^. IMAGE EVALUATION' TEST TARGET (MT-3) // // ^ '^ 1.0 I.I ■^ lii^ 12.2 - lis ill M 1.8 [•25 1.4 |!i.6 h* 6" ► Photographic Sciences Corporation ur □ Bound with other material/ Reli6 avec d'autres documents D D D Tight binding may cause shadows or distortion along interior margin/ La reliure serr^e peut causer de I'ombre ou de la distortion le long de la marge intdrieure Blank leaves added during restoration may appear within the text. Whenever possible, these have been omitted from filming/ II se peut que certaines pages blanches ajouties lors dune restauration apparaissent dans le texte, mais, lorsque cela ^tait possible, ces pages n'ont pas dt6 fiimdes. Additional comments:/ Commentaires suppl6ment»ires: L'Institut a microfilm^ le meilleur exemplaire qu'il lui a et6 possible de se procurer. 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Tous les autras exemplaires originaux sont filmds en commengant par la premidre page qui comporte une empreinte d'impression ou d'illustration et en terminant par la dernidre page qui comporte une telle empreinte. Un des symboles suivants apparaitra sur la dernidre image de cheque microfiche, selon le cas: le symbole — ► signifie "A SUIVRE", le symk)ole V signifie "FIN". Les cartes, planches, tableaux, etc., peuvent dtre filrr^s d des taux de reduction diffdrents. Lorsque le document est trop grand pour dtre reproduit en un seul cliche, il est film6 d partir de Tangle supdrieur gaixhe, de gauche d droite, et de haut en bas, en prenant le nombre d'images niicessaire. Les diagrammes suivants illustrent la m^thode. rata > elure. J I2X 1 2 3 1 2 3 4 5 6 1 DEPARTMENT OF THE INTERIOR. REPORT UNITED STATES GEOLOGICAL SURVEY ov THE TERRITORIES UNITED STATES CfEOLOGIST-IN-CH A ROl VOLUME XII. WASIIINGTOH: GOVKUNMENT PUINTINQ Ol'TICE. 1879. LETTER TO THE SECRETARY. Office United States Geological and Geogkapiiical Survey of the TEunrroRiES, Washinfjton, D. C, Januanj 1, 1879. SiK : I have the honor to transmit herewitli, for your approval and for publication, Volume XII of the Final Reports of the Survey under my direction. This volume has been i:>repared by Prof Joseph Leidy, the eminent comparative anatomist and microscopist, who is well known as one of the most valued collaborators of the Survey, and the author of tho first volume of the cpiarto series of Reports, entitled " Contributions to the Extinct Ver- tebrate Fauna of the Western Territories." Professor Leidy spent the greater portion of two seasons in the West under the auspices of the Survey. During this time he made a careful ex])loration of the country about Fort Bridger, Uinta Jlountalns, and the Salt Lake Basin, in search of the materials for this memoir. The use of the microscope in all branches of natural science has become so universal that the publication of the present volume in con- nection with the Survey needs no explanation. It is intended as a guide and aid to students in this new or little-known field of observation. The facility with which these small objects for study can be obtained all around us will render the work still more timely and useful to the students of this country. There are also a number of closely allied fields of inquiry, as the Diatoms, Desmids, Infusoria, Rotifera, Entomostraca, and Aquatic insectr,, etc., which, when pursued with the same skill and devotion, will prove equally fruitful in results. The Rhizopods are the lowest and si .iplest forms of animals, mostly minute, and requiring high power of the microscope to distinguish their structure. While most of them construct shells of threat beautv and varietv, lit IV LETTER TO THE Sl^OKETAllY. their soft part consists of iij(3lly-liko substauco. This the iiuimal has the po\ver of oxton(Hn<^ in threads or Ihiger-liko proct'sscs, ^vlli(•ll are used as organs of h)Coniotion and prehension, often branching. From the nppear- ance of their temporary organt-, resend)hng roots, tlio chiss of animals has received its name of IJlii/.opoda, meaning literally root-footed. In compensation for the smallness of these creatures, they make up in nuiiil);rs, and it is iiuestionable whether any other class of animals exceeds them in importance in the <'conomy of miture. Geological evidence shows that they were the starting-point of animal life in time, and their agency in rock-mid1 ▼tt TABLE OF CONTENTS. TlHo of V.ilunic XU '>f (ho riiinl 1{i'|.oi(.h I-i'ltcr to till' Si'm'tiirr Tilli' (if I'lcsli-wiitiT lihizoixxls lii'tlrr of 'I'm iisinit till , 'I'lilili' cif C'oiitints lilt rodi let iim OcMii.il KriiiiirlisdU Ihn IJIiizopmlM ricili-watcr UIiizoiMKiii l'n)ti(|iliiMlii l'i<)l(i|)!;i»t;i I.oliosii Aiiin^li:i Aincobii inodiis vcvnicdsii ... Villi iosn villdMl Oiiriiniii.liii Oiiriiiiiu'liii viiiiix ImiIiiIIi'iiiuIii Pl'ldlllVXll IVloiiiyxii villosa Diiiiiiiiipliii niiiiUMii'lia iiiiiiiliilis. llVilldiliscU-i llyiilodiiiciis riiliicniiiliis Dii;iii;;i;i Uii;iii liyi-ilbniiis iirccoliici . rriili'iii iU'llMlillillit Idlnisldinii. illTlllll roriiMii . .. . const i-U^I IV spiiiili.s ... Tngi-. 1 iii V vii ix 1 ■I c:i :;() :;o f;:i r.8 (!•,' (ill HI i)| lOci 109 iia no 117 l!!0 1>'1 1;;8 Ilyalosivtici Myaliwiiliciiia (■micalji imjiilid lilK^tll -, i'!c,';aim Qiiiiilnila (^ladnila Hvniwii'trica ... . Nobola _ 1^- l:!l l:;.s IVJ IV'i'lit'lii collariti. li 115 X TAIU-K t)F CONTKNTS. NrlM'lii — Coutl'iiU'd. Nfbelii tlnlu'lliiu.m l.Vi I'iUi-.iiitii 154 UippiHTi'pis 1")(; aiisativ VS Imrbata .- iri) i-amlatT KiO lli'U'opi'ia 100 III Icopcra ]>ii la loO |uli'ii,ia hi'i Aiivlla lo(5 Anella vulyinns 170 (lisi'oi.h's 17;t mil rata 175 ilouiata 177 artocroa 17!< CiMifroiivNis It-'O (I'lilrnii.vxis ai'iiloata It'O ('oi'lilii)i>i>(liiiiii 1~4 Coi'liliopiuliiim liiUiiiIiosiim lL-4 vt'stidim 1H6 rrotoplasta I'ildsa IW) raiiipliafjus 1!10 ^alnplla.ull^ imnaliilis l',)l liyalJinis H14 iiirvns 1!V) aviiliis VMi IVMil.xlilllu-ia 1!»7 rsoiiiloililllujjia praoilis KS Cyplunlciia i!(>l C'yphodfi'ia ampulla 'Mi Cainpasi'iis '^(M Cainpasciis ooriiuliis M:^ Kujilyplia '.'(Ki Kugly)iha alwolata '.'(7 liliata yi 1 ciistati 'Jlt^ uiiu rimata 'JID biai'hiata 'J'iO I'laiocisfu t!S: riacoi'ista spiiiosa C-1 Assiilina 'ii\ Assulina somiiiulinu 205 Triiu'iua V~(> Tii!i-.;m clichrlys 'J'JtS Sphomxl.ria i^'J Splu'iuMli'iia lent a -"..> iiiai'iolopm - '2'.'i H.li../iia si:t:f Aot iiuii>lii'v.'* ~''l Act mophrys sol ~;(5 pitta 'JU lI.t.'ropliryM... -MO lli'ti'ropluy.s myi'iapiMla UJ'.! liai>liiilii>plii'y:i »4H liai)Ui>liopiiry9 viriJis «4H I'li'gaus -50 TABliK OF COXTKNTS. Zl Page. Vnmpyri'lln '"'•' Viiiupyri'llu lutt'iititt. '-J^' liiplolihi-.VM '-^'■'O Uiploiilirvs airlH'vi «5*' Ac'diiosplm'rimii '-^^ .\('tiiio.s|iliiniiniu oichhoviiii '-Kif* Ai-:uillioi'.vtilis "<'4 Ae.mtluicvstis cliii'topliorii 2t54 ; 2(>8 f aro Hjiiloliimpo '-■''1 Ilynliiliimiio foiiostratn 'J*! rinthnilina :'*'- Cliithnilinii I'lojjnns 27S VoraniiiiilVriv 277 Oroiiiia 877 Oromiii *cm<'olii 277 Hioiiiyxii 2Sl liioiiivxii va);iiiis 281 Lists of Fii'sh-wator Ulii/.oixid.s, iiulicntiiig (ho many I'orma which oci'iir tojsi'thiT in i-rrtaiii localili.-s SS9 Concliidiu}; lioniarlvH ytH Chii'f works and civ.mnnnicationa lolatiug to the Frosh-walcr Ubizopmls, with lists dI' Iho l\>rins •h'sciibcMl, and n ,>iiitial and prolinblr rolVroni'i- nt Ihcso lo coiri'siiondinj; I'oiiiis di'si-iibcd in f ho body of tlic promvnt work v97 Index...! :W1 INTRODUCTION. The revelations of the microscope fire perhaps not exceeded in impor- tance by those of the telescope. While exciting our curiosity, our wonder and admiration, they have proved of infinite service in advancing our knowledge of things around us. The present work, founded on such revelations, I have attempted to prepare in a manner to render it easy of comprehension, with the view of promoting and encouraging a taste for microscopic investigation. Dr. Carpenter, the eminent I<]nglish physiologist and naturalist, in his treatise 'The Microscope and its Revelations', remarks that "it is a ten- dency common to all observers, and not by any means peculiar to micro- scopists, to describe what they, believe and infer, rather than what they actually witness." There are certainly peculiar difficulties in arriving at a faithful inter- pretation of microscopic observations, arising from many causes, of which a common one is the difficulty of handling minute objects, especially active living animals, so as to examine them from every point of view. While I have endeavored to describe things as they appeared to be, I am conscious of having been unable to avoid the usual proportion of errors, for which I beg indulgence, and which I leave for others who shall pursue the same path of investigation to correct. What are Rhizopods? is a question that will be asked by perhaps most persons whose attention may be directed to the present work. They are the simplest or lowest forms of animal life, constituting the first class of the Protozoa (Greek, protos, primitive ; soon, animal). I'ho Rhizopoda (Gr. rhiza, root ; pons, foot .