Here it lives amid the rank vegetation, venturing out only after food or for the purpose of depositing its eggs. These latter, furthermore, are never deposited in the dirty algse near the shore but in the clearer water some distance out. About 20 specimens of this species, including both sexes, were taken on the Tippecanoe River in September. 28. CHROMAGRION CONDITUM (Hagen) This species was found in considerable numbers at Hawk's marsh in company with two species of Lestes. They seemed to prefer this cool, shaded swamp, and were not seen in the open or anywhere along the lake shores. They were mating and the fe- males were depositing their eggs in the few pools near the center of the water where any water was visible. Of necessity the eggs were laid in the weeds and lily-pads with which the pools were nearly choked. Several specimens of both sexes were secured. 29. NEHALENNIA IRENE Hagen A very small but handsome species found in the damp vegeta- tion along some stream or ditch. In addition to its small size it is 22 Lake Maxinkuckee, Physical and Biological Survey bright green in color, and easily overlooked in the green foliage. The sexes are usually paired and the female deposits her eggs on the stems of rushes lying in the water. The eggs are pale in color and fastened on the surface rather than inserted in the substance of the rush. Found along the outlet below Lost Lake. 30. NEHALENNIA POSITA (Hagen) Another tiny species, even smaller than the preceding, living amongst the cow-lily stems and pads out in the open lake. The male is usually bronze-black in color, ornamented with bright yel- low and is much easier to distinguish than Irene. The eggs are laid similarly on floating vegetation. Found among the cow-lilies in Lost Lake, and in the South Inlet of Lake Maxinkuckee, where it is fairly common. 31. ENALLAGMA HAGENI (Walsh) A brightly marked blue species found in great numbers on the rushes in shallow water along the shores of Lake Maxinkuckee and Lost Lake. It was more abundant in July than in August, and had nearly disappeared by the last of the latter month. The sexes are nearly always paired and the female seems to prefer depositing her eggs on a broken or floating rush stem. The eggs are dark in color and are fastened on the surface of the floating material in great black patches. The males of this species like those of Argia have the habit of holding themselves in the air by a rapid beating of the wings while the female is ovipositing. As many as 50 or 60 couples may often be seen on the same rush stem, literally cov- ering all the available space. They are quite tame, allowing the boat to pass so close that one could touch them by extending the arm. 32. ENALLAGMA CARUNCULATUM Morse Another bright blue species, a little larger than the preced- ing and not nearly as common. The two were found associated on the rushes in Lake Maxinkuckee and cannot be distinguished with certainty except by an examination of the abdominal ap- pendages in the male. Their habits of pairing and oviposition are similar, but the eggs found were not as dark in color as those of hageni. This species probably occurs on the other lakes but did not happen to be found on the days when those lakes were visited. Lake Maxinkuckee, Physical and Biological Survey 23 33. ENALLAGMA DIVAGANS Selys A much darker species appearing almost black when flying and found in company with the two preceding on the rushes in the open lake. The habits of oviposition are similar but only a few couples were found and the species appears to be rare. 34. ENALLAGMA EXSULANS (Hagen) Another of the darker species, the black showing mostly when flying. It is, next to hageni, the most abundant species among the rushes, and was also found in the open herbage along the banks of the Yellow River. 35. ENALLAGMA SIGNATUM (Hagen) An orange and black species easily recognized by its colors. The abdomen is noticeably slender, the black markings showing more prominently in the male while flying, and the orange mark- ings of the female. When at rest both sexes show the orange markings plainly enough to distinguish them from the associated species of the genus. Then, too, they are not common among the rushes, but prefer the lily-pads at some distance from the shore. Found in the outlet of Lost Lake and in the South Inlet of Lake Maxinkuckee. 36. ISCHNURA VERTICALIS (Say) This is one of the species in which "at the time of imagination two distinct color types of females appear." In one of these the black, bluish, or grayish colors predominate, while the other is brilliantly streaked with orange. Both of these types were found with the green and black males upon the lily-pads in the outlet of Lost Lake early in August. Their flight was markedly weak and there was no trouble in capturing them. They alight, however, only on the tops of the lily-pads and so the net must be carried down into the water in order to capture them. 37. ISCHNURA KELLICOTTI Williamson This species also has both the black and the orange females, the former seemingly the more abundant. It was not found any- where around the lake with the exception of a single male taken at the South Inlet. But it was common at Hawk's marsh and many specimens of both sexes and of both types of females were secured there. The bright blue on the upper surface of the pterostigma of the anterior wings of the male serves to distinguish this species from the preceding. This is a species first discovered by William- son and therefore of peculiar interest in the state. 24 Lake Maxinkuckee, Physical and Biological Survey 38. ANOMALAGRION HASTATUM (Say) This is another genus with two types of female, the orange and the black. It is found flying about in the shelter of the pickerel- weed along the shores of Lost Lake and at the South Inlet of Lake Maxinkuckee, and also at Hawk's marsh. It sticks closely to the weeds and does not usually venture very far from them even to get its food. Both sexes alight on the side of a weed stem when ovipositing and the female then backs down into the water. The species was fairly common at the places mentioned. Mr. E. B. Williamson of Bluff ton, Indiana, reports the following species not found by the present writer at Lake Maxinkuckee : 39. Anax junius, May 24, 1900, two males and one female. 40. Tetragoneuria cynosum, May 21 and 25, 1900, two males. 41. Tramea lacerata, May 21. and 25, 1900, two males. 42. Enallagma calverti, May 27, 1900, two males and one female. A few of our field notes for May and June, 1901, may be given here. May 1, first dragon-fly seen ; 5th, several dragon-flies ; 14th small dragon-fly; 15th, many small dragon-flies (Agrionids) ten- erals arise out of grass in damp ponds ; 16th, dragon-flies of various sorts, mostly slender, as yesterday, some robust forms; all look pale; 18th, some large dragon-flies seen; 20th, dragon-flies come out of the water, emerging in great numbers; 22d, some dragon- flies came out; 23d, a good many dragon-flies seen, both large ones and slender steel-blue ones; some of the latter copulating; 29th, one large and one small dragon-fly seen ; 30th, several dragon-flies seen. June 3, many slender steel-blue dragon-flies copulating on rushes; 6th, great numbers of small dragon-flies in grass near lake; 8th, many dragon-flies, a small slender species coming out of cases at noon ; 12th, dragon-flies, small ones quite abundant. Saw two large teneral dragon-flies in morning and several larvae in afternoon; 17th, multitudes of small blue-green dragon-flies near Outlet Bay in evening; 20th, dragon-flies laying; 21st, good many small dragon-flies; 22d, dragon-flies plentiful. In 1904, a rather slender red-bodied dragon-fly was noted ovi- positing, and another was seen October 18. They seemed at this time to be the most abundant species. They were noted copulating and flying about October 26 and 27 and so on until November first. Two years after the completion of the above list, another visit was made to the lake earlier in the season and a number of addi- Lake Maxinkuckee,, Physical and Biological Survey 25 tional species were observed. These are probably as common as many of the original list, but they escaped notice during the first season, or they may have appeared and disappeared previous to the beginning of observations. 43. GOMPHUS EXILIS Selys Common on the banks of the Outlet June 28, 1909, where it alighted on the grass and on the lily-pads and spatter-docks over the water. Of nine captured, eight were males, all of which were feeding on teneral damselflies. 44. GOMPHUS LIVIDUS Selys Captured at the Gravelpit on the west shore of the lake July 1, in the grass along shore and back some distance from the water. Unlike most species of this genus, it alights on trees and bushes as well as on the ground. 45. GOMPHUS FURCIFER Hagen A single female was captured at the Gravelpit in company with the preceding species July 3. She was holding a teneral Tet- ragoneuria, which was about half eaten. 46. GOMPHOIDES OBSCURA (Rambur) Common along the sandy beaches on the western side of the lake June 30. A pair that were mating and several single males and females were secured. This species has the habit of perching on the reeds out in the water after the manner of Celithemis, but it chooses short and stiff reeds rather than tall ones that sway in the wind. It flies only a short distance from its perch and returns to the same spot repeatedly. In 1909 these dragonflies were still common on July 15, but none was seen in other years. 47. ANAX JUNIUS (Drnry) Common around Lost Lake and along the Otulet on June 26, but not any seen on Lake Maxinkuckee. Afterward, on July 14, a single male was secured at Norris Inlet. 48. EPICORDULIA PRINCEPS (Hagen) Common in Lake Maxinkuckee and Lost Lake June 27, where they were patrolling the shore after the usual manner of this species. A single one was seen at Norris Inlet July 14. These are the only records for the species. 26 Lake Maxinkuckee, Physical and Biological Survey 49. TETRAGONEURIA CYNOSURA (Say) Common at Lost Lake where it flies about over the water con- tinually for long periods without alighting. Eight specimens were secured at the Gravelpit on Lake Maxinkuckee July 3, but the species disappeared very quickly after that date. 50. LADONA EXUSTA (Say) A few were seen on the east bank of the Outlet along the edge of the woods July 4, in company with Libellula incesta and L. cyanea. Several pruinose males were captured, and the species was afterward seen along the west shore of Lake Maxinkuckee. 51. LIBELLULA PULCHELLA Drury Common along the west shore of Lake Maxinkuckee in 1909. A large and powerful dragonfly which captures and eats many moths and small butterflies as well as other insects. It is more watchful and wary than many of the other species, but while eat- ing, can be approached easily. 52. TRAMEA LACERATA Hagen A single male captured as it was flying along the shore of Lake Maxinkuckee. The black bases of the hind wings are very conspicuous when the insect is on the wing and make it easy to identify. Many were seen along the west shore, particularly at the Gravelpit, and it was also noted at Norris Inlet on July 14. 53. SYMPETRUM RUBICUNDULUM (Say) Several specimens were captured in Hawk's marsh in 1908, and a single male on the banks of the Outlet in 1909. 54. LESTES CONGENER Hagen A single pair taken together in Hawk's marsh August 24, 1908. 55. ENALLAGMA GEMINATUM Kellicott A single pair taken together in Lost Lake August 22, 1908. 56. ENALLAGMA POLLUTUM (Hagen) Two pairs taken together in Lost Lake on the lily-pads Au- gust 22, 1908, and a single male on the lily-pads at Norris Inlet August 25. Lake Maxinkuckee, Physical and Biological Survey 27 ORDER ORTHOPTERA GRASSHOPPERS, CRICKETS, KATYDIDS, ETC. Even if they had nothing to do with the lake and its life, a dis- cussion of the insects of the region, or, indeed, of the insects of. any region, without mention of the Orthoptera would be, to use a singularly unhappy but hackneyed simile, like the play of Ham- let with Hamlet left out; for there is no other group of insects more prominent, perhaps one could even say so prominent, in the consciousness of men. What the gaudy butterflies are to the eye, the Orthoptera are to the ear. Indeed, grouping the various in- sects according to the sensations caused by the most familiar mem- bers we might say that we know the Hemiptera by the sense of smell,* the Diptera by the sense of touch, the Lepidoptera by the sense of sight, the Hymenoptera through their works and indirectly by the sense of taste, and the Orthoptera by the sense of hearing. This group it is that adds to the thought of insect life nearly all of its lyrical element ; and it is probably on account of this that the one notable exception is popularly known as the "locust", just as country boys think of the chimney swift as a "swallow" because of its general similarity in habits. As will be seen later, how- ever, one group of these insects is of peculiar interest and bears a special relation to the life of the lake. Not all the Orthoptera are choral. There are the cockroaches, which are, very fortunately, scarce or absent in the houses about the lake. A wild, or native species was, however, abundant and nearly ate the bindings off of some books kept in the tent, and the lank, silent walking-sticks, Diapheromera femorata, were not rare in woodlands. Of greatest economic importance were the grass- hoppers. This group of insects is important because certain species enter so largely into the food supply of many species of fishes. By all odds the most popular as well as the most killing bait used by the anglers who frequent the lake is the grasshopper. It is a choice bait and always attractive, not only to both species of black bass, but also to the rock-bass, bluegill and yellow perch, and not wholly rejected by the warmouth, crappie, calico bass, wall-eyed pike, pumpkinseed and other sunfishes. It has been shown elsewhere in this report that the small boys who sell grasshoppers to the anglers at this lake derive therefrom an annual income of at least $200. *We feel mosquitoes, smell bugs, taste honey (and if reports of lumber camps are to be believed, pome of the men eat the large black ants for their acid taste and intoxicating effects), see butterflies, and hear crickets, grasshoppers and katydids. 28 Lake Maxinkuckee, Physical and Biological Survey Fortunately for the angler, grasshoppers of various species are abundant in the fields, meadows and waste places about Lake Max- inkuckee. The prairie meadows to the west of the lake have al- ways been favorite localities for the hoppers, but in season they are abundant everywhere. They become popular for bait and are in demand just as soon in the summer as they have attained proper size and are in sufficient numbers to be secured in large quantities. This may happen as early as the first week in July ; though usually the anglers will not be using hoppers exclusively until toward the latter part of that month. In 1901, a few anglers began using hoppers as early as July 5, and with good success. On July 7, grasshoppers were heard sing- ing in considerable numbers. August is, however, the best month. It was observed in 1900 and 1903, which were particularly good fishing seasons, that nearly all the good catches made in that month were on grasshoppers. They continue to be used just as long as they can be found, which will ordinarily be until about the last of September or just before the first frosts have come. In 1900 they were in use at least as late as October 1. Several different species are used; the principal one being Melanoplus differentialis, a large red-legged species, abundant in all fields, particularly among ragweeds along the edges of corn- fields. Another species of the same genus, M. bivittatus, is equally good, though somewhat less common. Still another is M. femur- rubrum. Various other species are used ; indeed, almost any kind of grasshopper appeals more or less strongly to most of our fresh- water spiny-rayed game fishes. In September and October when it is difficult to get grasshop- pers, black crickets (of the genus Gryllus) make good bait, par- ticularly for bluegills. Katydids of various species (particularly -Pterophylla camelli- folia and Neoconocephalus robustus) are common. They were first heard singing July 23. From then on they could be heard every favorable night. In 1900 we became especially interested in a particularly musi- cal, broad-winged katydid (Pterophylla camellifolia) that took up its station in a large white oak tree near our cottage. We first took note of it on the evening of July 23. From that date on it was heard on every suitable quiet night until September 27 when it missed although the night was a favorable one. The next night it was heard again and it continued noisy nearly every night for more than three weeks. About the 18th of October its song began to Lake Maxinkuckee, Physical and Biological Survey 29 weaken, particularly on the coolest nights, when it would give only a few very weak calls, usually consisting of "she did" ; sometimes of "she did, she did," slow, deliberate, and weak. On the night of October 24 we heard a single low, weak, slowly uttered "she did," after which it became quiet and we heard it no more. Crickets, especially the common black field cricket (Gryllus as- similis lactuosus) , were fairly common and musical, especially in the fall. Our notebooks have many records of their singing, the earliest entry being May 17. From then on they were heard almost nightly and often in the daytime, until November 22. Mole crickets (Gryllotalpa) are rather common about the lake. Their burrows may be often seen in the sandy beaches. Their interesting musical note can often be heard, especially in August. Tree crickets were abundant, especially in low copses and thickets and, more than anything else except perhaps the katydids, made the autumn nights musical. The following species of Orthoptera have been identified as oc- curring about Lake Maxinkuckee : Diapheromera femorata Say Chorthippns curtipennis Harr. Dissosteira Carolina Linn. Melanoplus atlanis Riley Melanoplus bivittatus Say Melanoplus differentialis Thomas Melanoplus femur-rubrum DeG. Melanoplus fasciatus (Barnston-Walker) Scudderia curvicauda DeG. Pterophylla camelli folia Fabr. Neoconocephalus robustus Scudd. Gryllus assimilis lactuosus Serv. ORDER HEMIPTERA BUGS, CICADAS, APHIDS, AND SCALE INSECTS Of all the groups of insects found in the lake and in the immedi- ate vicinity, the least attention was paid to the Hemiptera or bugs. In the course of seining, raking weeds, taking plankton, etc., vari- ous forms would attract the attention either because of form, color, habit or abundance, and these would be preserved for identification. The Water Boatman, Corisa (Arctocorisa) interrupta Say, ap- pears in our collection and was probably common in the lake. We have no special notes concerning it. 30 Lake Maxinkuckee, Physical and Biological Survey The Back Swimmers, Notonectidse, are represented by Noto- necta undulata Say, obtained November 25, 1904, in the outlet of •Lost Lake, and N. irrorata Uhl., but we have no special notes. The Water Scorpion, Ranatra fusca P. Beauvois, attracted at- tention by its commonness, and by the fact that it was usually in evidence while one was collecting minnows and darters out of the seine. The queer egg cases, laid in rows in bits of floating sticks or rushes, with the two long white setae projecting, had aroused considerable curiosity which was not satisfied until a Ranatra was seen ovipositing in Lake Phalen, Minnesota, in 1907. The Giant Water-bug or "Electric-light Bug" was occasionally seen. On December 7, 1906, one was observed creeping along on the under side of the clear ice, and on October 1, 1904, one was noted in the water near the Monninger cottage. Its smaller rela- tive, Belostoma flumineum Say, was common in the lake and at- tracted attention through the habit of the male of carrying the eggs about on his back. It was obtained in various parts of the lake, in Aubeenaubee Bay, Aubeenaubee Creek, in Culver Inlet, and Lost Lake. On August 6, 1906, the young were observed hatching, the larvse showing red eyes. These bugs as found in the lake are generally infested, sometimes pretty badly, with sac- like red objects attached to them, the young of one of the water- mites. On August 1, 1906, one was found in Lost Lake that had just moulted. Peculiar toad-shaped bugs, Gelostocoris oculatus, were abundant along the sandy shore on the east side of the lake. Some were collected August 6, 1906. The common water-strider Gerris (Hygrotrechus) remigis Say, was common in the creek in Overmeyer's woods and in various pools in the region about the lake. The thread-legged bugs were represented by the long legged Emesa, Emesa longipes, which was very abundant in the Arling- ton waiting-room on one occasion, the insects looking a great deal like walking-sticks and presenting an odd appearance when in flight. Individually by far the most abundant bug noted in the region was the Lace Bug, Corythucha ciliata Say, which was almost al- ways present — both old and young — on the underside of the syca- more leaves. They ate the green color cells from the leaves, leav- ing them an unattractive sickly white in color. Under magnifica- tion these are the most attractive and dainty of the insects, the whole creature resembling a frosty lace. Lake Maxinkuckee, Physical and Biological Survey 31 Among the more common, homely bugs, the most abundant species was Oncopeltus fasciatus Dall, on the milkweed blossoms. Cicadas, or harvest flies, were conspicuous by their absence. Throughout Indiana, as in other parts of the country, one of the characteristic sounds of summer is that of the Dog-day Locust or Harvest Fly. We have no record of hearing it at the lake. It is possible that it does not like the sandy soil. An odd-shaped tree hopper, Enchenopa binotata, was noted in abundance laying white eggs in masses on twigs of the hop tree, Ptelea trifoliata, August 10, 1906, and examples were collected. Plant lice were abundant on the pondweed leaves (Potamogeton natans) in Lost Lake, making a messy looking mass. They were also present, but in fewer numbers, on the water-lily leaves. ORDER TRICHOPTERA THE CADDIS-FLIES The Caddis-flies are among the most interesting of our insects. Although about 150 species have been described from America, there are doubtless many remaining undescribed. The adults are not well known to the general public, in spite of the fact that at times they appear in myriads. The larvae, which are aquatic, are much better known. Every one who has spent any time along mountain streams, or even about other streams, or lakes, if at all observing, can not fail to have noticed the cleverly built, often beautiful, cases which these larvae build of sand, brightly colored pebbles or bits of wood, held together by silken threads. As Professor Kellogg has well said: There is a great variety in the materials used and in the size and shape of the cases, each kind of Caddis-worm having a particular and constant style of housebuilding. Grains of sand may be fastened together to form tiny, smooth-walled, symmetrical cornucopias, or small stones to form larger, rough- walled, irregular cylinders. Small bits of twigs or pine-needles may be used; and these chips may be laid longitudinally or transversely and with projecting ends. Small snail shells or bits of leaves and grass serve for building mate- rials. One kind of Caddis-worm makes a small, coiled case which so much resembles a snail shell that it has actually been described as a shell by con- chologists. * * * An English student removed a Caddis-worm from its case, and provided it with small bits of clear mica, hoping it would build a case of transparent walls. This it really did, and inside its glass house the behavior of the Caddis-worm at home was observed. Most Caddis-worm cases are free and can be carried about by the worm as it wishes, but many of them are fastened to rocks, stones or other objects in the bottom of the stream or lake. When a 32 Lake Maxinkuckee, Physical and Biological Survey Caddis-worm is ready to pupate, the pupa comes out from the submerged case, crawls up on some support above the water and there moults, the winged adult (imago) soon flying away. Some kinds, however, emerge in the water. The Caddis-flies do not feed and are short-lived. They lay their eggs in or near the water where they hatch into Caddis- worms, thus completing the life cycle. We find among our field notes the following: October 29, 1900, collected a number of leathery caddis-cases at the Weedpatch. They were made of bits of shell fastened to- gether. The larva sticks four legs out of the orifice and is able to crawl about freely. February 11, 1901, Caddis larvae noted. June 10, Caddis-flies looking like small white moths, also lace flies, flut- tering in the open woods, making a continuous hum through the night. June 11, noticed ovipositing in the lake; water full of larvae casts, especially early in the morning; Caddis-flies very glaucous, looking like moths at a distance; they stay among the trees in the shady woods; collected a number and observed that their antennae were very long. June 12, about 4 p. m., a strong southwest wind blew great myriads of Caddis-flies toward the lake ; the swarm was thick and white and the appearance was that of a brisk snowstorm. June 13, while passing a maple tree on Long Point in the morning, an immense swarm of Caddis-flies came out of it, flying with a peculiar helpless, half-falling flight. June 14 to 17, many Caddis-flies and midges observed. June 22, caddis- flies laying in the water. October 18 to 29 (1904), Caddis cases (Helicopsyche?) like small snail shells, very abundant, attached to rocks and on bottom in Outlet Bay near Holbrunner's, and along the east side of Long Point. Also a number of empty chim- ney-shaped cases were seen, and several flattish ones moving about making burrows in the sandy bottom near Holbrunner's. October 5 and 10, many fine examples of Helicopsyche on stones, etc., in shallow water near shore. July 27, collected three of a scute-like kind while screening sand ; put them in a saucer of water but they soon died. One species of Caddis-fly was abundant, a frail, glauc- ous, moth-like insect, the leathery cases of which were abundant on the stems of Potamogeton, Scirpus, etc., from midsummer until in the spring when (about June 10) they emerge in great num- bers, and the next day are busy ovipositing. A peculiar case look- ing like a snail shell built of pebbles was found in numbers in the same place. The caddis-cases that attracted the most interest were the flat Lake Maxinkuckee, Physical and Biological Survey 33 ones referred to above, found near shore in sandy bottom along the east shore of Long Point. Just as one species of Caddis-worm builds a case resembling a snail shell, the case of these bears some resemblance to a limpet, or to a marine genus of mollusks, Crepi- dula, showing how similar conditions of life lead to similarity of form. The caddis-case under discussion is very effectively con- cealed by its resemblance to the sand on which it is found; most were found while screening sand in the search for young mussels. The central portion of the shell — that is the first part built — is composed of very minute sand grains; around the margin, either because the larva has become stronger and can handle coarser ma- terial, or because they build up more rapidly, coarser bits are used. When the builder has chosen one sort of material it appears to make some effort to match it. In some cases the valves of the shells of a very small bivalve mollusk, Pisidium, were used around the margins and the cases thus built were especially attractive. The larva lived in a little arch or compartment below the roof of the case. ORDER COLEOPTERA THE BEETLES No special attention was given to the beetles except a few species found in and about the water. No one could help noticing the tiger beetles which were present in considerable swarms on sandy beaches and were conspicuous on hot days, hopping or jump- ing before one walking along shore. There were two kinds pres- ent, a brown one and a bright, metallic green. Whirligig beetles, Dineutes, were common about the edges of the lake. Some were seen swimming about as late as November 4. The Predaceous Diving Beetles (Dytiscus) were not especially common in the lake. We obtained, however, an example of D. hybridus. The water-scavenger, Hydrophilus, appeared more common in pools and ponds than in the lake itself. The egg cases were com- mon on the under sides of the thallus of Riccia. Small hemispherical or rather oval red beetles with black spots (Melasoma interrupta) were exceedingly abundant on the willows along shore early in the spring of 1901. The adults laid the eggs on the leaves of the willows and the young which soon hatched almost defoliated the trees, and the water of the lake was almost covered with the adult beetles. The "water penny", the larva of Psephenus lecontei, was com- mon under pebbles in the lake, its chiton-like form arousing con- 3— 17618— Vol. 2 34 Lake Maxinkuckee, Physical and Biological Survey siderable interest. The most interesting of the beetles in the lake is a little creature belonging to the genus Stenelmis that lives in the masses of lime or rnarl or algae which grow on the exposed ends of the freshwater mussels living in the lake. This growth or deposit is most marked on the shells of Lampsilis luteola which is the most abundant species of mussel in the lake. These mussels burrow more or less in the mud or sand, leaving usually one-tenth to one-fifth of the posterior end exposed to the water. Upon this exposed portion a mass of lime and algse slowly accumulates and finally becomes one-fourth to one-half inch thick. In this mass the little beetle, recently described as new by Professor W. S. Blatchley from collections made by us and named by him Stenelmis sulcatus, is quite common; a collection of 20 to 30 mussels would furnish 50 to 100 examples of the species. Specimens have been found in similar masses on rocks in the lake, and it probably occurs on other species of mussels though we have found none on any except Lampsilis luteola. Click-beetles, especially the large conspicuous eyed Elater, Alaus oculatus, were seen occasionally. The beautifully phosphorescent larva of one was obtained at night on Long Point June 28, 1901. The fireflies or Lampyrids were exceedingly abundant in low grassy places, flashing everywhere at night. The phosphorescent larvse were abundant in the grass along the Inlet. A few stag-beetles were seen on Long Point. Snout Beetles, especially acorn weevils, were common, and most acorns were attacked. One was seen on an acorn, and a snout- beetle was seen June 7, 1901, with patches of eggs, on the tip of a bulrush. The only species of beetles represented in our collections are the following: Stenelmis sulcatus Blatchley Dytiscus hybridus Aube. Ilybius biguttulus Germ. Acilius f rater nus Harris Tropisternus glaber Herbst. Photuris pennsylvanica DeG. ; larvse. Dineutes sp; larvse. Psephenus lecontei Lee Cicindella sp. Melasoma interrupta Lake Maxinkuckee, Physical and Biological Survey 35 ORDER DIPTERA THE FLIES The genera of dipterous insects found about the lake that pos- sess most interest to us are Chironomus, Culex, and Anopheles. Of these the genus Chironomus is economically the most import- ant. One species occurs at the lake in untold billions. Late in September and early in October, 1913, one large yellowish, mos- quito-like species of Chironomus appeared in immense numbers. They were noted every evening at least from September 21 to October 5, filling the air at Long Point from near the surface to a height of 20 or 30 feet, and making it musical with their incessant humming. They were particularly abundant on the evening of October 5. They appeared in enormous numbers sometime before dark and continued late in the night. They literally filled the air; a person could not walk about without being annoyed by their striking him in the face. It was evidently their nuptial flight, and was kept up for about two weeks during warm quiet evenings. The flight would usually begin an hour or so before dusk and con- tinue well into the night. They were in evidence in some numbers throughout the day, but the great flights always occurred late in the evening. Various species of birds were observed feeding upon these insects, among them nighthawks, yellow-billed cuckoos, red- headed woodpeckers, yellow-rumped warblers, and song sparrows. The cuckoos, warblers, swallows and sparrows would pick them from the limbs of trees, while the others took them on the wing. At the same time, vast quantities of the cast-off skins of the larvae of these insects were washed up on shore where they could be seen in great masses along the edge of the water. There they were fed upon by Wilson's snipes, sandpipers, rusty blackbirds and even red-winged blackbirds. They were also fed upon by various fishes such as straw-colored minnows, grayback, top-minnows and the like. The larvae, known as red worms, are very abundant in all parts of the lake; they have been dredged up from even the deepest parts. They are choice food for the fishes and no doubt constitute an important part of the daily menu of the suckers, min- nows, darters, sunfishes and the young of the basses and other spiny-rayed fishes. A 75-pound buffalo-fish contained almost a bucketful of Chironomus larvae. About the middle of August, 1906, a mass of eggs of a smaller species of Chironomus was found and placed in a saucer. The eggs hatched in a few days into little wrigglers which soon became worm-like and built for themselves little tubes in which they 36 Lake Maxinkuckee, Physical and Biological Survey stayed. The tubes varied greatly in size and were probably built up of the excreta of the wrigglers. These wrigglers would some- times leave their tubes and swim about near the surface, and fed greedily upon Spirogyra which was put in the dish. Chironomus larvaB were observed to be abundant throughout the lake during the winter. They were easily obtained by dredging. They were either naked or enclosed in gray mud cases. When naked their bright colors made them very conspicuous. Some that were placed in a jar with some sticklebacks proved very attractive to the latter which snapped them up greedily. Some naked larvae placed in a tumbler of dirty water ever night encased themselves. Another group of dipterous insects of importance is that of the mosquitoes. Fortunately for the summer cottagers, however, mos- quitoes rarely appear in sufficient numbers about the lake to be much of a pest. While there are several marshy tracts near the lake which furnish favorable breeding grounds for mosquitoes, they are, in most instances, sufficiently remote from the cottages, or else the winds are favorable for keeping them away. They are, of course, more common in some seasons than in others. Our notes speak of them as common in certain places November 2, 1902 and 1903, July 3, 1904, September 12, 1907, and September 2, 1913. They are said to have been rather bad during the summer of 1913. Unfortunately, very little attention was given to preserving speci- mens of the various species of insects and our collection contains but three species of mosquitoes, viz : Anopheles quadrimaculata, Culex stimulans and Culex excrucians. Doubtless others occur. Corethra larvas are common in the lake, descending into the deeper waters; they are also common in the woodland ponds. Following is a list of the species of Diptera represented in our collections from Lake Maxinkuckee: Psorophora ciiiata Fabr. Anopheles quadrimaculata Say Culex stimulans Walk. Culex excrucians Walk. T any pus monilis Linn. Calliphora erythrocephala Meig; larvae. Chironomus meridionalis Johan. Chironomus decorus Johan. Chironomus cayugse Johan. Tipulid, probably the genus Tipula. Tanytarsus dives. Ablabcsmyia monilis Linn. Lake Maxinkuckee, Physical and Biological Survey 37 It is worthy of note that the deer-fly, Chrysops, which we found very annoying at Twin Lakes a few miles north, is not common at Lake Maxinkuckee. At Twin Lakes where the deer-flies were par- ticularly pestiferous on one occasion a robber-fly came along and caught one just about to bite. ORDER LEPIDOPTERA BUTTERFLIES AND MOTHS Butterflies are abundant about the lake. The great diversity of soil, moisture, and vegetation, furnishes conditions very favor- able to the development of this group of insects. The number of species is therefore large, and many of them are represented by numerous individuals during their season. Perhaps the most conspicuous species and one that may be seen throughout the greatest number of months is the milkweed but- terfly (Danaus archippus) . Although not the first to appear in the spring it nevertheless appears quite early, and it is the species that may be seen in numbers quite late in the fall. Only a small amount of sunshine and warmth is sufficient to entice it to wing, and single individuals and often groups of three or more may be seen on almost any warm day until late in October or even in No- vember. It is usually most in evidence, however, during the middle of summer (July and August) when the common milkweed (Asclepias syriaca) is in flower. Then about every clump of this showy plant, so abundant along the railroad and on the borders of woods, old fields and ill-kept fence rows, these large butterflies of rich brown and black may be seen in abundance. Late in the fall, even after the first biting frosts have changed the marshes and byways from their summer green to the somber browns and grays of late autumn, several of these butterflies may be seen by any one who goes afield on the still Indian summer days. Sometimes remarkable flights of the Milkweed Butterfly occur. Such a flight was witnessed at noon on September 24, 1907, when several hundred were seen flying from the direction of the lake over Arlington station and into Green's woods. They flew against a strong wind but were able to make good headway. Some of them were much higher than the telegraph poles, others were lower down and sailed upward against the wind. At times only two or three would be in sight, then 20 to 30 would come flying close together. The flight continued for 15 or 20 minutes. The common Cabbage Butterfly (Pieris rapte) is, of course, an 38 Lake Maxinkuckee, Physical and Biological Survey abundant species. Our notes record it at various dates from April 27 to September 27. The larva? are abundant and doubtless often drop or wash into the lake. On October 9 and 10, 1907, the caterpillars of the Cabbage But- terfly were crawling thickly over the east side of a house on Long Point and pupating. Many were dead. They had apparently been stung by ichneumon flies, many of which were seen near the un- affected ones. Beside the dead caterpillars were clusters of golden silky cocoons, about 18 in number, probably of ichneumon-flies. The Southern Cabbage Butterfly (Pieris protodice) is also com- mon. It was noted throughout the season from June 11 to Octo- ber 31. The earliest species to appear in the spring is the beautiful Mourning Cloak (Aglais antiopa) . As it hibernates through the winter it may be seen quite early in the spring when the first warm days revive and bring it forth. Our earliest record is for April 10, but it doubtless appears before then. Our latest record is on October 30, when one was seen hidden under a hollow log. On April 26, three were seen on flowers of Bebb's willow. The Red Admiral (Vanessa atalanta) is another pretty species which appears early in the spring and remains until late in the fall. Our early and late dates are June 7 and October 29. This species is fairly common. Hunter's butterfly (Vanessa virginiensis) is another beautiful but less common species which we have noted from May 3 to Octo- ber 29. The genus Polygonia is represented by at least two species (Polygonia comma and Polygonia interrogation's}. These are also among the species which appear early in the spring and re- main later in the fall. They are solitary in their habits ; not often are more than one or two seen together. Our notes mention Poly- gonias at various times from April 4 to November 2. Of the swallowtail butterflies perhaps the most common is the Black Swallowtail (Papilio troilus). Our records mention it on various dates from May 9 to September 27. The zebra or Ajax Swallowtail (Papilio marcellus) and the large yellow swallowtail (Papilio glaucus f. turnus) are apparently not common. The following is a list of the species of butterflies noted at Lake Maxinkuckee: 1. Papilio polyxenes Fabr. 2. Papilio troilus Linn. 3. Papilio marcellus Cram. Lake Maxinkuckee, Physical and Biological Survey 39 4. Pieris protodice Bd.-Lec. 5. Pieris rapse Linn. 6. Eurymus philodice Godt. 7. Eurema euterpe Men. 8. Danaus archippus Fabr. 9. Cissa eurytus Fabr. 10. Satyrodes canthus Linn. 11. Cercyonis alope Fabr. 12. Cercyonis alope Fabr. var. 13. Cercyonis alope nephele Kirby 14. Argynnis cybele Fabr. 15. Brenthis myrina Cram. 16. Phyciodes tharos Drury 17. Polygonia interrogationis Fabr. 18. Polygonia comma Harr. 19. Aglais antiopa Linn. 20. Vanessa atalanta Linn. 21. Vanessa virginiensis Drury 22. Basilarchia archippus Cram. 23. Libythea bachmani Kirt. 24. Heodes hypophlseas Boisd. 25. Heodes theo Boisd. 26. Everes comyntas Godt. 27. Lycsenopsis pseudargiolus Bd.-Lec. 28. Epargyreus tityrus Fabr. 29. Cocceius pylades Scud. 30. Pyrgus tessellata Scud. 31. Thanaos persius Scud. 32. Ancyloxypha numitor Fabr. 33. Callosamia promethea Drury (moth) 34. Scepsis fulvicollis Hubn. (moth) 35. Enbaphe ferruginosa Walk, (moth) 36. Utetheisa bella Linn, (moth) 37. Xanthotype crocataria Fabr. (moth) ORDER HYMENOPTERA THE BEES Our notes on the Hymenoptera are very few indeed. These, the most highly organized of insects, have the least to do with aquatic life. Judging from the number and kinds of oak galls on the trees 40 Lake Maxinkuckee, Physical and Biological Survey about the lake, gall-wasps are abundant and represented by various species. Of the Braconids, Microgaster is common, and the parasitized caterpillars that have fallen a prey to it have been frequently found about the lake. Ants are not so common as to be a nuisance. There are, how- ever, a few large dome-shaped ant hills along the border of the wet ground near Lost Lake and along its outlet down by Walley's woods. The solitary wasps are represented by the potter- wasp, Eumenes fraterna, which builds its exquisite little clay vases on slender twigs down at the edges of the woods toward the south end of th'e lake. Wasps and Yellowjackets are occasionally seen. Hornet's nests were rather rare. On November 2, 1902 a big hornet's nest was seen in a white oak in Walley's woods 30 feet up. It had been shot into. Another very large nest was found October 24, 1907 beside a lane west of the ice-houses near the tamarack swamp. It was built on some wild-cherry sprouts, the nest almost or quite touching the ground. Some one had torn away a part of one side. Tearing the nest open it was found that many of the grubs were just emerging and crawling about. A photo was taken of the nest. Dr. L. O. Howard says that this hatching in the fall is very unusual. There is a current popular belief that if hornets build their nests high in the trees it is a sign of an open winter,, while if they are built close to the ground the winter will be severe. On October 11, 1913, a fine large nest was seen in a tulip tree in Overmeyer's woods, south of Farrar's. It was on the end of a limb about 20 feet from the ground. Our notes have occasional references to both bumblebees and honey bees. There is little bee-keeping about the lake (we saw a few hives on the east side) though the country with its moist low- lands covered with blossoms from early spring to late autumn would furnish excellent opportunities. Lake Maxinkuckee, Physical and Biological Survey 41 THE MOLLUSKS THE During the study of Lake Maxinkuckee considerable attention was given to the mollusks, particularly the freshwater mussels or Unionidse. This was justified by the rapid and astonishing de- velopment of the pearl button industry in America which is de- pendent upon the shells of mussels for its raw material. The recent discovery by Lefevre and Curtis of methods whereby com- mercially valuable species of mussels are now successfully propa- gated artificially, adds special interest to these mollusks. Recent studies and discoveries relating to the formation and artificial pro- duction of pearls in freshwater mussels may also be mentioned as showing the importance of careful study of the taxonomy and life history of the UnionidaB. LAKES AND PONDS AS THE HOME OF MUSSELS Generally speaking, lakes and ponds are not so well suited to the growth and development of mussels as rivers are; the species of lake or pond mussels are comparatively few, and the individuals usually somewhat dwarfed. Of about 84 species of mussels re- ported for the State of Indiana, only about 24 are found in lakes, not all of these in any one lake, and several of them but rarely in any. Of the 24 species occasionally found in lakes, but five are reported only in lakes, and only three or four of the species com- mon to both lakes and rivers seem to prefer lakes. In rivers, the essential feature favorable to the development of mussels is the current; and in the rivers the mussel beds reach their best development in the riffles, where the current is strong- est. The importance of the current to the well-being of the mussels is indicated by the position these mollusks naturally as- sume in the beds, the inhalent and exhalent apertures of the crea- tures being directed up-stream against the current.. The im- portance of the current is not merely as a bringer of food ; exam- inations show that the mussels of the plankton-rich lakes and ponds usually contain more food material than those of rivers. The current gives the river-mussels the advantage of a constant change of water, which means a more abundant supply of oxygen, and doubtless a more varied supply of mineral matter, from the various sorts of soil through which the river flows. The current is also probably of considerable importance in as- sisting in the fertilization of mussels, one of its functions being 42 Lake Maxinkuckee, Physical and Biological Survey m the conveyance of sperm from mussels in upper portions of the bed to other mussels below. In places where there is no current, fertilization must be more largely a matter of chance. Although the majority of species of mussels prefer a river where there is a good current, some are more fitted to the quieter parts of streams, or to ponds. These are chiefly thin-shelled spec- ies with weakly developed or undeveloped hinge-teeth, best repre- sented by the genus Anodonta. In some places Anodontas are known as pond-mussels, as distinguished from the heavier sorts or river-mussels. The distinction between lakes and rivers is not constant in de- gree; we have all sorts of gradations from the extreme form of lake — isolated bodies without outlet — through lakes with relatively large, important outlets, to such lakes as are simply expansions of a river-bed, examples of the latter type being Lake Pepin, Minn., of the upper Mississippi, and the former English Lake in Indiana, an expansion of the Kankakee. As a usual thing, the more fluvia- tile a lake is, or the larger and more river-like its outlet, the more river-like will be its mussel fauna, both in abundance and species. In such lakes the mussels retain a vital continuity with the mussel beds of the river. In the- less fluviatile lakes the mussels are more isolated, and there is more inbreeding. The large number (24) of lake-dwelling species recorded for Indiana is due to the fact that some of the lakes of Indiana are more or less fluviatile, and contain several species of river shells. * ORIGIN AND CHARACTER OF THE MAXINKUCKEE MUSSELS Lake Maxinkuckee, having a long, narrow, winding and rela- tively unimportant outlet, is a representative of one of the less fluviatile types of lakes, forming a pretty well marked contrast to the various lakes cited above, and bearing a pretty close resem- blance to the neighboring lakes, such as Twin Lakes, Pretty Lake, Bass Lake, etc. The Maxinkuckee mussels are doubtless derived from an- cestors brought up the Outlet from the Tippecanoe River by as- cending fishes. It is doubtful whether any have been introduced by the numerous plants of fish in the lake, though such a thing is possible. During the various times the lake was visited, a few Tippecanoe River mussels were planted in the thoroughfare be- tween the lakes, and a few Yellow River and Kankakee mussels were planted in the main lake. The Outlet of Lake Maxinkuckee is now a narrow, shallow winding stream, straightened in places by ditching, and bordered Lake Maxinkuckee, Physical and Biological Survey 43 on each side by a flat sedgy plain which indicates the former breadth and importance of the stream. The colonization of the lake with mussels was probably effected chiefly during the period when the Outlet was a broad and relatively important stream. The situation has been carefully considered and seems to show that the mussels of the river and lake are isolated from each other and that there is no longer any vital connection between them. The strongest indication of the independence of the lake and river mussel faunas is the appearance of the Maxinkuckee mussels them- selves; these are lake-mussels, easily distinguished for the most part from river mussels of the same species, and many of them are ditinguishable also from the mussels of the neighboring lakes. The Tippecanoe River is fairly well supplied with mussels. Al- though the number of species is considerably fewer, and the size of the individuals is generally smaller, than that of the Wabash into which it flows, it compares very favorably with rivers of its size. At Belong, Ind., a short distance above the mouth of the Outlet of Lake Maxinkuckee, were obtained in one bed specimens representing 24 species of mussels or about twice the number of kinds found in Lake Maxinkuckee. • Our knowledge of the extent and importance of migrations of fishes from the Tippecanoe River up to the lake and from the lake down to the river — a question which has a marked bearing upon the relationship of the mussel faunas — is not as complete as it should be, but indications are that they are not important or ex- tensive. Inasmuch as the geographic distribution of a given species of mussel is coextensive with that of the species of fish which serves as its host, this question is worthy of careful consider- ation. There are several species of fishes of the Tippecanoe River (Etheostoma camurum, Hadropterus evides, Hybopsis amblops, etc.) which were not -found either in the Outlet or in the lakes, and other species (Hadropterus aspro, Ericymba buccata, Diplesion blennioides) which have pushed halfway up the Outlet, but were found no further up. In this connection, the mussel fauna of the Outlet is worthy of consideration, and on various occasions, but especially on a trip down the 6utlet September 30, 1907, particular attention was paid to this feature. The Outlet is not particularly well suited to the life and growth of mussels; the bottom is either a firm peaty soil or fine shifting sand; moreover, the course has been artificially changed in some places and the stream has naturally shortened its length in others by making cutoffs. In addition to this the mussel fauna of such 44 Lake Maxinkuckee, Physical and Biological Survey a narrow shallow stream would be the prey of muskrats, minks, etc., the entire length and width of the beds. On the trip mentioned above, about a mile below Lost Lake a fine example of Lampsilis iris was found. This is the farthest up stream any species of mussel was obtained, and as this species is fairly common in both lakes and abundant in the Tippecanoe River, we have here the nearest approach to a continuous fauna. Some dead shells but no living examples of Quadrula undulata were found a little farther down. Farther down stream, from a quarter to half a mile, a short distance above the second cross-road south of the lake, was found a small mussel-bed of about 40 or 50 mussels, the great majority of which were Quadrula undulata. A few liv- ing Lampsilis iris, two dead Symphynota compressa, one living Symphynota costata (gravid), and a few dead shells of Quadrula coccinea, complete the list. Below this point no mussels were found until near where the Outlet joins the Tippecanoe. Here, a few rods up the Outlet, a fair bed of Quadrula coccinea was found. Of the five species of mussel found in the Outlet, only two, L. iris and Q. coccinea, are found in the lake, the latter but rarely. The form and general appearance of the Q. undulata of the Outlet is quite peculiar and they can be picked out at once in collections from the various rivers of the country. They are unusually elon- gate, in this respect representing some of the Tippecanoe mussels but differing from them in being thinner, and in having the fur- rows between the plicae unusually deep and sharp. The costaB on the postero-dorsal slope are very marked, and the epidermis jet black. The umbones are considerably eroded. DISTRIBUTION OF MUSSELS IN THE LAKE In rivers, where there is a great variety of conditions, such as differences of current, bottom, etc., one finds .the different species of mussels inhabiting different localities and different situations. In the lakes, where we have comparatively few species of mussels and not such important differences of environment, the distribu- tion of the various species is much the same. The same condi- tions, such as rather shallow water and moderately firm bottom, are equally suitable for all. A few important exceptions may be noted ; as for example, the less common species of the lake are often more or less local in distribution. The only well-marked bed of Quadrula rubiginosa in the lakes is in the Lost Lake mussel-bed below the Bardsley cottage, and this is the only place where Lamp- silis subrostrata can be collected in any considerable numbers. Lampsilis glans has a marked preference for the shallow water at Lake Maxinkuckee, Physical and Biological Survey 45 the edge of the thoroughfare between the lakes; occasional ex- amples can, however, be picked up almost anywhere along shore, and it appears to be increasing considerably along shore at Long Point. Anodonta grandis footiana, which can live in softer bottom than the other mussels, has a considerably wider distribution, and was dredged up in deeper water than any of the other mussels. The mussels are to be found almost anywhere in water from 2 to 5 or 6 feet deep where the bottom is more or less sandy or marly. The beds are composed chiefly of the three principal spec- ies of the lake, Lampsilis luteola, Unio gibbosus and Anodonta grandis footiana, with the less common species sparsely inter- spersed. Especially good mussel beds occur at Long Point, along shore by Farrar's and McDonald's, by the Depot grounds, in Aubeenaubee Bay out from the Military Academy, and in the shal- low water just beyond the mouth of Norris Inlet. Mussels are fairly well scattered from Long Point more or less continuously all the way southward to beyond Overmyer's hill, and from a little north of the ice-houses all the way around to the Military Academy. They are quite abundant in the neighborhood of Winfield's in shal- low water, and occur scattered along the east side of the lake a little way out from shore. A good mussel bed is found in Lost Lake along the east shore, extending from a little south of the Bardsley cottage to where the bulrushes and water-lilies grow thickly in the soft black muck near shore. Movements: — Closely connected with the question of distribu- tion is that of movement. The greater number of mussels of the lake, especially in the deeper water, spend their lives in a state of quiescence. Young mussels appear to be more active than older ones. The mussels retain the power of locomotion during all their lives, but after they have got well settled down, they only occa- sionally use this power. The mussels of the shallow water near shore move out into deeper water at the approach of cold weather, in late autumn or early winter, and bury themselves more deeply in the sand. This movement is rather irregular and was not ob- served every year. It was strikingly manifest in the late autumn of 1913, when at one of the piers off Long Point a large number of furrows was observed heading straight into deep water with a mussel at the outer end of each. The return of the mussels to shore during the spring and summer was not observed. Many of them are probably washed shoreward by strong waves of the spring and summer storms, and some are carried shoreward by muskrats and dropped there. Occasional mussels were observed moving about in midwinter — even in rather deep water. During the 46 Lake Maxinkuckee, Physical and Biological Survey winter of 1900-1901 an example of Lampsilis luteola, in rather deep water in the vicinity of Winfield's, was observed to have moved about 18 inches within a few days. Its track could be dis- tinctly seen through the clear ice. As a result of the quiescence of the lake mussels, the posterior half or i of the shell, which projects up from the lake bottom, is usually covered by a thick marly concretion which appears to be a mixture of minute algae and lime. This marly concretion grows concentrically, forming rounded nodules, its development increas- ing with the age and size of the shell. This concretion, though most abundant on shells, is not confined entirely to them, but grows also on rocks that have lain undisturbed on the bottom. When growing on, shells, it adheres to them very closely; and upon being pried loose sometimes separates from them much as the matrix separates from a fossil, and leaves the epidermis of the mussel clean. In other cases it adheres more firmly and is difficult to scrape off clean. On this marly growth, colonies of Ophrydium, much the size, color, and general appearance of grapes with the skins removed, are often found growing, and in the cavities and interstices of the marl, a handsome little water-beetle, Stenelmis undulatus Blatchley, and its peculiar elongate black larva?, live in considerable numbers but apparently have nothing to do with the mussels. Various species of hydrachnids, one of them strikingly handsome with its green body sprinkled with bright red dots, also live in the cavities of the marl, and offer some suggestion as to how the parasitic mite Atax went a step farther and took up its habitation within the mussel itself. Food and feeding: — An examination of the stomach and in- testinal contents of the various species of mussels of the lake showed no noticeable differences between the food of the different species. Enough of the bottom mud is generally present to give the food mass the color of the bottom on which the mussels are found; thus the stomach-contents of the mussels found in the black bottom of Lost Lake was usually blackish, while that of those found in the lighter bottom at Long Point was grayish. In- termixed, however, with the whole mass was always enough algse to give it a somewhat greenish tinge, this green being usually inter- mixed more or less in the form of flakes. A striking contrast be- tween the stomach contents of mussels inhabiting lakes and those found in rivers is the much greater preponderance of organic mat- ter in the food of the lake mussels. The stomach contents of river- mussels is generally chiefly mud, with a few diatoms, desmids, Scenedesmus and Pediastrum intermixed, as said above. Those of Lake Maxinkuckee, Physical and Biological Survey 47 the lake mussels are almost always full enough of algse to be more or less flecked with green and sometimes the whole mass is de- cidedly greenish. On being placed in a vial of preserving fluid (3% formalin was generally used) and shaken, the material from the river mussels always retains the uniform appearance of mud; that from the lake mussels separates, the mud settling to the bot- tom and the organic material settling as a light flocculent mass above the more solid portion. This top layer is composed of the various plankton elements of the lake, and was found to vary con- siderably in different lakes. In the Lake Maxinkuckee mussels it was found to consist chiefly of such species as Microcystis aerugi- nosa, Botryococcus braunii, Coelosphaerium kuetzingianum, various diatoms, such as species of Navicula, Rhoicosphenia, Gomphonema, Cyclotella, and Cocconema, various forms of desmids, especially Cosmarium and Staurastrum, various forms of Scenedesmus, con- siderable Peridinium tablulatum, and short filaments of Lyngbya. Pediastrum, both boryanum and duplex are here, as almost every- where, rather common objects encountered in the intestines of mussels. Casts of the rotifier Anuraea cochlearis, and of the small entomostracan Chydorus, were occasionally encountered. In one of the Lost Lake mussels, Dinobryon, an exceedingly frequent ele- ment of the mussel-food in Lake Amelia, Minn., but rare here, was found. No opportunities were had to study the stomach contents during the winter, the mussel work having not been taken up to any great extent during the earlier part of the survey. Mussels obtained quite late in the autumn contained much the same material as in summer. The open and apparently active inhalent and exhalent apertures noted throughout the winter in some individuals would indicate that the mussels — at least some of them — do not hiber- nate, but carry on life processes more or less actively the year round. The presence of pretty well marked growth-rings would indicate, however, annual rest periods. As diatoms appear to be much more abundant in the water during the winter, it is probable that they enter more plentifully into the mussel's bill-of-fare dur- ing the late autumn, winter and early spring than during the sum- mer. In consideration of the mussels as feeders on plankton ele- ments, it is worth while to investigate whether these are not of benefit to the lake as the reducers of excessive amounts of such undesirable elements as Lyngbya, Anabaena and Microcystis, and whether a considerable increase in the mussel population by means of artificial propagation would not clear up the lake to a consider- able extent. The following studies of stomach contents and table 48 Lake Maxinkuckee, Physical and Biological Survey of mussel food are by no means exhaustive, but represent hurried examinations and a record of the more easily recognized forms out of a mass of doubtful material. They are intended to be simply suggestive. Closely connected with the question of food and nutrition is that of the size of mussels. A marked feature of the mussels of Lake Maxinkuckee as well as of the neighboring lakes, is the dwarfing of many of the species, and this is rather difficult to explain, when one considers the large amount of organic material they ingest. The mussels of a few northern lakes examined were thick-shelled and large, so this dwarfness may not be necessarily associated with lake conditions, that is, absence of current. A possible explana- tion is that of close inbreeding, there being no admixture of new blood with other distant colonies, such as is possible where the lake is in close connection with a large river and its mussel beds. Breeding habits, reproduction, etc.: — The reference to inbreed- ing above leads to a consideration of breeding and breeding habits. At first glance it would appear that lakes, having no or only feeble currents would make fertilization of the ova of the female mussels largely a question of chance. It is not possible, with the data at hand, to make precise comparisons between number of gravid fe- males of the mussels of lakes and rivers during the proper seasons ; but the general impression gained from having examined the mus- sels of numerous lakes and rivers through the different seasons is that there are fewer of the mussels of the lake that succeed in hav- ing their ova fertilized. Gravid mussels are indeed not rare in the lake at the proper seasons, but they seem to be much fewer than one might expect. On October 17, 1907, for example, of 252 Lampsilis luteola examined, 41 were of the characteristic female form but only 25 were gravid. Likewise of 18 Anodontas exam- ined on the same date, only 2 were gravid. This is a considerably lower percentage than one would expect in rivers at that date. There are other indications that the functions of reproduction are much less prominent in the lake than in rivers. In the height of the spawning season certain species of mussels, especially Lamp- silis ventricosa and L. multiradiata, exhibit, in the neighboring rivers, a very striking appearance, due to the excessive develop- ment and high coloration of portions of the mantle near the inhalent aperture. Though both these species are found in the lake, none was observed in this condition. In some rivers in densely crowded beds, moreover, one frequently encounters precocious individuals; small shells, usually apparently only two or three years old but gravid and with the characteristic female contour markedly de- Lake Maxinkuckee, Physical and Biological Survey 49 veloped. This is possibly related to opportunities of fertilization of ova, and is most frequently observed in L. ventricosa and L. luteola; no such precociously developed mussels were found in the lakes. A large and well developed female Lampsilis ventricosa was transplanted from Yellow River into Lake Maxinkuckee. On being examined two years later in the autumn when this species is usually gravid, it was found to be sterile. The natural infection of fishes of the lake with the glochidia of the mussels does not appear to be common. The gills of an im- mense number of fishes were examined for parasites, but no glochidia were noted. Some young bluegill and redeye, exposed to glochidia of L. luteola in the autumn of 1912, took very readily. Very young mussels were either few, or very difficult to find. Diligent search was made for them, especially in the sandy bottom near Long Point, the sand being scooped up and sieved through fine-meshed sieves. Numerous and varied forms of life were thus obtained, such as Sphaerium, Pisidium, caddis-cases, etc., and rather small but by no means minute examples of L. luteola. These young shells were remarkably brightly rayed. Half-grown Q. rubiginosa were fairly common in the beds of Lost Lake. Proportion of various species in the lake: — Of a collection of 340 living mussels collected October 17, 1907, at Long Point, 252 were Lampsilis luteola, 41 L. ventricosa, 21 Unio gibbosus, 18 Anodonta grandis footiana, 5 Strophitus edentulus and 3 Lamp- silis subrostrata. In deep water U. gibbosus and Anodonta would have given a higher percentage, and in the Lost Lake beds Quad- rula rubiginosa would be present in considerable relative abund- ance. Parasites, enemies, and diseases: — As a general rule the mus- sels of lakes, ponds and bayous are more heavily infested with parasites than those of swiftly flowing rivers, the probable rea- son being that in still waters the parasites can migrate more easily from one mussel to another than where there is a swift cur- rent. The mussels of the lake are not nearly so badly parasitized as those of the sloughs of the Mississippi, the dead water in the Maumee above the dams, or those of Twin Lakes a few miles to the north. The parasites will be taken up more fully in consideration of the various species of mussels. Cotylaspis insignis and several species of Atax are the most common parasites. Unlike the mus- sels of most of our rivers, the mussels of the lakes are compara- tively exempt from the ravages of man. A few are killed and used for bait, and now and then a mild case of pearl fever ap- 1 17618— Vol. 2 50 Lake Maxinkuckee, Physical and Biological Survey pears at the lake but is soon cured by the examination of a bushel or two of mussels. On September 22, 1907, a man was seen at the south end of the lake with about a peck of shells which he had opened in a vain search for pearls ; on October 8 of the same year a pile of about a half bushel of shells, which had evidently been opened by pearlers, was found in Overmyer's woods. Another pearler was seen in 1907 who had collected a few slugs of almost no value. One of the citizens of Culver, in 1906, submitted a small vial of lake baroques for valuation, but they had no worth what- ever. The greatest enemy of the lake mussels is the muskrat, and its depredations are for the most part confined to mussels near shore. The muskrat does not usually begin its mussel diet until rather late autumn, when much of the succulent vegetation upon which it feeds has been cut down by frost. Some autumns, how- ever, they begin much earlier than others; a scarcity of vegeta- tion or an abundance of old muskrats may have much to do with this. The rodent usually chooses for its feeding grounds some ob- ject projecting out above the water, such as a pier or the top of a fallen tree. Near or under such objects one occasionally finds large piles of shells. The muskrat apparently has no especial pref- erence for one species of mussel above another, but naturally sub- sists most freely on the most abundant species. These shell piles are excellent places to search for the rarer shells of the lake. On September 24, 1907, about a bushel of shells, recently cleaned out by muskrats, was found at Long Point where a pier had been removed not long before. The shells were all of rather small size and were in about 18 inches of water. About half were taken and examined. Of these shells 358 were Lampsilis luteola, 167 Unio gibbosus, 6 Lampsilis iris, and 1 Lampsilis multiradiata. In the autumn of 1913 freshly opened shells of Lampsilis glans were common along shore at Long Point. The first shells killed are rather small and are probably killed by young muskrats. In the winter after the lake is frozen, great cracks through the ice extend out from shore in various directions, and this enables the muskrat to extend his depredations some distance from shore in definite limited directions. During the winter of 1904 a musk- rat was observed feeding on mussels along the broad ice-crack that extended from the end of Long Point northeastward across the lake. The muskrat was about 500 feet from shore. It repeatedly dived from the edge of the ice-crack, and reappeared with a mussel in its mouth. Upon reaching the surface with its catch, it sat down on its haunches at the edge of the creek, and, holding the mussel in its front feet, pried the valves apart with its teeth and Lake Maxinkuckee, Physical and Biological Survey 51 scooped or licked out the contents of the shell. Some of the larger mussels were too strong for it to open, and a part of these were left lying on the ice. The bottom of the lake near Long Point, and also over by Norris's, is well paved with shells that have been killed by muskrats. Muskrats do not seem to relish the gills of gravid mussels; these parts are occasionally found untouched where the animal had been feeding. LIST OF SPECIES 1. FLAT NIGGERHEAD QUADRULA COCCINEA (Conrad) Rare at the lake; this is a river rather than a lake shell and would be expected in abundance only in fluviatile lakes, or lakes with broad short outlets and vital connection with river faunas. The few living mussels of this species found in the lake probably represent a vanishing remnant of a fauna introduced when the lake had a broader outlet than at present and communication with the river below was more active. A few dead shells were found along the north shore of the lake at various times. On October 25, 1907, a shell 1.75 inches long was found near the railroad bridge at Culver, and in 1909 another small shell was found on the shore at Aubeenaubee Bay. Some fine large examples brought up from the Tippecanoe were planted in the Thoroughfare below the railroad bridge, but they have probably been covered and suffocated by sand. 2. WABASH PIG-TOE QUADRULA RUBIGINOSA (Lea) More common in Lake Maxinkuckee than Q. coccinea, but nev- ertheless rather rare, only a few dwarfed shells having been found. In Lost Lake below the Bardsley cottage it was a fairly common species. None of the shells found was of large size, but all were well-formed and handsome. The older shells are almost jet black and peculiarly elongate, with the umbones markedly an- terior in position. They look considerably unlike those of either the Tippecanoe or Yellow River, but a form much like the Lost Lake shells was found in the lower course of the Kankakee. No gravid examples were found in the lake. Half grown examples are rather common in Lost Lake beds, but as they are usually buried considerably deeper in the sand than the older shells, they are harder to find. These half-grown shells are of a peculiarly beautiful golden yellow color with a satiny epidermis, and are of the same shape as those found in the neighboring rivers — 52 Lake Maxinkuckee, Physical and Biological Survey that is, the normal or usual shape of the species. The peculiar elongate form of the adult is therefore evidently the product of local influences. The young shells are very iridescent and trans- lucent— much more so than those found in rivers. Q. rubiginosa is at its best a very fair button shell, but the lake shells are too small to work up well. This species appears to be rather rare in lakes. The only lake examples of this species with which the Lost Lake shells were compared were some obtained in Lake Erie. The Lake Erie shells were much more dwarfed, but very solid. Food: — The following is the result of an examination of the material found in the intestines of Q. rubiginosa from Lost Lake: Sample 1. August 2, 1908. Mass fine flocculent rather brown- ish green material, cohering somewhat in cylinders. Looks as if chiefly organic; not gritty to touch. Organisms present: Scen- edesmus, Fragilaria, Tetraedron, Navicula, Peridinium tabulatum, Anuraea, and Botryococcus braunii. Sample 2. August 20, 1908. A large amount of material ; ap- pearance in vial, bottom black, top a fine flocculent sediment. In the top material are Teraedron, Scenedesmus, Microcystis aerug- inosa, and many disassociated minute cells. Black bottom com- posed of Anuraea, Lyngbya aestuarii, a long filament; Scenedes- mus, many, Peridinium tabulatum, Tetraedron, Epithemia turgida, Merismopedia, cast of Cyclops, Melosira crenulata, Gloeocapsa, Staurastrum, Pediastrum boryanum, Gomphonema, Chaetophora, Cosmarium, sponge spicule, Gomphospha,eria aponina, 'and Botry- ococcus braunii. Sample 3. August 20, 1908. A small amount of flocculent brownish material. Microcystis aeruginosa, Peridinium tabulatum many and a good many empty cuirasses, Chydorus, Eudorina a few, Scenedesmus common ; Diatoms, Pediastrum duplex. Sample 4. August 20, 1908. Fine blue-green flocculent ma- terial. Lyngbya aestuarii, several filaments; Microcystis aerug- inosa, common ; Coelosphaerium kttetzingianum, Peridinium tabu- latum, very abundant; Chydorus, Anuraea, Botryococcus braunii, Coekistrum, Staurastrum 1, small, Navacula, several. Sample 5. August 20, 1908. Fine bluish-green material. Peridinium tabulatum, abundant; Cymbella cymbiformis, Navi- cula, a few; Anuraea cochlearis, Microcystis aeruginosa, Chydorus 1 entire, and other fragments ; Pediastrum duplex, Coelosphaerium kuetzingmnum; Cosmarium ,- Coscinodiscus, Scenedesmus, very common; Merismopedia glauca. Lake Maxinkuckee, Physical and Biological Survey 53 Sample 6. August 20, 1908. A small amount of flocculent grayish material. Peridinium tabulatum, abundant, agglutinated in masses; Mic- rocystis aeruginosa, very common; Navicula, Staurastrum, Cos- marium, several; Chydorus, fragment; Scenedesmus, small forms, common; Pediastrum boryanum, Cymbella cymbiformis, Tetraed- ron, common; various diatoms; Rotifer, an elongate species; Merismopedia glauca; Coelastrum, desmids. Sample 7. August 21, 1908. A small amount of rather co- herent fine flocculent greenish material. Peridinium tabulatum, very common; Anuraea cochlearis, a few; Microcystis aeruginosa, frequent; Lyngbya aestuarii, short filament; Pediastrum boryanum, diatoms (Cymbella cymbi- formis; Cymatopleura; Epithemia argus, Gomphonema, Synedra) Tetraedron, Scenedesmus, occasional; Dinobryon, Staurastrum, rather slender form. Sample 8. August 20, 1908. A small amount of flocculent bluish-gray material. Peridinium tabulatum, most abundant; Coelosphaerium kuetz- ingianum; Pediastrum duplex; Microcystis aeruginosa, Anuraea cochlearis, sponge spicule, diatoms (Navicula, Cymbella, etc.), Scenedesmus. Sample 9. August 20, 1908; a fair amount of flocculent gray- ish-brown material with a greenish cast. Peridinium tabulatum, most abundant; Microcystis aeruginosa, Anuraea cochlearis, Stofiirastrum, Pediastrum duplex, Botryococ- cus braunii; Tetraedron minimum, Coelosphaerium kuetzing- ianum; Pediastrumi boryanum, Chydorus, Lyngbya aestuarii, Gloeocapsa, diatoms — Cymbella cymbiformis, Navicula. 3. SPIKE UNIO GIBBOSUS Barnes This mussel, known among clammers as the "spike" or "lady- finger" is, next to Lampsilis luteola, the most abundant shell in the lake. It is found wherever the other mussels are; that is, in sandy or somewhat marly bottom in rather shallow water most of the way around the lake, and in the shell-bed in Lost Lake below Bardsley's. In Lake Maxinkuckee one of the best beds is at Long Point. It is abundant also at Norris Inlet, and by McDonald's and Farrar's. No very young of this species were found in the lake ; they are, however, hard to find in numbers anywhere, even in rivers where 54 Lake Maxinkuckee, Physical and Biological Survey the species is abundant, except in cases where portions of the river go almost dry, and this of course never happens to the beds in the lake. The half-grown examples are solid, rather cylindrical shells, the same neat form that is known as the "spike" among the clam- mers. The old shells develop into a peculiar form, being flattened, arcuate along the ventral border and very thin posteriorly, so that they usually crack badly in drying; they represent the form de- scribed by Simpson as var. delicata. In general outline they re- mind one somewhat of Margaritana monodonta. This form is not strictly confined to the lake; some similar shells were collected in the Wabash near Terre Haute. As found in the lake, Unio gibbosus is very constant in its char- acters, the only noteworthy difference between individuals being the change in shape already referred to as being due to age. In rivers this shell exhibits considerable variation in shape, size, color of nacre, etc., but the shells of the lake are quite constant in almost every respect. The nacre is a deep purple, never varying to pink or white as it frequently does in rivers. Like Lampsilis luteola this species is frequently preyed upon by muskrats and the cleaned out shells are common where these ro- dents have had their feasts. Although U. gibbosus of the Tippecanoe River near the mouth of the Outlet is very commonly infested with a distomid parasite along the hinge-line which brings about the formation of irregular baroques, this parasite does not occur in the lake so far as known. Small species of Atax are common parasites of this species in the lake, and in 1909 one was found affected by the large Atax ing ens. Even the large strong river shells of Unio gibbosus have no value in the manufacture of buttoms because of their purple color and lack of luster. (The white-nacred shells are sometimes used.) The only other lake examples with which the Lake Maxinkuckee specimens of this species have been compared, are some collected in Lake Erie at Put-in-Bay. The Lake Erie shells are much unlike the Maxinkuckee specimens, being short, humped and remarkably solid and heavy. Similar shells to those of Lake Erie are found in some of the small southern rivers. We have no notes referring to gravid examples in the lake. This was probably because the most active work in collecting and examining mussels was carried on in the autumn, and the breeding period of this species is in early summer. Lake Maxinkuckee, Physical and Biological Survey 55 4. ALASMIDONTA CALCEOLUS (Lea) Judging from the dead shells found scattered along shore, this is not a particularly rare species in the lake. The shells were found most abundantly along the north shore of the lake, although they were also found along the east and southeast portion and were not infrequent between Arlington and Long Point. No living examples were found. On account of its small size and its habits this is a rather difficult species to find, even where common, ex- cept under favorable conditions such as exceptionally low water, when the mussels move about more or less. Nothing was therefore learned of its habits in the lake. In the Tippecanoe River near De- long, Ind., this species was rather common in stiff blue clay near shore, and it is fairly abundant in Yellow River at Plymouth. Here, although the dead shells were common, the living examples were difficult to find until, during a period of very low water, they began actively moving about and could be tracked down. The species, which reaches an unusually large size in Yellow River, was there found gravid in autumn (September and October). The glochidia are of the Anodonta type, chestnut-shaped or rounded- triangular in outline, with large hooks at the ventral tips of the valves. 