—root-footed animals) are mostly microscopic beings, rarely just visible to the naked eye; though some are sufficiently large to appear as conspicuous objects. Their minute- ness is amply compensated by their multitude and world-wide distribution; 1 RHIZ J 2 FRESn WATER RniZOrODS OF NORTH AMERICA. essentially .iquatic, they occur wherevei" there is moisture. Commencing' from one's own doorstep, tliey niay bo found in almost every damp nook and crevice, savanna and marsh, pool and ditch, pond and lake, sea and ocean, and from the greatest depths of the latter to the snow-line of mount- ains. By far the greater proportion are marine, and their tiny shells enter abundantly into the composition of the ocean mud and abound in the sands of every ocean shore. 1 hey appear to have been the first representatives of animal life on earth; and if there is any truth in the theory of evolution, they represent our own remotest ancestors. Having existed for ages, their remains have largely contributed to the formation of the marine sediment- ary rocks. The particular Rhizopods which form the subjects of the present work are those usually designated as the 'Fresh-water Rhizopods', living mainly in comparatively still fresh waters, in the mud of bogs, among alga) and mosses, and even on the ground in damp, shaded places. My investigations were commenced foiu' years ago, and have been continued during that time, in intervals of leisure from teaching and ordinary business pursuits, until last summer, when I began the preparation of my report for publication. In the study of the Rhizopods, my attention has been more jiarticularly directed to the discovery and determination of the various forms occurring in this country, rather than to the elaboration of details of structure, habits, modes of development, and other matters pertaining to their history, though these have not been entirely neglected. In the latter respects, my researches fall short of these of some of the able naturalists of England and Germany: — Wallich, Carter, and Archer of the former, and Ilertwig and Lesser, Greeff, Cienkowski, and Schulze of the latter country. The illustrations accompanying the work, done in chromo-lithography, are not equal in execution to my desire, though they represent the charac- teristic appearance of the subjects in all cases, I believe, sufficiently vv^ell to enable the stiulent to recognize these when found. The original drawings, made by myself, I think may be fairly viewed as approximating accuracy, at least so far as relates to the outlines, which have invariably been drawn to a scale of measurements, so as to preserve the proportions of all parts. Faults in perspective and other qualities are partially due to my own w.ant of ability as an artist, and partially to the difficulty of correctly interpret- ing the views of objects as oixlinarily seen through the microscope. Many INTRODUCXrON. 3 of the illustrations exhibit various degrees of imperfection in some of the details, duo to exaggeration of defects in the original drawings, which the artists, without any knowledge of the subjects, have attempted closely to imitate. It has long been a matter of regret to me that I have not been able to secure the services of accomplished artists, educated for the special purpose to give us faithful and beautiful representations of natural-history subjects, such as we so frequently see in the scientific periodicals and other works especially of Germany and France. I think it worth while to embrace the opportunity of informing students that microscopic observations, such as those which form the basis of the present work, do not require elaborate and high-priced instruments. Such a microscope as is made by Zentmayer of Philadelphia, Beck of London, or Ilartnack of Paris, and sold at prices ranging from §50 to 8 100, ans vers all ordinary purposes. The instrument should be furnished with two objective powers, of which the higher should be at least ^tli or Jth of an inch focus. A still higher power being occasionally required, I have found an Jth or /^^th objective of great service. I have now in use a little instrument of Beck, called the Economic Microscope, with 1-inch and ^-inch object-glasses and two eye-pieces, sold by W. H. Walmsley, No. 921 Chestnut street, Philadelphia, for $50. An important addition to the instrument, for measuring, is a micrometer, divided into fractions of a millimetre, which may be purchased for a couple of dollars. I give the above statement, not with any disposition to detract from the value of the various magnificent microscopes so much in vogue, but with the object of dispelling a common impression widely prevalent, at least among those with whom I habitually come into contact, that tlie kind of work such as I now put forth can be done only with the help of elaborate and expensive instruments. In aid of my researches among the Rhizopods of the Rocky Mountain Region I acknowledge the services of my friend Dr. J. Van A Carter, for- meriy of Fort Bridger, now of Evanston, Wyoming Territory. It was not only under his hospitable roof that I was enabled to pursue my investiga- tions, but he conducted my expeditions into the Uinta Mountaii'a and other places to collect materials, and withal defrayed the expenses of our trips Dr. Carter, in his appreciation of scientific matters, has been of eminent service to geologists and other naturalists visiting his region of country. 4 FRESn- WATER UUIZOPODS OF NORTH AMERICA. Some of my most delightful recollections are associated with expe- ditions into the Uinta Mountains conducted by Judge W. A. Carter, of Ft. Bridger, or his son-in-law Dr. J. Van A. Carter. At an elevation of from eight to ten thousand feet the mountains are covered with forests, chiefly of Fir and Pine, with a most wonderful profusion of beautiful flow- ering plants beneath. The forests here and there enclose bright, grassy meadows and ponds, favorite resorts of deer, and in these I obtained rich materials for my investig.ations. Whatever may bo thought of the pertinence of publishing such works as the present one with the Reports of the Geological Survey of tlio Territories, to remove any misapprehension in the matter I deem it proper to state that my contribution has been given without pecuniary recompense. In my own judgment. Prof Hayden has acted with the most enlightened view in authorizing and encouraging such natural-history investigations as would be facilitated by explorations of the country in which his geological surveys wei*e conducted. With the exception of the cost of publi.shing the present Report, the only additional expense to which I put the Survey during my explorations in the West amounted to about $222. Much expense was saved through the liberality of various railroad compa- nies in giving me the privilege of free travel and travel on half-fare. GENERAL REMARKS ON THE RHIZOPODS. The simplest kinds of Rhizopods are unprovided with a protection or support of hard parts of any kind, possessing, at least in tlieir ordinary active condition, neither a shell nor an investing membrane. In all kinds, the soft substance of the animal mainly consists of a fluent, viscid, albumi- noid jelly, endowed with an extensile and a contractile power, by which the creature is enabled to execute all those movements which ordinarily distin- guish animal life. The motile jelly of the Rhizopod is regarded to be of the nature of the common elementary basis of organic bodies in general, and, like it, is called the protoplasm (Gr. protos, first ; plasso, I mould : — the primitive material from which organic bodies are moulded). Its resemblance in motive power to muscular tissue, or the flesh of more complex animals, led the French naturalist Dujardin, who was the first to indicate the true nature of the Rhizopods, to give it the name of sarcode (Gr. sarx, flesh; eidos, form). GENERAL REMAKKS ON TUE' KUIZOPODS. Tlie soft mass of protoplasm, or sarcode, forming the essential part of the body of all Rhizopods, has no internal cavity like the body-cavity of higher animals, neither has it a mouth like the higher Protozoa, nor has it stomach or intestine. Without trace of nerve elements, and without defi- nite, fixed organs of any kind, internal or external, the T^.hi^opod, — simplest of all animals, a mere jelly-speck, — moves about with the apparent purposes of more comjjlex creatures. It selects and swallows its appropriate food, digests it, and rejects the insoluble remains. It grows and reproduces its kind. It evolves a wonderful variety of distinctive forms, often of the utmost beauty, and, indeed, it altogether exhibits such marvelous attributes, that one is led to ask the question in what consists the superiority of ani- mals usually regarded as much higlier in the scale of life. In this relationship. Dr. Carpenter remarks of the Rhizopods, " If the views which I have expressed as to the nature and relations of their living substance be correct, that substance does not present any such differentia- tion as is necessary to constitute what is commonly understood as ' organi- zation ' even of the lowest degree and simplest kind ; so that the phj'siolo- gist has here a case in which those vital operations which he is accustomed to see carried on by an elaborate apparatus, are performed without any special instruments whatever, — a little particle of apparently homogeneous jelly changing itself into a greater variety of forms than the fabled Proteus, la)'ing hold of its food without members, swallowing it without a mouth, digesting it without a stomach, appropriating its nutritious material without absorbent vessels or a circulating system, moving from place to place with- out muscles, feeling (if it has any power to do so) without nerves, propa- gating itself without genital apparatus, — and not only tliis, but in many instances forming shelly coverings of a symmetry and complexity not sur- passed by those of any testaceous animals."