5. FLOATER ANODONTA GRANDIS FOOTIANA Lea Although the genus Anodonta is generally regarded as the "Pond-mussel" par excellence, the species of which might natur- ally be expected to be at home in lakes and ponds and thrive in such places even better than in rivers, the Anodontas of Lake Max- inkuckee show, along with the river-species proper, the dwarfing influence of the lake. Moreover, Anodonta is not, as one might naturally expect, the most abundant mussel in the lake, but is out- numbered in some beds at least, by both Lampsilis luteola and Unio gibbosus. Its relative scarcity in some of the shore beds is in part made up by its wider distribution in the deeper waters of the lake than the others reach, and on its presence on the isolated bars, where it was occasionally taken up by the dredge. On account of the great variability of Anodonta grandis and the difficulty in distinguishing the various forms, particular atten- tion was paid to this species as found in the lake, and the lake specimens were compared with numerous examples from the neigh- boring lakes and river. No Anodontas were found in the Tippe- canoe River near Lake Maxinkuckee Outlet, and we were therefore 56 Lake Maxinkuckee, Physical and Biological Survey unable to compare our lake specimens with the form that would be most interesting in this connection. The mussels of Tippecanoe Lake at the head of Tippecanoe River were examined in this connection. Blatchley (Indiana Geological Report for 1900, p. 190) has reported Anodonta grandis as common, and the subspecies footiana as frequent in Tippecanoe Lake. The Anodontas of that lake differ markedly both in the size and shape of the individuals from those of Lake Maxinkuckee. The difference in size can be easily explained by the more favorable conditions in Tippecanoe Lake. This body of water is more fluviatile than Lake Maxinkuckee, being directly con- nected with the Tippecanoe River, which is already a fairly large stream when it leaves the lake, and the mussel beds of the lake and river are continuous. The upper part of Tippecanoe Lake is exceptionally favorable for Anodontas ; the living mussels are large and abundant, and the dead shells almost pave the bottom near shore, several dead shells often being telescoped within each other. Some of the shells reached a size not often surpassed in the neighboring rivers, one example measuring 172.5 mm. long, 95 mm. high and 65 mm. in diameter. A few were thickened with a tendency to form half pearls, but most were thin. A number of the shells approached Anodonta corpulenta in general form, and one flattened, rounded shell resembled A. suborbiculata. The Anodontas from other lakes of the Tippecanoe River system, such as Center Lake and Eagle Lake near Warsaw, resembled those of Lake Maxinkuckee, but were generally smaller and shorter. The Anodontas of Lake Maxinkuckee were also compared with those of Yellow River a few miles to the north, and with the various lakes of the Kankakee system, including Upper Fish Lake, Lake of the Woods (Marshall Co) , Pretty Lake, Twin Lakes, Bass Lake and Cedar Lake. Some of the Yellow River Anodontas were nor- mal, oval shells such as are common in the rivers of northern In- diana; a few were exceptionally thin and exceedingly inflated, re- sembling A. corpulenta. Those of Upper Fish Lake — originally a fluviatile lake containing other fluviatile shells such as Q. undulata —were large shells like those of Tippecanoe Lake. The Anodontas of each of the other lakes differed more or less from those of the others, though all probably had a common origin. The only lake of this group, the Anodontas of which closely resembled those of Lake Maxinkuckee, is Bass Lake, and even here the shells were somewhat different, being smaller and with the epidermis more deeply stained. Even the Anodontas of Lost Lake differ slightly from those of Lake Maxinkuckee, being somewhat more inflated Lake Maxinkuckee, Physical and Biological Survey 57 and with the epidermis rather green than brown, and in having the shell usually somewhat thinner. Some of the shells near the outlet of Lost Lake are exceedingly thin, some of them so much so that ordinary print can easily be read through them; they are so fragile that it is almost impossible to keep them. Of the collection from Lake Maxinkuckee, mostly from Long Point, 26 examples were carefully compared. The smallest meas- ured 68 mm. long, 38 mm. high and 24.6 mm. in diameter, and the largest 93.5 mm. long, 50 mm. high and 37 mm. in diameter. Among variant forms was one female, gravid when collected, which was unusually elongate, its measurements being 86 mm. long, 43.5 mm. high and 32.5 mm. in diameter. In outline this shell closely resembled Anodontoides ferussacianus subcylin- draceus. Some of the larger specimens are rather humped and arcuate, the ventral margin of one being somewhat concave. This is a variation which is quite likely to occur in old shells of any species. Although gravid Anodontas were found rather frequently dur- ing the late autumn, no infected fishes were seen, and no young were found. The Anodontas of the lake are fairly free from parasites, a few Atax and Cotylaspis and occasionally a few distomids on the mantle next to the umbonal cavity being the only ones present in any numbers. In some of the other lakes the Anodontas were very badly infested; a colony found in one of the Twin Lakes being infested to a remarkable degree by a distomid which formed cysts in the margin of the mantle. Food and Parasites of various examples: — The following is the result of the examination of various examples of Anodontas from the lake. Sample 10. Vial containing intestinal contents of Anodonta grandis footiana, Lost Lake, Sept. 7, 1908. The vial contains a considerable amount of material (in formalin) which was sepa- rated into black fine mud below and fine flocculent light green above. Upper portion — Microcystis aeruginosa most common; Peridinium tabulatum some; Pediastrum boryanum; Melosira crenulata, a few filaments; Coelastrum microporum, Botryococcus braunii and Scenedesmus. Bottom layer — Lyngbya aestuarii, Microcystis aeruginosa very common; Peridinium tabulatum, Anuraea cochlearis, Cymbella cymbiformis and Navicula. Sample 11. Food of Anodonta grandis footiana, Lake Maxin- kuckee, near Norris Inlet, Aug. 20, 1908. A good mass of floc- culent fine green material; no mud. 58 Lake Maxinkuckee, Physical and Biological Survey Microcystis aeruginosa most common, Melosira filament, Oscil- latoria, short filament ; Anuraea cochlearis several ; Cymbella cymbiformis ; Gomphosphaeria aponina; Peridinium tabulatum; Coelosphaerium kuetzingianum, Lyngbya aestuarii, Epithemia argus, Chydorus, and what appears to be fragments of Ceratium hirundinella. Sample 12. Anodonta grandis footiana, near Norris Inlet, Lake Maxinkuckee, Aug. 20, 1908 ; a small mass of flocculent blue material. Microcystis aeruginosa most abundant; Lyngbya aestuarii, Melosira, Epithemia, Anuraea cochlearis, Pediastrum boryanum, Cosmarium intermedium and a few others, Staurastrum, Spirulina and Pediastrum duplex. Sample 13. Anodonta grandis footiana, 97 mm. long. Edge of Lake Maxinkuckee east of Norris Inlet, Aug. 29, 1908. Parasites, 9 Atax, free among gills. Mussels gravid, with ante- rior end of shell indented and with some brown spots on the nacre. Food mass fine golden brown, abundant in quantity, containing Anuraea cochlearis many; Microcystis aeruginosa most abundant element; Lyngbya aestuarii frequent; Scenedesnms, a few; Botry- ococcus braunii frequent, Cymbella cymbiformis; Staurastrum, Navicula; Fragilaria; Chydorus, a few; Coelosphaerium kuetz- ingianum; the diatoms are not abundant. Sample 14. Anodonta grandis footiana apparently old, 90 mm. long, near Norris Inlet, Lake Maxinkuckee, Ind., Aug. 29, 1908, the shell stained somewhat brown inside, with one steel-blue stain on the right valve anteriorly. Parasites ; Atax 7, large, full of eggs, one small, one very small, these all free among the gills; Cotylaspis insignis 1, in axil of gill. Food abundant; Microcystis aeruginosa abundant, Lyngbya aestuarii common, Pediastrum duplex, Botryococcus braunii, a few ; Cosmarium; Anuraea cochlearis several; Scenedesmus; Ankistro- desmus, and many diatoms, among which are Cocconeis pediculus, Melosira, Gomphonema, Navicula, Epithemia turgida, etc. Sample 15. Anodonta grandis footiana, 101 mm. long, Lake Maxinkuckee, near shore, by Norris Inlet, Aug. 29, 1908. Parasites, 5 Atax, free in gills, some full of eggs, 2 smaller in size, larval Atax (black) scattered in gills. Cotylaspis insignis 2, axil of inner gill. A large amount of food material in intestines, very fine, of a yellowish-brown color. Microcystis aeruginosa, Anuraea cochlearis, Lyngbya aestuarii, Botryococcus braunii, Coelosphaerium kuetzingianum, Cosmarium, Lake Maxinkuckee, Physical and Biological Survey 59 Navicula, an elongate form, Cymbella cymbiformis, Pediastrum duplex, P. boryanum; red cysts apparently of Peridinium. Sample 16. Anodonta grandis footiana, 90 mm. long, sandy bottom of Lake Maxinkuckee near Norris Inlet. Aug. 29, 1908. Mussel gravid. Parasites, A tax, 3, free among gills, Atax embryos scattered through gills. Food material scarce, fine golden brown in mass, consisting of Microcystis aeruginosa abundant; Coelosphaerium kuetzingianum abundant, Lyngbya aestuarii, a few filaments; Anuraea cochlearis and another rotifer ; Botryococcus braunii; Sorastrum, Coelastrum, Scenedesmus, Pediastrum duplex, Navicula several, Melosira tabu- lata, Synedra, Epithemia turgida, Cymbella cymbiformis; other small diatoms rather numerous; Cosmarium, a few. Sample 17. Anodonta grandis footiana, 93 mm. long. Sandy bottom of Lake Maxinkuckee near Norris Inlet, Aug. 28, 1908. Mussel gravid. Parasites, 1 Atax, free among gills. Intestines al- most empty. Microcystis aeruginosa one of most abundant ele- ments, Lyngbya aestuarii, Coelosphaerium kuetzingianum, Botry- ococcus braunii; Cosmarium, Pediastrum, Cocconeis pediculus, Epithemia turgida; Navicula, (1 actively moving) Gomphonema, Melosira tabulata, Anuraea cochlearis, Chydorus. Sample 18. Anodonta grandis footiana, 95 mm. long, Lake Maxinkuckee near Norris Inlet, Aug. 29, 1908. Mussel gravid. Parasites, 6 Atax free among gills, one a minute red species. Many young Atax embryos in inner side of mantle, not in gills. Food material golden brown with some green intermixed, very fine. Microcystis aeruginosa, common; Lyngbya aestuarii, a few filaments; Coelosphaerium kuetzingianum; Botryococcus braunii; Pediastrum duplex; Anuraea cochlearis a few ; Epithemia turgida,; Navicula, common ; Cymbella cymbiformis; Cocconeis pediculus, several; Cosmarium; Chydorus. Sample 19. Anodonta grandis footiana, Lake Maxinkuckee, near Winfield's. Mussel gravid. Parasites, young Atax in gills; distomids on mantle; (a slug pearl near hinge.) Food : Botryococcus braunii; Microcystis aeruginosa; Lyngbya aestuarii, Coelosphaerium kuetzingianum, Pediastrum duplex, Navicula, Cymbella cymbiformis. Sample 20. Anodonta grandis footiana, Lost Lake. Young transparent shell, gravid; length 77 mm., height 41 mm., diameter 30 mm. ; live weight 1 oz., shell ] oz. Parasites, several Cotylaspis insignis in axil of gills. Food chiefly Microcystis aeruginosa; con- siderable Botryococcus braunii. Sample 21. Anodonta grandis footiana, Lost Lake. Parasites, 60 Lake Maxinkuckee, Physical and Biological Survey 1 young Atax in gill; Cotylaspis insignis in axil of gill. Food chiefly Microcystis aeruginosa, a little Botryococcus braunii, Lyng- bya aestuarii and Pediastrum boryanum. 6. PAPER-SHELL ANODONTA IMBECILLIS Say A single specimen. 7. SQUAWFOOT Not very common in the lake. Occasional shells can be picked up along shore, especially between Long Point and Arlington, and along the north shore. Living examples were also taken in small numbers from the mussel bed at the mouth of Norris Inlet, and at Long Point. In a collection of about 300 living mussels collected at the latter place in the autumn of 1907, only 3 were of this species. As found in the various rivers of the country, this is one of the most variable of shells, and the exact limits of the species and its various forms are not yet well worked out. The lake examples, though differing considerably from those of the neighboring rivers and from river shells in general, do not exhibit a very large range of variation. They are all markedly dwarfed, the average length being about 2}- inches or 63.5 mm. long. All have a well-developed rounded posterior ridge. The epidermis is deeply stained, that of the exposed portion of the shell being a rich yellowish brown, while the anterior portion — in the living shell buried in the soil of the bottom — is a deep, shining, brown black. The anterior mar- gin is not nearly so heavy and produced as one frequently finds it in river examples. The beaks of the lake shells are not so angu- lar as they usually are in river shells, and the high wavy ridges are more numerous and pronounced. In the Maxinkuckee shells, also, a number of fine hair-like lines or ridges, much like growth lines, extend along the posterior border of the umbone, parallel with the posterior ridge of the earlier stages of the shell. The nacre of the lake shells is a rich rosy salmon. Unlike the salmon color of "Anodonta salmonia" this is a natural color, not due to diseased conditions; the nacre surface is very smooth and the color extends deeply into the shell. In some cases the inner nacreous surface appears to be a secondary thickening of the shell, laid on the older portions like an enamel. Below this extra nacreous deposit the growth lines are very distinct on the Lake Maxinkuckee, Physical and Biological Survey 61 inner surface of the shell. The rest periods are distinct black lines, often plainly visible through the translucent shell when held up to the light. Rays are always invisible by reflected light in the lake shells, but in some examples they were visible by trans- mitted light. The animal has orange-colored flesh. The few liv- ing examples examined indicate that parasites are common: one contained three old Atax ypsilophorus, and several young. One gravid example was found, October 17, 1907. The young- est example found was 42 mm. long and exhibited four rest periods. 8. LAMPSILIS GLANS (Lea) Fairly common in the main lake; dead shells are often found along shore, and occasionally the living mussels are to be seen in shallow water at the various mussel beds in the lake. It is quite abundant along the edges of the thoroughfare joining the lakes, and is common in Lost Lake. The examples found in the thorough- fare and Lost Lake were of unusually large size ; this is one of the few spscies of mussels which are as large or larger in the lake than in the neighboring rivers. L. glans appears to prefer shallow water along shore. A good number of shells recently cleaned out by muskrats was found near the water's edge at Long Point in the late autumn of 1913. In the Tippecanoe River at Belong this was a very abundant species in the greasy whitish blue clay along shore, and was here one of the favorite morsels of the muskrat. With the exception of Micromya fabalis this is the smallest species of mussel found in the lake. It can be easily recognized by its black epidermis, small size and purple nacre. 9. RAINBOW-SHELL LAMPSILIS IRIS (Lea) Rather common in the lake in shallow water near shore, found scattered among the other species in the various shell-beds. There is a good colony in the Lost Lake bed, and it is fairly abundant off the depot grounds, by Kruetzberger's pier, at Long Point, and at the bed near the mouth of Norris Inlet. The lake shells differ markedly from those of the neighboring rivers, so much so that it is easy to separate the lake and river shells at a glance. The lake shells are considerably more elongate, and the epidermis is stained a deep brown, mostly concealing the rays; when these are visible they are brownish rather than green, and the umbones are rather eroded. The shells, indeed, resemble 62 Lake Maxinkuckee, Physical and Biological Survey somewhat the males of L. subrostrata, with which they are asso- ciated. The lake shells exhibit a tendency to have their posterior margin somewhat broader than that of the river shells, and the shells are flatter at the posterior tip, becoming somewhat produced. The river shells are more solid and heavy. Lampsilis iris is one of the few species of mussels which does not show a marked decrease of size in the lake; indeed, some of the larger lake examples run actually larger than those from the neighboring rivers. Some of the largest lake shells examined have the following dimensions: No. Length mm. Alt. mm. Diam. mm. 1 69.6 37.3 21 2 65.9 34.9 21 3 68.0 34.6 22 4 64.9 35.8 22.7 5 67.0 36.8 20.9 6 67.7 33.8 21.5 No young shells were found, even the smallest appear rather old. The smallest three measure : Length mm. Alt. mm. Diam. mm. 41.4 21.2 12.5 38.9 21.5 12.5 37.0 20.0 12.3 For comparison with the lake shells, the dimensions are given of the largest two shells found in Yellow River : No. Length mm. Alt. mm. Diam. mm. 1 67.0 34.5 22.9 2 64.0 33.5 21.0 Only one gravid example was found ; this was obtained at Lost Lake bed Sept. 7, 1908. Of all the species of mussels in the lake, L. iris has the best connection, through scattered individuals along the Outlet, with the shells of the Tippecanoe River, a few shells having been found almost through the whole length of the Outlet. The outlet shells, like those of the rivers, are brightly rayed. The species is abund- ant in the Tippecanoe River at Belong. A number of examples were noted in spawning condition there in late August and early September in 1908. Observations in the Maumee River would in- dicate that these species, L. parva and L. midtiradiata, do not have exactly the same breeding season as many other species of Lamp- silis (luteola, recta, ligamentina, etc.) but are sometimes fertilized in July, spawning in August and September. Being small and Lake Maxinkuckee, Physical and Biological Survey 63 an early developing species, it is probable that they have somewhat different habits: indeed it is possible that they have more breed- ing seasons per year than the other species. The Tippecanoe mussels of this species were a favorite food of the muskrat, and were killed in great numbers every autumn, the dead shells being thickly strewn along the bank, or piled in heaps at the bases of rocks which the rodent had used as a feeding place. Lampsilis iris has a well marked tendency in the lakes and Outlet to produce pearls and baroques, but these are too small to be of any value. 10. LAMPSILIS SUBROSTRATA (Say) Lampsilis subrostrata reaches its best development along the muddy shores of lagoons, not being perfectly at home either in swiftly flowing streams or in perfectly quiet lakes, although occa- sional examples may be found in either. It is considerably more abundant in Lake Tippecanoe and Upper Fish Lake than in any other Indiana lakes examined. Along the edges of the Mississippi sloughs it is fairly common and reaches a large size, often distin- guished with difficulty from Lampsilis fallaciosa except for the thinness of the shell and the black epidermis. It is rare in Lake Maxinkuckee, only a few examples having been obtained from the mussel bed near Norris Inlet. It is much more common in Lost Lake in the large bed along shore south of the Bardsley cottage. Mr. Blatchley, in a short report on the mollusks of the lake, (25th annual report, Department of Geol-ogy and Natural Resources of Indiana, 1900, p. 250), says of this species: "Not common in the main lake ; more so in the muck and mud along the margins of Lost Lake, where a well-marked variety, with a larger and broader beak, was taken. A specimen of this was sent, among others, to Mr. Chas. T. Simpson, of the Smithsonian Institution, for verification. In his reply he says : The variety of subrostratus which you send is, so, far as I know, confined to northern Indiana. It is quite re- markable, and would seem to be almost a distinct species. I have seen quite a number of specimens of it, and at first thought it a variety of U. nasutus, but there seem to be intermediate forms con- necting it with U. subrostratus.' " With the exception of the differences due to sex, all the Maxin- kuckee and Lost Lake shells are very uniform in appearance, much more so than L. luteola, and are hardly distinguishable from ex- amples from Lake Tippecanoe, Upper Fish Lake, or a specimen col- lected in the Wabash River at Terre Haute by Dr. J. T. Scovell. 64 Lake Maxinkuckee, Physical and Biological Survey They are dark brown in color with very faint rays. The species appears to be rare in the Tippecanoe River at Belong. One ex- ample was obtained there, which is somewhat shorter and stouter than those of the lake, and not so badly stained; it shows faint rays posteriorly. The Lost Lake shells are somewhat larger than those found at the other lakes. No young were found, the smallest shell obtained being a half-grown example. One gravid specimen was found at Lost Lake Sept. 7, 1908. The marsupium closely resembles that of L. iris, being a kidney-shaped mass filling the hinder portion of the outer gill, this mass being marked into seg- ments by rather deep radiating furrows. The very edge of the mar- supium is white beyond the dusky submarginal area, the white making a chain-like area at the edge of the gill. Like L. iris, this species has a tendency to form pearls, but they are too small to be of any value. Food of individuals: — The following is the result of the exam- ination of the contents of the intestines of L. subrostrata from Lost Lake at various dates. Sample 22, August 20, 1908. A small amount of flocculent bluish-gray material. Peridinium tabulatum abundant ; Microcystis aeruginosa abund- ant; Anuraea cochlearis; Pediastrum boryanum; Diatoms — Sy- nedra, Cymbella cymbiformis. Sample 23, August 20, 1908. A very small amount of floccu- lent grayish material. Peridinium tabulatum a few; Microcystis aeruginosa a little; Pediastrum boryanum; Cosmarium, Tetraedron minimum, Scene- desmus, Euglyphia alveolata; Peridinium, a small, sharp-spined form. Diatoms make up the greater part, including Cymbella cymbiformis, Navicula, Fragilaria, Coscinodiscus, and Epithemia. Sample 24, September 7. A large amount of material, black mud below, greenish flocculent material above. The upper por- tion contains chiefly Botryococcus braunii and Microcystis aerug- inosa. Bottom portion — Microcystis aeruginosa common; Botry- ococcus braunii; Peridinium tabulatum, Peridinium, a small spined species; Scenedesmus, frequent. Staurastrum, Pediastrum duplex; Coelastrum a few; Anuraea cochlearis, Tetraedron, Docidium, Coelosphaerium kuetzingianum, sponge spicule, Lyngbya aestuarii. Diatoms, — Synedra, Navicula, Gomphonema, etc. Lake Maxinkuckee, Physical and Biological Survey 65 11. FAT MUCKET LAMPSILIS LUTEOLA (Lamarck) Lampsilis luteola is the most widely distributed of the Amer- ican Unionidse, its range extending over nearly all of North Amer- ica east of the Rocky Mountains. It lives and thrives under a great variety of conditions, being frequent in both lakes and rivers. In Lake Maxinkuckee this is the most common mussel, being found almost everywhere in water from 2 to 5 or 6 feet deep where the bottom is suitable. It prefers a rather solid bottom with some admixture of sand or gravel, but occurs also even where the bot- tom is of a rather firm peaty nature as in some places in Outlet Bay. It is, however, rather scarce and widely scattered in such localities. The best beds are found at Long Point, at Farrar's, in front of McDonald's, by the old Kruetzberger pier, and in Aubeenaubee Bay off from the Military Academy. In Lost Lake it was abundant in the large mussel bed below the Bardsley cot- tage, and a few shells were found in the north end of the lake. The Lake Maxinkuckee shells are smaller and thinner than those of the rivers; they closely resemble those of most of the neighboring lakes with which they were compared, such as Twin Lakes, Pretty Lake, Bass Lake, etc. The L. luteola of Upper Fish Lake are much larger and more like river shells. Compared with specimens of more remote lakes, those of Lake Erie are much smaller, more solid and not stained, the rays being quite distinct. The L. luteola of Lake Pokegama, Minn., are unlike any of those above cited, being large, thick and heavy, furnishing excellent but- ton material. Lampsilis luteola is represented in Lake Maxinkuckee and Lost Lake by 2 forms; although these forms are well connected by intergrades the extremes are pretty markedly distinct. The colony in Lost Lake is composed of compressed, elongate shells, almost as large as those found in rivers, but considerably thinner. It is in the females of this group, and only in part of them, that the greatest variation occurs. The males are not much unlike the ordinary well-known form of the neighboring rivers. The most strongly aberrant females are markedly compressed, and flare out broadly in the post-basal region. The umbones are far forward and they remind one somewhat in contour of the marine species, Modioki plicatula. Some of them closely resemble Lamp- silis radiata of the Atlantic drainage. The Lost Lake mussels of this species are stained a peculiar attractive ash-gray which does not greatly obscure the rays. They are not so heavily encrusted 5—17618- -Vol. 2 66 Lake Maxinkuckee, Physical and Biological Survey with marl as are those in the Lake Maxinkuckee beds. Typical Lake Maxinkuckee specimens are dwarfed and stained a deep brown, which obscures the rays. Most of them are thickly coated posteriorly with incrustations of marl. It is principally this spe- cies which has associated with it the little water-beetle, Stenelmis undulatus Blatchley. At Long Point, where L. luteola is the most common mussel, examples of the peculiar Lost Lake form are rather frequent. In comparing sets of shells from the various mussel beds of the lake — Long Point, Farrar's and the Norris Inlet beds — it was noted that the mussels of each bed, as one approached the upper portions of the lake, averaged somewhat smaller. As regards food, movements, reproduction, etc., L. luteola does not differ greatly from the other mussels of the lake with the ex- ception that it appears to be considerably the most active species in the lake. A few were observed moving about during the winter of 1900-1901. The deep water individuals rarely move about at all. In the autumn of 1913 the migration of those near shore into deep water was strikingly shown by a series of numer- ous furrows, with a mussel at the deep water end and extending from shore outward near Long Point. As with the other mussels of the lake, reproduction is a rather inconspicuous phenomenon, not attended with the marked display common in the larger river examples. Of 252 examples collected at Long Point Oct. 17, 1907, 25 contained glochidia in the gills, some being very full and much distended. One was found gravid May 24, 1901, and on August 22, 1906, some in Lost Lake appeared to be about ready to spawn. The young of this species were found rather frequently in the lake, much more frequently, indeed, than any other kind. The smallest examples were obtained while sieving sand for Sphaeriums at Long Point. These young mussels live buried in the fine sand near shore. Specimens up to about a half inch long are very crinkly, being covered with narrow elevated parallel ridges, gen- erally 5 in number, each consisting of 2 open loops placed end to end, the sides of the loops being roughly parallel with the ventral margin of the shell; the ends where they join form a sharp curve upward toward the umbone. These double loops are followed by a number of broken irregular ridges. The markings just described persist on the umbones of the older shells until eroded away. The half grown shells are beautifully rayed with green on a whitish background. As the shells grow older they become gradually stained a deep uniform brown, obscuring the rays. Lake Maxinkuckee, Physical and Biological Survey 67 Most of the mussels of the lake are slightly parasitized, none abundantly; they contain a few examples of a small reddish Atax, and a few Cotylaspis insignis. A small round-worm, somewhat like a vinegar eel, was found very active in the intestine of one specimen; it was probably parasitic. Small irregular pearls or slugs are produced but they are of no value. In some rivers this species produces an abundance of small round pearls. Some of the pearl-bearing river specimens were planted in the lake in 1912 to see if they would infect the lake shells. The Lampsilis luteola of the rivers is a fair button shell, but the Lake Maxinkuckee shells are too small and thin to have much value. It is a remarkable fact that in Lake Pokegama, Minn., L. luteola grows abundantly in shallow bottom among the weeds, and there produces a handsome thick heavy shell, one indeed concerning which the pearl button manufacturers are very enthusi- astic, so much so that the shells at that distant point from the market brought $22.00 per ton; in the summer of 1912, two car- loads of these shells were shipped to Europe. Just why the Lake Maxinkuckee shells are not like the excel- lent ones of Lake Pokegama remains as yet unanswered, but seems to be largely a question of breed. It would certainly be worth while to introduce the Lake Pokegama breed into Lake Maxin- kuckee. Following is the result of the examination of various indi- viduals of the Maxinkuckee and Lost Lake shells: Sample 25. L. luteola. Lost Lake, Sept. 7, 1908. Mussel gravid. Length 100 mm., altitude 62 mm. ; diameter 33 mm. Live weight 3^ oz. ; shell If oz. Parasites — 7 free Atax among gills, young Atax in gills and numerous Atax eggs on interior surface of mantle. Food chiefly Microcystis aeruginosa, Botryococcus braunii, Lyngbya aestuarii, Melosira, Navicula. Sample 26. L. luteola, Lost Lake, Sept. 7, 1908 ; mussel gravid ; length 95 mm., alt., 60 mm., diam., 38 mm. ; live weight 3f oz. ; shell If oz. Parasites, 7 free Atax in gills, and Atax eggs in the mantle. Food — chiefly Microcystis aeruginosa, also Botryococcus braunii, Navicula, Lyngbya aestuarii and Anuraea cochlearis. Sample 27. L. luteola, Lost Lake by Bardsley's, Sept. 7, 1908 ; live weight 3] oz. ; shell 1-i oz. ; length 97 mm., alt. 54 mm., diam. 33 mm. Parasites — 7 free Atax among gills; many small red eggs of A tax on inner surface of mantle. Food chiefly Microcystis aeruginosa, Botryococcus braunii and Navicula. Sample 28. Lampsilis luteola, Lost Lake, Sept. 7, 1908. Live 68 Lake Maxinkuckee, Physical and Biological Survey weight 3$ oz. ; length 104 mm., alt. 54 mm., diameter 33 mm. Parasites, Atax 6, free among gills, eggs of Atax on inner side of mantle, young in pits on side of foot. Food, Microcystis aerug- inosa most common. Lyngbya aestuarii, Navicula, Melosira, Anuraea and Cymbella. Intestinal contents of two examples of L. luteola obtained in Lake Maxinkuckee Aug. 27, 1908, near the shore just north of the ice-office gave the following results : Sample 29. Microcystis aeruginosa, main mass ; Anuraea coch- learis a few; Botryococcus braunii rather common; Cymbella cymbiformis, one; Lyngbya aesturaii, 1 filament; Navicula, 2 ex- amples ; Synedra, a few. Sample 30. Microcystis aeruginosa main mass; Botryococcus braunii, very common ; Lyngbya aesturarii, several filaments ; Anuraea cochlearis a few; Synedra some; Navicula one example, very lively; Cosmarium one round worm like vinegar eel, very lively. Sample 31. Lost Lake, 1908. A good mass of material, black- ish below, flocculent greenish above. Lyngbya aesturarii, a few filaments ; Microcystis aeruginosa, quite abundant; Anuraea cochlearis; sponge spicule, Pediastrum duplex, Staurastrum, Botryococcus braunii, Peridinium tabulatum, a few; Peridinium, a small spiny species 1 ; Pediastrum boryanum; several diatoms — Navicula, Coscinodiscus, Melosira, Cymbella cymbiformis; Microcystis is the most abundant element, Peridinium is rather scarce. Sample 32. Lake Maxinkuckee, Aug. 27, 1908. A small amount of brownish green flocculent material. Anuraea cochlearis, quite frequent; Lyngbya aestuarii, short filament; Peridinium tabulatum, a few; Coelastrum microporum; Coelosphaerium kuetzingianum ; Pediastrum boryanum; Scenedes- mus, very few ; Chydorus fragment. Diatoms, — Epithemia turgida, Navicula, Cymbella cymbiformis, Gomphonema, Coscinodiscus. Sample 33. Lake Maxinkuckee, Aug. 27, 1908. A fair amount of brownish green material, muddy below, flocculent green above. The green top material consisting chiefly of Microcystis aerug- inosa; with some Anuraea cochlearis; Lyngbya aestuarii; Micro- cystis aeruginosa; Bulbochaete bristle; Coelastrum microporum; Merismopedia glauca; Pediastrum boryanum; diatoms — Navicula, Coscinodiscus, etc. Measurements: — The following is a series of measurements of Lost Lake examples: Lake Maxinkuckee, Physical and Biological Survey G9 MEASUREMENTS IN MM Vr\ T5 1 Length Alt. Diam. 1189 August 20 85 54 32 Fanshaped female. 1260 September 7 97.4 55 31 Fanshaped female, gravid. 1215 August 20 87 46 35.6 Fanshaped female. 1224 August 20 98 56 26 Fanshaped female. 1245 August 20 90 51 32.8 Fanshaped female. 1235 August 20 98 48.9 36.3 Male. 1188 August 20 102 53 36 Male. 1221 August 20 100 51 37 Male. 1223 August 20 96 51.4 34.8 Male. 1228 August 20 102.3 53.7 33 Male. Most of these shells blistered posteriorly. The males are fairly like those of river; the females are more fanshaped. Weight of the 10 shells, 15 oz.: only a few are rayed. 12. POCKETBOOK LAMPSILIS VENTRICOSA (Barnes) Rather common at the Long Point mussel bed ; a few found in the bed by Farrar's and a few in Lost Lake. The species as found in the lake is markedly dwarfed and quite different in ap- pearance from the usual river form. There are two types in the Long Point bed. One consisting of females, having the post basal inflation of the shell characteristic of that sex, not exactly as in the river form, however, but somewhat more restricted ; this feature, along with a peculiar stain of the epidermis which con- ceals the normal coloring of' the shell, causes them to very closely resemble a short female L. luteola. The other type, an oval shell without the post-basal inflation, was at first taken to represent the males, but some of them were found to contain glochidia. These, too, bear a marked resemblance to L. luteola, and the only way to distinguish the two species, as they occur in the lake, is by an examination of the umbonal sculpture. This in ventricosa con- sists of a few coarse parallel ridges; in luteola the sculpture is of numerous fine wavy lines. The lake L. ventricosa was so markedly different from the species as usually known that it was compared with a large series of both lake and river forms. Of river shells only a few from the central part of the Maumee, where for some reason the shells are markedly dwarfed, bore any close resemblance to it. None was found in any of the neighboring lakes with which to compare them. In some of the small lakes of Michigan where Dr. Robert E. Coker collected, he experienced a similar difficulty in dis- tinguishing L. ventricosa and L. luteola. He sent sets of criti- 70 Lake Maxinkuckee, Physical and Biological Survey cal specimens to Mr. Bryant Walker of Detroit, Mich., who identi- fied the shells with a few coarse straight undulations on the beaks as Lampsilis ventricosa canadensis and the others as L. luteola. The Maxinkuckee specimens were also compared with L. ventri- cosa from Lake Champlain, and were found to be much like them. The Champlain examples which were free from staining of the epidermis more closely resembled in color the ventricosa of the rivers. The specimens of L. ventricosa differed considerably in the dif- ferent beds. Lost Lake examples. are usually rather small, and are stained a peculiar ashy-gray. Those from the near Farrar's are mostly small and apparently young and are rather well rayed; they resemble river forms more closely than any others in the lake. The large oval L. ventricosa of Long Point are the heaviest shells of the lake. A peculiarity of several of these shells is a conspicuous rib-like thickening on the inside, extending from near the umbonal cavity postero-ventrally. The nacre is soft satiny in luster, and not very iridescent. This oval form of ventricosa found at Long Point furnishes the only shell in the lake that could be used to any advantage in the manufacture of buttons, and even it produces rather inferior material. Some of these shells were sent to a button factory at Davenport and buttons were made of them. The following is a set of measurements of these large shells : No- Date, 1907 Length mm. Alt. mm. Diam. mm. Remarks 1 September 24 114 74.8 53 Female gravid. 2 October 30 107.6 65.5 54.8 3 October 2 105.2 63.7 52.5 4 October 30 92.5 60.4 53.7 Female gravid. 5 October 30 103.7 67.3 49.3 Dorsal baroques. 6 October 1 7 98.6 60.2 55.5 Arcuate; baroque found. 7 October 20 101.7 63.6 52.2 8 October 30 94.6 58. 4 53.2 Nacre diseased and blistered. 9 October 17 95 .6 55.7 49 10 October 17 91.5 60.4 49.5 Although the reproductive phase of L. ventricosa of the lake is much less conspicuous than in the river mussels, most of them apparently succeed in reproducing themselves. Most of the fe- males found later in autumn have more or less numerous glochidia in the gills. No infected fishes or very young mussels of this spe- cies were seen. The most common parasite is Atax, and it is not particularly abundant. Of six examples collected near Farrar's July 24, 1909, Lake Maxinkuckee, Physical and Biological Survey 71 the first contained 9 of the mites, the second 4, the third 15, with Atax eggs in the mantle and body, the fourth 12 Atax and nu- merous eggs of the mite on the inner surface of the mantle, the fifth 3 Atax with eggs and the sixth 7 A tax with eggs and egg scars. No other parasites were noted. No pearls were found, only a few irregular slugs. In 1906 some of the immense L. ventricosa of Yellow River were planted in the lake near shore not far from the old ice office. A few died shortly after planting but near the same place 2 years later some of the mussels were found alive and apparently thriv- ing. Two of the large females were killed and examined. Altho this was at a time when this species is usually gravid, one of these individuals was sterile, apparently having failed to become impreg- nated. The influence of its residence in the lake was marked by a dark stain which covered the exposed portion of the shell. The other had a few eggs in. the gills, and numerous marginal cysts in the mantle. About 10 Atax among the gills, and numerous dis- tomids on the outside surface of the mantle in the umbonal cavity. 13. LAMPSILIS MULTIRADIATA (Lea) Not abundant in the lake; occasional shells are found along shore, and now and then they are encountered in the piles of shells where muskrats have been feeding. A few living examples were found in the mussel bed near the mouth of Norris Inlet and a few at Long Point bed. In all hardly a dozen living examples were secured ; of 563 shells taken from a pile left by a muskrat at Long Point in 1907, only 1 was of this species. This mussel, as it occurs in the lake, is not nearly so attractive as river specimens, being dwarfed and so deeply stained that the rays are inconspicuous, being usually black or dull brown instead of green. This species was found in unusual abundance in the Tippecanoe River at Belong, and a considerable number was observed spawn- ing during the autumn of 1908. While spawning, this mussel is a very conspicuous spectacle. It lies either on its back, or more usually with the posterior end directly upward, and the showy edges of the mantle, which are of a yellowish brown color, and cross-barred with narrow lines which are continuous with the fine rays of the epidermis, look a good deal like a small darter lying on the bottom. Long waving pennant-like flaps, with a showy black spot at the base of each are developed, and this portion of the mussel is made still more conspicuous by reason of periodic violent spasmodic contractions. 72 Lake Maxinkuckee, Physical and Biological Survey At the Tippecanoe River this is one of the favorite foods of the muskrat, and it must be difficult for them to hold their own against that rodent. 14. MICROMYA FABALIS (Lea) Rare; previous to 1913 only one shell had been found; this was picked up on the north shore of the lake in 1907. In 1913 several shells, recently cleaned out by some animal, probably a muskrat, were found at the wagon bridge. This species is fairly common in Tippecanoe Lake and frequent in the Tippecanoe River at Belong where it was collected in shallow water near shore in rather stiff blue clay. It is the smallest of our Unionidse. The white or bluish white nacre has an exceedingly brilliant luster. Several other species of mussels have been recorded for the lake, among them Quadrula lachrymosa (Lea) , Alasmodonta mar- ginata Say, Symphynota compressa Lea, Anodontoides ferussaci- anus (Lea), Ptychobranchus phaseolus (Hildreth), Obovaria circu- lus Lea, Lampsilis parva (Barnes) , and Lampsilis gracilis (Barnes) . We have seen representatives of none of these species from the lake, and while some, such as A. ferussacianus, are very probably pres- ent, others are very improbable. MOLLUSKS OTHER THAN UNIONID^ About 116 species of mollusks in addition to the Unionida? are known to occur in Lake Maxinkuckee or its immediate vicinity. Specimens of nearly all of these species were collected during our investigations; others were collected by the late L. E. Daniels. These collections were referred to Dr. Paul Bartsch of the United States National Museum for study and report. Other duties have prevented Dr. Bartsch from completing his full report on these mollusks. He has, however, supplied the following list of his identifications. This shows that the Lake Maxinkuckee molluscous fauna is a remarkably rich one, the total number of species, in- cluding the Unionidse, being not fewer than 130. FRESHWATER MOLLUSKS 1. Lymntea palustris (Miiller) 2. Lymnsca obrussa exigua (Lea) 3. LymnsKd danielsi Baker 4. Lymnsea dalli Baker 5. Lymntea humilis (Say) 6. Lymnsea desidiosa (Say) 7. Planorbis bicarinatus Say Lake Maxinkuckee, Physical and Biological Survey 73 8. Planorbis trivolvis Say 9. Planorbis campanulatus Say 10. Planorbis parvus Say 11. Planorbis exacutus Say 12. Planorbis albus Miiller 13. Segmentina armigera (Say) 14. Physa integra Haldeman 15. Physa heterostropha Say 16. Ancylus tardus Say 17. Ancylus shimekii Pilsbry 18. Ancylus rivularis Say 19. Ancylus kirklandi Walker 20. Viviparus contectoides W. G. Binney 21. Viviparus intertextus (Say) 22. Campeloma decisa (Say) 23. Valvata tricarinata (Say) 24. Valvata sincem simplex Gould 25. Amnicola limosa (Say) 26. Amnicola limosa porata (Say) 27. Amnicola lustrica Pilsbry 28. Amnicola walkeri Pilsbry 29. Angitrema armigera (Say) 30. Pleurocera subulare (Lea) 31. Pleurocera subulare intensum (Reeve) 32. Pleurocera canaliculatum (Say) 33. Pleurocera undulatum (Say) 34. Pleurocera moniliferum (Lea) 35. Goniobasis louisvillensis Lea 36. Goniobasis depygis (Say) 37. Goniobasis livescens (Menke) 38. Goniobasis pulchella (Anthony) 39. Sphserium flavum (Prime) 40. Sphserium occidentals Prime 41. Sphserium rhomboideum (Say) 42. Sphserium simile (Say) 43. Sphserium solidum (Prime) 44. Sphserium stamineum (Conrad) 45. Sphserium striatinum (Lamarck) 46. Sphserium sulcatum (Lamarck) 47. Sphserium tennis Sterki 48. Sphserium tumidulum Sterki 49. Sphserium walkeri Sterki 50. Musculium rosaceum (Prime) 74 Lake Maxinkuckee, Physical and Biological Survey 51. Musculium ryckholti (Sterki) 52. Musculium securis (Prime) 53. Musculium transversum (Say) 54. Musculium truncatum (Linsley) 55. Pisidium mainense Sterki 56. Pisidium medianum Sterki 57. Pisidium milium Haldeman 58. Pisidium nove-boracense Prime 59. Pisidium pauperculum Sterki 60. Pisidium pauperculum crystalen.se Sterki 61. Pisidium sargenti Sterki 62. Pisidium scutellatum Sterki 63. Pisidium splendidulum Sterki 64. Pisidium strengii Sterki 65. Pisidium tenuissimum Sterki 66. Pisidium ivalkeri Sterki 67. Pisidium abditum Haldeman 68. Pisidium affine Sterki 69. Pisidium compressum Prime 70. Pisidium compressum Issvigatus Sterki 71. Pisidium idahoense Sterki 72. Pisidium, indianense Sterki 73. Pisidium lacustrinum Sterki 74. Pisidium virginicum Bourginat 75. Pisidium rotundatum Prime 76. Pisidium variabile Prime 77. Pisidium politum Sterki 78. Pisidium vesiculare Sterki 79. Pisidium subrotundatutn Sterki LAND MOLLUSKS 80. Polygyra hirsuta (Say) 81. Polygyra fraterna (Say) 82. Polygyra monodon (Rackett) 83. Polygyra thyroides (Say) 84. Polygyra thyroides bucculenta (Gould) 85. Polygyra elevata (Say) 86. Polygyra zaleta (Binney) 87. Polygyra profunda (Say) 88. Polygyra multilineata (Say) 89. Polygyra multilineata algonquinensis Nason 90. Pyramidula alternata (Say) 91. Pyramidula cronkhitei anthonyi Pilsbry & Ferriss Lake Maxinkuckee, Physical and Biological Survey 75 92. Pyramidula perspective (Say) 93. Helicodiscus parallelus (Say) 94. Zonitoides arboreus (Say) 95. Zonitoides nitidus (Miiller) 96. Zonitoides minusculus (Binney) 97. Euconulus fulvus (Miiller) 98. Polita hammonis (Strom) 99. Polita indentata (Say) 100. Vallonia pulchella (Miiller) 101. Vallonia costata (Miiller) 102. Cochlicopa lubrica (Miiller) 103. Strobilops labyrinthica (Say) 104. Strobilops virgo Pilsbry 105. Strobilops affinis Pilsbry 106. Pupoides marginatus (Say) 107. Pupilla muscorum (Linnaeus) 108. Gastrocopta armifera (Say) 109. Gastrocopta contracta (Say) 110. Gastrocopta tappaniana (Adams) 111. Vertigo rnorsei Sterki 112. Carychium exile H. C. Lea 113. Carychium exiguum (Say) 114. Succinea retusa Lea 115. Succinea obliqua Say 116. Succinea avara Say THE CRUSTACEANS A comprehensive study of the Plankton was made by Professor Chancey Juday now of the University of Wisconsin. A similar thorough study of the Parasitic Copepods was made by Dr. Charles B. Wilson whose report is made part of this paper. Except during the summer of 1899 and 1900 the field work on Lake Maxinkuckee was nearly all done by one or two investigators only. This made it impossible to pay equal attention to all the groups of animals and plants; indeed, many groups could receive scarcely more than passing notice, while others had to be wholly neglected. Among those which received but slight attention are the worms, polyzoans, protozoans, smaller crustaceans, insects, and the like. Although considerable collections were made in some of these groups, insurmountable difficulty was experienced in finding specialists to work them up. Our reports on several of those groups are therefore necessarily brief and general in character. 76 Lake Maxinkuckee, Physical and Biological Survey Occasional notes and memoranda were made regarding various species which we did not have opportunity to observe regularly or methodically. Such of these as seem to possess some value or in- terest are given in the following pages. The list of species contained in the Plankton collections of 1899 and 1900 and a discussion of their abundance, distribution and habits will be found in Professor Juday's report. A few addi- tional species were later obtained in the small ponds about the lake. Of the individual species not much can be said ; our studies were too general for that purpose. It may be stated, however, that plankton species of crustaceans constitute a large part, probably nearly all, of the first food of young fishes, and much of the food of some species of fishes throughout their entire lives. The little Stickleback (Eucalia in- constans) , for example, may be mentioned as one of such species. Examples of this species kept in an aquarium fed eagerly on any and all plankton crustaceans which we placed in the aquarium with them. We observed also that these small crustaceans are captured and eaten freely by those curious carnivorous plants, the bladder- worts. Of the whole group, it can be said that they are present through- out the year in greater or less abundance. The abundance varies greatly, however, from time to time, as shown by Juday. On Sep- tember 6 (1906), peculiar ripples were observed on the surface of the otherwise smooth lake. Upon cautiously approaching the spot it was found that the disturbance was caused by large schools of very young black bass, circling about and feeding voraciously. Upon drawing a towing-net through the place great quantities of several species of plankton crustaceans were obtained. On many occasions the lake surface in large areas was seen to be covered with a thin scum which, on examination, was found to consist chiefly of the cast-off skins of minute crustaceans. On November 5 (1906), Entomostraca were present in such re- markable abundance at and near the surface of the lake that the water had the appearance and consistency of thick soup, the little animals actually crowding each other in the water. The next day great windrows of these crustaceans were found washed up on the shore at Long Point, Two days later they were again observed forming dense clouds at and near the surface of the lake off the Morris boathouse. A 4-drachm vial was simply dipped into the water and about 100 of the creatures were secured. A quantity of plankton collected July 7 (1909), and examined qualitatively by Professor A. A. Doolittle of the department of Lake Maxinkuckee, Physical and Biological Survey 77 biology, Washington, D. C., high schools, gave the following results : Species. Per cent. Diaptomus oregonensis Lilljeborg1 0.38 Cyclops leuckarti Glaus; (edax Forbes) 4.11 Diaphanosoma leuchtenbergianum Fischer 0.40 Daphnia retrocurva Forbes, var 1.06 Daphnia hyalina Leydig 84 . 02 99.97 The Copepods (free-swimming species) frequently bear at- tached Protozoa, sometimes in such numbers as to make them ap- pear bristly. They seem to be more abundant in winter when the lake is covered with ice. Whenever holes are cut through the ice these crustaceans often come crowding to the light and air. The Cladocera are, generally speaking, the larger and more showy element of the crustacean plankton. Their stomach con- tents, which at times forms conspicuous masses, was found to be composed largely of phyto-plankton elements, especially Botryo- coccus braunii which, because of its color, was easily recognizable. One of the smaller Cladocera, Chydorus, was found to constitute an important part of the food of the Unionidas or mussels of the lake, as it also does of the small fishes. One of the most notable species of the Zoo-plankton was Lepto- dora hyalina. This is usually a deep-water species, but on Sep- tember 2 (1906), it was taken in quantities in a surface tow-net in Outlet Bay. Though one of the largest of the plankton crusta- ceans, this species is so transparent as to be quite invisible except by its movements among the associated individuals of Lyngbya. Two other species of Entotomostraca not usually classed as plankton, were noted, namely, the fairy shrimps. One, Branchip- us serratus, was found dead in large numbers floating on the sur- face in deep water July 11 (1899). Later in the same day, consid- erable numbers were seined in shallow water off Norris Inlet. Again on August 21 and 31, a few were seen floating. Another species, Branchipus vernalis, was found abundantly in small temporary ponds west and south of the lake in the spring of 1901. A school of these curious crustaceans of delicate structure and pearly appearance, apparently usually swimming on their backs, their numerous gill-feet moving rapidly in the water, makes a very pretty sight. The Parasitic Copepods are reported on by Dr. Wilson (pp. 79- 82) . It may be here remarked that, as compared with other bodies 78 Lake Maxinkuckee, Physical and Biological Survey of water, these forms are comparatively rare in Lake Maxinkuckee. In certain rivers which we have examined, particularly the Kanka- kee, Maumee, and the sloughs along the Mississippi, certain large species of Lernsea are so abundant during the summer and fall that they infest most of the rock bass, crappies, and bluegills. They seemed to be worst on the rock bass, nearly every one of which was bleeding in one or more places where these parasites had fastened in their skin. At this season these fishes are said to be "wormy" and are rejected by anglers and others who chance to catch them. The Isopods or Sowbugs are represented at the lake by two aquatic species, one in the lake proper, the other (Porcellio scaber) , in the woodland ponds and in damp places. The lake species is abundant all the year round among the Chara, especially in Outlet Bay. It is one of the most important foods, particularly of rock bass and bluegills. It sometimes forms the greater part of the food of those species. Little or nothing was learned of the habits of the pond species. There are, of course, several land species of these curious crustaceans. The Amphipods are represented by several species in the lake and the neighboring ponds. A large species was found near shore, and smaller forms farther out in the lake among the aquatic plants. The Hornwort (Ceratophyllum demersum) was one of their favor- ite haunts. Some of our herbarium specimens of this plant were found full of these beach fleas. Many specimens were obtained from the plants raked up from various depths. The Amphipods could be obtained by washing the plants in a tub or bucket of water. A few were taken at night in the towing-net. Some were found in stomachs of fishes seined August 3 (1906), south of Arling- ton station. The freshwater shrimp (Palaemonetcs exilipes) was not com- mon in or about the lake. Only a few were obtained, one on Au- gust 2 (1899), one on September 6 (1899), and one on October 23 (1900), all in the Outlet. Two were secured in Lost Lake, one on August 1, the other September 1 (1900). Another was taken November 27 (1900), upon a mass of aquatic plants dredged some distance from shore in the lake. This species therefore ap- pears to be rather rare at this lake. In Little River near Aboite, Allen Co., Indiana, immense numbers of this shrimp were found in masses of Ceratophyllum from which the transparent creatures jumped with great alacrity when hauled up out of the water. They were found in great abundance also in Chester River, near Chester, Md. Lake Maxinkuckee, Physical and Biological Survey 79 THE COPEPOD PARASITES BY CHARLES B. WILSON, Professor of Biology, State Normal School, Westfield, Mass. Three species of Argulus, two of Ergasilus, and one of Ach- theres were found upon the fish of the lake. The species of Argu- lus have all been described elsewhere (Proc. U. S. Nat. Mus., XXV, pp. 709, 715, 718). The life history of one species, A. maculosus, was obtained in full, and a brief account was published in 1907 (Proc. U. S. Nat. Mus., XXXII, p. 416). Of the two species of Ergasilus, one (E. centrarchidarum) has been described by Wright*. This species is common everywhere on all fishes of the perch family. The other species was new to science ; it was named E. versicolor, and a full description with figures was published in 1911 (Proc. U. S. Nat. Mus., XXXIX, p. 341: pi. 45). The single species of Achtheres, A. ambloplitis, has also been described by Wright, Kellicott, and others, but several details were here supplied that had hitherto been lacking. The complete life-history was also worked out for both genera ; that of Achtheres had been partially described before by Claus and Kellicott, while not a single detail had ever been published for Ergasilus. I. ARGULUS CATOSTOMI Dana & Herrick Found in the gill-cavity of the white sucker, Catostomus com- mersonii. The discovery of this species in Indiana, together with those recorded from Lake Champlain and the rivers of Mas'sa- chusetts, Connecticut, and New York, shows the distribution of this parasite to be identical with that of the host it infests. The specimens here obtained and those from Lake Champlain include males, the first of that sex to be recorded for this species. 2. ARGULUS AMERICANUS Wilson Found on the outside surface of the Dogfish or Bowfin (Amia calva) . This species does not appear to be very common at Lake Maxinkuckee, but possibly an examination of a larger number of fish would show different results. This is the first instance of the species having been obtained from fish in their native haunts. 3. ARGULUS MACULOSUS Wilson Found on the outside surface of the Common Bullhead (Amei- urus neblulosus), the Yellow Catfish (Ameiurus natalis) , and the *Proc. Canadian Institute (N. S.), I, p. 243. / ../. . i/,. , mi.,,, /,, , /•/,,/ l( ,,i nuil i ..•/...,.. n KM -i I • .1. , ( I ,,,/•/, .,,///. , nr, /, , | i »,,! I ,. I, ,,, ,|, |f|(1 DM ii,. i . if) . i. ..ii, . ,. hji ,,i , ,,„ , ,.,. , ,,|, llM • ' Pfl ihli pi 11 • i" •!• i ii i • N III ' iti • • "• ">i !-• i 1 '•• • " • (1ftt I II,, I,,, I ||| ||,, I,,,,,/,, ,,,,1 n, ,,l I, ,11 "" '' '• III "' ,1 | II, ,1 | |, |,|, ,| , | thl i • , ,,.,,, , . , • i in Ihi i "i -I 'I- ' >i" i) MM ' /•••-/.•.• i i il,. I • .1. . \A •/,/,,,,/,/, | i M/Ji , II,, \\ ,, ,,,,,,,11, . II,, I I,,. , ,11 I / , ,...„;. ,.,,//•./:, , II,, in iiuilii .1 i i .. i i . t i/ . .•... . .,...-.. • . i , i i,. .1 l I ,. I I , . i: , n,, , , n.. r, , , I, i / v\ kill • 'i i'^ I . I 1 """•! iliun i • • • i ""I* upon ii" 'ini i uii '• "I H, , l ,,,„,, I,,,,,! \ I,, , ,,,,,,,, It,, n, \ 'i n <''i Implli 'i i i '"•' • 11.1,1, limit , IL. ho i upon - hli i- n i> 1 i • "! • " thi 'i M "» I- • i ItWl-- ""I I ' •'•• I 'M. i U| v^ In, I, u , I),, n I, i,IU HI i ' i" r • not found «M \\\$ ,.iii, . n i, ,,, thi ' >' • \\{\\ I ' I, ,,,,,!,. ,1 .M II,. , , ,,, I,, ,| I,,, ,| ,,,., u , • non hi "||" - l\nh evei found , .1 | III \\ ,•!.! iiu, ,1 I MM., Ill, ( Ii urn, I < ,1 I <'<• I.I'M, , . ,,, III, \i, , ,,,,,, i 1 1, , thw rtl ""• tlv^lj • • "«. i, |. ,i » ii, in h M |. Whlt'l I.I, I, p U , :: i ii. iii, in loi v • ^ \\\ k< -i out "r"" ii" • • ^ n M tuiii » , |M,I.', I,, ,| ,,, V>,| | ,, \|U .i Mil , ,.,,! , Ml, ,,,,IV ,,,H|,,tM,l,,M, (,- ih, ,„,.,- I \\\ I I HUlU • I > ,11 l.UM.l' ' l • Miih,',! i;i ,, '. ( \ > IIU) Hi \\ ,11, , ,i IM. , » is u , I..M til Ml. n I' "" ' ' HI ' • ""I 'I "II" -I IHlU'l i i n ihlt'il i»i ii" i" • ' i ' Infi '• 'i - '"• H,, |WI'Hwl!l III. Ih. In I | I / I "•••• 'I tt)0< • il i I i h i Rthi ' ii mi • '!• • 'i n ' -i" i hi i MI* iii' \ M i • Euro] i i 1,1 , ,,i, h .1, 1 1 i. MI, ,i 'I'll. III. hi I.. I \ -I ll.i |>. •!'• II I "., H H, N.ll Ah, ,,,, I'M | p] 9 , I', mil- \. Ml" M <• iili i [pi ngKN w i • I -I i"" •« -I II" iMl "I Au.ru I MM I Mi I |)| ,1 1, .1 . .IIH ••! Mil lll'i'i lllllj • • oti "i H" i i !" • ill i mi ' "' tupliu i .11. |. • .1 •• hull1 In ..I- lln nl 1 1 i • I n • il- • i- • • i-i" 'i • -I- pntlltl Itti ' 'ii Illptli -i • • rii.. i. .MI- . i M. i. . I , , . II.,., , , • in 1,1 tWH (l)lllll 'I llllllllllM'll, Mil. I I •' II |. HIM Of • ! I'll' I I I M Ml!' ' llMI I' I' I I I I- 'll M |,, |, ,,,h, I 1,1 , IM ||,M liiMI I'"" "I dl I l.i'l 1)1 |.l ,,nl .,nin ,,|, I I,, n, I. • '"I "i il" bod] I I" ''I II >|i| i H" " ' ' itf of II" n,,i.|,l ,., ,1 In I ,1 , ,.,, ,1 ,.| , I ,, ,,, I, ||)| ,1 '""I < M" I 'H Ml . lull I Il , I " 1,1. Il JM Mlllllll' 'I • I" " III Mil' • I- i i i Ihi i" "i ""' • i i 'ii DI iii- i i- 1 i" !• .in , , 1 1- i. ,. i •• ,i ,i 1 1 ,.,,, ii,, , , 1 I" -I' • I I" III I i 'I. ..ul I.I II, III, ,1 I,, ,,| II,, .Ii • " 'i '" pa ti • "•' • "•! i i" i-i i • "i " • • 'i ",,i i , i i ,1,1,, MI. I H" i" HI|.|IM I....I in I I,.,. I .,1 M,, .1, . ,|, , I,. i ni I"")'" ' II" III I III. IlI'Ml Ull.l I., m, I I '. n i bi !••" ii uplli (} i ", ,I,|,IIIIM K, 'I "II- I 'i • "'I ••»• I ",• ,,, ,.|. M,, ,,ll,. , II, I, , -'" twloi thi 'i LSI -I H" 'ii • in MM i i«u« Nwlmmlntf • l>o<1ld ' •• • " thfei Ifti i In i' "i "i ' 'I" Ift] ' I I I i -In. I mil' i thi m "'mil, in.. i id. . . ui. . ,,i MI, I....I i mi I,M. .1 ,M, •.II . , II ..I .Ml. .. ul i , || ,,\\ n,, ,!.,,,,! ,, I , , I ,11, I "'" hi • lli.il -I lull < tljfj I ,1 I , I,., I I lil ' 'I I I I'l'' (A I" " "' ""< I il ml, I II,. « . i,l i ,i 1 '"'I-' •'"'! h I" I n • • II .- ' ul. .1 ,11, III' I M I thai "M. • I- i" bi I-" ring i" MI 'i i tmll M, m MI. i, iiui .,i . ,i, i H" ii food 'I "i 111 ii II i i H" • -I- i I I" ' i" i I" " Ml' I l.lu ,i ,il iur I,,, il I,., I ,u.| II,. I • ,, I I I-, ' "" ' AM Mi- i 'I ' L 0] tO f I I' bhl i' I- I- 'H i i K wwiill" • ' -I ""I ,,. I |,|,,u i i 82 Lake Maxinkuckee, Physical and Biological Survey forded in the ordinary act of breathing. Once inside the mouth and swept against the gill-arches by the out-current of water, the larva secures a firm hold by means of its powerful maxillipeds. It is noticeable in this connection that those of the Centrarch- idae which feed most persistently at the surface are the ones in- fested by this parasite. Even in the hottest weather the redeye frequents the shallow water along the shore, at least at night. As a result, its gills are practically certain to yield a goodly number of Achtheres, and the same is true of the two kinds of black bass, particularly the small-mouthed. On the other hand, a fish like the walleye, which frequents deeper water, does not present as favorable an opportunity and most of them are free from this parasite. Once fastened to the gill-arches, the parasite remains there for life, so that the only chance its enemies have to kill it are while it is swimming about freely at the surface. This free swimming period is much shorter than that of the Ergasilus and Argulus larvae, but the Achtheres larva is larger than the other two and so offers a more tempting bait. It is a signifi- cant fact that so many of them were found in the stomachs of the few minnows and darters that were examined. In this way they are kept within due bounds and prevented from multiplying in sufficient numbers to become dangerous to the larger fish. 7. ACHTHERES MICROPTERI Wright Found on the gills of Micropterus salmoides and M. dolomieu. This species is not at all common, and for a long time all the speci- mens obtained from the two basses were supposed to belong to the species ambloplitis. The female of this species, however, may be distinguished from ambloplitis by the large abdomen with its basal lobes and more distinct segmentation, and by the much smaller egg-tubes. This distinction may then be confirmed by the details of the mouth-parts. The male may be distinguished by its much larger size, and by the chelae on the tips of the second maxillae. Lake Maxinkuckee, Physical and Biological Survey 83 THE CRAWFISHES By WILLIAM PERRY HAY, Head of the Department of Biology and Chemistry, Washington, D. C., High Schools Crawfishes are quite common in Lake Maxinkuckee and in Lost Lake; on the land about the lakes they are less frequent. The truly aquatic species are found chiefly in the shallower depths, hiding under rocks, sticks, and among Chara and other aquatic vegetation. But even at their best, not as many will be taken in the seine as will be secured in similar collecting in sluggish streams. The greatest number taken in one haul of the seine in Lake Maxin- kuckee was twenty-two. In the collections turned over to me for identification and study, four species are represented, namely : Cambarus blandingi acutus, C. diogenes, C. propinquus, and C. immunis spinirostris ; or, using English names instead of Latin combinations, we may designate these four species as the Pond Crawfish, the Solitary Crawfish, the Gray Rock Crawfish, and the Rock Crawfish respectively. Of these, the first three have long been known to occur in northern Indiana, but C. int munis spinirostris has not heretofore been known north of Terre Haute. One or two other species probably occur in the Maxinkuckee region. C. argillicola Faxon, has been re- ported from several localities north, east and south of Lake Maxin- kuckee, and C. rysticus Hagen, has been taken near Mt. Etna, Huntington Co., Ind. Beyond doubt, the crawfish fauna of this lake, or of any other, will repay careful study. The habits and economic importance of these animals are only poorly known, but it must be that, as a source of food supply for other animals, or as scavengers, they fill a field of usefulness. As the present account is for the general public rather than for the zoologist, it will be unnecessary to give more concerning the structural characters of these animals than is absolutely re- quired for their recognition. The male crawfish may be distin- guished from the female by the presence of two pairs of rigid appendages which are attached to the first two joints of the abdomen or tail, and which, projecting nearly straight forward, lie in a sort of groove between the basis of the walking legs. In the female the abdomen is broader than in the male, and the appendages of the first two joints are slender and flexible like those which follow. The rostrum is the beak-like projection of the shell (or carapace) above the eyes. 84 Lake Maxinkuckee, Physical and Biological Survey 1. POND CRAWFISH CAMBARUS BLANDINGI ACUTUS (Girard) This species may be at once distinguished by the fact that in the males the third and fourth pairs of walking legs bear a hook on the third joint from the base. The rostrum is long and approxi- mately triangular, with a pair of small teeth quite close to the tip. The large pincers and the legs which bear them are long, slender, and roughly granular. This crawfish is represented in the collection by 2 males and 7 females from Aubeenaubee Creek, one male and one female from Culver Inlet, 8 males and 2 females from Spangler Creek, and by 2 males and 1 young female from Bruce Lake. This is the pond crawfish of the region, its home being in wood- land ponds. Individuals were seen from time to time but they usually escaped under the leaves. Several dead ones were found in ponds. Generally speaking, it is not a very abundant species anywhere. It is occasionally met with in the sloughs of the Mis- sissippi. 2. THE SOLITARY CRAWFISH CAMBARUS DIOGENES Girard This crawfish is an inhabitant of the lake at certain times only. It visits the water early in the spring for the purpose of produc- ing its young, but during the remainder of the year each individual lives alone in a burrow over which it constructs a chimney of mud pellets. This habit is so peculiar, being shared by only one other Indiana species, that it alone should be almost enough to distin- guish the solitary crawfish; but as some of our readers may wish to know what the animal is like the following description is given : The body is high and compressed; the rostrum is short, thick- edged, and without teeth near the tip ; the two longitudinal, curved lines on the back run together throughout the whole part of their length so that only small triangular spaces are left between them in front and behind. The color is quite brilliant for a craw- fish, the claws, rostrum, and the elevations on the shell being more or less marked with crimson and yellow. Represented by 1 large female and 7 young from Aubeenaubee Creek. Other examples were noted in 1901, as follows : March 31, a good sized female caught in a pool at the birch swamp; April 1, one dead, in ditch east of railroad, in Green's marsh ; April 2, remains of several seen in the Outlet ; April 3, remains of one found in Green's marsh; April 4, two caught, copu- Lake Maxinkuckee, Physical and Biological Survey 85 lating east of the railroad, in Green's marsh, and one caught in the marsh north of Lost Lake; April 9, three living ones seen, 2 caught, and remains of great numbers at the drained lake; April 11, one big one caught at mouth of Farrar's Creek, and one at mouth of Aubeenaubee Creek; April 15, several seen in creek at south end of the lake, 2 caught; April 17, a female with eggs caught on west side of lake; April 19, a large one dead at water's edge just east of the depot; May 3, chimneys abundant east of Lost Lake outlet; May 17, one caught at edge of Lake Maxin- kuckee at Long Point, with small young attached to it. This is a large "meaty" species with heavy pincers, and except where its natural habitat gives it a muddy flavor, makes an excel- lent food. 3. THE GRAY ROCK CRAWFISH CAMBARUS PROPINQUUS Girard This species may be recognized at once by the fact that the upper surface of the rostrum has a low median longitudinal ridge. This is too low to be visible, but may be detected by passing the tip of one's finger across from side to side, when the elevated portion may easily be felt. The species is usually an inhabitant of running water and will probably be found to occur most abund- antly about the inlets and outlets of the lake. It is represented by 15 males and 29 females from Aubeenaubee Creek, 9 males and 5 females from Lake Maxinkuckee, 7 males and 10 females from Culver Inlet, 1 male and 1 female from Outlet, and 4 males and 7 females from East Inlet. This is the common crawfish of the lake. It is found in consid- erable abundance everywhere among rocks and in the Chara. The lake form is brownish gray in color. It is too small to be of much use as human food. This species is also found in Yellow River, near Plymouth, and appears to be the most common species of the region. They do not burrow, but hide under rocks or bits of board or stick under which they may make small excavations. Of many notes taken the following may be given here: April 27, 1901, several seen in the bottom, one bluish in color; two copulating ; June 3, a large shed carapace in Outlet Bay ; June 7, several caught, they hide under boards ; one very small one with its mother; June 12, many caught, more seen, almost every blunt- nosed minnow's nest is watched by one or two; June 13, a good many at minnows' nests ; June 16, some caught at minnows' nests ; June 22, still at minnows' nests. In 1904, October 19, a common content of fish stomachs. Fisherman reports that they are "the 86 Lake Maxinkuckee, Physical and Biological Survey best bait now." One angler caught 6 black bass with crawfish and one with a minnow. October 3, many at the head of the Out- let, about 8 seen in a small space. One was eating at a dead grass pike; it stayed there a good while. October 31, one still eating in the morning at the pike. Very little of the pike eaten. No- vember 2, still eating at the pike. November 14, one near shore east of Long Point eating a minnow. November 22, two caught while copulating. November 25, two caught copulating, east of Long Point. January 1, 1905, three seen together, 2 smallish, copulating, and a big one near by. From numerous observations of the crawfishes of the lake the following conclusion may be drawn : There appears to be no special time for mating, and no special breeding period was observed; nor again, any special time for moulting. It is probable that in the fairly uniform temperature of the lake the lives of the crawfishes are not so markedly divided into seasons as they are in the river crawfishes. Generally, in rivers heavily populated with crawfishes, one can find immense numbers of moulted shells at certain periods, usually about the beginning of July, but in Lake Maxinkuckee, only occasional and scattered cast-off skins can be found. The nature of the food was not easily discovered by examina- tion of stomach contents, as the material was too finely com- minuted. A few were seen eating dead fishes as mentioned above. They are usually found in the vicinity of minnow nests, and prob- ably devour fish eggs to some extent. Various fishes, especially walleye and bass, eat them at times, and they are one of the prin- cipal foods of the soft-shelled turtle. The lake species are rarely used for bait, perhaps because of the difficulty of obtaining soft- shells or "peelers" in the lake ; river crawfishes are sometimes used. The crawfishes of the lake often have protozoa attached to the gills, but this probably does not seriously inconvenience them. 4. THE ROCK CRAWFISH CAMBARUS IMMUNIS SPINIROSTRIS Faxon In general form and appearance this species is somewhat like the last, but it lacks the longitudinal ridge on the rostrum. The teeth of the rostrum are apt to be very small and, in the males, the tips of the first abdominal appendages are slender, blade-like, and recurved. Represented by 9 males and 8 females from Aubeenaubee Creek, 1 male from Culver Inlet, and 12 young females from Norris Inlet. Lake Maxinkuckee, Physical and Biological Survey 87 By J. PERCY MOORE, Professor of Zoology, University of Pennsylvania The leeches form a fairly conspicuous part of the lake fauna. Although quite abundant, the particular forms which attack human beings do not seem to be common, and bathers are never troubled with them. In Winona Lake, near Warsaw, Indiana, which has a good deal of muddy bottom, there are places where one can not enter the water and remain long without being attacked by numer- ous leeches, the bites of which cause severe itching for days. This condition was not noted at Lake Maxinkuckee except near the Norris Inlet, where on one occasion (Aug. 1, 1906) the leeches proved very voracious and troublesome. There are probably several species present besides those listed in this paper. The long dark leech with yellowish stripes along the sides, which is usually found in soft mud, was found in Green's marsh and in the pond near the elevator. A good many fish- leeches were obtained from various fishes during the summer of 1906, and appear to be different from those to be found on turtles. Economically considered, the fish-leeches are perhaps the most important in the lake. They are especially common on catfishes, and most catfishes caught have red sore spots on the chin where the leeches have been attached. They do not appear to be abund- ant or do much harm, a single fish rarely harboring more than two or three at a time. The animals most severely troubled by leeches are the turtles, almost every one of which has one to several leeches attached. The turtle-infecting leeches are broad flat animals and "play 'possum" when disturbed. The turtles which are at liberty appear to be able to keep from being badly enough infected to do them serious injury. A snapping turtle kept in a livebox, however, was found to be badly attacked. It was fairly clean when placed in the livebox, but when taken out ten days later had a great bunch of leeches — 53 in number — attached to the neck. These leeches oc- casionally attack mussels, especially Anodontas, and are now and then found inside the mussel shell, between the mantle and the foot. A number of recently killed shells found near Norris Inlet were covered with them; they were probably feeding upon mucus. Small leeches are probably great enemies of snails, some small examples of Planorbis were found to be swarming with them. The leeches of all sorts spend a good deal of time under boards. One found June 6, 1901, under a board had a good number of round, 88 Lake Maxinkuckee, Physical and Biological Survey rather large, yellow eggs under her, and on June 8 one was found under a board covering a number of minute young. On June 11, a number of very small red ones were found attached to the mother. The swimming leech of the lake, Dina fervida, is often found under boards or rocks. When frightened it swims off with great rapidity, apparently swimming on its side with rapid dorso-ventral flexions of the body. It is pink in color and bears considerable resemblance to a fish worm in general appearance, but is flat and has no ring about the body. It does not appear to be parasitic but is a scavenger, often being found in considerable numbers on dead animals (coot, duck, shrews) found at the water's edge. They are eaten by water-dogs and probably by fishes and appear to be the principal food of the Wilson Snipe which haunt the stretches of shore during its autumnal migrations. A prominent citizen of Culver reported that leeches make the best sort of bait he ever tried. He had found this out one summer when other sorts of bait were scarce. All sorts of fish took them eagerly — bass, bluegill, sunfish, etc. They were "as tough as India rubber so the fishes could not take them off the hook — often two or three fish could be caught on the same leech." The leeches of Lake Maxinkuckee are evidently incompletely made known herein and further explorations may be expected to demonstrate the occurrence of at least five or six additional species. The collections upon which this report is based comprise 11 species. These are apportioned among three families, as follows : Glossi- phonidaB, seven; Hirudinidse, one; and Erpobdellidse, three. No specimens of the Ichthyobdellidse are included, although it is cer- tain that one and probably two, or perhaps even three, species of the true fish-leeches occur parasitically upon the skin and fins or within the gill-chambers of the small fishes of the lake. The Glossi- phonidse, as the most accessible and easily collected of leeches, are probably nearly completely represented in the collection. The same is true of the Erpobdellidse, also. Of the Hirudinidse one or two additional species of Hsemopis may be expected to occur and the true blood-sucking leech, Macrobdella decora, so ubiquitous throughout the greater part of the North American continent, should occur in the plant-grown shallows of the lake, where warm- blooded animals come to drink or where frogs deposit their eggs in the spring. For full descriptions and figures of the several species men- tioned in this report, as well as for the synonymy and literature references, the following papers may be consulted : Castle, Some Lake Maxinkuckee, Physical and Biological Survey 89 North American Fresh-water Rhynchobdellidse, Bulletin Museum of Comparative Zoology, Vol. XXXVI (1901), pp. 16-64; Moore, The Hirudinea of Illinois, Bulletin Illinois State Laboratory of Natural History, Vol. V (1901), pp. 479-547; Nachtrieb, Heming- way & Moore, The Leeches of Minnesota, Geological and Natural History Survey of Minnesota, Zoological Series, No. V, 1912, es- pecially Part III, Classification of the Leeches of Minnesota. For the determination of the species herein listed the following Key will serve: A. Mouth a small pore through which the slender exertile pharyngeal pro- boscis may be protruded ; complete somites usually composed of three rings, one or more of which may be partially subdivided. Glossiphonidse B. Eyes all simple, one to three pairs, those of the two sides usually dis- tinct; form slightly or moderately depressed; cutaneous papillae few and mostly small or obsolete; gastric caeca small and simple or little branched, sometimes reduced or absent; no compact pharyngeal glands. Glossiphonia C. Eyes one pair, widely separated; genital orifices separated by one an- nulus; gastric caeca more or less reduced, size small. (Subgenus Helob- della.) 1. A brown or yellow cuticular nuchal plate and underlying gland on dorsum of somite VII; color pale pink, gray, brownish or greenish; gastric caeca three to six pairs, the first two or three pairs always small; usual length 10 to 15 mm.; slender. G. stagnalis 2. No nuchal plate or gland in adult; more or less heavily pigmented with brown in longitudinal lines with metameric white spots on middle annulus of complete segments; generally three longitudinal series of papillae conspicuously pigmented with dark brown or black; gastric caeca five or six pairs ; length of G. stagnalis but stouter and more depressed. G. fusca CC. Eyes three pairs; genital orifices separated by two annuli; gastric caeca not reduced, six or seven pairs. (Glossiphonia ss.) 3. Eyes in regular longitudinal series; a pair of dark longitudinal para- median lines above and below; opaque; length 15 to 25 mm.; robust. G. complanata 4. Eyes grouped in twos at the angles of a triangle; translucent and little pigmented, no dark longitudinal lines; length 6 to 12 mm.; broadest and most depressed of genus. G. heteroclita BB. A single pair of compound eyes, often united into a common pigment mass and rarely followed by several pairs of simple eyes; form moder- ately or greatly depressed; cutaneous papillae usually numerous and con- spicuous; gastric caeca seven pairs, large and more or less complexly branched; a pair of compact pharyngeal glands in addition to the dif- fuse salivary glands. Placobdella D. Somites I-V much widened to form a distinct head; form little depressed. 5. Dorsum bearing three prominent papillated keels; color usually green or olive; length rarely exceeds 20 mm. P. montifera 90 Lake Maxinkuckee, Physical and Biological Survey DD. No distinct enlargement of anterior segments to form a head; form greatly depressed, foliaceous. 6. Integuments rather opaque; colors in a bold pattern of yellow and olive green or brown; dorsal papillae low and smooth; length up to 3 inches. P. parasitica I. Integuments translucent; colors a much broken pattern of mixed yellow, brown and green; dorsal papillae very numerous, elevated and rough; length up to 2% inches. P. i~ngosa A A. Mouth large; pharynx without protrusible proboscis; complete somites usually of five annuli, some of which may be subdivided. E. Pharynx usually provided with three distinct toothed jaws; testes several metameric pairs; eyes five pairs in as many segments. Hirudinidx 8. 12-16 pairs of coarse teeth on each jaw; genital orifices separated by five annuli, penis filiform; color usually a mottled pattern of black or brown and gray, sometimes plain dark green or yellow; usual length 3-5 inches. Hxmopis marmoratus EE. Pharynx provided with three longitudinal muscular folds but no toothed jaws; testes numerous and minute, not metameric; eyes usually three or four pairs in two groups. Erpobdellidse F. Last annulus (b 6) of each somite not obviously enlarged or subdivided. Erpobdella 9. Genital orifices separated by two rings ; eyes three pairs ; color usually two or four dark longitudinal stripes separated by paler bands; loops of vasa deferentia reaching to ganglion XI; length about 2-3 inches. E. punctate, FF. Annulus b 6 obviously enlarged and subdivided. Dina 10. Genital orifices separated by two rings; eyes three or sometimes four pairs; pigmentless or dorsum marked with irregular scattered spots; vasa deferentia not reaching ganglion XI; length 1 to l1/^ inches. D. fervida II. Genital orifices separated by three and one-half (sometimes three) rings; eyes four pairs; pigmentless or more usually with numerous small, often confluent, dark spots, sometimes forming a median stripe; vasa deferentia as in 9; length seldom in excess of 1 inch. D. parva GLOSSIPHONID^E 1. GLOSSIPHONIA STAGNALIS (Linnreus) This almost cosmopolitan and usually very abundant species is very poorly represented in the collection by twenty-two speci- mens from three localities. In the small meadow ponds and shal- low lakes that abound throughout the northeastern United States and contiguous portions of Canada this species occurs in great numbers. It also occurs in the warm shallow waters of creeks and rivers, especially in quiet bays overgrown by aquatic vegetation. These leeches shun the bright light and congregate in great num- bers under stones and the ensheathing foot-stalks of the leaves of rushes, Sagittarise, etc. Lake Maxinkuckee, Physical and Biological Survey 91 The most usual food consists of small annelids, insects and mollusks but blood will be taken from abraded surfaces of all kinds of living and dead animals whenever opportunity offers, and for this purpose vast numbers of these little leeches gather about fishing stations where the bloody offal is thrown into the water. In turn they form no inconsiderable part of the food of certain of the larger leeches and of small carnivorous fishes, and, along the shores of tidal rivers, of snipe and sandpipers. Like other species of the same family this leech carries its eggs and young attached to the ventral surface of the parental body, the margins of which are inrolled, especially when disturbed, to make a crude sort of temporary brood chamber. Before hatch- ing, the eggs are enclosed in groups in small mucoid sacs, of which each leech may bear from eight to fifteen. The following are the labels attached to the Lake Maxinkuckee specimens: "Long Point, under stones, Dec. 7, 1904," 1 speci- men with G. complanata; "E. side knee-deep, Sept. 17, 1906," 20 with G. fusca ; "19-I-III," one with G. complanata, G. fusca and G. heteroclita. 2. GLOSSIPHONIA FUSCA Castle This pretty little gray leech was taken at a greater number of stations and is probably more plentiful in Lake Maxinkuckee than the last. This might have been anticipated as it is generally more partial to colder and clearer waters than is G. stagnates. It is a true snail-leech and, being much more sluggish than G. stagnalis, confines its attacks almost exclusively to the smaller aquatic species of these mollusks. In breeding habits this species resembles the next to be described. "E. Long Pt., by Holbrunner's, Oct. 29, '04", 1 specimen with G. complanata and a small Placobdella rugosa; "Long Pt. Nov. 1, '04," one small example; "Long Pt. Dec. 7, '04, under stones," one with seven G. complanata; "E. side knee-deep, Sept. 17, 1906," 2 with twenty G. stagnalis; "19-I-III," one with G. complanata and G. heteroclita. 3. GLOSSIPHONIA COMPLANATA (Linnaeus) This well-known species is widely distributed throughout Europe, Asia and North America and is very constantly character- ized everywhere by the arrangement of the eyes and the pair of longitudinal dark lines above and below. In the Lake Maxin- kuckee collections it is the most generally represented of its genus. The common name of snail-leech given to this species in Eng- land is equally applicable here as its principal food consists of 92 Lake Maxinkuckee, Physical and Biological Survey small water snails which its great relative strength enables it to overcome with ease. Small worms and aquatic insect larvas are also eaten but it rarely or never partakes of the blood of verte- brates. Notwithstanding its great strength and activity when once aroused this is naturally a sluggish leech and is much more likely than other related species to roll itself into a tight ball and so remain quiescent for considerable periods of time. The breed- ing habits closely resemble those of the last species, especially in the fact that only a small number of capsules, each containing a large number of eggs, are produced. The length of the breeding season is also unusually long. "Aug. 18, '00, B. W. E.," 1 specimen; "Long Pt. Sept. 1, '00, with five other sorts," one unusually large example; "E. Long Point, by Holbrunner's Oct. 29, '04," three specimens with the brown lines broken into series of dashes, with one G. fusca and one P. rugosa; "Long Pt., Dec. 7, '04, with others," four small ex- amples; "Long Pt. Dec. 7, '04," 8 small specimens with G. fusca and G. stagnalis; "E. side knee-deep, Oct. 17, '06," 4 specimens one of which is coarsely mottled on the dorsum; "19-I-III," 1 speci- men with one each of G. stagnalis, G. fusca and H. heteroclita. 4. GLOSSIPHONIA HETEROCLITA (Linnaeus) This is a small leech of very distinctive characteristics which occurs in Europe and the northern United States. Nowhere in this country is it plentiful though it is probable that it is frequently overlooked because of its small size and inconspicuous coloration. Little is known of its habits. It is found in the same situations as G. stagnalis and is very sluggish. Its usual food appears to be the juices and mucus of aquatic snails. Unlike the remaining species of the genus, the eggs are attached singly to the ventral surface, more as in Placobdella. But one specimen occurs in this collection, "19-I-III" with one each of G. stagnalis, G. fusca and G. complanata. 5. PLACOBDELLA PARASITICA (Say) This strikingly handsome leech of interesting habits is not only one of the most abundant but one of the largest and best known of our North American species. it is familiar chiefly as a temporary blood-sucking parasite of the snapping turtle but occurs more rarely upon other species of aquatic turtles, and also lives during part of its life a free existence during which it feeds on aquatic worms and other small inverte- brates. The method of fertilization by means of spermatophores Lake Maxinkuckee, Physical and Biological Survey 93 attached to the skin, and the habit of carrying the eggs and young are very interesting but have been frequently described. This is the largest of the Glossiphonids of the United States, the giants of the species attaining a length of four inches and a width of one inch. Abundantly represented in the collection from the following stations : "July 18, '00, B. W. E.," one specimen; "Nov. 30, '00, picked from a snapping turtle," numerous specimens presenting much variation in color pattern, some of them bearing young or attached spermatophores ;" "musk turtles, April 10, '01," two small ; "Outlet Bay, under board, June 12, '01," four specimens with P. rugosa; "Outlet Bay, Nov. 26, 1904 (13-2)," 1 specimen; "on painted turtle, between Lakes Lagoon, Dec. 19, '04," five specimens, one of which bears young ; "near Inlet, in Chara, 4-5 ft., Dec. 24, 1904," 1 speci- men ; "back of snapping turtle, Aug. 28, 1906," one large and three smaller examples; "Outlet, Aug. 10, 1906," one; "Oct. 29, 1906", three specimens "on shore on dead turtle and shrew." 6. PLACOBDELLA RUGOSA (Verrill) This large species is readily distinguished in its ordinary phases from the preceding by its very rough and translucent in- teguments and its much broken, mixed color pattern in which brown usually predominates. Although sometimes associated with P. parasitica on turtles it is usually free-living and inhabits the muddy shallows of warm streams and ponds where it is found abundantly attached to the under surface of driftwood or stones. The ordinary food consists of worms, insect larvaa and other aquatic invertebrates but blood will also be freely taken. The eggs are carried in early spring in a layer attached to the underside of the leech and covered by a delicate membrane. When with eggs the parent usually attaches itself firmly by both suckers to the under surface of a stone or other firm object and resists removal vigorously. When removed the eggs will frequently be found ad- hering to the foreign object. "Nov. 30, '00," four specimens ; "Outlet Bay, under board, June 12, '01", four specimens with P. parasitica; "leeches from Kinoster- non odoratum, Apr. 19, 1901," 2 small; "E. Long Pt., by Hol- brunner's Oct. 29, '04," one small specimen with G. fusca and G. complanata; "Long Pt., Nov. 1, 1904", three with attached sper- matophores; "snapping turtle's back, July 28, 1906", two small specimens; "III, 1 H. W. C. 19," one; "III, 1 H. W. C. 19-7," 2 small. 