* Through the motile power of the Rliizopod, it projects or extends portions of its protoplasm, which act as temporary organs of locomotion and prehension, and it again withdraws or contracts them so that they melt away in the mass and leave no trace of their previous existence. From their function, the extensions of protoplasm have received tlio appropriate name of pseudopods (Gr. pseitdos, false ; pons, foot). These a])pear, in gen- eral, in different kinds of Rhizopods, in the condition of threads of extreme 'Introduction to tho Study of the Foruniinifera. Preface, vii. 6 fim:sii-\vateu huizoi'ods of noutli aimekica. delicacy, of coarser linger -like processes, or of rounded lobes. TJioy often branch and assume a inoro or less root-like appearance, whence Diijardin gave the class the name of Kliizojiods. As previously intimated, the simplest kinds of Ithizopods are unpro- vided with hta-d parts, or even a membranous investment, and they present to the outside medium in which they live nothing but the naked mass of protoplasm of which they consist. IJy far the greater number (»f the class are protected and supported by some kind of skeleton of hard material, consisting of spicules or a trellis-work of silex, or a shell of chitinoid membrane, of linjestone, or of the former material. Mostly the hard part is intrinsic, or pertains to the inherent structure of the animal, but frequently is also more or less extrinsic. In the latter instances, the shell usually consists of siliceous particles, commonly hyaline quartz sand, diatom cases, a'ld sponge spicules. Besides some general differences in the character of the soft pai'ts, the sustaining skeleton, or protective shell, of the Khizopods, exhibits a great variety in form, construction, and ari'angement of structure ; frequently is highly intricate and often remarkable for beauty of apparent design. On the general differences observed in the soft body-mass and its pseudopods, and on the absence or presence of hard parts with their form and constitution, the ordinal and other subdivisions of the Rhizopods are founded. It however appears from the researches, especially of British authorities, such as Carpenter, Williamson, Wallich, Brady, Parker, and Jones, that the members of the class are infinitely variable, and that indeed no absohu distinctions of species and genera exist, such as appear more definitely to characterize the higher forms of animal life. My own investi- gations rather confirm this view, and, under the circumstances, we can only regard the more conspicuous and prevailing forms as so many nominal species, in likeness with the species of higher organic forms, more or less intimately related, and by intermediate foi-ms or varieties merging into one another. As is the case with all other groups of organic beings, few authorities agree in the classification of the Rhizopods ; and it is for convenience rather than from studied opinion that I have adopted the following ordinal arrangement CLiVSSlFlCATlON OF THE KlIIZOrODS. Class. RIIIZOPODA. Order I. Protoplasta ; II. Heliozoa ; III. Radiolaeia ; IV. FORAMINIFERA; V. MoNERA. The distinguished French naturalist Dujardin, who first recognized the nature of the Ehizopoda, and applied to them this name, included in the class the Foraminifera and the group of Protoplasta, excepting only the genus Aniouba, although ho fully understood the relationship of this Avith the former. The Heliozoa he viewed as another division of the Protozoa, and in his day the Padiolaria were not sufliciently known to hold a recog- nized position in zoological systems. Prof Ilaeckel, one of the latest and highest authorities on all that concerns the lowest fonn« of life, includes in the class the Foraminifera, the Heliozoa, and the Ratliolaria. The Protoplasta and the IMonora, which names originated with him, he regards as two distinct and additional classes in his proposed kingdom of Protista {protiston, primordial). Prof Carpenter includes all the ordinal groups above indicated as Rhizopoda, but associates the Heliozoa in the order of Radiolaria. Dr. Wallich* divides the class into three orders: the Ilerpnemata, the Protodermata, and the Proteina. In the first are included the Gromida, Foraminifera, and Polycystina; in the second, the Thalassicollida; and Acanthometrina ; and in the third, or highest order, the Actinophryna, Lagynidtc, and Amoebina. Pi'of. Huxley drops the name of Rhizopoda altogether, and distributes the groups into two divisions of the Protozoa : the Monora and the Endo- jjlastica To the former he refers the Monera of Ilaeckel and the Fora- minifera ; to the latter ho refers the Radiolaria, including the Heliozoa, the Protoplasta, the Gregarinida;, the Catallacta, and the Infusoria. The essen- tial character of the Monera, according to Ilaeckel, the founder of the order, is the absence of a nucleus, but this has recently been shown by Ilertwig and Schulze to exist in the Foraminifera. Carter, Greeff, and others, speak of the Heliozoa as fresh-water Radiolaria. Ilertwig and Lesser, who gave the name of Heliozoa to the ordinal group, regard them as of a distinct class fi'om the Radiolaria, and, excluding these, they associate the former together * AuiiuIb and Maguzino of Natural History, 180:i, si, p. 438. 8 rKK8U WATKIi UIIIZOI'ODS OF NOKTII AMKUICA. with tlio Foraniiniferu, Protoplasta, niul Moiicni, as lihiKopoila, but propose for this chisH to substitiuo the naiiic of Sarcodiiia. In my studios of tlio Protozoa, or animals of tho lowest siibkingdom, I have habitually viewed as Hhizopods the live ordinal groups indicated in tho above classification. This accords with the views of Prof F. K. Sdndzc, an able investigator of tho class. In a recent number of the Arehiv fiir Mikroscopischo Anatomic for 1877, \). 21, ho remarks, that his researches led him to consider as pertaining to tho Khizopods, as an essentially harmonious whole, all those low forms which, during the greater part of their life, and especially during the period of their highest perfec- tion, hold intercourse with tho exterior world, move about, and obtain food, by moiins of extensile processes of tho viscid body-substance, which are again capable of flowing back completely into tho hatter. The first two orders of the Khizopods — the Protoplastaandthelleliozoa — are those wliich are connnonly designated as tho 'Fresh-water Rhizopods'; the Radiolaria and the Foraminifora, with part of the Monera, are marine. Fresh-water lihizopods are to be found almost everywhere in positions kept continuously damp or wet, and not too much shaded. They are especially frequent and abundant in comparatively quiet waters; clear, and neither too cold, nor too much heated by the sun, such as lakes, ponds, ditches, and pools. They are also frequent in wet bogs and savannas, among mosses, in springy places, on dripping rocks, the vicinity of water- falls, springs, and fountains, and in marshes, wherever the ground is suffi- ciently damp or moist to promote the growth of algae They are also to be found in damp shaded places, among alga?, liverworts and mosses, about the roots of sedges, rushes and grasses, or those of shrubs and trees grow- ing in or at tho borders of bogs and ponds or along ditches and sluggish watercourses. They are likewise to be found with algae in damp shaded positions in tho depressions and fissures of rocks, in the mouths of cfives, among decaying logs, among mosses and lichens, on the bai'k of growing trees, and even in the crevices of walls and pavements about old dwellings and in cities. The fiivorite habitation of many kinds of Rhizopods is the light super- ficial ooze at the bottom of still waters, where they live in association with diatoms, desmids, and other minute alga^, which form the chief food of most of these little creatures. They never penetrate into the deeper and PLACKS VVUKUK UJIIZOI'ODH MAY li\i FOUND. 