94 Lake Maxinkuckee, Physical and Biological Survey 1. PLACOBDELLA MONTIFERA Moore This species is easily distinguished among the present assem- blage by the enlarged head disc and strongly keeled back. It is a solitary leech whose habits are still imperfectly known. Al- though often found under stones and among plants in shallow brooks and ponds it is a voracious blood sucker and in pursuit of its food attaches itself frequently to frogs, toads, mussels and snails. A single small specimen from Long Pt., Dec. 7, 1904, under stone. HIRUDINID^E 8. H^EMOPIS MARMORATIS (Say) Along with P. parasitica this was one of the first leeches to be described from North America by Thomas Say. It is widely known as the horse leech from its habit of living in the mud of pasture drinking holes and attacking horses and cattle that come to its haunts to slake their thirst. It also occurs along the shores of rivers and lakes where it burrows in the mud in search of earth- worms, smaller leeches, insect larvse, various small mollusks, etc., which constitute its usual food. Its eggs are laid in a mass of albuminous mucus enclosed in a horny capsule and deposited in the mud. This, the only species of Hirudinidse represented in the collec- tion, was taken at two points only : "Long Pt. June 2, '01," one specimen ; "Green's flat, Apr. 3, '01," two small. ERPOBDELLID;E 9. ERPOBDELLA PUNCTATA (Leidy) A generally very abundant species of fairly wide distribution, well known for its variability, its activity and its ferocity. It feeds upon all kinds of small aquatic invertebrates, not excepting leeches of its own and smaller species, sucks the blood of vertebrates whenever opportunity offers, and is a great scavenger, collecting in great numbers wherever waste from slaughter houses is deposited in streams, and on the shores of ponds upon which the prevailing winds drive dead fishes and other animals. The egg capsules are well-known chitinoid flattened capsules attached to the under sur- face of stones, etc. "July 5, '99," one unspotted pale specimen ; "Outlet Bay, 1901," one small; "Long Pt., Nov. 1, '04, with others," several with D. parva and D. fervida. Lake Maxinkuckee, Physical and Biological Survey 95 10. DINA FERVIDA (Verrill) A species mainly characteristic of the lake region of the north- ern United States and southern Canada, represented in the collec- tion from several points. The habits so far as known are essen- tially similar to those of E. punctata. "Nov. 30, '00," eleven specimens ; "Long Pt., Nov. 1, '04," sev- eral with D. parva and E. punctata, two have four pairs of eyes like Verrill's type; "near Outlet, Dec. 13, 1904," two specimens; "near Inlet, in Chara, 4-5 ft., Dec. 24, 1904," two specimens ; "near Inlet, Dec., 1904", two. 11. DINA PARVA Moore Little is known of this species, which was first taken in Minne- sota and appears to be abundant in Lake Maxinkuckee. Nothing is known of its habits. "Long Pt., Nov. 1, '04, with others," many specimens with D. fervida and E. punctata; "Long Pt., Dec. 7, 1904," a large num- ber, most of which are pigmented; "on shore on dead turtle and shrew, Oct. 29, 1906," numerous small specimens. THE PROTOZOANS AND CCELENTERATES No special attention was paid to the Protozoa of the lake ; only those forms were noted which thrust themselves upon our notice. The protozoan life of the lake is not conspicuous except for a few forms which are found in such abundance as to attract atten- tion. The list of species identified is a short one, not because these organisms are rare at the lake, but because no one of the party en- gaged in the study of the lake was especially interested in or fa- miliar with them. An attempt was made to collect and preserve all forms that attracted the attention, but these were naturally only a small proportion of the species present. It so happened that the plankton, which should have contained a number of these or- ganisms, was submitted to two different experts, one interested in Algae, the other in Crustacea, with the result that such Protozoa as there were went by default. Forms of doubtful affinity, by some placed among Algse and by others as animals, such as Peridinium, Ceratium and Volvox, are included, Volvox especially exhibiting characters which strongly suggest a position in the animal series. Following are our notes upon the few species identified: 96 Lake Maxinkuckee, Physical and Biological Survey 1. ARCELLA VULGARIS Ehrenberg Upon examining the stomachs of a number of tadpoles caught at the edge of Aubeenaubee Bay in August, 1906, a goodly num- ber of Arcella vulgaris were obtained. The tadpoles when caught were busy sucking the surface of weeds and sticks, as is their habit, and from these they probably obtained the Protozoa. It is probable that Protozoa form an important part of the food of young tadpoles. On other occasions we have seen them taking in large numbers of Paramo2cium. Arcella vulgaris was abundant September 3, 1906, with other material (Paramcecium) forming a scum over water in a tumbler where some duckweeds were kept. It was also present in hand- gathered material obtained at the dam in the Outlet, October 30, of the same year. 2. CENTROPYXIS ACULEATA Stein Taken occasionally in the summer and autumn of 1906 in gath- erings in shallow water near shore. 3. EUGLYPHA ALVEOLATA Dujardin Obtained in collections near shore, summer and autumn of 1906. 4. DINOBRYON sp. Found occasionally near shore in Lost Lake, but not abundant. In the small lakes about St. Paul, Minn., where it is very abund- ant, it furnishes an important item in the food of the fresh-water mussels. 5. EUGLENA VIRIDIS Ehrenberg Some found in a scum in pools in Green's marsh. The great amount of vegetation makes the water almost as rich as an in- fusion. Obtained August 22, 1906. Euglena formed a bright green scum over the small pools. 6. VOLVOX AUREUS Ehrenberg Not found by us at all in the lake, but exceedingly abundant in Farrar's pond and a pond east of the lake in the spring of 1901, large swarms being seen there, a single dip of a common dipper al- ways containing several examples. A large number of examples obtained from a small pond near the lake April 24, 1901. Its favorite habitat is shallow pools, easily warmed throughout and containing in the bottom an abundance of dead leaves or similar fertilizing matter. This species was exceedingly abundant in the shallow well-fertilized carp ponds at Washington, D. C., in the spring of 1906. Lake Maxinkuckee, Physical and Biological Survey 97 7. PERIDINIUM TABULATUM Ehrenberg Taken rather less frequently in the vertical hauls than its rela- tive, ^Ceraimra macroceras, and apparently not very common. One might naturally expect it to be more common near shore. It was not noted often in surface hauls. It is a species of world-wide dis- tribution, and probably is abundant where conditions are favorable. There is very little difference between the genera Ceratium and Peridinium, the horns or projections, which are the distinguishing characteristics, occurring in all degrees of development. 8. CERATIUM MACROCERAS Schrenk Common in the vertical plankton hauls, occurring in the great majority of hauls, but not common in the surface towings. A similar form, C. tripos, was collected in towing near shore at Eagle Lake. The long horns or projections of this species are de- veloped perhaps as much to give buoyancy to the form as for pro- tection. The Peridinales, represented by this and the 2 preced- ing species, are claimed by both botanists and zoologists. 9. STENTOR CCERULEUS Ehrenberg While raking up weeds through a hole in the ice at the Weed- patch, January 15, 1901, it was noted that the water dripping from the plants turned the snow a vivid green. The snow thus colored was taken home and examined and the green color was found to be due to multitudes of green stentors. These were kept in a vessel for some time. On January 6, they began to gather on sticks, on snail shells, on the sides of the vessel, and on the under surface of the water, assuming a globular form. The species was probably cceruleus. On February 7, on looking through the ice on Outlet Bay, it seemed full of a reddish fine material like stirred up mud. Exam- ination revealed the presence of small diatoms and many green stentors. 10. STENTOR sp. Among our notes mention is made of another Stentor, larger than the green one, brownish and with a large, flat, peristomal disc, circular, with a side cleft like a water-lily leaf. On October 14, 1907, it was noted that brown stentors were at- tached to the under side of lily-pads in Hawk's marsh. 11. VORTICELLA CHLOROSTIGMA Ehrenberg On June 26, 1901, white, fluffy little globules which shrank to minute size when touched, and which proved upon examination 7— 17618— Vol. 2 98 Lake Maxinkuckee, Physical and Biological Survey ' to be composed of colonies of Vorticella, were found very abundant on the submersed tips of Ceratophyllum leaves at the Inlet. Late in the autumn of 1904 (October 81, November 2 and 16), the ^ame objects were noted, but in considerably longer and larger patches, on various weeds, such as Myriophyllum, etc., in the vicinity of Winfield's. Again, in the autumn of 1906, they were exceedingly abundant in various weeds, especially dying leaves of Vallisneria, in Outlet Bay. So far as we have observed, these organisms seem to increase greatly during the autumn. Both white and green colonies were found, alike in everything except color, and it is probable that they were the same species under different condi- tions. The green forms showed distinctly against the dead Val- lisneria leaves, which had faded to a papery white. It may be it was common during the summer, but concealed by its green sub- stratum. June 22, 1906, it was plentiful on the weeds in Lost Lake. In a note of June 26, concerning this species occurs the remark : "This is a larger sort; there are also other smaller isolated ones present." On July 25, and previously, it was common in both lakes in weedy, stagnant places, forming a white halo along stems, not in balls. In addition to these there are minute green Vorti- cella-like organisms attached to the parasitic copepods on the gills of fishes, and on August 28, 1908, a number of minute clear Vorti- cellas were found on the body of a Cyclops. A species of Vorticella was abundant July 31, 1906, on Anabasna in plankton scum. Small Vorticellas are found in myriads on objects in Hawk's marsh. They can be found there more abundantly than anywhere else about the lake. 12. EPISTYLIS sp. A species of Epistylis, probably plicatilis Ehrenberg, was ob- served forming a dense growth on the shells of a small Planorbis, March 25, 1901, near Chadwick's pier. The copepods of the same region at that time presented a very fuzzy appearance, and upon examination were found to be thickly overgrown with the same or a similar protozoan. 13. OPERCULARIA IRRITABILIS Hcmpel Abundant during the summer and autumn of 1906, upon the lower surface of the shell (plastron) and also on the skin of various turtles, especially the painted and snapping turtles, making a close, short, brown, fuzzy growth. The turtles were botanic gardens above and zoological gardens below. The organisms seemed to do Lake Maxinkuckee, Physical and Biological Survey 99 them no injury, and were gotten rid of when the turtles shed their scutes. It sometimes forms a halo about the heads of small turtles, in which case it was at first mistaken for Saprolegnia. It is usually the head of the Musk Turtle that is affected. In this case it ap- pears to do no harm, as the turtles are quite lively. Something very like this, probably the same thing, was ob- served abundantly (August 6, 1907) on the shoulders of a dragon- fly larva. 14. VAGINICOLA sp. A species of Vaginicola, perhaps gigantea, was rather common along the shore of the lake by Overmyer's hill, attached to algaB, October 28, 1906. There were at least 6 examples on one small bunch of alga?. The sheath was brownish and transparent. When jarred, the animal retracted into the sheath, usually doubling up somewhat into a sigmoid curve. 15. TOKOPHRYA QUADRIPARTATA ((Xeparede & Lachmann) Common, intermixed with Opercularia irritabilis, on the ventral scutes of a Musk Turtle, September 12, '1906. It was also found to some extent of the back. 16. OPHRYDIUM sp. By far the most abundant and conspicuous protozoan in the lake was a species of Ophrydium which formed large blue-green gelatinous colonies about the size of a hazelnut, or larger. These semitransparent blue-green balls remain in about the same condi- tion the year round. They are found abundantly wherever the carpet chara grows, and are usually attached to it or to pebbles; or, quite frequently, to mussel shells either alive or dead. Clear colonies, remarkable for their unusual transparency, were found on submerged pieces of tile, August and September, 1907. At cer- tain times, as August 1, 1906, and August 1 and October 12, 1907, great quantities are washed ashore. The colonies are sometimes hollow, as were many of those washed ashore August 1, 1907. 17. HYDRA OLIGACTIS Pallas Not frequently encountered in the lake. On October 81, 1906, however, multitudes were found under leaves at the water's edge on the east side, and on November 13 more were found in a similar position. November 18 one was found attached to floating Wolf- fiella in Norris Inlet. 100 Lake Maxinkuckee, Physical and Biological Survey THE WORMS Our notes on this group are few and very unsatisfactory. We give here only such of them as may possess some value. The attention we were able to give to these forms was so little that we are unable to say much regarding their relative or actual abundance, their distribution, or their relation to the biology of the lake. Flat- worms or Planarians, small, soft, flat objects, gray above, white below, and oval in outline, were common on rocks and among weeds in the lake. In certain material (Vorticella, etc.) obtained near Norris Inlet, they were quite common. They were often abundant on Ceratophyllum also. They were so soft that they often pulled apart when attempts were made to remove them from the rocks. Small pinkish parasites (probably a species of Distomum), re- sembling minute leeches, were found quite common in the stom- achs of fishes, particularly the Straw Bass (Micropterus salmoides) and the Skipjack (Labidesthes sicculus) . Usually during the winter the stomachs of .these fishes contained little or no food, but in most cases from one to several of these parasites were found in each. Round-worms, resembling Ascaris, are frequent intestinal para- sites of the snakes of this region, and one small form was found in the intestine of a mussel. Tapeworms were almost invariably present in the several shrews (Blarina brevicauda) examined. They were also common in the yellow perch and walleyed pike, and practically every dogfish (Amia calva) examined was heavily loaded with them. Many duck stomachs examined, especially those of the ruddy duck, contained from a few to many tapeworms. Angleworms or fish worms are not abundant in this region. The country about the lake is chiefly sandy, a soil not favorable to angleworms. At the edges of ditches, marshes and woodland ponds, where the soil is a black loam with some admixture of clay and decaying vegetation, a rather small species of Lumbricus is fairly abundant. Fishermen who know these places are usually able to secure all they need for bait. The farmers and farmers' boys and the boys of the village are the ones who make most use of fishworms in their angling. On December 7 (1904), worms which resembled angleworms were observed in considerable numbers coiled up under a sub- merged water-soaked board at Long Point, where they evidently were passing the winter. These worms, however, possessed no Lake Maxinkuckee, Physical and Biological Survey 101 annular ring. In alcohol they display a fine opalescent iridescence in reflected light. One seemed to be dividing by a constriction near the middle. Some very small worms, resembling fishworms in general ap- pearance when alive, were seen at the mouth of a ditch April 19 (1901). Cotylaspis insignis Leidy is a common parasite of the mussels of Lake Maxinkuckee and Lost Lake. To the naked eye this para- site looks like a minute yellowish leech. Its position in the mussel is close up in the axils of the gills. It was found in Lampsilis luteola and also in Anodonta grandis footiana, from one to several being found in nearly every example of these species examined Au- gust 28 (1906). It was also found in mussels taken on September 28 following, in Little River near Fort Wayne. The so-called Horsehair Snake or worm (Gordius sp.) is very abundant in and about Lake Maxinkuckee. According to anglers, many of the grasshoppers used by them for bait are infested with this parasite. On August 2 (1906), large numbers were seen writhing about in mud among snails along the Outlet where it had been suddenly lowered by a dam at the railroad bridge. We sus- pect that they may be parasitic in this snail also. They were frequently found in fishes, either free in the lower intestine or coiled up and encysted in some of the internal organs. The bluegill appears to be especially liable to infection by Gordius. It may be that the fish become infected through the grasshoppers they devour. On August 6 (1906), these worms were noted in con- siderable numbers in shallow water on the east side of the lake. A long slender brownish worm, probably a species of Tubifex, was found in considerable numbers projecting up into the shallow water from the soft mud bottom of Lost Lake. These were first observed June 8 (1901), when the bottom near the shore was seen to be covered with small whitish mounds about the size of buck- shot, which gave a peculiar mottled or dappled appearance. When some of this mud was dipped up and examined the small mounds were seen to be small sand tubes in which the worms were and from which they waved about in graceful undulations. They were observed again at the same place on June 15. On June 18, many were seen in the creek under the railroad bridge and on June 25, some were noted at the south end of Lake Maxinkuckee. And finally, on November 4 (1904), numerous burrows were seen in shallow water near shore in Lost Lake. Thorn -head worms (Acanthocephali) were found to be common intestinal parasites of various fishes and turtles. Among fishes 102 Lake Maxinkuckee, Physical and Biological Survey the redeye appeared to be most affected. The carnivorous turtles such as the soft-shelled and the snapper were especially subject to them while the herbivorous species, particularly the painted turtle, were comparatively free. Record may here be made of a Bryozoan, Plumatella poly- morpha, possibly related to the Gephyrean worms. Plumatella polymorpha is a compound animal, many individuals budding off from one another, as in plants. The moss-like colonies of this species were very common in the lake among the Chara and other plants. They were noted in the Chara near the depot pier, off Long Point, near Winfield's, and at the south end near the Farrar cottage. Indeed, it appears to be distributed generally through the lake wherever there are patches of vegetation. Among the Charas it forms a brown upright bushy growth. In the Weedpatch it was common on the leaves of Potamogeton amplifolius. On Oc- tober 23 (1900), it was found to be abundant on Ceratophyllum in rather deep water. A week later (October 29) a good deal was gotten on Myriophyllum. Early in the spring (March 1, 1901), it was seen growing on Potamogeton robbinsii, and a little later it was found in abundance in front of Arlington station. It was often found on Chara and other aquatic plants dredged at various times. It was also found growing on tile piles September 1 (1906). During the autumn of 1900, the statoblasts were frequent in plankton scum along shore, often being present in great abund- ance. They somewhat resemble floating sand grains but are lighter in weight, being minute circular brown discs uniform in shape and size. Under magnification they show series of facets like the compound eye of insects. On October 18 (1900), one of the buoys which had been for some time anchored out in the lake was found to be covered with a flat creeping growth of this species. As Plumatella polymorpha occurs in this lake it is highly worthy of its specific name, as it shows great variation in form and general appearance. The leaves upon which it grows are often eaten by fishes, prob- ably for the sake of the Plumatella. The yellow perch and bluegill are the species in whose stomachs we found it most abundantly. The stomach of a bluegill caught at the Weedpatch October 26 (1904), was full of statoblasts. During the autumn of 1904 it was noted as exceedingly abundant. So far as we know Plumatella polymorpha is the only Bryozoan in this lake. Lake Maxinkuckee, Physical and Biological Survey 103 THE SPONGES Sponges are not especially abundant in the lake. In some of the not far distant lakes, as Winona Lake, they frequently form a thick coating around the submerged portions of bulrushes grow- ing out in the water, but at Lake Maxinkuckee this was not ob- served. They are not common on the rocks. On September 9, 1906, some were found forming a coating on submerged rocks on the east side and some of these were collected a few days later. On November 5, 1906, some flat ones found on rocks on the east side were apparently being eaten by insect larvaa. On September 22, 1907, Prof. U. 0. Cox of the Indiana State Normal, found some flat sponges covering a rock where the lake enters the Outlet at the wagon bridge, and there were more on a rock farther down be- tween the wagon and railroad bridges. This completes the rec- ord for the flat sponges. A long, green string-like form found hanging among the weeds at the lake, especially at the Weedpatch, was much more com- mon. This was observed quite frequently and often obtained when collecting aquatic plants. Occasionally, these long strings were washed up near shore. On October 27, 1900, these sponges were observed forming statoblasts on the weeds in Lost Lake. Occasionally, the sponges form small, blue-green, spherical masses, like bullets, around the stems of Chara. On January 22, 1901, some of these spherical sponges were observed on carpet chara about 5 feet out from the Arlington Hotel. Sponges are quite common in creeks and ponds near the lake. The long form is common in Twin Lakes. There are long, finger- like forms in Yellow River, and they were abundant in the Outlet about the bridge below Walley's. The sponges were submitted for identification to the late Mr. Edward Potts, of Media, Pa., who in a letter dated May 24, 1905, wrote so interestingly regarding the material that we here quote his letter in full : Yours with package of material was received by first mail yes- terday A. M. ; and having nothing important on hand, I examined the vials at once, with the following results : First, I must express my pleasure in finding that you had sent only Sponges; that is, remembering that frequently even workers in other lines of science are utterly unfamiliar with these forms, and hence send one gelatinous and otherwise incongruous articles, I was glad to learn that you know a sponge when you see 104 Lake Maxinkuckee, Physical and Biological Survey it. The only possible exception is in your No. 5, which as you supposed, is not a sponge but only a puzzle, which may perhaps be explained by considering the fibres to be a form of alga, or more probably, the stems or stipes (as the "Micrographic Dictionary" calls them) of some, possibly all, those Diatoms now found at the outer surface of the sub-spheres. I have frequently found Dia- toms so growing. No. 1 is Carterius tubisperma Mills, and is, I am sorry to say, the only sponge in satisfactory condition for safe determination. Nos. 2 and 4 are, I fully believe, of the same species as No. 1, and they have plenty of gemmules or statoblasts; but these are so far from maturity that, if the same species, the chitinous coat is ex- tremely thin and it apparently has not yet developed the foraminal tubules, the granular crust, and protective bisotulate spicules which should be the determining points. I do not understand why this should be so with the date given (Nov. 15 and later) ; but I suppose it possible that cold spring water or its unusual depth may have re- tarded development to a date later than that with which I have been familiar. This is further suggested by No. 3 in which I have failed to find any gemmules and which reminds me of the appear- ance and condition of forms that I have sometimes called perennial or evergreen sponges, which apparently continue their growth all through the winter, at least in deep water .- No. 3 is clearly a different sponge from the others, as shown by its shorter and more robust spicules (skeletal) which, as you will see, are covered with very minute spines. I should have been much pleased to find the statoblasts of this sponge. The skeleton spicules suggest Meyenia leidyi Carter, although in that species they are rarely microscopical. You may meet with it again under more favorable circumstances.3 Although I fear they are too soft for safe transportation, I pro- pose to pack with the vials returned, two trial slides, No. 1, show- ing Carterius tubisperma in which you may see the foraminal tubules before mentioned and the armature of radial birotulate spicules, beside the skeleton and derma Is; and No. 2, showing sepa- rated spicules of the same. 2 See my Monograph, pp. 245, 246. 'See fig. 1, plate X, of my Monograph. Lake Maxinkuckee, Physical and Biological Survey 105 THE PLANKTON By CHANCEY JUDAY, University of Wisconsin Between the 2nd and the 29th of August, 1899, some observa- tions were made on the plankton of Lake Maxinkuckee as a part of the field investigations of the U. S. Fish Commission at that lake. The net used in making the observations had an opening of 471.5 sq. cm. The filtering cone was made of Dufour's No. 20 bolting cloth. The area of the cone was 3,910 sq. cm., thus making the ratio of the opening of the net to filtering area 1 to 8.2. Lack of time prevented experiments for the determination of the coeffi- cient of the net, as the plankton work was only one of several duties assigned the writer. Three main stations were selected. No. I was located just north of the center of the lake in the deepest part. No. II was in the southwestern part in a small basin called the Kettlehole. This basin has a maximum depth of 43 feet (12.8m.) and is separated from the main basin of the lake by a considerable area where the water scarcely exceeds 10 feet (3m.) in depth. During the time of these observations, the bottom temperature in the Kettlehole was lower than the bottom temperature in the deepest part of the lake. This was selected for the purpose of determining whether these local peculiarities would have any marked effect on the quan- tity of plankton. No. Ill was about midway between the other two stations in water only 20 feet (6m.) deep. For purposes of comparison in horizontal distribution, one series of hauls was made at each of five other stations. In making the hauls, the net was lowered to the desired depth and then raised to the surface with a velocity as nearly uniform as possible. The material was washed into the bucket of the net and then transferred to 95 per cent, alcohol. Because of the small amount of time available for this work,' the centrifuge method was used in measuring the quantity of plankton. This method, however, is open to the serious objection that the material is treated as if it were a homogeneous mass, and this is obviously not the case. This same objection applies equally to the gravity method, in which the material is allowed to settle a certain number of hours. Both must be supplemented by the counting method in order to show the part played by each species in the plankton life of a body of water. In settling the material, the centrifuge was given a speed of 3,000 revolutions per minute and this speed was continued for a period of one minute. 106 Lake Maxinkuckee, Physical and Biological Survey In all, 128 hauls were made at the principal stations. Not all of them are included in the following tables, however, as some hauls were made at depths not regularly included in each set of observations. Their omission does not affect the conclusions in any way. The tables show the quantity of plankton in cubic centi- meters under each square meter of surface and to the depth indi- cated, exclusive of a correction for the coefficient of the net. That is, they show the total quantity taken in each haul multiplied by 01 r>(l^\ 4l.4\lll 5). In the results given for Station I, those for the first, second, and fourth weeks are averages of three to five sets of observations per week but only one set was made the third week. At Station II, only one series of hauls was made each week. At Station III, no hauls were made the first week and only one set each during the second and third weeks. The result for the fourth week is the average of ten sets of hauls. STATION I Depth First week Second week Third week Fourth week 0—1 m. 34.55 23.85 22.26 18.65 0—3 m. 43.88 37.73 30.21 27.77 0—5 m. 49.50 47.27 38.70 31.67 0— 8m. 65.40 56.18 50.35 39.58 STATION II Depth First week Second week Third week Fourth week 0—1 m. 29.68 22.26 19.08 15.90 0—3 m. 37.10 84.45 25.44 23.32 0—5 m. 50.88 41.34 30.21 32.33 0—8 m. 56.18 54.58 34.98 31.80 STATION III Depth First week Second week Third week Fourth week 0—1 m 32 86 23 85 18 65 0 — 3 m 37 10 38 16 26 15 0 — 5 m 39 22 32 65 Decrease: — The above tables show that there was a pronounced decrease in the quantity of plankton during the four weeks. This was due to the decline of the phytoplankton. The maximum de- crease, 46 per cent., was found in the 0-1 meter stratum where the phytoplankton was most abundant. The hauls from greater depths showed a minimum decrease of 36 per cent. Most of the Crustacea were found below one meter and a slight increase of them partially compensated for the decrease of phytoplankton. Lake Maxinkuckee, Physical and Biological Survey 107 Horizontal distribution: — A comparison of the tables for sta- tions I and II shows that, with two exceptions, the quantity of plankton obtained at Station II was smaller than that obtained the same week and from similar depths at Station I. The differences, however, are comparatively small, which shows that the local pe- culiarities at the former had relatively little effect on the plankton. The hauls made at the five stations in the main basin of the lake, besides the two regular ones, showed that the plankton was very evenly distributed. Vertical distribution: — The plankton was confined almost wholly to the upper 12 meters. This included the thermocline which extended from 9 to 12 meters. Undoubtedly the region below this depth remained almost tenantless because of the chemi- cal condition of the water. Only Corethra larvae were found regu- larly below the thermocline. A little more than 48 per cent, of the entire quantity of plank- ton was found in the 0-1 meter layer. As might be expected, this was preeminently the region for phytoplankton. The Crustacea were represented by a few Cyclops and a considerable number of nauplii. The 0-3 meter stratum contained 68 per cent, of the en- tire quantity. Ceriodaphnia lacustris and Diaphanosoma brachyu- rum were found mainly in the 1-3 meter stratum. Diaptomus minutus and Daphnia retrocurva seemed to prefer the region be- tween 3 and 12 meters. Daphnia pulicaria was most abundant in the region of the thermocline, or between 9 and 12 meters. Cyclops and nauplii appeared more or less abundantly throughout the upper 12 meters. Only one set of observations was made at night. The quantity of plankton obtained from the 0-1 meter stratum at night was smaller than that obtained during the previous afternoon but there was a marked increase in the Crustacea. Epischura lacustris, Leptodora hyalina and adult Daphnia retrocurva were found in this stratum at night but never in the day catches. Also there was a larger number of adult Cyclops than was usually found in the daytime. I am indebted to Prof. C. Dwight Marsh for the following list of Copepoda : Cyclops leuckarti Glaus; Cyclops prasinus Fischer; Diaptomus minutus Lilljeborg; and Epischura lacustris Forbes. The following Cladocera were collected: Daphnia pulex puli- caria Forbes, Daphnia retrocurva Forbes, Ceriodaphnia lacustris Birge, Sida crystallina (0. F. Miiller), Acroperus harpx Baird, Pleuroxus procurvatus Birge, Diaphanosoma brachyurum (Lieven) 108 Lake Maxinkuckee, Physical and Biological Survey Ilyocryptus spinifer Herrick, Alona guttata Sars, and Leptodora hyalina Lilljeborg. During the summer of 1900, plankton work on the lake was con- tinued under the immediate direction of Mr. Leonard Young, along the same lines and with the same apparatus used in the previous summer. The work extended from the middle of July until the first of September. Hauls were made from four stations. Three of these (Nos. I, II, and IV) were the stations of the previous summer's work. A fourth (No. Ill) was located on a line between Nos. I and II in 40 feet of water and on the rim of the deep basin of the northern part of the lake in which No. I was located. No. Ill is separated from No. II by a ridge (10 feet of water). At these stations hauls were made from 3, 9, 15, 25, 40, and 80 feet, according to the depth of the water. Random hauls were made along the shores near the patches of bulrushes and among them, and also on the Sugarloaf. The Sugarloaf is a small area of shallow water on the northwest side of the deep basin of Station No. I. It is about 80 feet in diameter, in water with a minimum depth of 8 to 9 feet, but surrounded by much deeper water. On the surface of the mound are beds of Potamogeton, Chara, Nitella, etc. The temperature of the water at Station No. I was taken at in- tervals of 5 feet at the time of each observation, except those made during the night. The temperature of No. II in the Kettle-hole was taken occasionally for comparison. The temperature of the bottom was found to be slightly higher (l°-2°) than in the deeper basin, although it was somewhat lower the summer before. Hauls were made at various times during daylight hours, and also at night, both before and after midnight. The plankton was examined from time to time, in order to de- termine the prevailing forms composing it. The plant forms noted were: Rivularia, Lyngbya, Anaba^na, Pediastrum, Protococcus forms, (Edogonium, Spirogyra, Draparnaldia, and Raphidium. The animal forms were Daphnia, Cyclops, Diaptomus, Rotifera, Vorti- cella, and other unknown Protozoa and Crustacea. In the upper layers of the water in the open lake, the plankton consisted almost entirely of plant forms. At a depth of about 25 feet a number of entomostracans were found, — a species of Daph- nia being the most abundant. These remained at that depth until they disappeared later in the season. In the hauls made near the shore and among the rushes, the animal forms were much more numerous than in the surface water in the open lake and were present in greater abundance. The plant forms here were in Lake Maxinkuckee, Physical and Biological Survey 109 greater variety than in the open lake and were often present in much greater quantity. The latter seems to have been due to the prevailing wind at the time. In the hauls made in daylight the greater portion of the plank- ton was found in the upper 10 feet of water, with most of it in the first three feet. In the hauls made during the night the ver- tical distribution was somewhat different. There seemed to be a downward migration of the surface plankton, so that while the total quantity remained about the same, less of it was in the first 3 feet than during the daylight. During the earlier hours of day- light it resumed its former distribution. Since the greater portion of the plankton consisted of plant forms, the absence of the photo- synthetic processes may have been the cause for this downward migration. The total quantity of plankton reached its maximum the last of July and the first of August. During the last of August the quantity decreased very considerably, and the water became quite clear. During July and the first half of August the prevailing plant form was a species of Rivularia. A species of Anabsena was also in abundance. During the latter part of August a species of Lyngbya was the most abundant plant form. Until about the tenth of August a number of entomostracans were found at a depth of about 25 feet in the open lake, but at this time they dis- appeared and could not be found in either deeper or shallower water. No uniform difference in the vertical distribution and the total quantity of the plankton at the various stations in the deeper water was detected, except that at Station No. IV in 25 feet of water, the entomostracans mentioned above were not found. The entomos- tracans were not so abundant on the Sugarloaf as in water of equal depth near the shore among the bulrushes. In the shallow water, near the shore, there was often a greater quantity of plant forms and always a greater quantity of animal forms than in deeper water. The greater quantity of plant forms was due to drifting by the wind. The quantity of plankton during this summer was less than half that of the previous summer. The greater portion consisted of plants during both seasons, but the prevailing form in 1899 was Lyngbya, while in 1900 it was Rivularia. No plankton ob- servations were made in other lakes during this summer, but in doing some sounding in Bass Lake, it was noticed that there was very much more minute vegetation in Bass Lake than in Lake Max- 110 Lake Maxinkuckee, Physical and Biological Survey inkuckee. The coefficient of the net has not been determined, so that the total quantity of plankton has not been calculated. As almost the entire volume of plankton was above the thermo- cline, which is about 35 feet deep, no relation between the vertical distribution and the change in temperature was noted. THE PLANKTON SCUM OR WASSERBLUETHE In addition to the plankton studies carried on at the lake by Professor Juday in 1899, and by Mr. Young in 1900, reported on by them in the preceding pages, some attention was given to the subject by Mr. Clark and Dr. Evermann whenever opportunity af- forded. Some of their observations are here recorded. Almost every dweller in a region where lakes abound is familiar with the annual collection of green scum over the surface or parts of the surface of the lakes. This phenomenon is known the world over wherever lakes are found. It is known in Germany as "Wasserbluethe" and in parts of England as the "Flowering of the meres." About Lake Maxinkuckee it is spoken of as "the lake cleaning itself." It is, indeed, the same phenomenon as may be observed everywhere, wherever there is a stagnant pool or dead stretch of river. Time of appearance: — The plankton scum does not appear gen- eral over the lake until late summer or early autumn. The prime condition for its appearance, in addition to proper temperature and favorable environment for the rapid development of the low forms which compose it, is an unruffled water surface. It accordingly makes its first appearance in quiet sheltered bays. The following are brief notes as to dates of occurrence: September 30, 1900. Air dead calm; flecks of foam scattered over the lake, slowly drift shoreward, and are colored green. October 3. Green scum, mixed in with insect exuviaa noted near shore. October 5. No scum, though the water is full of diffused Anabsena near the Deephole. October 15. At noon, considerable green coating of water near shore in front of Arlington Hotel. October 17. Morning calm, with considerable scum; by noon nearly as dense as yet seen. November 2. Some scum on the east side and some on the surface of the deep water, but none at shore. The lake was calm, and gave an opportunity to observe the formation of the scum. The observation was made near the Deephole from a boat. The water was full of diffused algse (principally Anabasna and Lake Maxinkuckee, Physical and Biological Survey 111 Lyngbya), which 'have a lower specific gravity than water and rise slowly, at an angle, to the surface. The Lyngbya is heavier than the Anabsena, and comes up more slowly and not in such large quantities. November 3. Clear and smooth; a large amount of Anabsena and Lyngbya on top arranged in fine parallel lines on the water surface, the lines being quite near each other and running south- east and northwest. December 1. Some Anabsena and statoblasts near shore about noon. December 8. Considerable foam tinged green with Anabsena by the icehouses and in the Outlet. December 10. Some green plankton scum on cast-up foam. No more scum was seen during the winter or the next spring, until June 12, when the first plankton scum of the year was seen. In 1904, from October 17 to the end of the year when the lake was under observation, no scum was noted. In 1906, the first scum was observed July 31, and it was noted every calm day thereafter as long as the lake was under observa- tion. August 6, the scum was very abundant along the northeast shore near the Military Academy, forming a perceptible scum on the lake. August 8, abundant among rushes off the Assembly grounds. August 15, much scum, composed of Anabsena and insect exuvise in streaks on the water surface. A great scum of Ana- bsena, insect exuvise and Vallisneria blossoms in Outlet Bay. soon forming a putrescent mass. August 16, a little scum, and considerable diffused Anabsena. August 28, no scum in the morning but much diffused Anabsena in clumps rising to the surface and collecting near shore. August 31, some scum on Twin Lakes, Anabaena and Lyngbya. September 4, a good lot of scum, chiefly Anabsena, on Zechiel's pond. November 15, some green free plankton scum under the ice south of Winfield's. In 1908, the lake was visited for only a short time and but few observations could be made on the plankton. On the morning of August 22, the following organisms were observed in surface plankton: Lyngbya, most common, many empty sheaths; Rivu- laria, a few colonies; Vallisneria flowers, abundant; Anabsena flos-aqiise, a few colonies; Cyclops, a few; Moina, a few; Cypris. a few; Vorticella, a minute greenish species usually two at the 112 Lake Maxinkuckee, Physical and Biological Survey end of a slender stalk, attached to detritus ; insect larvae and larva? casts, and a few small snails. On August 31, a fisherman re- marked that the lake began "cleaning itself" four weeks ago and that there was then a much thicker scum than at present. He said neither he nor any of the residents had seen it act so ("clean it- self") so early for 15 years. He remarked that fishes bite well before and after the process of "cleaning" but not during that time. Constitution, significance, etc., of plankton scum: — The plank- ton scum of different lakes differs considerably in its elements. In all lakes it is principally vegetable, such inert animal products as exuviae of insect larvae and the statoblasts of bryozoa sometimes being included in considerable quantities. It is best collected by skimming or by simply holding the mouth of the collecting bottle below the surface of the scum and allowing it to run in. Not pre- cisely the same elements are obtained by drawing a towing net through the scum, as many of the finer elements readily sieve through, and Crustacea in the water near the scum, but not a part of the scum, are captured. In Lake Maxinkuckee the principal elements of the plankton scum are Lyngybya asstuarii, Anabsena flos-aqux, Botryococcus braunii, Coelosphserium kuetzingianum, statoblasts of Plumatella, and the staminate blossoms of Vallisneria. Occasionally Vorti- cella was associated with the Anabsena, but this was only a tempo- rary association. The most abundant element is Anabsena, flos-aquse; indeed, it is so predominant that the history of the plankton scum is essentially the history of it. The plankton scum of some of the surrounding lakes, such as the Twin Lakes north of Hibbard, and Lake-of-the-Woods northeast of Plymouth, is also Anabaena, but it is worthy of note that that of some of the neigh- boring lakes is somewhat different. The principal plankton ele- ments of Winona Lake appear to be Lyngbya sestuarii and Micro- cystis seruginosa. Chapman Lake, Kosciusko County, and Bass Lake, Knox County, have at times a scum composed of Rivularia echinulata colonies. While in one of the Twin Lakes and in Winona or Eagle Lake some of the quiet lagoons and adjacent parts of the lake are so thickly overgrown with the little duckweed, Wolffia, that this might properly be referred to as plankton scum. In some of the lakes of the upper Mississippi, the principal plank- ton scum element is Aphanizomenon flos-aquse, a species not yet found in Lake Maxinkuckee. The character of the plankton scum varies of course with the organisms composing it. And the characteristics of Anabaena and Lake Maxinkuckee, Physical and Biological Survey 113 Microcystis, and, indeed, of most blue-green algae, are such as to make it undesirable. Upon reaching the surface on hot days the scum turns white and milky, emits a rank "green-corn" odor and dies, giving all the water about it a milky tinge. Under such cir- cumstances it is quite natural that bathers would avoid it. There is, indeed, a prevalent notion that the plankton scum is irritating to the skin, producing, in mild form, about the same symptoms as those of ivy poisoning. Several people were met who claimed that they had thus been poisoned. Two boys living in Culver claimed to have so suffered, and another person reported that about 1904 or 1905, he had been badly poisoned by the water of Lake Maxin- kuckee wherever it had touched him. A doctor diagnosed his case as "old fashioned prairie itch." On another occasion, a young man, on being invited to go in bathing during the period of plankton scum, remarked that he was afraid of getting poisoned. We have never suffered nor personally seen any one affected. In many parts of the country there is a prejudice against going swimming during "dog days." This probably has some reference to plankton-scum ; for along the Maumee River at Defiance, Ohio, some boys were noted observing some scum on the water and remarking: "It's coming dog-days and we must quit going in swimming." A very heavy plankton-scum indicates an excess of vegetation in the plankton. It is a decided nuisance both on account of the prejudice against it and the uncleanly appearance it gives the shore. It could, of course, be removed by the addition of sufficient quantities of copper sulphate, but the use of this kills algse indis- criminately and should not be attempted except as a last resort. Minnows of various species (Notropis blennius, N. cayuga, Fundu- lus diaphcmus, Labidesthes sicculus, etc.) and painted turtles eat some of the plankton. Fresh water mussels, however, are the heaviest feeders on it, subsisting almost entirely upon it and con- suming considerable quantities. Their presence in the lake is de- sirable, and they can easily be propagated in great numbers. Per- haps the thick-shelled forms of Lampsilis luteola, such as those found at Lake Pokegama, Minn., could be planted in sufficient quantities to keep the excess of plankton down, and at the same time, in due season, furnish a valuable amount of button material for the markets. The study of the vertical distribution of the plankton carried on by Juday in 1899 and by Young in 1900, and reported on by them, was discontinued in the early autumn of 1900. After that time efforts were made by whatever suitable means were at hand 114 Lake Maxinkuckee, Physical and Biological Survey to obtain examples of the different microscopic forms in and about the lake. During the winter, while raking up the various weeds of the bottom through holes cut in the ice, it was observed that they were thickly populated by various organisms, and by washing them off a great amount of interesting material was obtained. On one occasion it was observed that the drippings of Chara raked up at the Weedpatch stained the snow a bright green, and an investi- gation showed this to be due to myriads of green Stentors. During the sounding of the lake in the winter it was noted that entomostraca (Cyclops) flocked up in considerable numbers to the openings cut through the ice for soundings. With the coming of spring it was observed that the ponds and pools in the region of the lake were teeming with small forms of life different from those found in the lake. The ponds were too small and shallow to permit the use of the towing-net, so the water was dipped up and the various forms strained out and preserved. From March 25 to June 28, on trips to the Deephole to take temperatures, the towing-net was usually fastened to the boat and hauled one way. Usually large catches were obtained. On some days the hauls would consist chiefly of entomostraca and the mass had the general appearance of a yellowish jelly. On other occa- sions it was almost entirely diatomaceous (Asterionella) in which case it had a peculiar bristling appearance and was hard and gritty to the touch. During the summer and early autumn of 1906, beginning about July 26, when diffused plankton began to show through the water, frequent hauls were made with the towing-net with the following results : July 26, 1 :30 p. m., faintly bright and calm ; towing in Outlet Bay, from Chadwick's pier to the ice office, Lyngbya sestuarii, common; Diaptomus, small species; casts of shells of amphipods; Botryococcus braunii. July 27, hauls at morning and again at noon, secured Lyngbya, only a few filaments ? Botryococcus braunii, a few colonies; Diapto- mus, common; Daphnia, a few. July 30, haul over the same grounds with the same results. The Inlet seemed full of suspended alga?, which was so fine it strained through the towing-net. July 31, in a haul across Outlet Bay was obtained a great mass of entomostraca ; the water was full of suspended flocculent algse ; but it escaped the net. By noon the water by the ice-house pier was full of suspended algse (Anabsena) and in dips taken with the finer net, a good many statoblasts were obtained. Plankton scum first appeared. Lake Maxinkuckee, Physical and Biological Survey 115 On August 1, a haul was taken in Lost Lake, but little was ob- tained. August 7, a haul from Chadwick's pier across to the ice office; a calm, cloudy morning after a rain; there was obtained mostly Botryococcus, some Lyngbya, and a little Daphnia. On August 21, a visit was made to Winona Lake or Eagle Lake, near Warsaw, and 2 hauls were taken. It may prove interesting to mention results for comparison with the plankton of Lake Max- inkuckee. The plankton mass was blue-green material, turning brown, and was composed of the following elements: Lyngbya testuarii, main mass, longer filaments and more abundant than at Lake Maxinkuckee; Microcystis seruginosa, abundant, taking the place of Anabsena at Lake Maxinkuckee; Gomphonema aporica, common ; rotifers, many ; naupilii, common ; Anursea cochlearis, common ; Ceratium hirundinella, many ; Cera- tium tripos, a few ; Volvox aureus, a few ; Cyclops, a few ; Daphnia, a few. August 28. Outlet Bay in the morning; material fibrous, dirty brown ; many empty sheaths of Lyngbya ; Botryococcus, Chydorus and Daphnia. Lyngbya greatly increased by noon, evident to the eye on the surface, and diffused Anabaana in clumps, rising to the surface and collecting along shore. September 5. A haul across Outlet Bay in the morning; mostly entomostraca (Daphnia), and Lyngbya. The Lyngbya still form- ing hormogonia. The long spines of the Daphnia projecting from the net gave the mass a bristly appearance. Up to November 12, the plankton hauls had been taken occa- sionally with apparently the same results. On this date the haul examined showed a marked change; Asterionella, and Tabellaria fenestrata, two species of diatoms, were abundant; Cyclops, and naupilii, Anurasa, Microcystis seruginosa, and a little Anaba^na were present. A filamentous alga not known was abundant, tak- ing the place of Lyngbya in summer ; there were also a few colonial rotifers. On November 13, a plankton haul was taken with much the same results, the material being mainly diatomaceous. In 1908, a few hauls were made ; one on August 22, which con- sisted of Vorticella, Lyngbya and a little Anabaana. On the night of August 26, a haul made in Lost Lake, consisted of many Corethra larvae, many Cyclops, Daphnia, a few water-mites, some rotifers, and a little Microcystis. The marked difference between the plankton of Lost Lake and that of Lake Maxinkuckee was significant; that of Lost Lake ap- proaches rather that of Winona Lake. Indeed, from a comparison of the plankton elements of various lakes it appears that the dif- ferences in their plankton flora and fauna are not those of isola- 116 Lake Maxinkuckee, Physical and Biological Survey tion or distance, but the suitability of the lake for certain species. Closely neighboring lakes may have a different, and far distant lakes may have a similar, plankton. Shallow lakes, which have more or less warmth and light to much of the bottom, are more heavily populated and have both more diffused plankton and plank- ton scum. A lake resembles an organism in that there must be a certain ratio of surface to volume to produce maximum results. Lake Maxinkuckee differs from the neighboring shallower lakes, such as Bass Lake, Winona Lake, etc., both in the relative quantity of its plankton and in the organisms composing it. The smaller lakes have a much greater quantity of plankton, so that the plank- ton-scum nuisance is much greater in them than at Maxinkuckee. The plankton elements are most of them easily carried about from place to place on account of their minuteness and many of them, such as Microcystis, Anabsena, Aphanizomenon, etc., are of world wide distribution. They are therefore likely to thrive in any lake where conditions are favorable. Microcystis, which, after a little practice, can be easily recognized by the naked eye, the vacuolated masses resembling minute smoke rings, is more charac- teristic of warmer, shallower lakes, and Anabsena of deeper, cooler lakes. Another point worthy of remark is that of the great abund- ance of diatoms in the plankton during early spring and late au- tumn, and their scarcity or absence during the summer. The following are notes concerning a few plankton hauls made in 1908: August 25. No wasserbluethe yet, but one small bit of minute stuff which soon disappeared ; much Lyngbya sestuarii; a few col- onies of Microcystis xruginosa; Anabsena flos-aqute, a few col- onies ; Corethra larvae, common ; some rotifers and entomostraca ; minute white round worms in some of the plankton, one in a dead insect larva ; they may be parasitic. August 31. Minute green Vorticellse clustered about a sphere of Anaba?na ; Lyngbya sestuarii, common ; Microsystis, a few colonies ; Anabsena, 2 or 8 colonies ; Botryococcus braunii; Vallis- neria flowers; statoblasts of Plumatella, several; CEdogonium, one filament; Ostracods, common; broken off Naias, small snails, and Amphipods, abundant ; a few Daphnia ; Copepods, a few, not so common as in night hauls. September 7. Lost Lake with a fine scum on top near shore, easily thrown into ripples, composed of fine blue-green grains; Microcystis seruginosa, common, forming main mass; Botryoc- occus braunii, frequent; Anabsena flos-aquse; Lyngbya sestuarii; a little Daphnia; Navicula, a few; Cypris, a few. Lake Maxinkuckee, Physical and Biological Survey 117 THE FLORA OF LAKE MAXINKUCKEE AND VICINITY INTRODUCTION In the beginning of the investigations it was intended to limit the botanical studies to the aquatic species of plants and those in- habiting the marsh ground immediately about the lake. It was thought that no attention should be given to the purely terrestrial species. But as the work progressed the difficulty of drawing any hard and fast lines between aquatic species and land species became increasingly difficult. And the segregation of the species which bear a relation to the life of the lake as distinguished from those which bear no such relation, became quite difficult, if not indeed, impossible. Species of herbs, shrubs and trees, which at first thought would not be considered as, by any possibility, exerting any influence on the fishes or other animals of the lake, were found upon investigation really to sustain very important relations to the lake and its inhabitants. This compelled us to make our studies more and more inclusive until finally it became evident that all species of phanerogams should be included. This we have done. We have not only listed all the species determined as belonging to Lake Maxinkuckee and its catchment basin, but we have embodied in the report many of our observations regarding the abundance, distribution, and habits of the various species. In order to emphasize the importance of the strictly aquatic species it was thought best to treat them in a separate chapter, and in a special way. This we have done even at the risk of some repetition. The relation of the plants of the land to the lake, in the matter of the trees furnishing a mass of leaves to the lake bottom, pre- venting erosion, etc., has already been referred to. In addition to this there are intimate relations of the land flora to the soil and topography which make a consideration of them necessary to a com- plete understanding of the lake. During the survey of the lake an attempt was made to obtain a complete series of herbarium specimens of the various species of plants growing therein, and the work thus started, it was the most natural thing in the world to collect also along the shore and farther back from the water's edge. Many hundred specimens representing most of the species were collected and deposited in the United States National Herbarium. Collections in the country around the lake were made when other work permitted, but all seasons of the year were not as fully 118 Lake Maxinkuckee, Physical and Biological Survey represented as might be desired. Some forms were doubtless over- looked, but from time to time, additional species were added to the list on subsequent visits. Listing all the species will serve a mani- fold purpose : 1. The list will assist materially in helping one to realize the great varieties of soil and surface, and will form a valuable supple- ment to the soil survey. For example, the mere mention of the pitcher-plant will suggest one sort of surroundings, and the men- tion of the Indian-pipe, another. 2. During the time that has elapsed since the beginning of the survey, numerous changes have taken place ; some species have dis- appeared or become scarce, and new forms have come in from time to time. In the brief infrequent visits and pressure of other work while at the lake, doubtless a number of the changes have been overlooked, but such as have been observed have been recorded. 3. As much time as opportunity allowed has been given to the habits of plants, the time of their leafing, flowering, ripening, dying and other features. This is an important and generally neglected subject and it is unfortunate that more time could not have been devoted to it. It is believed that extended studies along these lines would lead to important results. Some of the widely diverging habits of closely related species such as the fact that the whole process of flowering, fruiting, ripening and germination of seed in the silver maple requires but a few weeks while in the hard maple it requires the good part of a year, and the fact that some of the sassafras trees of a neighborhood will blossom a week or more later than others, making cross fertilization impossible and the origin of a new breed possible, are only examples of suggestions that may be brought to mind by such observations. In the discussion of the various species an attempt has generally been made to give a familiar study of each species as seen in many places and under various circumstances and conditions. The latent possibilities of many of our species of plants, their wide diversity of form and feature under different conditions, and the possibility of discover- ing or developing variations that might prove valuable for use or ornament, have hardly begun to be realized. A careful study of many of our common plants, especially where seedlings come in great abundance, as in the case of silver maples, elms, and syca- mores, will occasionally discover interesting and curious mutants which are worth our careful study and contemplation. And, most important of all in this connection, is the consideration of various land herbs, shrubs and trees in their many relations as factors in determining the physical and biological characteristics of the lake. Lake Maxinkuckee, Physical and Biological Survey 119 THE AQUATIC FLORA INTRODUCTION The entire animal life of any lake is dependent for its sustenance ultimately upon the plant life of the same lake. The complete de- struction of the plant life would inevitably result sooner or later in the total disappearance of all animal life. This general statement includes, of course, the microscopic as well as the macroscopic flora and fauna, the diatoms, desmids and all minute forms of plant life, and all entomostraca and other minute forms of animal life, as well as all those larger, more conspicuous forms of animal and plant life which are evident even to the most casual observer. Without the plants the lake would be uninhabitable and zoolog- ically, an uninhabited desert. The plants of the lake are as im- portant to its animals as are the grasses of the plains to the cattle that range over them. The importance of the microscopic flora is discussed elsewhere in this report in connection with the subject of plankton; we may therefore omit from detailed consideration at this time the subject of infant fishes and their food, and pass directly to a discussion of the more conspicuous plant life of the lake and the more evident phenomena connected with its relation to the lake's fauna. USES OF THE AQUATIC FLORA As oxygenators: — The plants of a lake perform an important function in furnishing a supply of oxygen to the water. The im- portance of this function in any lake depends upon its area as com- pared with its depth; in other words, upon the ratio between the surface area where oxygen can be absorbed, and the volume of water to be oxygenated. In a lake with large area and little depth, and winds sufficient in strength and frequency to keep the surface well disturbed, the need of oxygenation by plants is less imperative. Lake Maxinkuckee, with its considerable areas of deep water and infrequency of summer storms, needs the assistance of aquatic plants to keep up the supply of oxygen. Their presence, provided there are enough fishes and other animals to use up the oxygen, makes the lake a large balanced aquarium. Some idea of the activity of the plants in supplying oxygen to the water may be obtained by visiting and observing large, dense patches of certain water-weeds in clear shallow water on any bright day. On a bright day in autumn it was observed that the con- stant breaking of minute bubbles above dense patches of Philotria 120 Lake Maxinkuckee, Physical and Biological Survey actually gave rise to a musical tinkle, and the water might almost be said to sing and sparkle like champagne. Closely associated with supplying oxygen to the water are two or three other functions of considerable importance. The first of these is the softening effect which the plants have upon the water. Certain plants, such as the Charas and the Potamogetons, abstract considerable quantities of lime from the water. These plants be- come thickly covered with a coating of carbonate of lime from which in turn they receive some of their oxygen by reducing the calcium carbonate. These and other plants also modify the bot- tom of the lake by the deposition of the lime as marl and also by the deposition of vegetable debris to form black muck. As shade: — Some of the plants, such as the water-lilies with their broad sheltering pads, furnish grateful shade to fishes and other animals of the lake. Any one who has ever rowed silently along the edge of a patch of spatterdock on a bright summer day and seen bass and sunfish and other animals resting in the shade of the broad leaves, can not doubt this value of the plants. As protection: — The larger aquatic plants offer protection to the fishes in various ways. They protect the fishes from each other. The young of many species habitually dwell among the vegetation until they have attained size and strength to compete with their larger kin ; and even fishes of considerable size find a dense patch of hornwort or Potamogeton quite helpful when pressed by larger fish. The plants also afford, protection to the fishes from the watchful eye of kingfishers, herons, fishhawks, and other fish- eating birds. Moreover, many an angler has lost many a good fish because his hook became fouled in the weeds, to the mutual advan- tage of both fish and angler, in that the fish escaped and the angler was given the opportunity to report that "the largest one got away". As food: — Many of the plants furnish food to the fishes, either directly or indirectly. So much attention has been given in recent years to plankton and its importance in the menu of young fishes and of the adults of some species such as the shad, white-fish, and shovel-nosed sturgeon, that we are likely to overlook the larger forms of plant life when considering the food of fishes. As a matter of fact, during a large part of the year many of the fishes of the lake obtain a considerable portion of their food from the more conspicuous plants. With the exception of the skipjack, few of the small fishes, after they have passed infancy, feed upon entomostraca. The vegetarian minnows feed upon plants or plant Lake Maxinkuckee, Physical and Biological Survey 121 fragments of appreciable size, and the carnivorous forms feed largely on aquatic insects or their larvse which in turn feed on the plants. The bluegill, which is largely a vegetarian, feeds directly at times upon the leaves of pond-weeds (Potamogeton), and at other times upon the little crustacean, Asellus, which feeds upon the weeds. Another small crustacean which furnishes consider- able food to fishes is the beach-flea, which feeds upon the larger plants and is usually found associated with the hornwort, Cera- tophyllum. The coarser growths of the lake are used directly by some fishes and they furnish food or lurking places to a multitude of small animals — mollusks, insects, insect larva?, crustaceans, etc., upon which the fishes feed. And again, the value of aquatic plants as food for water-fowl must not be forgotten. The quality and quantity of vegetation in the lake is of prime importance to the great flocks of ducks and coots which visit the lake every fall. These birds first feed upon the rich tender stolons of the wild celery, then upon the tender bases of the leaves. When the wild celery has become scarce they then begin feeding upon the more suitable parts of other plants such as the various species of Potamogeton, and even Philotria, Naias, Ceratophyllum, Myriophyllum, and various species of Chara ; so that, in the season, the total amount of vegetable food which the ducks, coots and other water-fowl eat at this lake is very great, indeed. It can safely be said that the abundance in the fall of water-fowl at this and similar lakes, and the period of time during which they will tarry, are largely de- termined by the character and abundance of the aquatic vegetation. General considerations: — A peculiarity of the lake flora is that there are very few annual plants, using that term in the sense of a plant that springs from seed, then flowers, fruits, and dies down in a single year. They are, indeed, generally like annuals in tex- ture, herbaceous and weak, but with little wood. We are dealing with plants growing in a region where it never freezes, and where there is never any drouth. From this point of view the region down in the water where the plants thrive may aptly be likened to a continually moist portion of the tropics. According to the commonly accepted philosophy of biology, seed-production among plants is a device for tiding the plant over unfavorable conditions much the same as the protozoa going into a resting stage or encysting. Regarded in this light, flowering and seed-production are unnecessary among the submerged aquatics, and persist mainly as an inherited habit. Considered from this point of view, one of the most curious phenomena is the efforts made by Philotria and wild celery (Vallisneria) to become fertil- 122 Lake Maxinkuckee, Physical and Biological Survey ized and set seed, the pistillate flower extending on a long peduncle to the surface of the water and the staminate blossom breaking off and floating away. Moreover, where conditions are so favorable for vegetative propagation one might naturally expect this to be a common mode. And so it proves to be; nearly all the aquatics propagate freely by means of special buds or tubers. Some of them, especially those of Potamogeton pectinatus, are of a remark- able character. The peculiarities of the various species in regard to reproduc- tion, method of dissemination, and distribution, will be taken up under each species. A few general remarks may be made here, however, concerning the behavior of the aquatic flora as a whole. In addition to bearing seeds, most of the aquatics propagate by means of so-called winter buds, which are merely fragments or bits of branches sometimes more or less modified. The expression "winter-bud" is hardly a happy one, as it serves to keep in mind the notion that the aquatic plants need some special device for sur- viving unfavorable seasons, and in that it increases the difficulty, already great enough, of divesting our minds of the notion of severe changes of season to which we are accustomed and for which the land plants must provide, but which do not apply to the aquatics. The propagation buds may be formed at almost any time of the year during the growing season, many of them during August. Every one is acquainted with the facility with which many of our herbaceous plants, such as the geranium, purslane, wild morning glory, etc., send out roots from cuttings, and how the presence of water or moisture favors the formation of such roots, so that the usual way to start some plants, such as the willow, oleander, etc., is simply to place the end of a cutting in a vase or bottle of water. Among the aquatics we have the herbaceous growth and the water always present. A cause contributing to the formation and de- tachment of "winter-buds" during the autumn months is that there is then considerable wind and choppy weather so that the plants are subjected to unusual stress and strain, and portions are easily detached. The portions detached drift about hither and yon with the various movements of the water. They rest during the period when the lake is covered with ice, but are further disseminated and scattered by the gales of early spring after the ice has melted. As a result of the more or less permanent nature of the plants and plant-patches in the lake, and of the habit of detached portions rooting and growing wherever they settle or the shifting currents carry them, the locations of the old plant-patches do not change much, but new patches spring up here and there. Such influences Lake Maxinkuckee, Physical and Biological Survey 1£3 as the removal of protecting trees, opening the lake more to the sweep of winds, conduce to the dissemination of the under-water plants. It is perhaps due to this, and perhaps to other less evident causes, that the lake has become markedly more weedy than it was at the beginning of our study. To cite a specific example, the shallow water just off the north shore of Long Point, which was once over comparatively barren sand, now supports a dense and luxuriant growth of weeds, especially Philotria. It is quite pos- sible that another very active contributing cause is to be found in the increasing scarcity of waterfowl. Formerly, immense flocks of coots and ducks made great raids on some of the water-plants,— first on Vallisneria, and then, when that was gone, upon Chara and other weeds. The birds uprooted the plants before they ripened or set seed, so that the long, heavily seeded fruits of Vallisneria, once almost a curiosity in the lake, are now abundant, due, in part at least, to the greater scarcity of water-fowl. Not only did the ducks uproot the plants, but they also ate as a choice delicacy the tender stolons upon which the plant relied for vegetative propaga- tion, and in the early winter, after the ducks had finished their raids, little or none of the Vallisneria was to be found. So conspicuous and apparent is the increased weediness of the lake that a local report has gained circulation that the "Fish Com- mission has planted the lake full of weeds for fish-food, and that as a result the fish are so well fed that they will not bite, much to the detriment of good fishing" ! As compared with other lakes of the state, Lake Maxinkuckee is not so weedy as some of the shallower lakes which warm well to the bottom and have all their bottom area at such depths that plants can thrive, but it appears to become more weedy year by year. It is somewhat more weedy than lakes with a smaller area of shallow water, such as Tippecanoe Lake. Its condition as regards quantity of vegetation is well expressed by Dr. Scovell who, in discussing the origin of the marl says : "Out to a depth of 25 feet the lake abounds in vegetation. Over hundreds of acres the vege- tation is as rank as in a field of heavy clover, the vegetation con- sisting largely of different species of Chara and Potamogeton, with Vallisneria, Philotria, Ceratophyllum, Naias and Myriophyllum in abundance." The comparison with a field of clover suggests at once the im- portance of the vegetation as soil builders of the bottom, but in this respect it is to some extent misleading, inasmuch as in the case of the Chara and the other plants in deeper water, the dense patches seen year after year are the same, not decaying and being annually 124 Lake Maxinkuckee, Physical and Biological Survey renewed as in the case of the clover, but the same individual plants persisting year after year. In the shallower water, indeed, many of the plants, such as Vallisneria, do die down, or their leaves are pulled off by ducks and washed up on the shore in great rolls. The rolls of plants which wash ashore decay into a rich black soil to be again washed down into the depths of the lake by the undertow. In shallow lakes, where warmth and sunlight can reach the bottom, doubtless one of the most important influences in oblitering the lakes is the im- mense mass of vegetation which grows up and dies down yearly. The importance or efficiency of water plants in filling shallow lakes and shallow parts of lakes is well shown in the southeast part of the lake along Norris Inlet, and along the Outlet where what was once lake bottom has been built up into flat sedgy marshes (Green's marsh and Norris Inlet marsh), the lake al- ready having lost from this cause an area of over 70 acres, along with its continuity with Lost Lake. THE LAND FLORA INTRODUCTION A striking character of some of the small ponds and kettle-holes about the lake is the sharp division of the vegetation into concentric zones, so that the ecological aspect of botany is abnormally intensi- fied. This is the case at Hawk's marsh and at some of the wood- land ponds in Farrar's and Walley's woods. With Lake Maxin- kuckee, which is, of course, only a pond on a larger scale, the same condition might be expected to obtain, but generally speaking, it is not the case, because the steep shores come close to the water's edge, making the transition from the high land flora to the lake flora quite abrupt. It is manifest, however, in such regions as Norris Inlet and Green's marsh which were once parts of the lake. It is much more manifest about Lost Lake than in Lake Maxin- kuckee, and formerly, when the marsh about Lost Lake was more flooded than at present, and covered with shallow water species of Chara and Utricularia, it was more marked than at present. Of course, there are numerous forms, such as the bulrushes, pickerel-weeds, mud plantain and others, which belong equally upon the land or in the water, and in other cases there are dimorphic species having one form adapted to the water and another to the land, so that it is difficult to tell just where the lake forms end and land forms begin. But generally speaking, the lake and land floras are pretty markedly distinct. Lake Maxinkuckee, Physical and Biological Survey 125 While the division line between the lake flora and the land flora is in most cases pretty sharply drawn, it is not so easy to tell where the boundary line lies between the plants having some influence upon the lake and those which have none, if there be any such. The forests upon the shores of the lake have a marked influence in sheltering it from strong winds. As everywhere else, their leaves break the impact of heavy rains, allowing the water to sink gradually into the soil rather than run directly into the lake car- rying their burden of soil with them. In this last mentioned func- tion, indeed, forests some distance back from the lake exercise a very important influence on the lake. It is known that the lake derives its chief supply of water from springs and flowing wells, the waters of which sink into the surface, no one knows just how far from the lake. Everybody knows how the disappearance of springs is associated with the removal of forests. Indeed, during the time that the lake has been under observation there has been a marked diminution in the force and volume of many of the flow- ing wells, and some of the marshes, such as Green's marsh and the Inlet marsh, which at the beginning of the investigations were miry, quaking bogs, where one could walk only on tussocks, are now comparatively solid ground and are, indeed, mown meadows. This change is a consequence of the lowered water-table of the whole general region, and has taken place in other parts of the state to such an extent that where cattle once would mire there are now fields of corn and alfalfa. The falling leaves from trees near the lake sink to the bottom of the lake and may be dredged up at all depths. Their decay forms a black mud, and, although on account of the large area of the lake, they are not so great a factor as in some of the smaller lakes, their amount and influence is considerable. In one feature they are quite important. It is between the leaves, as they sink to the bottom, that some of the plankton algse, especially Anabaena, the most abundant, and when in excessive abundance, the most of- fensive of all the plankton-scum plants, hibernate during the win- ter. Even the humble grassy covering of the sand-hills about the lake has a direct bearing upon the latter; for when these are de- nuded of all vegetation, the sand drifts and blows ; during the year a considerable quantity is blown into the lake. During the winter, when there is no protecting snow, the ice is soon covered with a film of sand. Even the meadows about the lake, with their grasses and other plants, bear a relation to the lake, in that they furnish a habitat for various insects, particularly grasshoppers, which in one way or another enter into the menu of the fishes. As shown else- 126 Lake Maxinkuckee, Physical and Biological Survey where in this report, the quantity of grasshoppers caught in the vicinity of the lake and used as Jbait by the anglers is astonish- ingly large. Moreover, various trees and shrubs leaning over the lake are the homes of various insects which frequently drop into the lake. In the spring of 1901 it was observed that the water-surface was covered with vast numbers of leaf -eating beetles. It was later discovered that these laid their eggs on the leaves of the willow trees along shore and that the black larvae which hatched, defoliated the willows. Moreover, the myriads of midges, may-flies and caddis-flies which spend the larval period of their lives in the water and furnish an important part of the food of the fishes, when they emerge from the water and take their nuptial flight, run a gauntlet while in the air, and are reduced to a re- markable degree by the forest-dwelling birds along shore — cuckoos, warblers, song sparrows, night hawks, etc. The number of forest and weed seeds that blow into the lake and float upon its surface is very great. The sycamore seeds blow out on the ice in great numbers and are washed ashore in spring. Some conception of the immense amount of seeds borne on the surface of the lake can be obtained by a walk along the beach almost any season of the year. In places there are long rows of seedling sycamores, in others, seedling elm and willow. In the autumn of 1913 whole stretches of beach were covered by an almost continuous mat of little seedlings of Erigeron. These seeds, it is true, probably never have any important influence on the lake, prob- ably none of the lake-dwelling animals feeds upon them; but they form at times a noteworthy part of the plankton towings, and in- crease greatly the number of forms the plankton-student has to puzzle over. If not a part of the actual plankton, as generally un- derstood, they certainly constitute at times a considerable part of the plankton catch. There is another consideration which makes the land flora worthy of our attention in an attempt to study the lake. Lake Maxinkuckee was taken at first as a typical glacial lake ; but careful study proves it not to be such ; at any rate, a large number of small Indiana lakes are pretty markedly different from it and have a closer set of resemblances among themselves than it has to any of them. It is a lake of marked individuality, and this individuality is indissolubly associated with its surroundngs — the sorts of soil and accompanying plants and animals. A given association of plants will at once suggest to the botanist the type of soil, slope, etc., and soil surveys to be complete, should always be associated with botanical surveys. Lake Maxinkuckee, Physical and Biological Survey 127 The botanical study here given can therefore be regarded as complementary to the soil survey of the region. The Miami sand, which extends from Culver Academy grounds to Murray's, reach- ing west beyond Culver to the large muck areas, exhibits, in the main, a different flora from the Miami sandy loam about the south half of the lake, from Murray's around to Aubeenaubee Creek, and this again is different from the rich woodlands of the Miami gravelly sandy loam extending from Aubeenaubee Creek to Culver Academy grounds. The small intercalated areas of muck along the Inlet and Outlet, and other soil areas, are also associated with more or less peculiar floras, so that on the whole the area about the lake is a veritable botanist's paradise. Attention is called to the fact that the botanical work about the lake was done at a time when other duties occupied attention, and, indeed, was done only when studies of the lake permitted momentary interruption. While it is believed practically all the phanerogams of the lake are represented in the list, the same thing can not be said of the land plants, and there is doubtless a consider- able number of gaps yet to be filled to make the list complete, a number of species of the land plants having escaped observation on account of the pressure of more insistent duties. During only one year, 1900-1901, was the work carried on without considerable interruptions. From time to time since then, on short visits to the lake, attention has been paid to the flora as opportunity permitted. Although the botanical studies of the lake have been only in- termittent and fitful, they have extended through a considerable series of years and have attracted attention to a phase of botanical study which has not been generally appreciated, namely, the histori- cal phase. Of recent years the cataloging of the plants of limited areas has begun to be looked upon as the lowest form of botanical ac- tivity, so thoroughly despised, indeed, in some quarters, that it is not considered sufficiently worth while to engage the attention of first-year high-school pupils, and as a corollary to the contempt with which the "mere systematist" has fallen, the good old habit of "botanizing" and making herbariums and getting acquainted with local floras has given way in many places to comfortable indoor studies, and the study of botany has become a "sedentary occu- pation." A complete list of the plants of a given area, however, made as a basis for the study of changes of flora in the progress of the years, keeping record of forests removed, of wholesale marsh floras exterminated by drainage and tillage, and of the date of disappearance of original forms and the entrance of new, would 128 Lake Maxinkuckee, Physical and Biological Survey be of inestimable value and interest. It was during the period in which the lake was under observation that several species, such as the tamarack, pitcher-plant, yellow-fringed orchis, and a few others wholly disappeared in places where they were once abundant, and appear on the way to complete extermination in this region. It was only a few years before the investigations began that the yel- low and white sweet clovers made their appearance in the region. The entire-leaved prickly lettuce had just appeared and was repre- sented only by a few pioneers ; the typical form with incised leaves had not yet appeared. A few adventurers, like the first colonists of the new world, attempted and failed. About 1906, the Russian thistle first made its appearance in the form of a small patch along the Assembly grounds, but this did not persist. It was the same year that the tumbleweed or winged tumbleweed, Cycloloma, made its appearance at the lake, although it had been seen several miles west of the lake in 1904. It was only in the year 1909 that the dainty Galinsoga, whose advent had been looked for for some time, and a red-leaved Oxalis, perhaps O. rufa, first made their appear- ance in the railroad grounds, in all probability from seed in soil brought directly from Sewickley, Pa., the location of the Pennsyl- vania Railroad's propagating gardens. GENERAL FLORAL REGIONS As has been said, the general floral regions correspond pretty closely with the soil regions. The following general areas are rec- ognized in this report : (1) the beach, (2) the lake plains, corres- ponding to the muck of the soil survey and most marked at Inlet marsh and the marsh about Lost Lake, (3) low woodland, (4) high gravelly sandy woodland as at Long Point, (5) upland clay wood- land, as Overmyer's field, and, back of the Inlet marsh around beyond Van Schoiack's on the east side, (6) upland sandy wood- land, as the stretch of forest north of Lost Lake marsh, (7) upland loamy woodland, as Culver's woods and northeast of the lake, (8) gullies or creek bottoms such as those along Culver's and Over- myer's creeks, (9) woodland ponds, (10) sphagnous bogs, and (11) shifting sand regions. The beach flora: — The wide beach on the east side is compara- tively barren, its