9 UHually bliic'k imul, which Indood is iiluiost uiiivorsuUy devoid of Ut'e of nny kind. Rhizopods 'also occur in tho flocculent nmtorials and slimy niuttor adherent to most submerged objects, such as rocks, tho dead bouj^hs of trees, and the stems and loaves of aquatic plants. A frequent position is the under side of floating leaves, such as tho.se of the Pond-lily, Nymphcca odorata: the Spatter-dock, Niiphar advena; and tho N-elunibo, Nclumblum lutetim. Certain kinds of Khizopods, especially the Ileliozoa, or Sun-ani- malcules, are most frequent among floating plants, such as Duck meat, Lcmna; Ilornwort, Ccratophyllum ; Bladderwort, Utrkuhtria ; and the vai'ious Confervas, as Zygncma, Spirogyra, Oscillatoria, and the Water-purse, Hydrodidyon. In no other position have I found Rhizopods of the kind under con- sideration in such profusion, number, and beauty of form as in sphagnous bogs, living in the moist or wet Bog-moss, or Spliaynxm. Sometimes I have found this particular moss actually to swarm with multitudes of these creatures of the most extraordinary kinds and in the most highly developed condition. A drop of water squeezed from a little pinch of 13og-moss has often yielded scores of half a dozen genera and a greater number of species. Frequently, however, the Sphagnum of many localities contains compara- tively few Rhizopods, though I have rarely found them entirely absent from this moss. Other mosses and liverworts I have not observed to bo specially favorite habitations of tho Rhizopods, not even such aquatic kinds as the Fontinalis. Notwithstanding the experience of four years' exploration aud obser- vation, I have not been able to determine the exact conditions luider which particular Rhizopods are to be obtained with certain iy and in any consid- erable numbers. In general, they are to be found in greatest number and variety under the peculiar conditions favorable to them, in old established ponds, bogs, etc., which are not liable to become completely drief' tp in t!io summer season. At times, however, I have found a profusion of one or two forms in some localities, in which, in another season, I could find but few or none. Sometimes I have found many individuals of a particular kind in a shallow pond of recent origin, which, after drying up in the summer and being renewed tho following spring, yielded no more of the same. Sometimes the most unpromising places have produced an unex- 10 FRESn WATKR RUIZOPODS OF NOUTH AMKUICA. poctod and oconsloimlly a Hiirpriuing'ly rich supply of Rhizopods, iiiul ropoiitedly tlio most promising pliices have yioldod oxcecdiiig'.y lew. The Uliizopods may bo t'ouiul at all temporato HoaHoriH (»t t!:o year; and ovon in winter, when out of tho influonco of a freezing cold, a few may bo discovered, though mostly in a comjjaratively inactive state. Frost or :i freezing temperature ajjpears to destroy them. They do not live among actively decaying vegetal matter, nor aro thoy to be found in foul water. I have further not been able to discover them in brackish waters on the sea-coast, though I detected a f(!W forms in feebly saline or alkaline waters in the Uridger Valley of Wyoming Territory. Tho Fresh-water Rhizopods appear to iiduibit indiscriminately almost any kind of country, no matter what may bo its rocky constitution, except it bo limestone. According to my experience, they aro comparatively rare in limestone districts, and I have repeatedly been disappointed in my expectation of finding them in some large limestone s{)rings in which grew a profusion of Anacharis, Chara, and other acpuitic plants. This has appeared the more surprising when it is considered ihat the allied marine order, the Foraminifera, have so largely contributed to the formation of tho limestone rocks. Tho mode I have habitually adopted for collecting Rhizopods, which is also equally well adapted for collecting manj other microscopic organ- isms, plants, and animals, is as follows : For ponds, ditches, or other waters, I uso a small tin ladle, or dipper, such as is commonly employed for domestic purposes I*ito the handle I insert a stisk of convenient length, and for this I usually carry with mo a jointed pole of two or three pieces, each about five feet. The dipper is used by slowly skimming the edge along tho bottom of the water so as to take up only tho most supei"ficial portion of the ooze, which is then gently raised from the water and transferred to a glass jar. A small hole in the bottom of the ladle favors the retention of tho collected material, but care should be taken that it is not so largo as to permit the material to stream through. After the collecting-jar is full, if more of tho material is wanted, after allowing that in the bottle to settle, I pour off a portion of the water and supply an additional quantity from the locality. Usually, I have proved more successful in obtaining Rhizopods from tho ooze near ♦^lio shores of lakes and ponds than I have in deeper water; ) I COLLKCTION AND EXAMINATION OF UlllZOPODS. 11 but this 1 BiiHpect wiih inainly duo to tho cinuuiHtiuu'o tliat ncnr tlio hIioio I could see tho oozo at the bottom of tho wator, and couhl much bettor manago to collect tho dosirod niatorial. Aquatic plants, if rooted in tho mud, should bo carefully cut off and gently lifted from tho water so as to disturb as little as possible tho adherent materials. A suflicient (puintity being placed in a tin ])reserving- can or other vessel, water from other portit)ns of the plants may bo squeezed upon that which is retained. Wet S})hagnum may bo collected and put in tin preserving-cans, and tho wator of other portions may bo squeezed upon the portion preserved. Tho same process may bo pursued with other mosses. From tho surface of the ground in wet places, to coMect the lihizopods, it is sufficient to scrape up, with tho broad blade of a knife, the grcju algous material with which the animals are usually associated. The materials collected from waters 1 have preserved, for convenient examination from time to time, by putting them in dishes about three inches in depth, filling them with fresh water, and placing them in tho window where they obtain an abundance of light, but without receiving tho direct rays of the sun. If exposed to the sun, tho water becomes unduly heated, and all living things speedily die and decompose. Care should also be observed not to have too nuich material in tho same dish ; and I have found it best to i)reserva a stratum of ooze which, when settled, is no^ more than from a line to the eighth of an inch in depth. Some Duck-meat, Leiiiiia, Bladderwort, U(rictilaria, Spirogyra, or other })lant, collected, and placed iu the water, greatly promotes its freshness and continued purity. The dishes should bo covered with panes of glass to exclude tho dust and prevent evaporation. A day or two after tho materials have been placed in dishes, the sediment has deposited and tho water become clear. In this condition, there msiy usually bo observed on the surface of tho sediment a continuous thin film, or patclies of a yellowish, yellowish-green, or green color. The film, or patches of the same material, is more tenacious than the dejjosit beneath, and consists of the various living organisms, especially diatoms, dosmids, rhizopods, etc., which have extricated themselves from the oozo to occujjy tho most fiivorablo position to continue their functions. Indeed, it is a remarkable phenomenon to observe with what ease and rapidity these extremely minute living creatures can free themselves from tho depths of 12 hM{b:8ll WATER KIlIZOrODS OF NORTH AMERICA. tho nuul in which thoy had been buried, to ocoiipy a position on its surtai'o, where thoy receive the full benefit of the conditions necessary to their life. F:om tho living; lihn, as it niijjht not inappropriately be called, the desired objects for exaniinatittn are to be obtained. Portions may be lifted with a ylass tube closed at the uj>per end by the finjjer, antl then with the other end brou<>ht into contact oze into the tube, when, the ling'T beinj;; replaced, ;\ drop of tho contents of the tube niav be trai'.sferred to a sjlass slide or an aninjalcnla cayo for the iielil of tho microscope. The materials collected and disposed of in the manner above described ni;>\ be preserved in a good condition for examination for weeks together, and indeed without any further care in this way 1 liave kept a stock of l\hizopods alive during the winter. 'I'he Khizopods collected with wet Sphagnum, or otlier mosses, or on damj) earth, may be readily kept in good comlitioi". for examination in glass cases, for which purpose common wide-mouthed candy -jars answer. They should be kept in the light in the same manner as tho dishes of water. With Sphagnum 1 have retained its peculiar lilnzopods alivi> tho whole year through. To exanune the T{hizoi)ods of Sphagnun\ or other nuisses. or from tho algous tihn of damp places, wet a fragment, teaze it with a knif" and iorceps, and press the water from the pnlpy mass into a watch-crystal. A drop of tho sediment collected is then to be transferred to tho Jield of tho microscope. The diiVerent forms oi fresh-water Khizopods are not generally restricted to dift'ereut locr.'ities or positions, but are connnoidy found mori> or less in association together. I'sually the naked forms, and especially the larger ones, the Oitllugias and the Arcellas, are found most frequently, abimdautly and bi«st c'eveloped, in the ooze of bodies of water. The Euglyplias, Nebelas, and their nearer allies, are in like manner nu>st freipunit in tho moist Sphagnum of bogs; ami the lloliozoa in the positions previously indicated. Tho chief localities from which 1 have myself collected the materials of tho present work are as follows : i^L. DHOKHS OK HHlZOl'Ona— U.VniOLAHIA. 13 Ponds, sj)ni)<>:s, and niarslios in tho vioinity of riiihidolpliia, l)ut espe- olnlly tho diti'hos wliioh travorso tho ^nwt nioadowa bolow tho city, in tho alhivial trian<;lo caUod tho Nock, botwoon tho Dolawaro l{ivor and tho month of tho Sclmylkill liivor. l\)nds, niarshoa, etc , ah>nj>; tho i-ourso of tho Dohiwaro Rivor, botli in IVnnsylvania and Now Jorsoy, in \n I'hihidolphia to tho Dohiwaro Wutor Gap. Sphagnons btiys, pools, and }H>nds on tho Pokono Mountain, Monroo County, and on Ihoad ^[ountain, Schuylkill County, Ponnsylvania Tho lower jiart of tho Stato of Now Jovsoy, alon May Kailwav. 'rhrou<>hout this bro.ul rojj-ion materials were col- looted from many localities; ponds and pools, s{)ha<;nous bo<;s, cedar swamps, savannas, and cranberry liuids. Also Lake llattacawana, or Pudd's Lake, on Schoolov's Mountain, Morris County, New ilersoy. The vicinity of Noank, on tho coast of Connecticut, and of Newport, Rhode Island. Pridgor Valley, in tho southwestern ctn-niu- of Wyon\ing Territory, and the Uinta Mountains to the height of 10,()()0 foot, in tho same region. Partridge Island, at tho head of the Pay of Fundy, Nova Scotia. Poforo entering in detail upon tho s|)ecial snbjocts of my studios, tho Fresh-water Rhizopods, nearly all of which ])ertain to the orders of the )'rotoplasta ard tho llelio/.oa, some remarks on tho characters of the 'chor orders o( tho class may not bo out of place. Tho Kadiolaria {radiolu-s, a little ray) are tho subjects of an ela- borate and magniricont work by Dr. Frnst llaeekil, Professor of Natural History, in Jena.* They are exclusively marine Rhizopods, couiitrising many wonderfully beautiful forms, living and swinuning in vast nudtitudes in tho superficial waters of tho ocean. They are generally minute, and aro tho most complex in their constitution of any of tho Rhizopods. They aro commonly furnished with a siliceous or ilinty skeleton, which, in variety of tbrm, svminetry, and intricacy of construction, is a marvel of beauty. Tho matc.'iul of tho skeleton is derived from tho exceedingly small proportion ' I>ii> KiiilioiiiriiMi (Ifliiziiinulii KiulinliiiiiO, Iti'rlln, tSiW. N i^ i| 14 FREf»n WATER RBIZOPODS OF NOKTH AMERICA of silex contained in the sea-wuter. After deatli, the skeletons of the Radio- haria sink to the bottom of tlio ocoan, where they accumulate as an abun- dant component of the mud. In the island of Barbadoes, extensive rock strata of the Tertiary period, 1100 feet in thickness, consisting of marls, tripoli, and ferruginous sand- stones, are largely composed of the siliceous skeletons of Radiolaria. Material from these strata called ' Barbadoes earth' is well known to microscopists, and is highly prized for the perfection and beauty of the forms it supplies. Likewise, in the Nicobar Islands, of the Indian Archi- pelago, the solid nucleus of the islands, consisting of cliiys, marls and arenaceous marls of Tertiary age, 20J0 feet in thickness, is largely com- posed o\' the remains of Radiolaria. According' to Haeckel, the soft body of the Radiolaria is more highly organized tluni that of the Foraminifera and Heliozoa. It contains a cen- tral capsule of firm membrane enclosing masses of minute colls. The exterior protoplasm commonly contains numerous yellow cells enclosing starch-grains, and in some forms also large vacuoles, and from it emanate in all directions countless pseudopodal rays. Most Radiolaria possess a highly complex skeleton composed of silex, exhibiting in different kinds a wonderful variety of the strangest and most elegant forms. Sometimes it consists of a simple trellised ball, some- times a series of several such Vails enclosed concentrically in one another, and connected together by radial bars. Gencrall}" delicate spines, often branching, radiate from the surface of the balls. In other instances, the skeleton consists of a star mostly composed of twenty spines, arranged in definite order and united in a common centre. In some Radiolaria, the skeleton is a delicate, many-chambered shell, as in the Foraminifera. Indeed, says Prof. Ilaeckel, no other group of organisms develop in the construction of their skeleton such a variety of fundamental forms, with such geometrical regularity, and such elegant architecture. The For-^minirera (foramen, an aperture; fcro, to bear) constitute by far the most important order of the Rhizopods, especially from the vast quantities in which they have existed in all times from the earliest known appearance of life on earth until now, and from the enormous extent in which their remaiiis liavo contributed to the formation of rocks. They are marine shell-bearing animals, mostly living at the bottom of oceans and ORDEKS OF RHIZOPODS— FORAMINIFEEA. 15 -# seas, some attached, bnt generally free, and creeping on the surface of sea- weeds, on the mud, the sands and rocks, or on dead shells and corals, or the lifeless fixed hard parts of other living animals, as the shells of molluskc, corals, sertularians, and sponges. Large numbers are pelagic, or live on the high seas, swimming in the superficial water, while their dead shells foi-m an incessant rain, and contribute largely to the formation of the ocean mud. Of their class, the Foraminifera have been longest and best known, -and their tiny and beautiful shells have been the subjects of many descrip- tions and illustrations. The characters of the order have been especially elaborated in more recent works, among which may be mentioned the "Organization of the Polythalamia" by Dr. Jlax S. Schultze, and the " Introduction to the Study of the Foraminifera" by Dr. William B. Cai-- penter. The Foraminifera, though generally too minute to be distinguished by tlip -^aked eye, are readily detected with a good pocket-lens. They are commonly largest in tropical seas, and even the same species are better developed in warmer than in colder latitudes. A few, the giants of their kind, are conspicuous for their size, and range even to the diameter of seve- ral inches. In former ages they frequently reached a greater growth, so that fossil forms ai'e connnonly larger than those now living. Some of the extinct species exceed in size double that of any knov/n existing ones. The Foraminifera are provided with a shell, mostly calcareous, but often partially calcareous with incorporated siliceous sand, or it is composed ot smd-grains alone cemented together. With few exceptions, the shells are partitioned into many chambers, and. the most common forms, which are spiral, so nearly resemble the shells of the Nautilus and Ammonite, that until a comparatively late period all were classed together as Polythalamia (Gr. jpo?MS, many; thalamos, chamber) or Cephalopoda (the Cuttle-fishes). D'Orbigny, recognizing in the shells of the Nautilus and Ammonite that the chambers were traversed by a tube, while in the shells of the so-called microscopic Cephalopods the chambers communicated by one or more holes, called the foraier Siphonifera {sq)1ion, a tube; fero, I carry) and the latter Foraminifera. In a systematic arrangement of the Cephalopods in 182o, D'Orbigny still retained the Foraminifera as an order. Dr. Carpenter remarks that "no suspicion appears at that time to have crossed the mind '] 16 FRESH WATER RHIZOPODS OF NORTH AMERICA. II of M. D'Orbigny tliat the place of these organisms miglit be among tlio lowest instead of among the highest of the Invertebrata." The true nature of the Foraminifera, and their relationship with Amoeba, Difflugia, and other animals of the kind, was first recognized by tiitj accurate observer M. Dujardin. In the Annalcs des Sciences Naturelles for 1835, there are two articles from M. Dujardin, entitled "New Observations on the Micro- scopic Cephalopods" and "New Observations on the pretended Micro- scopic Cephalopods". The author remarks that he has observed several genera of these animals from the Mediterranean in a living condition, nota- bly Miliola, Rotalia, etc. The segments of the shell successively augment in volume, and are occupied with a red or orange-colored animal matter, of the consistence of thick mucus, very contractile, and susceptible of length- ening into threads. In conclusion, the author remarks that "if one wishes to assign to these animals their place in the animal kingdom, in considering the absence of organs, the homogeneity and simplicity of their material — a sort of nuicua endowed with spontaneous movement and contractility — one is led to place them in the lowest rank I first designated them under the name of Symplectomcres, only having in view the succession of similar parts rolled together, in the known species ; but the observation of Gromia has led me to prefer the name Rhizopods, to express their singular mode of creeping by means of threads, which extend and branch like roots." Dr. Carpenter divides the Foraminifera into two suborders: the Imper- forata and the Perforata, founded on the circumstances that in the former the shell has mostly but a single orifice of communication with the exterior for the emission of the pseudopods, while in the latter the shell has its outer walls everywhere minutely perforated for the same purpose The sarcode of the Foraminifera consists of a viscid protoplasm, usu- ally more or less colored yellowish, brown, or red ; the color being deepest in the earlier formed chambers of the shell, and becoming less towards the last one, in which it is very feeble or absent altogether. The protoplasm contains granular matter, and vacuoles, or drops of more liquid matter than that of the general mass of the sarcode. Nuclei have commonly been sup- posed to be absent, but recent researches of Hertwig* and Schulzef have proved their existence. The pseudopods of the Foraminifera extend as 'Jenaischo Zeitscbrift, x, 1870,41. tAic'liiv f, Mikros. Aiiat. 1877,9. ORDERS or RHIZOPODS— FORAMINIFURA. 