barrenness being due to its sandy soil, which is easily moved about by waves. From Culver Academy grounds on around to Norris Inlet there is on the narrow, sandy, gravelly beach a pretty well marked flora, the elements .of which are cockle- Lake Maxinkuckee, Physical and Biological Survey 129 burs (Xanthium), Cyperus diandrus, Verbesina alba, peppermint, spearmint, spotted touch-me-not, barnyard grass, germander, water hoarhound, all pretty well distributed, with the cockle-bur, touch- me-not, Verbesina and Cyperus most abundant at Long Point, the Teucrium and water-hoarhound most abundant north of Winfield's. There are long patches of bulrushes and chairmakers rushes, the location of which is given in detail under those species, a few patches of arrow-head and pickerel-weed, also described elsewhere, garden parsnip in front of Green's, barnyard grass, and Cicuta bulbifera, the bulb-bearing water hemlock, along the southern shore of the lake. There was a small clump of sand-bar willows at Long Point, but these have disappeared, and below Farrar's low Cornus and Cephalanthus leaned over the shore in places. Where springs entered the lake and flowed over the sandy shore, as at Lakeview Hotel, a species of Chara grows on shore, making a beach plant, and at the entrance of a few creeks watercress grows luxuriantly at the water's edge. In addition to these there is at various times a temporary flora of seedlings of all sorts of winged- seeded plants such as willow, sycamore, elm, Erigeron, etc., but these always soon disappeared. Behind the beach in certain places where there is no steep shore, such as along the low woodland at Overmyer's and from there to beyond the Norris Inlet marsh and again in front of a small pond on the southeastern shore of the lake, there is a well-defined ice- ridge. Although this is a well-defined area, differing markedly from the land on either side, especially as regards drainage, it can not on the whole be said to have a distinct flora. The only plum tree close to the lake grows on the ice-ridge, and the only patch of running strawberry bush, Euonymus obovatus, about the lake region was found on the ice-beach in front of Overmyer's low woods. The Lake Plains: — These are represented by the Inlet marsh and Lost Lake marsh, the latter including Green's marsh. The soil is mucky, and mucky areas along Aubeenaubee Creek and the Outlet below Lost Lake much of the way down to the Tippecanoe River are of this character as regards both soil and flora. They are flat level plains, densely overgrown with various sedges, chiefly Car ex stricta and C. lanuginosa, along with the tall marsh shield- fern, Dryopteris thelypteris. In the Inlet marsh there are plenty of cattails, considerable swamp loosestrife, and scattered Comarum palustre. Green's marsh contains various low shrubs principally Bebb's willow, red-osier dogwood, and button-bush. There was 9— 17618— Vol. 2 130 Lake Maxinkuckee, Physical and Biological Survey originally a level flat area much like a lake-plain across the road at the mouth of Culver Creek which was densely overgrown with the chair-maker's rush (S. americanus) but these have disappeared and the area is now a flat meadow. Low woodlands are represented only by a small area at the mouth of Overmyer's Creek, and the most prominent characteristic of this is the abundance of swamp ash. The upland clay woodland is modified in many places by clearing and cultivation, a characteristic of it being the presence of the shellbark hickory which is generally replaced on more sandy areas by the small fruited hickory, Hicoria microcarpa. A clump of red- bud, Cercis canadensis, the only patch about the lake, is found in this soil back of Van Schoiack's. In other respects it is much like the other upland forest. The high gravelly sandy woodland is represented by the Long Point forest. This, being near the base of operations, was studied in some detail. The trees were rather scattered and clumpy. Within an area of 4 square rods chosen as typical there were 4 trees of Quercus velutina or black oak, 5 trees of Hicoria microcarpa or small fruited hickory, and 5 trees of white oak. The largest tree within this area was a black oak a foot in diameter, and the small- est a hickory 3-J inches in diameter. The trees averaged 6 inches in diameter. There were a few scattered sycamore and willow along shore, and large-toothed poplar, Popidus grandidentata, and occasional elms. The herbage consisted of only a few scattered spears of grass and much scattered elm-leaved goldenrod. Much of Long Point had been cleared off so that the original forest was gone. Green's woods near Lost Lake, a continuation of the same but perhaps a trifle more sandy, contains numerous patches of moss near its edges, and usually plenty of scattered toadstools and occasional Indian pipes in the rich woods mould. The almost pure sand woodland is exemplified in the forest on Long Point. This is chiefly of small black oak and contains very little or no herbage. The accumulated leaf fall of years has not decayed, but the crisp, dry leaves even in mid-summer lie as thick and rustling as they do in most woodlands in autumn, and in the exceeding dryness of the forest floor it reminds one of the dry pine- needles that carpet a pine forest. The upland loamy woodland, exemplified by Culver's wood, con- sists of an exceedingly rich black sandy loam surface soil with a magnificent forest of immense tulip-trees, sugar, black and white walnut, beech, coffee-nut, bitter-nut, red oak, elm, white oak, chest- Lake Maxinkuckee, Physical and Biological Survey 131 nut oak or sweet oak (Q. muhlenbergii) , with immense fruitful groves of papaw, scattered spice brush, and for herbage all the common plants that grow in rich woods mould, — hepaticas, anem- ones, pepper-and-salt, in that great variety which delights the flower lover and botanist. Some notion of the variety produced in this region may be obtained from the remark, probably not exag- gerated, of a man who was hauling wood from this region and who said he had 27 species of wood in one cord. The gullies have a rich, springy soil usually black and in places more or less miry. On their sides grow luxuriant but tender moisture-loving ferns, while in the bottoms flourish patches of skunk cabbage, large flowered asters of various sorts, lizard's-tail and the like. Farrar's woods, Walley's woods and Zechiel's woods along the south and southwest shores of the lake are mostly rather flat, sandy but moist woods, in general without salient characters enough to be characterized briefly except that all contain woodland ponds, and the two latter are characterized by having plentiful low heaths such as Gaylussacia baccata, checkerberry, false beech-drops, etc., scat- tered through them. Holton's woods near Walley's contain the only clump of river birch in the region, and Walley's woods the only clump of Princess pine, Chimaphila umbellata. The ivoodland ponds are so various that it would prove weari- some to describe them in detail. Those of Farrar's woods are shal- low, the bottoms thickly covered with leaves, the water, which is present only during the wet season of the year, is usually of a tea color. The plants are few. A few trees of the various-leaved cot- tonwood, Populus heterophylla, Cephalanthus bushes, their bases skirted with mosses and liverworts, a few herbaceous species re- markable for their adaptability and variability of form, the water- parsnip, yellow water-crowfoot and the curious Riccia hdescens which floats about on the surface like green butterflies and repro- duces by a division into almost exactly equal parts. All these herbaceous plants flourish, but assume entirely different forms dur- ing the dry season. For their fauna they have numerous frogs, speckled and Blanding's tortoises, both almost entirely absent from the lake, the slender-pincered crawfish Cambarus blandingi acutus, not found in the lake, and a remarkable Sphserium which spends half its life, the dry season, among the moist leaves in a state ap- proaching suspended animation. They, along with other shallow pools, contain the fairy shrimp and doubtless various Entomostraca of unusual habits and characters. Farther down toward Walley's 132 Lake Maxinkuckee, Physical and Biological Survey woods the woodland marshes are different, usually containing quak- ing aspen about the margin along with winterberry or black alder and choke-berry with Sphagnum in the center. One of the circular woodland ponds studied more in detail consisted of 4 distinct zones of vegetation, the outer border being the usual high-ground forest, then a ring of willows and Rosa Carolina, then a ring of sedges, boneset, smartweed and Erechtites, and in the center a circle of rice cut-grass. Swamp white oak was common in this pond. The peat bogs, once extensive west of the lake, have most of them been greatly changed if not destroyed by drainage, and their curious faunas exterminated. Most of them contained the tama- rack as their principal or only tree. Hawk's marsh, on the south- west corner of Culver, fortunately remains, and it is to be hoped will long continue in its present state. It is surrounded by an al- most impenetrable tangle of various low bushes, principally moun- tain holly, black alder, tall bush huckleberry and poison sumac. Inside this tangle is a deep, spongy bed of Sphagnum, the outer border thickly overgrown with tall, erect ferns (Anchistea) and farther inward evergreen heaths, leather-leaf, marsh-rosemary, etc., with a sprinkling of pitcher-plants and cotton-grass. Various orchids, such as the yellow-fringed orchis, are common. At the inner edge of the Sphagnum are masses of cranberry vines and spatulate-leaved sundew, while innermost of all is a pond full of spatterdock and Utricularia. The shifting sand regions are composed of a somewhat heavier sand than dune sand and are areas once covered with a growth of forest, chiefly low scrub oak (Q. velutina) . These sand-hills do not drift in a mass as do the genuine dunes, but the winds gutter out the sand in places leaving angular rock fragments. The blown sand drifts fence corners and forests full and gradually buries them. The flora is generally a scattered growth of Cyperus filmiculmis. Some cacti, said to have escaped from a neighboring cemetery where they are said to have been planted, are slowly occupying these hills. Patches or peculiarities of distribution of individual species, such as the long line of sour gum (Nyssa sylvatica) along the edge of Green's woods and the east bank of the outlet in Walley's woods, clumps of witch hazel back of Green's and on the east side of the lake, are best treated in discussing the different species. In the following discussion of species the various plants are de- scribed as seen in varied places and times, representing the species in as many lights as possible. Lake Maxinkuckee, Physical and Biological Survey 133 COMPARISON OF AQUATIC AND LAND FLORAS Perhaps the most striking difference between the flora of a land and of a water area is that the land flora lies open to the eye while much of the flora of a lake, especially of a deep lake, is hidden from view. It is easy to form a fairly complete mental picture of a landscape with which we are familiar, but in the case of a flora at the bottom of a lake the situation is entirely different. In the case of permanence or persistence of individuals, there are curious differences. On the land, there are herbs, shrubs and trees — an- nuals, biennials and perennials — the trees conspicuous landmarks enduring year after year, the herbs many of them dying entirely down with the course of a year. On the other hand, the aquatic flora is almost entirely herbaceous; the only analogue we have -to trees being the water-lilies and spatterdocks, the thick horizontal rootstocks of which would, if standing erect, make respectable saplings. But while the plants under water are all herbaceous and relatively frail, the phenomenon of annual growths which live but to produce seed, and perish when that is done, does not obtain among the aquatic plants. The only case that comes to mind is that of some of the delicate Charas and Nitellas, and the slender Naias which grows at the water's edge, and the deeper growing plants of Naias. In a certain sense, at least so far as plant life is concerned, the region under water may be described as sub-tropical. The most important difference between the temperate zone and the tropics is, not only in a greater amount of heat in the tropics, but also in the more equable distribution of the heat throughout the year, and the absence of a freezing temperature at any time ; and this is just what we have in the waters of the lake everywhere below the freezing surface. The temperature of the air about the lake has a range of about 125° F., frequently going considerable below freezing, while the water under the freezing layer at the sur- face has a range of only about 55°, or not half as much as that of the air, and is always exempt from a freezing temperature. In the region immediately about the lake the lover of beautiful grounds may wish in vain for the "broad-leaved evergreens", the holly, the ivy and the rhododendron, but just a little way beneath the ice the broad green delicate leaves of the pond-weeds retain throughout the coldest winters almost the freshness of summer days. Moreover, in the methods of perpetuating their kind, the aquatic plants differ considerably from the land plants in that there is hardly a single species which does not have some effective method 134 Lake Maxinkuckee, Physical and Biological Survey of vegetative propagation, either by special propagating buds or by the rooting of broken-off portions. In only a few are seeds formed in great abundance ; in many, seeds are formed scarcely or never at all. In the botanies concerning land plants, there is much about eco- logical groups, plant societies, halophytes, xerophytes, mesophytes and the like, and one of the most striking features dwelt upon is the association of plants in related groups as regards soil, mois- ture, slope, and the like ; but in the lake bottom no such differences obtain; the only difference in the amount of moisture is in its depth, and the drainage is the same everywhere; the only differ- ences affecting distribution of the plants being those of the depth of water, the nature of the bottom and the question of previous occu- pancy by some other species. Plant patches in the lake: — The positions of the plant patches of the lake are fairly constant, inasmuch as most of the plants are perennial or grow from perennial rootstocks. New patches may of course spring up in various places. The most conspicuous plant patches are those of aquatics with aerial or emersed leaves and of these the ones most likely to be remarked are the white and yellow pond-lilies, Castalia odorata and Nymphsea advena. These species, though abundant in Lost Lake, are rare in Lake Maxinkuckee, as there is not enough of the deep soft black mud in which they thrive best. There is a small patch of both species at the beginning of the Outlet, and considerable of the Nymphsea but only a little of the Castalia, in the Norris Inlet region. Next to the water lilies, the most conspicuous patch-forming plant is the large-leaved pondweed, Potamogeton amplifolius. This plant is abundant at the Weedpatch, and forms large noteworthy patches near Norris Inlet, southwest of the Kettlehole, east of the Gravelpit, east of Arlington Hotel, and in scattered localities through Outlet Bay. Along with other pondweeds whose leaves come in masses near the surface, the resistance which the foliage of this plant offers to water in motion has a marked calming effect on small waves, and at times when most of the lake surface is well- rippled the Potamogeton patches are marked by areas of calm. Potamogeton natans, like P. amplifolius, forms pretty well- marked and conspicuous patches. These are all rather close to shore, consist of only a few plants, and occur most frequently in the Norris Inlet region. With the exception of the species of Chara, some of which grow over large areas, and shore plants, such as bulrushes which will be considered later, these are about the only plants of the lake which form definite patches. The gen- Lake Maxinkuckee, Physical and Biological Survey 135 eral locality where other species grow will be taken up in discussing the various species. While considering the question of permanence and position of plant-patches in the lake it may not be out of place to refer to un- attached plants, including the floating duckweeds, and of course, the alga-masses, but more especially those anomalous forms which have no roots developed, such as Ceratophyllum and Utricularia. There is nothing among land plants which is analogous to them. The tumble-weeds suggest them somewhat, but the disassociation of the tumble-weed from its roots is for the sake of great motility and distribution of seeds, while the Ceratophyllums and Utricu- larias are loggy, hardly affected at all by currents of air and little by currents of water. They really appear to be forms of im- mensely overgrown propagating buds, and, although they produce seeds, are themselves largely propagated by vegetative reproduc- tion. In entering upon the discussion of the several species of plants which inhabit the lakes, it has been thought best to take them in the order in which they occur, first disposing of the floating forms, and then beginning with those inhabiting the deeper waters, and proceeding from thence toward the shallow water. The usual method of taking plants in the order of their supposed relationships has been avoided, chiefly because they occur in that order in the general list accompanying this report, and partly because the ques- tion of genetic relationship is not here the one primarily under con- sideration. It was thought best to begin with the center and pro- ceed centrifugally, because there is no doubt of where to begin here, while beginning at the shore would leave no definite starting point. Considering species in the order suggested, moreover, will present them in the societies in which they occur as nearly as that can be done. The floating aquatics, including the rootless phanerogams, Ceratophyllum, the various species of Utricularia, the minute float- ing duckweeds, and the unattached algal masses, such as Spirogyra, Mougeotia and the like, form a class by themselves. Ecologically, they belong in the group with the plankton. Theoretically speak- ing, these plants have no local habitation but drift hither and yon as currents and winds drive them. As a matter of fact, they are not so continually in motion as one might imagine, the algal masses often becoming tangled in the tops of the rooted plants, the loggy submerged Ceratophyllum and Utricularias responding very little to winds, and the duckweeds occupying nearly the same position year by year in the sheltered nooks. The duckweeds are always 136 Lake Maxinkuckee, Physical and Biological Survey found rather near shore, but the other plants are found throughout the lake at nearly all depths. The strictly aquatic plants living within the borders of the lake, being an essential part of the environment of the fishes and other denizens of the lake, were studied in considerable detail. During these studies one of the salient facts that impressed itself continually upon the mind was that the different plants of the lake were aquatic in different degrees. Taking the large genus of pond weeds or Potamogetons, for in- stance, we have among them a number of forms with all the leaves fitted only to under-water life, and so constituted that upon ex- posure to the air they crumple up and perish almost as soon as does a fish out of the water. One of the most pronounced species of this type is the handsome P. robbinsii, which lies nearly flat on the bottom, and has become so thoroughly and completely aquatic that it rarely or almost never even ventures a flower-spike up out of the water, but depends almost entirely upon vegetative buds for propagation. The large-leaved pondweed, Potamogeton amplifolius, on the other hand, has two well-marked kinds of leaves — thin, almost transparent submersed leaves, and thick, leathery floating leaves. It has a well-developed flower-spike which projects prominently above the surface of the water. Finally, in Potamogeton natans, we have a form in which the submersed leaves, though present, are small, undeveloped, and only temporary, the leathery floating leaves being the most prominent and functional ones. Indeed, where these plants grow near shore they are frequently stranded on mud-banks by the receding of the water, and there develop into mud-plants rather than aquatics, with stiff aerial instead of leathery floating leaves. Another case is that of the water star-grass, Heteranthera dubia. This frequently grows in several feet of water, entirely submersed, and very closely resembles some of the narrow-leaved forms of Potamogeton. In this situation it rarely flowers. Sprigs broken off by the waves and cast ashore, however, quickly strike root, bear firm aerial leaves, and produce numerous pretty yellow flowers. Again, we have one of the species of arrowhead, Sagittaria graminea, the leaves of which form a close rosette at the bottom of the water, these leaves being strictly aquatic and the whole plant, when not in flower, hardly distinguishable from a strict aquatic in all its relations, the seven-angled pipewort, Eriocaulon septangular ~e. Lake Maxinkuckee, Physical and Biological Survey 137 • Two more noteworthy instances occur to mind. At certain places along shore there is found growing in the water a plant which in leaf-form and general habit, resembles Potamogeton natans, but which is really a smartweed bearing pretty spikes of pink blossoms; and finally in the waters of the lake among the pondweeds and milfoils one finds a most remarkable plant which has whorls of dissected leaves and bears a considerable resemblance to some sort of milfoil or a close resemblance to the aquatic form, Cabomba. This plant upon blossoming and fruiting proves to be a species of bur-marigold. It will occur at once to the reader that the region along the shore-line is an excellent place to study evolutionary forces at work, and the question of the possible relations between the shore plants and the aquatics will at once arise. In the temporary woodland ponds the changes of form of plants to suit conditions is much more striking, but not so deep-seated. Here we have the remarkable water-parsnip, which in early spring when the pond is full of water, is a rosette of purple; finely-dis- sected leaves appear, but later as it shoots up, its stalk puts out leaves more and more nearly entire as it approaches the water- surface until the aerial leaves of the same plant that bore collaps- ible submersed leaves below, are firm and almost entire. A water crowfoot of the ponds changes the shape, texture, and general as- pect of its leaves so much after the water dries that it looks like an entirely different plant. And the woodland pond and the lake edge each has its own species of Riccia that have parallel changes and land forms entirely different from the floating form. A contemplation of these facts arouses speculation as to the relationship and origin of the land and water floras. Conscious- ness of the great adaptability which plants possess, and the recog- nition of a greatly modified bur-marigold and smartweed among the members of the water flora, cause us naturally to expect some genetic relationship between the plants on land and those in the lake. In this expectation we are disappointed. With the two ex- ceptions given above, the aquatic plants belong not only to strictly aquatic genera but usually also to strictly aquatic families and per- haps orders. Zoological and botanical systems are so unlike that it is impossible to make exact comparisons, but, generally speaking, the plants of the lake are about as far removed in relationship from the plants of the land as the fishes of the lake are from the animals of the land. And yet we recognize among the plants tantalizing similarities. The flowering plants of the lake evidently arose from terrestrial 138 Lake Maxinkuckee, Physical and Biological Survey • ancestors and stand in the vegetable world much where whales do in the animal kingdom. The mechanism of fertilization among the phanerogams is not at all adapted to aquatic life and generally special devices have to be arranged to bring it about, such as the breaking off and floating of the staminate flower and elongation of the flower-stalk or flower-tube of the pistillate flower as in Vallis- neria and Philotria. Few of the aquatic plants bear conspicuous flowers, the water-lilies being notable exceptions, and none bears fruit in the garden or horticultural sense of the term, that of the water-lilies again being the closest approach to it. The problem of just how the blossom of the horn wort, Ceratophyllum, is fertil- ized we have not solved; probably the plants float at the surface during the flowering season. Of the phanerogams in the lake, Naias seems to have solved the problem of under-water fertiliza- tion, although we do not know how this is accomplished. It is, therefore, the furthest removed from the land series. Two of its relatives not found in the lake, Zannichellia and Zostera, flower and fruit under water, the latter by the development of a peculiar glutinous, stringy pollen. THE ALG;£ INTRODUCTION With the exception of the Characea?, which stand rather in a group by themselves, the algne do not as a whole form a very con- spicuous part of the flora of the lake, the waters out from shore being generally pretty free from forms that would attract atten- tion. This is in keeping with the character of the lake, it having few capes or bays, relatively little shore and considerable deep water. A luxuriant algal growth is generally associated with much shore-line or shore conditions, large areas of shallow water and rich, muddy or leafy bottom. The various ponds about the lake in their proper season are richest in algal growths, some of them so much so that after they have dried in summer their place is covered by almost a single immense white sheet of paper — the bleached-out mats of algse which once covered the water surface. Lost Lake taken as a whole is richer in the coarser forms of algse than Lake Maxinkuckee. However, in the larger lake, along shal- low or sheltered stretches of shore with rich bottom, as in the neighborhood of the Inlet and Outlet regions, Aubeenaubee Bay and the artificial channel by the Medbourn ice-houses the fila- mentous forms originally grew in great abundance and very lux- uriantly, furnishing hiding places and a good deal of food for the Lake Maxinkuckee, Physical and Biological Survey 139 great number of turtles that dwelt among them. Some of the algse are to be found the year round, especially where there are springs which keep the water abnormally warm. Others as Draparnaldia (which is rare in the lake) and the diatoms thrive more in cold water and appear in the greatest abundance during the winter. The coarser filamentous algse function in the lake as the higher plants do, i. e., they help oxygenate the water and serve as food and shade for fishes. Various insect larvse and probably most of the smaller herbivorous fishes, as well as some species of turtles, use them for food. At times they, along with fragments of larger plants, are washed upon the shore where they decay, forming a soft black mud. More important, but generally less conspicuous, are the minute algae barely visible to the naked eye and including many of the blue- green colonial forms, the diatoms, desmids, etc. By far the greater number of these minute forms, like the coarser algse, stay near shore, either because they are attached to or generally more or less entangled, among other growths, or, to sum up all in one sen- tence, because they find the best conditions for life there. These are the so-called limnetic forms. Others, however, stray far out from shore and are driven hither and thither by the winds, waves and currents; these form the vegetable part of the plankton or phyto-plankton and affect the lake in various ways. They give the water, in a certain sense, its optical quality, just as minute specks of dust and motes give the air what might in an artistic sense be called its "atmosphere" — its blueness or grayness and so on. Moreover it is upon these plankton algse that the newly hatched fish all feed, either directly or indirectly, by feeding upon the small animals that feed upon it; and again when the plankton algse be- come too abundant they rise to the surface and form a disagree- able and ill-smelling scum which appears to affect some people who "go swimming in dog days" much as a mild case of ivy poisoning might. And they render the water of some reservoirs so rank and unpalatable that they become a nuisance for which dosage of the affected water with copper sulphate was devised as a remedy. The free floating forms of algse were collected by means of va- rious sorts of plankton nets, one so constructed as to take vertical hauls showing the vertical distribution of the organisms captured, the others, towing-nets taking horizontal hauls along the surface. Many of the algse, especially the coarser ones, along with attached or entangled diatoms and desmids were collected by hand along shore. The charas were all gathered by hand or dredge. 140 Lake Maxinkuckee, Physical and Biological Survey The algae obtained by the plankton hauls of 1899 and 1900, along with a few others collected by hand were identified by Dr. George T. Moore, then associated with Dartmouth College, later of the U. S. Department of Agriculture, now the Director of Mis- souri Botanic Gardens, and the originator of the scheme of keep- ing the algse within bounds by the use of copper sulphate. A part of the diatoms collected in the plankton hauls of 1901, as well as various samples of hand gathered material, were identi- fied by .Dr. Albert Mann then of the U. S. Department of Agricul- ture, now of the Carnegie Institution of Washington. Some of the alcoholic Characeaa material sent along with the plankton were identified by Dr. George T. Moore, while much of the alco- holic and all the dried Chara material was kindly identified by the late Prof. C. B. Robinson of the New York Botanic Garden. We wish here to express our appreciation of the assistance so gener- ously renedered by these specialists. During the summer and autumn of 1906 a fair number of tow- ings and hand collections were made, 113 in all, in all sorts of con- ditions, chiefly about shore. This material has been very hastily examined and a number of the more easily recognized forms identi- fied, leaving a large number of the more critical species untouched. Much of the coarser algae obtained were unfortunately sterile, and the species accordingly problematical; they show a great diversity of species and suggest a very interesting and fruitful field for col- lection and research. The collections taken in the various plankton hauls of 1900 and 1901 are so very similar that a general statement will suffice, leav- ing any individual peculiarity to be considered in the discussion of the species. The following are the most abundant plankton species, having been taken in almost every haul: Lyngbya aestuarii Liebmann, Coelosphaerium keutzingianum Naegeli, Anabaena flos-aquae Brebisson, Eremosphaera viridis de Bary and Ceratium macroceras Schrenk. Among the less common forms are Pedi-astrum boryanum Meneghini, occurring in seven hauls, Oscillatoria tennis Agardh, taken once, Peridinium tabulatum Ehrenberg, taken twice, and Chlamydomonas reticulata Gorosch, taken three times. The spe- cies represented are rather few in number, and the work of examin- ing the material may be aptly described as monotonous. In the dis- cussion of the alga?, the plankton forms are not discussed sepa- rately, but are considered along with other species that do not enter into the plankton. Lake Maxinkuckee, Physical and Biological Survey 141 ANNOTATED LISTS OF SPECIES THE GREEN AUGJE, ETC. 1. CHROCOCCUS TURGIDUS (Kuetz.) This is not a plankton alga, and occurs under such circum- stances that it can not be obtained by wholesale methods. It was obtained only once, in hand-gathered material along the shore of the lake, along with such forms as (Edogonium, Bulbochsete, etc. Its natural habitat is in springs, and it is probably fairly common about the edges of the lake and the numerous springy places. 2. GLOEOCAPSA MAGMA (Bieb.) Encountered only occasionally, especially in the stomachs of mussels obtained along the shore of Lost Lake. 3. GLOEOCAPSA POLYDERMATICA Kuetz. Forming a crinkled, gelatinous blue-green mass near Culver, August 30, 1906. 4. MICROCYSTIS AERUGINOSA Kuetz. This species, which is excessively abundant in Winona or Eagle Lake, Kosciusko County, is rather scarce in the plankton of Lake Maxinkuckee; a few colonies occasionally found in some of the towings near shore. It is probably more abundant in Lost Lake — a shallow lake with muddy bottom more like Eagle Lake in character. A note of Sep- tember 7, 1908, says : "It is this which makes an exceedingly fine granular scum, easily thrown into fine lines ; abundant on Lost Lake among rushes, and some on sand at the edge of the lake." It is very abundant in some of the weedy lakes north of Lake Maxin- kuckee. At the latter lake it is very frequently encountered as an element of mussel food. This species is, perhaps, more widely known under the name Clathrocystis, the question of names being in this case a matter of opinion. West, with whose opinion we concur, says, "the three genera, Microcystis, Polycystis and Clath- rocystis, are not sufficiently distinct to warrant their separation. The differences between them are only differences of degree." 5. GOMPHOSPHAERIA APONINA Kuetz. Not frequently obtained in towings or hand-gathered material, but a rather common element of the mussel food. The mussel makes one of the most efficient substitutes that could be utilized for a towing-net or plankton collector. 142 Lake Maxinkuckee, Physical and Biological Survey 6. COELOSPHAERIUM KUETZINGIANUM Naeg. A frequent element in the plankton, occurring in almost every haul, both the vertical and towing-net hauls. Along with much of the other plankton algae it was a common element in the food of the freshwater mussels of the lake. 7. MERISMOPEDIA GLAUCA (Ehren.) This is not a plankton alga and was usually found not far from shore. It was occasionally found in material collected in Outlet Bay not far from shore, and was taken in connection with Oscil- latoria, (Edogonium, Bulbochaete, etc. This delicate plate-like form is not well adapted for preservation and is best recognized when fresh material is studied in the field. 8. APHANOTHECA STAGNINA (Sprengel) Although very abundant in parts of the lake, this species does not enter into the plankton but remains lying scattered over the bottom, especially where it is peaty and firm, in the form of tough blue-green jelly-like balls about the size of peas or larger. Some was collected near shore August 29, 1900, and on the northwest shore of Lost Lake, September 4. When placed in a vial of fresh water it does not die and decay, as do most of the algas, but re- tains its bright color and emits no odor. The colonies remained unchanged through the winter and were frequently noted through the ice, lying on the bottom. In the bot- tom of Outlet Bay, a little way out from shore the ground, a tough, peaty soil, appeared to be covered with small pebbles from the size of hazelnuts to a trifle larger. Upon scooping them up they proved to be Aphanotheca. Some of the colonies were dark blue-green, others more brownish or yellowish. We know nothing of its re- lationships with the organisms of the lake. 9. RIVULARIA NATANS (Hedw.) Rare in the lake ; not found in the plankton, and obtained only once, in hand-gathered material from Outlet Bay, October 12, 1900. 10. RIVULARIA ECHINULA (Smith) Rare; a little found tangled up in brown and blue-green fila- ments obtained from the south end of the lake, August 11, 1906. It resembles pretty much the Rivularia natans which is so abundant, free-floating, in Bass and Chapman lakes. One filament in the colony examined showed the saccate base of "Gloiotrichia" which, however, was not subdivided. The colony looks much like Apstein's figure. Lake Maxinkuckee, Physical and Biological Survey 143 11. RIVULARIA DURA Roth Not a plankton-alga; obtained from hand-gathered material. The following is a note on the Weedpatch vegetation, August 28, 1900 : "All these plants are covered thickly with Rivularia, some in quite large colonies. It was also found on Chara, collected the same date. On September 12 (1900) sticks in Lost Lake were thickly covered with globular brownish-black beads of Rivularia and bright green beads of Chsetophora. A good deal of Rivularia was noted, attached to Potamogetons at McSheehy's pier, Septem- ber 20. Rivularia is one of the most abundant algse in the lake, thickly dotting stems and leaves of water-plants with brown or blue-green hemispherical gelatinous masses about the size of a pinhead or somewhat larger. It is, indeed, at times difficult to find an example of water plant in the lake which is not more or less thickly dotted with these colonies. It is found the year round, but is probably more abundant in summer. It is never found free-floating in the lake. It is probable that fishes sometimes nibble it off the leaves, especially off the Chara where it stands out in bold relief. In the collections it appears associated with (Edogonium, Bulbochaete, Oscillatoria, etc. 12. RIVULARIA HAEMATILES Agardh Like the other species, this is not a plankton alga ; it is probably not common, and was obtained on only two occasions, once Septem- ber 12, and again on September 29, 1900. We have no notes con- cerning it except the records of its occurrence. 13. CALOTHRIX FUSCA B. & F. Not a plankton alga but obtained by hand-gathering along with Chaetophora, Cladophora, etc., and various desmids. Fairly com- mon and well distributed near shore. 14. SPIRULINA JENNERI Kuetzing Very common in a red, gelatinous coating on west shore by Chadwick's, August 13, 1906, with Anabaena stagnalis and Proto- coccus. The exceedingly slender filaments have a peculiar spiral appearance. 15. OSCILLATORIA TENUIS Ag. Not common ; obtained in one of the vertical plankton hauls and represented in four other collections. It was probably more com- mon in the neighborhood of Norris Inlet. Floating, black, slimy masses, composed of Oscillatoria, may occur now and then in the lake, one such being observed September 12, 1900. 144 Lake Maxinkuckee, Physical and Biological Survey As a general thing the Oscillatorias grow on wet ground form- ing dense mats along the shores of rivers and lakes. With a sudden rise of the water they are lifted loose and float until they find suitable resting places. In August, 1906, Oscillatoria, prob- ably this species, was observed forming a firm bottom stratum on the bottom where the road north of Green's marsh passes along the lake shore. 16. OSCILLATORIA MAJOR Vaucher A large, stiff, straight Oscillatoria, probably this, was abund- ant (August 6, 1906) on mud at the edge of the lake and in shallow water, along the northeast shore of the lake where the public high- way borders the lake. 17. LYNGBYA ^ESTUARII Liebman The Lyngbya found at Lake Maxinkuckee is the form described by Walle as L. obscura, which is regarded as a synonym of sestuarii. It is an almost constant element in the vertical plank- ton hauls made at the stations. While not generally conspicuous in the plankton scum it sometimes collects pretty thickly along shore in sheltered places, among rushes on calm days. It is not nearly so common at Lake Maxinkuckee as at Winona Lake near War- saw, where it was seen diffused through the water in great quan- tities, resembling stiff hair-clippings. In addition to. being obtained in the vertical hauls, this was often taken in the towing-net; it was also often simply skimmed off of the surface of the lake when it formed masses of scum along shore. In this manner quantities were obtained August 28, 1900, and again on August 29, the material obtained August 29 being dark brown in color, due to its condition, the sheaths frequently projecting beyond the cells, some of the latter having escaped. Au- gust 31, 1900, large patches of blue-green scum washed up against the west shore of the lake proved to be composed of this. On the afternoon of September 1, large, brown filaments of this were found covered with diatoms. On September 4 there was a brown scum near Arlington Hotel composed of this, Anabsena, Microcystis and Statoblasts. A thick scum was also observed September 13 and 18. None was observed during the spring of 1901, it being more abundant and conspicuous in the autumn. In the late summer and autumn of 1906, hauls were frequently made with the towing-net from the Chadwick pier across to the ice-office. On July 26, when first observed, it was noted as not rare in a scant haul made. It was actively forming hormogonia, or breaking up into reproductive fragments, but not present in appreciable quantities in the lake. Lake Maxinkuckee, Physical and Biological Survey 145 On July 28 it was still scarce. By August 8 it was abundant, a large quantity being obtained in a towing in Outlet Bay. It was noted again on the 16th. On August 21, on a visit to Winona Lake, a towing was made and it was observed that filaments there were longer and more abundant than at Lake Maxinkuckee. On Sep- tember 28 the plankton taken in Outlet Bay was a dirty brown fibrous mass, composed mainly of the empty sheaths of the fila- ments of this species, the interior cells having mostly escaped to make new independent colonies or filaments. By noon of the same day the quantity of this species had so greatly increased in the lake that it was evident to the eye. On September 5 it was still form- ing hormogonia. The stomach of a small painted turtle examined in Septem- ber, 1906, contained Lyngbya in such quantities that it must have been taken in intentionally, although it is difficult to explain where the turtle had obtained so much. Examinations of the stomachs of these turtles have shown that they partake largely of various algae; indeed, algas seem at times to furnish the turtles' main diet. The rapid increase of Lyngbya during the late summer and early autumn months is due to its excessively rapid reproductive process which is simply the slipping out of short portions of fila- ments and occasionally single disc-shaped shells from the sheaths of the old filaments. We know little about the part this species plays in the economy of the lake. It never appears, even in its greatest abundance, to become a positive nuisance. Entomostraca may, and mussels do, feed upon the shorter filaments, but the longer filaments are un- handy for most of the plankton-consuming organisms except the painted turtle. 