17 exceedingly delicate threads, often in large number, from the one or several mouths or numerous pores of the shell. They divide and subdivide into finer and finer threads, which inosculate freely where they come into con- tact with one anotlar, so as to produce an intricate net. From this condi- tion. Dr. Carpenter has applied to the order the name of Reticularia. The pseudopods exnibit continual changes in their arrangement, and an incessant circulation in their course. In the larger threads, two streams are observed at the same time, passing in op^wsite directions ; in the finest threads, a single stream moves outward or inward. The cun-ents carry along granules of the protoplasm, and also convey particles of food which may be caught in the way of the pseudopods. Sea-sands contain as an important constituent the d^ad shells of recent Foraminifera, though in very variable proportioi-s. They are generally most abundant in the sands of warmer latitudes, and especially on shores profusely furnished with sea-weeds. Plancus,* who, according to D'Orbigny,t was the first to describe and figure the shells of Foraminifera, counted 6000 individuals in an ounce of sand from the Adriatic. D'Orbigny estimated that there were 160,000 in a gramme of selected sand from the Antilles. Schultzef gives 1,500,000 as the number he found in fifteen grammes of sand from Gaeta on the coast of Sicily. Even on the comparatively barren shores of New Jersey, consisting of quartz sand, fora-niniferous shells occur in notable quantity. In a portion scraped from the surface between tides, at Atlantic City, I estimated that there were 18,700 shells to the ounce avoirdupois, all of a single species of Nonionina In another sample, from Cape May, I obtained 38,400 shells to the ounce, likewise of the one species. In sand collected by scraping up the long white lines on the bathing beach at Newport, Rhode Island, occupying an indenture of the rocky coast, covered with sea-weeds, foraminiferous shells were found to be much more numerous, but, excepting in the case of some examples of Miliola, of smaller size. In an ounce of the sand, I estimated that there were about 280,000 shells, of several genera and species. It would appear as if the deep-sea mud almost universally was mainly •Ariminensis do conchif* iiiinus nntm. Venicii 17;t!). ~ ~ t Foraminii^roK : Lii H»^r», L'i«l,. ,l„ Vu\m. Pui-Ib,' IBU!). Introcluctiou, vii. 1 Oigiimsmiis tl. I'olythulamieu, 1054, |i. ;<5. 2 KHIZ i \ 18 FKESn-WATER RIIIZOPODS OF NORTH AMERICA. derived from the shells of Foraniinifera. T'ao sediment of the Atlantic Ocean is so largely constituted of one kind of foraminiferous shell, the Globigerina buUoldcs, that the nmd is now frequently spoken of as the *Glo- bigerina ooze'; and this material is likewise found in the Pacific and other oceans and seas. In speaking of the composition of the ocean mud, Mr. Thomson re- marks : "The dredging at 2435 fathoms at the mouth of the Bay of Biscay gave a very fair idea of the condition of the bottom of the sea over an enormous area, as we know from many observations which have now been made, with the various sounding instruments contrived to bring up a sample of the bottom. On that occasion the dredge brought up about one and a half cwt. of calcareous mud. The matter contained in the dredge consisted mainly of a compact 'mortar', of a bluish color, passing into a thin — evidently superficial — layer, much softer and more creamy in consist- ence and of a yellowish color. Under the microscope the surface layer was found to consist chiefly of entire shells of Globigenna huUokles, large and small, and fragments of such shells mixed with a quantity of amorphous calcareous matter in fine particles, little fine sand, etc. Below the surface layer the sediment becomes gradually more compact, and a slight grey color, due probably to the decomposing organic matter, becomes more pro- nounced, while perfect shells of Globigerina almost entirely disappear, frag- ments become smaller, and calcareous mud, structureless and in a fine state of division, is in greatly preponderating proportion. "One can have no doubt, on examining this sediment, that it is formed in the main by the accumulation and disintegration of. the shells of Globi- gerina— the shells fresh, whole and living in the surface layer of the deposit, and in the lower layers dead and gradually crumbling down by the decom- position of their organic cement, and by the pressm-e of the layers above — {in animal formation in fact being formed very much in the same way as in the accumulation of vegetal matter in a peat bog, by life and growth above, and deat'.i, I'etarded decomposition and compression beneath."* When we are thus informed of the constitution of ocean mud, we are fully prepared to learn that vast rock-formations of past ages are composed of the shells of Foraniinifera. D'Orbigny observes that the ' calcaire gros- sier' of the Paris basin, a coarse limestone of Tertiary age, is chiefly com- "Tlii! DcpllLs (if 111.! Sill, I). 410. ORDERS OF RIIIZOPODS— MONERA. 19 posed of the shells of these animals. As this rock is employed for building', he remarks that it is no exaggeration to say that Paris, as well as the towns and villages of some of the surrounding departments, are almost built up of Foraminifera. The limestones of early Tertiary age of Southern Em-ope and Asia and of Northern Africa are largely constituted of Nummulites {nummulus, a small coin), — foraminiferous shells resembling money in shape, and ranging from the size of a pin-head to that of a dollar. This 'Nummulitic Lime- stone ' attains a thickness of several thousand feet, and contributes to form those great mountain chains, the Pyrenees, Alps, Apennines, Carpathians, and the Himalayas, often including their snow-clad peaks. It extends through the Mediterranean basin, Asia Minor, pnd Persia, into India. In Egypt, it furnished building-stone for the great Pyramids. The chalk of Europe, a soft limestone of an earlier time than the former, is also -chiefly composed of the shells and their decomposed i-emains of Foraminifera. The so-called green-sands, like those of our neighboring States, New Jersey and Delaware, of the same and other periods, from the earliest to the latest times, have been largely due to Foraminifera. Prof. Bailey has further shown that a similar material to the green-sand is now in process of formation in the Gulf of Mexico, through the same agency. The fossil-bearing rocks of earliest time present illustrations of the same character. Limestones of the Carboniferous age have been largely due to foraminiferous shells, and one kind has been sjiecially named 'Fasulina Limestone' from the abundance of shells it contains of the foraminiferous genus Fusulina. The group of organic beings designated as ITEonera (Gr. moneres, simple) was first definitely characterized by Prof Ilaeckel, who describes it in his Monograph as follows : Organisms without organs, which in the perfectly developed condition consist of a freely movable, naked body, composed of a completely struc- tureless and homogeneous sarcode (protoplasm). Never differentiating nuclei within the homogeneous protoplasm. IMotion occurs through con- tractions of the homogeneous body- substance, and through extension of variable processes (pseiulopods), which either remain simple, or branch and anastomose Nourishment occurs in various ways, mostly after the manner of Khizoj)ods Heproduction takes place only in aji asexual manncj' 20 FRESH WATER RHIZOPODS OF NORTH AMERICA. through division. Often, though not always, the free movi ig condition interchanges with one of rest, during which the body excretes and encloses itself in a structureless investment.* Though Prof. Haeckel has indicated and described a number of fresl:- water species of Monera, I am not sure that I have had the opportunity of finding any of them, excepting perhaps the genus Vampyrella of Cien- kowski, which he ascribes to the same order. In his History of Creation, Prof. Haeckel observes: "In a state of rest most Monera appear as small globules of slime, invisible or barely visi- ble to the naked eye, and at most about the sisse of a pin-iiead. When the Moner moves, there are produced on the surface of the little slimo ball, finger- like processes or very fine radiating threads, the so-called false feet or pseudopods. The latter are simple continuous processes of the structure- less albumen-like mass of which the body consists. We are unable to perceive difl^erent parts in it, and we can obtain direct proof of the absolute simplicity of the semi-fluid mass of albumen, for with the aid of the micro- scope we can follow the Moner as it receives its nourishment. When minute bodies suitable for food, as, for instance, small particles of decayed organic bodies or microscopic plants and infusoria, accidentally come into contact with the ^oner, they remain hanging to the sticky surface of the semi-fluid mass of slime, and here produce an irritation, which is followed by a strong afflux from the slimy mass of the body, and they become finally completely enclosed by it, or they are drawn into the body of the Moner by displacement of the several albuminous particles and there digested, beinjj absorbed by simple diff'usion (endosmosis). "Just as simple as is the nourishment, is the mode of reproduction of these primitive beings, which one cannot positively call animal or plant. All Monera propagate themselves only in an asexual manner by self- division. When such a speck, for example, a Protamoeba or a Protogenes, has attained a certain size by Ihe assimilation of foreign albuminous matter, it falls into two pieces ; there is formed a constriction around the middle, whivjh finally leads to the separation of the two halves. Each half becomes rounded, and then appears as an independent indi>'idual, which commences anew the simple play of the vital phenomena of nutrition and propagation. In other Monera {Vampyrella) the body in the process of propagation, * BiulcgUcbc Studiun, 1870, 08. ORDERS OF RHIZOPODS— CHALIiENGERIDA. n instead of two, falls into four equal parts, and in others again {Protomonas, Protomyxa, Myxastrmi) at once into a large number of small globules of slime, each of which again by simple growth becomes like the parent body."* Sir Wyville Thomson, in the Voyage of the Challenger, briefly describes certain Rhizopods, which be refers to a new order. On page 341 of the work indicated, he' says: "In the investigations with the towing-net, made by Mr. Murray during the latter part of the cruise, at all depths, about thirty species or more were procured of a beautiful group of minute forms approaching, but in many important points differing from the Radiolarians. This order have apparently hitherto escaped observation, and I retain for the type genus the name ChaUengeria, and for the Order that of 'Challengerida'. As a rule these forms are extremely minute, although some of them approach in size the smaller Radiolarians. Thoy consist usually of a single chamber of silica varying greatly in form, sometimes triangular, sometimes lenticular, and frequently globular or flask-shaped ; with a single opening usually guarded by a beautifully formed and fre- quently highly-ornamented lip. The contents of the shell consist of a mass of granular sarcode, with one or more large well defined granular nuclei, and a number of dark brown, sometimes nearly black, rounded compound granular masses. The Challengerida are essentially Rhizopods with mono- thalamous siliceous shells ; and their zoological position may be nov very far from such forms as Gromia." Nothing is said of the characters of the pseudopods ; but should they be of the same kind as those of Gromia, this, with the new forms, might conveniently be associated in the same order. • NatUrliclio Scliopfungsgesoliichto, 1872, 166. N FRESH-WATER RHIZOPODS. PROTOPLASTA. : Protos, first ; plasio, I form or mould. The Protoiilasta comprise by far the ^eater number of the Fresh- water Rhizopods, and inchide nearly all the known forms except the Ileli- ozoa, or Sun-animalcules. They are divisible into two sub-orders, the liobOMa and the Filosn, founded mainly on the difference of the pseudo- pods, which in the former are comparativel}' thick, finger-like or lobose, and in the latter filamentous and of extreme delicacy. Some of the Protoplasts are naked, usually liave no real distinction in the relative position of parts, and emit pseudopods from any portion of the body-mass, though even most of these when in movement, for the time being, may have the body more or less differentiated into an anterior and a posterior region. The greater number of the Protoplasts are provided with an exterior shell, commonly of a more or less flask- or Vase-like shape, and, with few exceptions, having a single orifice, from which the pseudopods are projected. The shell is an excreted membrane, chiti'.ioid or siliceous in character, or it is constructed of siliceous sand or particles of similar con- stitution, but, so far as known, appears never to bo composed of carbonate of lime. PROTOPLASTA LOBOSA. The liobose Protopla8tit easy to make out their exact form and constitution. They sometimes appear as octahedrons, rhombohedrons. and hexagonal tables. Auerbachf supposes them to be of a fatty nature ; Carter f describes them as octahe- drons, or modiiications of the same, and as })robably consisting of oxalate of iime; and Wallich§ speaks of them as rhombohedrons, probably of car- • l\)l>nliir Scioiico R«vi(>\v, 1877,217. t Zi'ilwliriri I', wis. /oiilogic, !,-::)(!, ;i(l!». t Aiiimls iiiul Miigii/.iiii' ol' Niitui:il IliNtnry, IHlKl, xii,;(:i. Jlliiilom, lH(i;l, xi,4;t4; xii, t:«-i. 38 FRESn- WATER RIIIZOPODS OF NORTH AMERICA. bonate of lime, and again he refers them to the hexagonal system. The crystals sometimes occur in notable quantity, even in young specimens of Amoeba, and are quite conspicuous ; at other times, even in what appear to be the same species, they are few and small, or not clearly evident. The crystals, unlike the quartz sand, appear to be an intrinsic element of the animal. There is yet little positively known in relation to the modes of repro- duction of Rhizopods, though it is certain that a common mode is by division, as has been observed in some of the naked Lobosa, Heliozoa, and Monera. The opportunities for observing the process have appeared to me to be by no means frequent ; for in all the four years of my study of the Fresh-water Rhizopods, I met with an Amceba in the state of division in but few instances, and the common Sun-animalcule, Adinophrys sol, but rarely. The shell-covered Protoplasts are frequently found in pairs, with the shells moutii to mouth. When the shells are sufficiently translucent to allow the soft parts witiiin to be seen, at times it is observed that these become confluent in one mass, which flows to and fro from one shell to the other. The mass finally dividing again into two, the individuals with their shells become separated without apparent change from the original state. This conditioii of union of a pair is commonly named 'conjugation', and lias been supi)08ed to hold a relation with the act of reproduction, though it has not been positively proved to be so. From certain appearances, hereafter to be considered in the special cases, I have suspected that many of the supposed examples of conjuga- tion are really due to reproduction through division. From the appear- ances alluded to, there is reason to suspect that from time to time the shell- covered Protoplasts, under appropriate conditions, — such as are induced by being well fed, so that the animal is in a highly active condition, and the shell is surcharged with sarcode, — quickly project one half the mass of sarcode, which as quickly assumes the shape and size of the parent. The exuded mass at the same time may be supposed to rapidly secrete a shell ; or, if this is conqjosed of foreign matters, as in the case of a Difflugin, it may be immediately formed by the adherence of particles to the exuded sarcode. Jf such shall be proved to be one of the modes of reproduction of the shell-covered Protoplasts, it is one w^hich we may suppose would PKOTOPLASTA— Tllli; LOllOSE PllOTOPLASTS. 29 •/ assure conipamtive uniformity of character in the shape, size, and consti- tution of the shell, just as buds of the same plant ordinaril}' assure the same varieties of flowers and fruit. On the other hand, reproduction of the Rhizopods from germs or spores would probably furnish a partial exi)lanation of the multitudinous varieties of form. The naked Protoplasts, as represented by species of Amojba, etc., at times which are apparently related with circumstances unfavorable to activity, even of an opposite character, as extremes of temperature, cold or he.it, assume a condition of complete quiescence, reminding one of the winter or summer sleep of higher animals. The condition is preceded by retirement into the deeper part of the ooze in which these lowly creatures live, or by concealment in dirt and other materials accumulated around and adherent to them. Contracted into a globular form, they are puiged of all remains oi food and other materials, such as sand, etc., swallowed with the former. They then become gradually invested with a structureless mem- brane consisting of one or several layers, apparently the product of exuda- tion and coagulation of a portion of the protoplasm of the sarcode mass of the body. In this encysted condition, the Protoplast remains an indeti- nite period, and perhaps usually undergoes transformation into reproductive germs or spores.' Often, however, if the circumstances are changed for one favorable to activity, the creature bursts its envelope and creeps forth to feed in the ordinary manner, as if it had been passing a time in sleep. The shell-covered Protoplasts are frequently found with the sarcode mass contracted into a ball commonly defined by a membrane of variable thickness, and apparently due to the coagulation or condensation of the ectosarc, or oi an exterior more clear and homogeneous layer of the soft structure. In the formation of these qu'.3scent balls, they are purged of all remains of the food which is often seen occupying t'le space between the ball and the mouth of the shell. Frequently, also, in the quiescent or encysted condition of the sarcode, the mouth of the shell is closed by an vtperculum apparently formed by the accunuilation of successive layers of Kiatters discharged from the sarcode bfill. The encysted ball of the siiell-covered Pi-otoplasts in many instances appears to be resolved into globules, or coarse granules of nearly luiifonn size, wJiich are probably to be viewed as germs or spores. From the researches of Mr. Carter* it would appear that in Anuijba ' AuiiiiU ttiiil Mngazinc of Natunil History, xviii, 1856, p. 1226. 