18. APHANIZOMENON FLOS-AQILS (Linnzeus) On August 4, 1906, some was taken with the No. 2 towing- net in front of the ice-office. Taken also in Lost Lake, but it does not appear to be common. This is the most common plankton element in some of the lakes of Minnesota and is abundant at times in the upper Mississippi. The waters of reservoirs sometimes seem almost thickened with it. 19. ANAB^NA FLOS-AQU/E Brebisson This is the most abundant plankton species of the lake, it having been taken in almost every haul of the plankton net during 1899 and 1900. During 1900 and 1901 plankton-scum quite frequently accumu- 10- -17618— Vol. 2 146 Lake Maxinkuckee, Physical and Biological Survey lated along- the shore in sheltered places, usually in rather small amounts, however. It was only occasionally collected and only a few notes were made concerning it. Anabsena was almost always present, but apparently did not make up the main mass. During the summer of 1906 — a calm, dry summer — the plank- ton-scum was present in unusual abundance and was made up chiefly of this species. It was frequently examined, so that the species was under pretty continuous observation for that year, and its history is nearly the same as that of the scum in general. On July 30, 1906, on a trip to Norris Inlet it was noticed that the water of that region was full of diffused minute blue-green flecks. Hauls were made with the towing-net but nothing was ob- tained but duckweeds. The fine, flocculent material was probably Anabsena. It was found later that it readily strained through the finest towing-net on hand. The next day the water of the lake seemed full of suspended algse. A towing was taken in the morning from Long Point (Chad- wick's) to the office, and many entomostraca were taken, but the small algse escaped. At noon the water by the office seemed very full of the same material and dips were taken with the fine net, but nothing much was obtained; the fine algae again escaped. In the afternoon of the same day a fine blue scum, the first of the year, was observed in a minnow-box. This was secured by dipping with a vial, and proved to be Anabsena. About 2 o'clock the scum was quite pronounced, first in a ditch-like artificial channel (boat slip) , dug into the shore in the south side of Outlet Bay, the excava- tion being 15 or 20 feet wide, and 80 to 100 feet long, forming a calm, sheltered harbor. Somewhat later in the same day, the scum gathered thickly in front of the office, and was collected and examined. In this particular instance the appearance was somewhat dif- ferent from usual ; the scum was composed of minute dark green balls in active motion, somewhat resembling minute colonies of Volvox except for the darker color. On examination the material was found to be composed of dense balls of tangled Anabsena fila- ments, almost every ball surrounded by a halo of attached Vorti- cellas, the contractions of which had caused the motions of the mass. The appearance of the balls with the radiating, jerking Vorticellas was quite striking. From this time on until late autumn, scum composed mainly of Anabsena, was present in considerable quantities somewhere along shore every calm day, and on some days covered the whole lake more or less completely (August 6 and August 7). It frequently Lake Maxinkuckee, Physical and Biological Survey 147 occurred on the surface ranged in fine parallel lines, into which it had been thrown by undulations of the water surface. Anabsena, after having been often seen, can easily be dis- tinguished in the water by the naked eye, its peculiarities of color and structure rendering it distinguishable from the other plankton- algse. Both its appearance in mass and its microscopic appear- ance differ somewhat under different conditions. Soon after coming to the surface and forming a scum, especially after forming a dense scum along shore, it changes in color from dark blue-green to very pale blue, and the dense, tangled balls disintegrate into single coiled filaments. In many cases great, thick masses were formed along shore, especially in the bay southeast of the Academy along the road, and then the algse apparently died. The water in the vicinity became whey-like in appearance, and the mass had a rank vegetable odor, so persistent that it remained after the addi- tion of considerable formalin to vials containing the specimens. A vial of the live material placed in the hot sun appeared to die soon ; the water became decidedly milky and the cells became colorless. As the alga is known to disappear during the winter, close watch was kept of the scum during the later part of the season to observe what became of it. Late in the autumn it was found to have sunken to the bottom along shore and was being covered up by the forest leaves which fell into the water and sank to the bottom. So far as observations go, it is not known whether this species furnishes much food to the various animals of the lake or not. It is a form which would be difficult to recognize in the stomach of any animal, as the teguments are thin and the cells quickly sepa- rate from each other, their attachment being weak. Because it forms a scum on the surface of the lake and along shore, this plant is to some slight extent a nuisance. Its presence in great profusion, as well as its unpleasant odor, detracts some- what from the appearance of the lake. There is a prevalent no- tion about the lake that the plankton-scum is poisonous, the effect of it being to produce intense itching where it touches the skin. No cases were observed, and no unpleasant sensations were ex- perienced, however, and the few cases heard of which could be reasonably authenticated might very likely be attributed to some other cause, or to especial sensibility of the persons affected. Its exceptional abundance during the summer of 1906 was followed by an exceptional abundance of entomostraca in the au- tumn of the same year, and it is possible that there was some con- nection between the two. 148 Lake Maxinkuckee, Physical and Biological Survey Apstein (Siisswasserplankton, p. 136) gives a figure and notes on the life history of this species. He found it abundant in various places examined. He says nothing of its being eaten by pelagic organisms. In his description of its wintering over he says : "At the end of summer the spores are formed in abundance, which sink to the bottom and here rest until the next spring. Many are naturally eaten by the animals of the bottom, since in them the nutritiveness is much concentrated." His figure shows numerous Vorticellas intermixed with the fila- ments; it is probable that the same relation exists between them here as above noted. 20. ANAB^ENA STAGNALIS Kuetzing Common in a red film or scum coating the wet shore by Chad- wick's, August 13, 1906, along with Spirulina jenneri and Proto- coccus. Some of the filaments were much knotted and coiled. 21. ANAB^ENA SACCATA (Wolle) Off Assembly grounds, August 8, 1906, collected by hand ; form- ing finger-like lobate blue-green masses in great abundance in shal- low water near shore. Quite unlike the other species of Anaba?na, and put in a different genus by different authors, — West in AnabaBna, Wolle in Sphserozyga, and Bornet and Flahault in the genus Wollea. 22. NOSTOC VERRUCOSUM Vaucher Not a plankton alga, but represented by hand-gathered mate- rial. Green's marsh and the quaking, boggy plain west of Lost Lake contained an abundance of Nostoc in the form of beads of blue-green, at times almost black, firm jelly ranging from the size of a pinhead up to nearly the size of a hazelnut. On March 23, 1901, a film of this material was noted in Green's marsh, and on March 25 in the same place old Nostoc balls were noted shrivelled up, looking much like dried grapes. Almost any time of the year these globular colonies of Nostoc can be found in abundance near the moist base of grasses and sedges in the flat, sedgy plains about the lake. 23. TOLYPOTHRIX TENUIS Kuetzing Not a plankton alga, and not obtained in the lake, but procured in the bottom of the woodland ponds, along with Draparnaldia, Tetraspora, etc., in hand-gathered material. Probably common in the woodland ponds where algae of many forms luxiuriate on the bed of old leaves forming the bottom of the pools. Lake Maxinkuckee, Physical and Biological Survey 149 24. BOTRYDIUM GRANULATUM (Linnaeus) Noted growing abundantly on the surface of cracking, moist mud at the shore of one of Zechiel's ponds, the plants having the appearance of small green shot. 25. TRIBONEMA BOMBYCINUM (Agardh) Abundant along shore and common in numerous shore collec- tions along with Hydrodictyon, Spirogyra, (Edogonium, etc., prob- ably helping form the great mass of algae along the shore near the Outlet. 26. TETRASPORA LUBRICA (Roth.) Not found in the lake at all but very abundant in spring in woodland ponds on the dead leaves which formed the bottom, where it was collected by hand (April 27, 1901) , along with Draparnaldia, Tolypothrix and Zygnema. Our material was from a small pond near Farrar's. It is probably common in parts of the lake at cer- tain seasons. 27. BOTRYOCOCCUS BRAUNII Kuetzing Quite abundant in the plankton scum during the summer and autumn of 1906, mixed in with a great amount of Anabaena flos- aquae which formed the main mass. The colonies were of two col- ors, yellowish green and bright red. On account of its vivid color and commonness the plant excited an unusual interest and it was studied somewhat in detail. The following notes were made: Colonies rather solid, irregularly lobed masses, a rather large colony measuring 250 x 120 mic. Margin of colony with minute but blunt- ish, sometimes clavate, projections. In fresh material the structure of the colony is difficult to make out satisfactorily on account of the diffiused red color which renders it opaque. A colony of formalin material was kept in a moist chamber for several days and much of the coloring matter dissolved out in the form of oil-like orange- red drops, leaving the margins of the thallus paler. The thallus was then seen to be a firm mass containing rather widely separated oval or ovate lacuna? (diameter of lacunae 7-10 mic. separated by spaces 7-10 mic. wide) . The vegetable cells had escaped from the lacunae and were ovoid or pear-shaped, measuring about 7 mic. across the short axis and 12 mic. along the long axis. No cilia were visible. On account of its vivid color this species can be recognized quickly among heterogenous material. It appears to be eaten in considerable amounts by various entomostraca, the stomach con- tents of which are colored red by it. 150 Lake Maxinkuckee, Physical and Biological Survey 28. DICTYOSPHJERIUM EHRENBERGIANUM Naegeli Not a plankton form; staying near shore and obtained in hand- gathered material along with Oscillatoria, Rivularia, (Edogonium, etc. It occurs in only one sample. 29. TETRAEDRON MINIMUM (A. Braun) Common among material found in the contents of mussel stom- achs along with Scenedesmus, Pediastrum, etc. On account of its small size it is easily ingested by the mussels. 30. CHORELLA sp. Common, associated with Ophrydium, which is one of the most abundant protozoans in the lake. 31. EREMOSPH^ERA VIRIDIS de Bary A common element of the plankton occurring in most of the vertical hauls at the established stations. It is said to be "a con- stant associate of certain desmids" in the British Isles, where it is especially common in Sphagnum bogs. 32. ANKISTRODESMUS sp. Various forms of Ankistrodesmus are common elements of the mussel food. This genus is perhaps better known under the name Rhaphidium. 33. SCENEDESMUS ABUNDANS Kirchner Various forms of Scenedesmus, especially abundans and obliquus, as well as numerous forms for which no descriptions or figures could be found, were abundant elements of mussel food. Indeed, along with Pediastrum, they may be regarded as the most charac- teristic elements of the mussels' bill of fare. They were especially common in Lost Lake. 34. SCENEDESMUS OBLIQUUS (Turpin) Common in towings taken near the shore. 35. CRUCIGENIA TETRAPEDIA (Kirchner) Rare ; only a few colonies seen mixed up in collections of minute algse. Its striking appearance, a flat plate composed of an aggre- gation of minute green maltese crosses arranged in regular order, attracts attention at once. 36. SORASTRUM sp. Not a rare plankton element along the edge of Lost Lake, where it is occasionally taken in as food by the mussels. Lake Maxinkuckee, Physical and Biological Survey 151 37. CCELASTRUM MICROPORUM Naegeli Common in plankton hauls along shore, and a frequent element in the material forming the food of mussels. 38. CO2LASTRUM SPH^ERICUM Naegeli Probably common along shore and quite frequently found in the algal mixtures taken from mussel stomachs. 39. PEDIASTRUM BORYANUM (Turpin) Occasional but not abundant, occurring in a number of the ver- tical plankton hauls and now and then in towings along shore. Usually only one or two taken in a gathering. The mussels are the best collectors of Pediastrum, almost every stomach examined con- taining from one to several examples. 40. PEDIASTRUM DUPLEX Meyen Occasionally taken in towings near shore. Variable in length of horns, etc. Characterized by the perforate disk. Like the other Pediastrums it appears to be a favorite food for mussels; indeed, the best way to obtain examples of Pediastrum is to examine the intestinal contents of mussels which almost always have present representatives of some of the species. 41. PEDIASTRUM EHRENBERGII (Corda) Not common ; a good example obtained among algaB in the Out- let near the bridge on July 23, 1906, among the marl-like blue ma- terial. In general form the example found agrees with Wolle's figure (Desm. U. S. PI. LIII, fig. 25) of the 4-celled phase of this species, but differs markedly in the inner cusps of the cells, which are bluntish. Diameter of the ccenobium 18 mic. It is probably the young of the variety represented by Wolle's fig. 27. A peculiar form of what appears to be this species is rather common in the lake, and reaches a large size. Its most striking peculiarity con- sists in having the interior cells of the colony retain their horns in a rudimentary form so that each cell has a markedly concave side. This form is most frequently found along shore where the bottom is shallow and the bottom more or less a black mud, as at Norris Inlet and the Outlet. 42. HYDRODICTYON RETICULATUM (Linnaeus) Not taken in plankton but represented in a hand-gathering along with Spirogyra, CEdogonium, etc. Not especially common about the lake; indeed, not so common as one might naturally expect, but 152 Lake Maxinkuckee, Physical and Biological Survey found growing quite abundantly and constantly in the mouth of the small creek under the railroad bridge at Culver. In its habits of reproduction one of the most striking of the algae, not differing in manner from Pediastrum but on such a large scale that the phe- nomenon is striking, the whole mass giving birth to minute colonies, the adult form in miniature. In time of freshets, these minute new-born colonies may be washed out a considerable distance into the lake when they become a part of the plankton, but their normal habitat is near the shore of lakes, although they may cover thickly the entire surface of small ponds, forming dense masses. In 1906 (July 21) it was noted as being very abundant near Chadwick's. 43. GONIUM PECTORALE Miiller Not common ; one example found in the Outlet, August 13, 1906, a 16-celled colony. Diameter 38 mic., individual cells 10 mic. in diameter. Crenobium in active motion when observed. 44. CHLAMVDOMONAS RETICULATA Gorosch Occasional in plankton hauls in July and August; found in the plankton far out in the lake. 45. DESMIDIUM SCHWARTZII Agardh Rare in the lake, obtained only once in a shore gathering of heterogeneous material. 46. DESMIDIUM QUADRATUM Nordstedt Common in Hawk's marsh where it grows among other fila- mentous algae in the form of long filaments. Obtained September 14, 1906. Almost all algal gatherings from Hawk's marsh con- tained this form in abundance. 47. STAURASTRUM BREBISSONII Archer Taken in several plankton hauls and evidently found farther out from shore than most desmids. A fairly common element in mus- sel food. Several other forms of Staurastrum were encountered in the mussel food, but were not identified. 48. COSMARIUM GRANATUM Brebisson Only a few obtained in shore gatherings of miscellaneous ma- terial. 49. COSMARIUM LATUM Brebisson Obtained in a mass of weeds (Naias and Chara) collected at Long Point, near shore, July 24, 1906. Lake Maxinkuckee, Physical and Biological Survey 153 50. COSMARIUM INTERMEDIUM Delpontc Found in some fine, fibrous material obtained at the ice-houses, July 23, 1906, the material being gathered for the rich amount of diatoms it contained. 51. COSMARIUM SUBCRENATUM Hantzsch In a mass of tangled Cladophora collected along shore. 52. MISCASTERIAS TRUNCATA SEMIRADIATA Naegeli A fine example obtained from the south end of Lost Lake, July 30, 1906, along with various diatoms, Pediastrum and Scenedesmus. An unusually handsome desmid. 53. DOCIDIUM VERRUCOSUM (Bailey) Apparently rare. Obtained only once, in a collection along shore. 54. CLOSTERIUM DIAN^E Ehrenberg Frequent in surface plankton hauls near shore, especially in the region of Norris Inlet. 55. SPIROGYRA CONDENSATA (Vaucher) Obtained in several hand collections along shore with Hydro- dictyon, (Edogonium, Ulothrix, etc. Found in fruit in autumn. The genus Spirogyra is represented by numerous species in and about the lake. Sterile filaments could be obtained abundantly at all times of the year. Lost Lake, the Inlet region, Outlet Bay and Culver Inlet on the Academy grounds were luxuriantly overgrown with filamentous algae of all sorts, the growth in the Academy grounds being especially luxuriant. Attempts were made to pro- cure as many species as possible, but the difficulty of obtaining fruiting specimens, especially with the pressure of other work and interests, made it impossible to get a representative collection. The task of making a complete or anything like a complete collection of these algae is a great deal different from that of collecting float- ing forms where such wholesale methods can be used as towing- nets, etc., and would require the undivided attention of a specialist. In the economy of the lake, the coarse filamentous algae belong rather with the pondweeds than with the plankton. They are prob- ably eaten to some extent by herbivorous fishes, and certainly fur- nish a good deal of turtle food, especially to the painted turtles, which feed upon them to a considerable extent. There is, perhaps, a darker side to their case. One of the dwellers of the lake region called them "malaria." We found that Chironomus larvae eat them greedily and in all likelihood mosquito 154 Lake Maxinkuckee, Physical and Biological Survey larvae also. Whether their great abundance goes hand in hand with the prevalence of malaria is a question yet to be investigated. Sterile filaments were collected with a diameter of 29 mic. and length of cell of 174 mic. ; probably Spirogyra quadrata; another with a diameter of 33 mic. and length of 140 mic. with 3 spiral bands ; another with the cells measuring 35 x 105 mic. with only 1 spiral band; a fourth with cells measuring 65x205 mic. and 2 spiral bands; a fifth with cells 80 mic. in diameter and 75 mic. long and 2 bands ; a sixth with cells measuring 70 x 125 mic. and 4 bands; a seventh with a diameter of 70 mic., cell-length 200 mic. and 3 bands; an eighth with cells measuring 125x220 mic. The coarse Spirogyras of Lost Lake were noted conjugating in early spring and a special trip was made a few days later to col- lect them but they had produced spores, disintegrated, and dropped to the bottom. Among many forms of Spirogyra noted at the lake which could not be identified satisfactorily on account of having not been in fruit, the following may be mentioned: 56. SPIROGYRA MAJUSCULA Common along shore by the ice office; frequently left in pools along the shore by the receding water. The filaments left in the pools soon conjugated and formed fruit. Found with ripe spores August 7, 1906. 57. SPIROGYRA MIRABILE Hass Found conjugating among a lot of fine filamentous algse gath- ered by hand along the east shore of the lake, August 8, 1906. 58. ZYGNEMA sp. Zygnema is fairly common in the lake during the summer. Most of our species are more slender than Spirogyra and form yellowish green masses floating far out in the lake, and not clinging closely to shore as most Spirogyras do. It was common in Lost Lake and abundant in the shallow water near the ice-houses. None was found in fruit. 59. MOUGEOTIA sp? This was quite abundant, especially in the shallower portions of the lake, as in Outlet Bay and Lost Lake. Sometimes it grew abundantly in great masses in the bottom, attached or rather tangled up with short plants. Frequently it floated in large yellow- ish-green, loose masses. It seems to thrive best when the water is rather warm, though it often persists until late autumn, making Lake Maxinkuckee, Physical and Biological Survey 155 cloudy masses in the bottom in shallow water. In 1906 (July 24) considerable was seen in Lost Lake attached to plants, by being tangled up with them. 60. VAUCHERIA sp. Abundant, forming thick, darX green, felted masses in the bot- tom of shallow ditches near the lake, and more especially on the surface of saturated ground near Overmyer's spring. Not found in fruit. There may have been several species. Not found in the lake itself. 61. CLADOPHORA FLOTOWIANA Collected in the Inlet, July 30, 1906. Fruiting cells large and clavate. 62. CLADOPHORA GLOMERATA (Linnaeus) Abundant in the lake, forming dense tufts growing attached at the base to submersed stones along the shore; most abundant along Long Point and off from the Depot pier. The dense tufts furnish hiding places for numerous small larvae, snails, beach fleas, caddis-cases, etc. Filaments are frequently thickly beset with the parasitic diatom Cocconeis pediculus. 63. PRASIOLA PARIETINA (Vaucher) Found in a single shore collection of miscellaneous material, such as Utricularia, Conferva, Chaetophora, etc. 64. MICROTHAMNION sp. A dichotomously branching slender alga, found abundantly in shallow water around the margin of Lost Lake in the spring of 1901, the basal portion being attached in the mud. It closely re- sembles West's figure of M. strictissimum Raben. 65. DRAPARNALDIA GLOMERATA (Vaucher) Not found in the lake in great quantities but growing thickly on submerged dead leaves in the bottom of woodland ponds in the spring. Obtained from a pond near Farrar's, April 24 and 27, 1901. A considerable quantity was seen along a ditch west of the lake. It thrives best in cold water and for that reason is generally seen only early in spring. A little was collected in the lake May 25, 1901. 66. MYXONEMA RADIANS (Kuetzing) Found in Norris Inlet, July 30, 1906, attached to Cladophora. (As has been pointed out by Hazen, the familiar name Stigeo- clonium Kuetzing should be replaced by the older name Myxonema Fries.) 156 Lake Maxinkuckee, Physical and Biological Survey 67. CH^TOPHORA PISIFORMIS (Roth) Abundant in both lakes, attached to dead, submerged sticks, especially where the bottom is muddy but the water clear, form- ing little bright-green globules flattened on the attached side, closely resembling Rivularia with which it is associated, except in color in which it forms a distinct contrast. As it is an attached form it does not enter the plankton net. 68. CH^TOPHORA INCRASSATA (Hudson) Frequent on mucky or turfy bottom, especially common along shore in the neighborhood of the Inlet region. A long, irregu- larly, or dichotomously branching, ribbon-like bright green form resembling in shape the liverwort, Riccia fluitans. It is found the year round but is probably more abundant in the spring. 69. SCHIZOMERIS LIEBLEINII Kuetzing Abundant in the region of Norris Inlet, attached to the sub- merged parts of bulrushes, water-lilies, pond lilies, etc. It stands in strong contrast with the other filamentous algaB of the lake by its complex multicellular structure. To the naked eye it bears a considerable resemblance to a coarse Spirogyra. 70. ULOTHRIX ZONATA (Webber & Mohr) Common in a mass of fine blue-green algse taken from the stems of the yellow pond lily Nymphsea advena, July 30, 1906. 71. ULOTHRIX TENUISSIMA Kuetzing Obtained in hand-gathered material along shore August 30, 1900, along with Lyngbya, Spirogyra, and diatoms. 72. COLEOCHOETE SCUTATA Brebisson Found abundantly in the lake attached to fragments of drainage tile that were lying in 18 inches of water a little north of the ice offices. The plants were observed in August, 1906. 73. BULBOCH^TE PYGM^A (Pringsheim) Fairly common in the lake attached to weeds and other algse. 74. CEDOGONIUM BOSCH (Le Clerc) One of the most abundant of the attached algse of the lake, growing abundantly on rocks and pebbles, and attached to sub- merged plants, forming a dense, lemon-green fine hair-like growth over the substratum. Although very common, its small size as compared with the Cladophoras and Spirogyras renders it rela- Lake Maxinkuckee, Physical and Biological Survey 157 tively inconspicuous. It grew very abundantly at Long Point, both on stones and weeds, and was found attached more sparsely to weeds in other places, as at Kruetzberger's pier. At Long Point, after the water had retreated from the rocks where this alga had been growing, it died and bleached out, leav- ing a firm, linty covering on the rocks. The specimens agree very closely with Wolle's figures of lands- boroughii, but are considerably more slender than given in his de- scription, the following being the measurements : Length of cells 62 mic., diameter 22 mic., the younger being 55 mic. long and 20 mic. in diameter. Oogonium, diameter 45 mic., length 65 mic. Egg cell, diameter 30 mic., length 50 mic. Male filaments somewhat more slender. Spermogonia usually 7 or 8. The plants fruited abundantly during the summer, the oogonia being frequently two or three in succession, green when young, rich brown when ripe. Terminal cell blunt, opening of oogonium above the middle. 75. CEDOGONIUM LONGATUM Kuetzing A dwarf species, common at Long Point, attached to other algae. 76. CEDOGONIUM LANDSBOROUGHII (Hass.) Common in filamentous material gathered for diatoms near Kreutzberger's pier, July 24, 1906. Male plants uusually called spermogonia common. THE CHARACE^E One of the first things to attract the attention of the visitor to the lake who is interested in the aquatic flora is the abundance and variety of the peculiar and attractive group constituting the Characese. The greater part of the shallow bottom of Lake Max- inkuckee from a foot or 18 inches to 8 or 10 feet, is covered with a stout Chara 8 or 10 inches high, yellowed or browned with an in- crustation of lime and forming a dense mat over most of the bottom like a brown, subaqueous meadow. A visit to Lost Lake but intensified the impression produced by Lake Maxinkuckee. The subaqueous meadow was lacking, in- deed, but the shore was lined with various strange forms, some of them with a silky softness as compared with the harshness of most common forms, the plants bushy with an abundance of slender, delicate leaves and glowing with an abundance of red fruit, while in the depths of the lake, arising from the black mud, were long, slender, semitransparent forms, and others strong, robust and 158 Lake Maxinkuckee, Physical and Biological Survey bristly. In Green's marsh between the lakes other species throve, maturing their fruit early in the year in the shallow warm ponds. The Charas form so important a part of the lake flora that no labor was spared in an attempt to get an abundance of specimens of all sorts in fruit. According to ancient custom much of the material was pressed and made into herbarium material, while other material was preserved in alcohol and formalin ; which is the better way, it is, of course, for curators in museums to decide. The herbarium specimens fit in well with other botanical material and take up but little room, but some are so brittle that they usually break to fragments with but little handling. The Charas are an important part of the life of the lake; by their abstraction of the lime from the water they do much to add to its softness, and by the deposition of that same lime on the bottom they do much to add to the marly bottom of the lake bed. They furnish hiding places for various species of fish, the mad- toms and darters inhabiting them throughout the year, and the young bluegill, redeye, etc., hiding in them throughout the winter. A number of important animals used by the fishes for food, such as beach fleas, Asellus, etc., live among the Chara, and it is among the Chara patches that the bluegill, perch and various sunfishes usually stay during the spring months, feasting upon the abundant life to be found there. The ducks and coots, after the more deli- cate plants such as wild celery have been exhausted, feed upon the Chara. The Characese were submitted to various specialists for identifi- cation, the herbarium material to the late Dr. C. B. Robinson, and the alcoholic material along with the plankton to Dr. George T. Moore. Many of the specimens on account of their variability were difficult to determine satisfactorily. Indeed, there have been so few workers in the field and relatively little material collected over the country generally that classification is exceedingly difficult. The following notes on the various species are given : 1. CHARA CONTRARIA A. Braun This is the most common Chara in the lake, forming the ex- tensive meadows over the bottom. On account of its abundance it is the most important Chara of the lake. Because of its forming a brown carpet on the bottom of much of the lake, especially Outlet Bay, it was referred to in our notes as the "carpet Chara." On account of its heavy incrustation of lime, this Chara presented much the same appearance the year round, looking much as if dead. In the spring it sent up little delicate green shoots from the tips of the Lake Maxinkuckee, Physical and Biological Survey 159 branches. Its presence is so universal over the lake in shallow water that details of distribution need not be given, except that it grew best in a mixture of marl and sand, and was absent from very mucky or peaty places and from gravel and pure sand, as along the east shore. According to Dr. Robinson "this is a very polymorphic form, several of our specimens representing the common American form, a few being more robust and heavily encrusted, others un- usually slender, and another form with very short whorls. Again, one specimen was peculiar in appearing, through hypertrophy of the secondary rows of cortex, to be triply corticated." 2. CHARA FOLIOLOSA Miihlenbcrg & Willdenow On the shore of Lake Maxinkuckee on the west side by Win- field's, and again extending from Long Point down to about Farrar's, there occurs in shallow water hardly a foot deep, an exceedingly handsome bushy Chara which bore fruit in such great abundance that the whole plant, upon a close inspection, had a red- dish appearance. On account of this peculiarity we named the plant the "full-fruited Chara." Perhaps a better known scientific name for this plant among collectors is Chara gymnopus A. Br. a name applied because of the absence of cortication in the lower node. According to Dr. Robinson, Braun's name is preoccupied by the name given above. The full-fruited Chara is an annual ; it grows at a depth where the water freezes to the bottom; and even if it attempted to per- sist, it would be taken out by the ice. It usually disappears before ice comes, however, probably having exhausted itself by fruiting. Various modifications or subspecies of this form, such as Chara foliolosa macilenta, and another resembling Chara foliolosa con- jugens, are to be found along the shores of Lost Lake. 3. CHARA FRAGILIS Desv. This is the identification of a specimen obtained from Long Point near Scovell's. We have no record of its distribution but it does not appear to be abundant, and is usually dredged up with various lake weeds. It bears a considerable resemblance to the common carpet Chara of the lake, C. contraria, but is a more grace- ful plant, having longer leaves and a more slender habit. 4. CHARA VULGARIS Linnaeus Represented in our collection by numerous examples. Found growing in water from 2 to 64 feet deep. Inasmuch as we were unfamiliar with the various species of Chara at the time our col- lections were made, we have no details of its distribution. 160 Lake Maxinkuckee, Physical and Biological Survey 5. CHARA GYMNOPITYS A. Braun Common on the large quaking bog surrounding the north end of Lost Lake, growing almost out of the water. Rare in Lake Max- inkuckee, two examples being found near shore in the region of the green boathouse by Norris Inlet in the autumn of 1900. This species is heavily branched, and is exceedingly soft and fine, of a delicate, bright green color. It fruits heavily, and is an annual, generally disappearing before frost. 6. CHARA SUBVERRUCOSA A. Braun Occasional in the lake, represented in the collection by several specimens. Dr. Robinson says of these : "A majority of the plants appear dioecious, antheridia being very rarely found, but they are present in a number of cases." 7. NITELLA TENUISSIMA (Dosv.) An exceedingly dainty little Nitella growing in shallow water (1-3 feet) along shore in the neighborhood of Farrar's. The whole plant grows in rather dense tufts about 25 mm. in diameter. Color dark green; rhizoids not conspicuous, main stems many, exceed- ingly slender, internodes hardly more than 2 mm. long. Leaves in whorls making a dense, globular mass at each node, so that the plant looks a good deal like large Rivularia spheres attached to a slender stalk. These spheroids of leaves, or whorls, are larger and closer together toward the apex of the plants. 8. NITELLA BATRACHOSPERMA (Reichenbach) One specimen from Lost Lake. Dr. Robinson says of it: "No. 1576 (578) agrees well both with the description and with named material in the Allen collection of Nitella batrachosperma (Reichb.) except that no trace can be seen of mucus in which the fertile verticils in that species are usually contained. Possibly therefore it may be N. tenuissima Kuetzing which is very similar, but the former alternative is greatly preferable." 9. NITELLA MUCRONATA A. Braun A delicate species growing in the muddy bottom of Lost Lake. One of the most attractive species of the region. Abundant at Bass Lake. 10. NITELLA MONODACTYLA A. Braun Reported from two specimens. We have no record of its dis- tribution. Lake Maxinkuckee, Physical and Biological Survey 161 THE DIATOMS, ETC. One of the first things to strike the attention of any one inter- ested in the flora of the lake, especially if he happen to visit it during the cooler season of the year, is the great abundance and variety of diatoms. The collector of the filamentous algae, such as Cladophora or Spirogyra or of the various Charaeese, will find his catches overgrown with diatoms, and one of our earliest botanical notes concering the botany of the lake was, 'The charas of Lost Lake are thickly covered with brown, boat-shaped diatoms." In the autumn of 1901 it was noted that the bottom of Aubeenaubee Creek was covered with a brown diatomaceous scum. The diatoms prefer cold water and in the winter they thrive luxuriantly in the lake, forming a thick, gelatinous coating over the weeds. During the summer, floating diatoms are not especially abund- ant in the lake, and do not form a conspicuous part of plankton obtained by surface-towing, this being composed mostly of blue- green algse, or entomostraca, or both. During the colder portions of the year, in early spring and late autumn, that is in early April and late September, the free floating diatoms are much more abund- ant, largely taking the place of the blue-green algse. On some days the towing in deep water would be chiefly entomostracan, re- sembling a soft, jelly mass, on other days they would consist chiefly of diatoms, and would have a harsh feeling and bristly appearance. For example, a haul of April 29 was nearly all diatomaceous. During the autumn of 1906, after towing all Au- gust, September and October, and getting little vegetable plankton but blue-green algse, a haul on November 12 contained an abund- ance of diatoms. It is unfortunate that plankton was not taken by means of a pump or other device, during the winter ; the probabil- ities are that the plant-plankton would have been almost all or entirely diatomaceous. The various diatom gatherings were submitted to Dr. Albert Mann of the U. S. Department of Agriculture for his identification. The following are his notes : "Sample No. 1. [Cladophora glomerata growing on submerged rocks, November 17, 1904] . Cocconeis pediculus E ; Gomphonema olivaceum E ; Cymbella cymbiformis E ; Cymbella maculata Kuetz- ing; Cymbella naviculiformis Auerwald (variety) ; Cymatopleura elliptica W. S., Cymatopleura solea W. S., Epithemia argus Kuetz- ing; Epithemia gibba Kuetzing; Navicula reinhardti Grun; Navi- cula gastrum Ehrenberg; Synedra obtusa W. S., Synedra radians W. S. (variety). 11— 17618— Vol. 2 162 Lake Maxinkuckee, Physical and Biological Survey This gathering is very rich in two species, both rather uncom- mon, the oval Cocconeis pediculus E., and the minute club-shaped Gomphonema olivaceum E. Sample No. 2. [Cladophora glomerata with sponges, Depot grounds, November 22, 1904]. Cocconeis pediculus E.; Gompho- nema olivaceum E.; Gomphonema constrictum E.; Cymbella macu- lata Kuetzing; Epithemia argus Kuetzing; Epithemia gibba Kuetz- ing; Epithemia zebra Kuetzing; Cymatopleura solea W. S., Navi- cula gastrum E. ; Synedra obtusa W. S., Synedra radians W. S. Similar to sample No. 1, but inferior in richness of the 2 species there named. Sample No. 3. (Spirogyra, Outlet Bay, October 29, 1904). Amphora ovalis Kuetzing ; Cymbella cymbiformis E. ; Epithemia gibba Kuetzing; Cocconeis pediculus E.; Gomphonema constrictum E.; Melosira varians Ag. ; Fragilaria mutabilis (W. S.) ; Navicula gastrum E. ; Synedra obtusa W. S. ; Synedra radians W. S. Though this gathering contained species common to Nos. 1 and 2, it is quite different in composition, being particularly rich in species of Cymbella, Epithemia and Synedra. Nos. 4, 5, and 6, unimportant as to contents of diatoms. No. 4. Spirogyra, Depot grounds, November 22, 1904. No. 5. Plank- ton haul No. 22 along shore off the Gravelpit, April 10, 1901. No. 6. Fine algaB near ice-houses, November 28, 1904.) No. 7. (Blue-green algal mass, for diatoms, near ice-houses, November 28, 1904.) Amphora ovalis Kuetzing; Cocconeis pedi- culus E. ; Cymbella cymbiformis E.; Cymbella maculata Kuetzing; Cymatopleura solea W. S.; Epithemia gibba Kuetzing; Epithemia zebra Kuetzing; Gomphonema constrictum E.; Gomphonema oli- vaceum E. ; Gomphonema acuminatum E. ; Fragilaria mutabilis (W. S.) ; Melosira varians Ag. ; Navicula rhynchocephala Kuetzing; Navicula gastrum E. ; Synedra obtusa W. S. ; Synedra radians W. 5. The diatoms make up a considerable per cent of this gathering." These identifications along with the descriptions of the condi- tions under which the diatoms were obtained, give a pretty clear notion as to their occurrence in the lake. It will be noted that the above collections consist wholly of shore gatherings, and are composed largely of species which are usually attached to other algse. The diatom taken most abundantly in the plankton hauls was a species of Asterionella. A few brief notes concerning the more striking or characteristic forms may prove of interest : 1. CYMATOPLEURA ELLIPTICA (Breb.) This large, handsome diatom was only occasionally encountered, chiefly in gatherings from Lost Lake. Lake Maxinkuckee, Physical and Biological Survey 163 2. CYMATOPLEURA SOLEA (Breb.) Occasionally scattered through gatherings near shore. 3. EPHITHEMIA GIBBA Kuetz. Fairly common, mixed in with other diatoms ; an occasional ele- ment in mussel food. 4. EPITHEMIA ARGUS (Ehrenb.) Found in the same conditions as the preceding. 5. EPITHEMIA ZEBRA (Ehrenb.) Presence simply noted. No notes. 6. AMPHORA OVALIS Kuetz. Presence simply noted. 7. CYMBELLA CYMBIFORMIS Ehrenb. One of the most common forms in shore gathering. 8. CYMBELLA MACULATA Kuetz. 9. CYMBELLA PROSTRATA (Berk.) The shallow water near the ice-houses where the chutes up which the ice is taken enter the lake, was remarkably rich in fine brown, short filamentous tufts which covered the submerged stones and timbers at that place. The material collected here proved to be especially rich in the jelly-like filaments of this species which, while not wholly absent from other parts of the lake, appeared to be nowhere else so abundant as here. The above list mentions only the most frequently encountered species or those noteworthy for some particular reason, and is only a beginning of what might be done at or about the lake by one's devoting more than only occasional or rare attention to this special subject. 10. CYMBELLA NAVICULIFORMIS Auersw. 11. RHOICOSPHENIA CURVATA (Kuetz.) Occasional, attached to fixed algse such as Cladophora, etc. A wedge-shaped diatom closely resembling species of Gomphonema, but somewhat curved. 12. GOMPHONEMA CONSTRICTUM Ehrenb. This, along with two other species, was common along shore in shallow water, particularly near the ice-houses. They are easily recognized by their wedge-shaped frustules, and all are similar in habit, being attached by a slender gelatinous stipe which proceeds from the acute end to other algse such as Cladophora, and even growing in bunches on rocks. Occasionally they separate from the stalk and are free-floating. Lake Maxinkuckee, Physical and Biological Survey 13. GOMPHONEMA OLIVACEUM Ehrenb. 14. NAVICULA REINHARDTII Griin. 15. NAVICULA GASTRUM E. Naviculas of numerous undetermined species were present in considerable abundance in the food of the mussels of the lakes. 16. COCCONEIS PEDICULUS Ehrenb. One of the most abundant diatoms of the lake, frequently cover- ing filaments of Cladophora and Spirogyra like an incrustation, being closely attached to the filament by one side. Its habit and appearance, suggesting a nit or louse attached to a hair, makes its specific name highly appropriate. 17. ASTERIONELLA so. A species of Asterionella, probably formosa Hass, was exceed- ingly abundant throughout the lake in the early spring and again in late autumn after the water had cooled. It was found not only near shore but it extended out to the center of the lake. On some days it formed the main bulk of surface towings. The col- onies of frustules arranged like the spokes of a wheel are striking objects under the microscope. 18. SYNEDRA RADIANS W. Sm. Rather common in gatherings along shore. 19. SYNEDRA LONGISSIMA W. Sm. 20. SYNEDRA OBTUSA W. Sm. Besides being frequent in gatherings along shore, various spe- cies of Synedra, some of them elongate, rather needle-like objects, were frequent in mussel food. 21. MELOSIRA VARIANS Ag. This is a very common diatom in the lake and is obtained both in plankton hauls and in hand-gatherings along shore. According to Apstein (Siisswasserplankton, p. 140) this species furnishes food for various entomostraca (Chydorus, Daphnia, and Diap- tomus). The Melosiras are especially interesting as they form the nearest approach among diatoms to the form of ordinary filamentous alg