30 FRESH-WATrJl RHIZOPODS OF NORTH AMERICA. \ I and Euglj'plia, x-epresentatives of tho Lobose and Filoso Protoplasts, tlio endosarc becomes resolved into nucleated cells, which are of the nature of ova, while the nucleus is resolved into graauliferous non-nucleated cells, finally breaking up into their constituent granules, which are of the nature of sperniatozoids. AM(EBA. Greek, ainoibos, cliaiiging. Voti-ox: Liiiiiieus, 1700. Chaos: LiiiuasuH, 17G7. Prolciia: MUUcr, 1786. Bory, lS-24. Amaha : Ehrenbcr};, 1831. Vibrio: Giiielin, 1788. J':,tba: Animal, when at I'est, a spherical or oval mass of soft, hyaline, color- less, homogeneous, pale granular protojjlasm, possessing extensile and con- tractile power, and in the active condition devoid of an investing membrane, or any kind of covering. In motion, mostly of exceedingly variable and ever-changing form, and with no absolute distinction of parts, though fre- quently exhibiting more or less disposition to differentiation into an anterior and a posterior region. Ectosarc hyaline, crystal-clear, but, with high mag- nifying power, exhibiting more or less of an infinitely fine granular consti- tution. Endosarc continuous with the former, finely and coarsely granuLir, mingled with corpuscles of inirinsic and varied character, together with various ingesta, consisting of food, water-drops, sand, etc. Containing also a nucleus and a contractile or pulsating vesicle, or sometimes more than one of either or both of these constituents. Body with no external appendages of a fixed or permanent character. Pseudopods digitate, simple or branching, cylindroid and blunt, or more or less tapering and pointed, or short and broadly lobato, consisting of exten- sions of the ectosarc with variable proportions of the endosarc, or of the former alone. Animal in the quiescent state, purged of food and other ingested mat- ters, globular in form, and invested with a structureless membrane, appa- rently produced by coagulation of a portion of the ectosarc. AMCEBA PllOTEUS. Plates 1, figs. 1-6; 11, ligs. l-i:i; IV, f.^s. 2-2-25; Vll.ilgs. 13-19; VIII, figs. 17-30. J)rr Idtinc I'rolciis. Rdscl: Inscctcii liclustl'iuii};, ITri.'), iii, ('i\>l, tiil>. <'i. I iilrox ('htU)n. liinniiMis: SyHtiinii Xatiiiii', fd. N, 17(ilt, i, fi-Jl. I'olrox ProleuH. PiiUiis: I'.lciiclum Zoophytoriiiii, 17(')(>, 417. Chaos I'rollicns. I.iiiiiiuiis: SjHtcniu Natiirio, ed. l!i et 13, 1707, i, 1320. Volvox Hjtliarulii. MiilUr: Veiiii. TincH. I'liiviiU. 177;t, 31. «-,' GENUS AMCEBA— AM(E1}A PllOTEUS. 31 ProleKS diffliiciw. Miillcr: Aiiiiimlonla Infusoria, 17SG, 9, tab. ii, figs. 1-12.— Sumray : Diet. Sci. Nut. 1820. Vibrio rrotcua. Gmeliii: Liu. SjHt. Nat., cd. Hi, 1788, 3899. Amiba dh-crgcna. Bory; Diet. Clas. Hist. Nat. 1822, 201. AmibaKasilt. Bory: Encyc. Mc^lh., Hist. Nat. Zooiihytcs, 1824, 46.— Dnjaidin: Hist. Nat. Zoophytes, lufus. 1841, 232. Amiha MUUcri. Bory: Encyc. JIdth., Hist. Nat. Zoophytes, 1624, 40. Amoeba princcpa. Ehrenberg: Abh. Ak. Wis. Berlin, 1831, 28, 79; Infusiousthiorchcn, 1838, 120, Taf. viii, Fig. X.— Perty: Ken'utuis-s klein.st. Lcbensformcn, 1852, 188.— Auerbaeh: Zeitsch. wisscus. Zool. 1850, 407, Taf. xxii »•'"• ' 10.— Lcidy: Pr. Ac. Nat. So. 1874, 14,143. Aviiba princeps. Dujardin: Hist. Nat. Zoophytes, Infus. 1841, U'i'i, pi. i, lig. 11. Amaba ramosa. Froiuentcl: fitudes Jlicro :oaires, 340, pi. xxviii, fic, 2. Amaba communis. Duncan: Pop. Sc. Review, 1877, 233. Anurba chaos. Leidy: Pr. Ac. Nat. Sc. 1878, 99. Amaba proleiis. Leidy: Pr. Ac. Nat. Sc. 1878, 99. S])ecies comp.iratively large, nearly colorless, or more or less black by transmitted light, pale yellowish by reflected light; spheroidal or ovoidal when at rest; very variable and ever changing in shape when in motion, ordinarily ramose, palmate, or radiate; comparatively active, creeping, with a disposition to differentiate into an anterior and a posterior region. Pseu- dopods digitate, simple or branching, and blunt, sometimes tapering and pointed. Posterior part of the body in contraction receding in the advan- cing pseudopods, sometimes assuming a mulberry-like appearance. Nucleus usually single, discoid, habitually posterior. Contractile vesicle usually single and large, habitually behind the former. Ectosarc thinly differen- tiated. Endosarc finely and coarsely granular, Avith many and varied ele- ments, contributing in its flow to the extension of the pseudopods. Size, in the globular form to 0.2 mm.; in the ovoidal form to 0.3 by 0 15 mm.; extended inadendroid form, occupyingaspaceof0.5mm.inlength by 0.4 mm. in breadth; in a palmate form 0.5 mm. long by 0.35 mm. broad; in a radiate form from 0.2 mm. to 0.5 by 0.4 mm. ; in an irregularly cylindroid form to 1 mm. long. The largest observed occupied a space of 0.6 by 0.2 and 0.35 mm. ■ ioca^%.- -Common in the superficial ooze of ponds and ditches almost everywhere, though rarely in large numbers. Ditches below Philadelphia and brick-ponds in the vicinity. Ponds in the neighboring counties, including Delaware, Chester, Montgomery, Bucks, Berks, and Northamp- ton; Broad Mountain, Schuylkill County; Pokono Mountain, Monroe County, Pennsylvania; at Absecom, Ilainmonton, Woodstown, VinelanJ, Cape May, and other places in Now Jersey; Ncw[)ort and Narragansett, Rhode Island ; and lakes of the Uinta Mountains, Wyoming Territory. A large Aiuwba is the subject of the earliest notice of a Eresh-watei I t I '■i ¥ 32 rRESII-WATER UIIIZOrODS OF NORTH AJIERICA. Rhizopod. It was discovered by Riisel, and described in a work entitled "Insecten Belustigung ", or Recreation among Insects, published in Nnrn- berg in 11^)5. Rosel alls the animal the little Proteus, and accompanies his description with nineteen well-executed and colored figures engraved by himself. Linnteus, in the Systema Naturae, referring to Rosel's animal, named it Volvox Chaos, and subsequently Chaos Protheus. Pallas called it Volvox Proteus. Miiller afterwards named it Volvox Spharula, but later, after having himself observed the animal, described and figured it under the name of Proteus difiluens. As the generic name of Proteus had been previously appropriated for the well-known Salamandroid of Adelsberg, Bory de St. Vincent substituted that of Amiba for the animal of Rosel and Miiller, calling it by the various names of Amiba divergens, A. lioesiU, and A. Mulleri. Ehrenberg, in the Transactions of the Academj;' of Sciences of Berlin for 1830, indicated and figured a comparatively small Amoeba, the i^th of a line (pp. oO, 75, pi. I, figs. 5), under the name of Amoeba diffluens, regarding it as the same as the Proteus diffluens of Miiller. In the Transactions of the following year, Ehrenberg described what he considered to be a new species with the name of Amoeba princeps. The characters given of this are as follows : Diameter 1th of a line; body trans- parent, yellowish, with many easily and voluntarily movable blunt pro- cesses; four times larger than the Proteus. This description is accompanied with one of Amosba diffluens {Proteus diffluens, Miiller), as follows: Diameter Jjth of a line; body transparent as water, mostly with only three or ^our variable processes; four times smaller than the preceding species. In his great work, the Infusionsthierchen, 1838, Ehrenberg described Amaiba princeps as ''large, yellowish, equalling Jth of a lino, provided with a variable number of cylindrical appendages, thick and rounded at the end." The -Accompanying figures (Taf VIII, Fig. X) accord with the description, and agree with the familiar oonmion large Amoeba. In the same work, Amaba diffluens u described as " rarely surpassing the jjth of a line, hyaline; processes variable, moderately long and robust and subacute." Under this species, Ehrenberg jdaces as synonyms the GENUS AMffiBA— AM(EBA TROTEl 8. 33 Hjy names of all forms of Amoeba previously described by others, including the one first discovered, the little Proteus of Rosel. In the earlier description of Amoeba princeps, Ehrenberg says it is four times larger than the Proteus, meaning the Proteus diffluens of Miiller and his own Amoeba diffluens, but not the Proteus of Rosel; for this, according to the actual representation of the latter, is four times larger than Amoeba princeps, and sixteen times larger than Amoeba diffluens, nccording to the measurements of these given by Ehrenberg. In the remarks on Amoaha princeps, in the Infusionsthierchen, Ehren- berg says " it is true that Rtisel described a larger species of Proteus of which the dimension accords with this, but the blunt processes, of the species occurring in Berlin, do not agree well with those of Rosel's figures, but rather approximate those of larger individuals of Amoebo diffluens!'^ It is natural to suppose that an Amoeba discovered by the earliest microscopic observers would be one of the more conmion large forms, and that such was the case appears to be fairly proved by figures and descrip- tions. Rosel, in refemng to one of his figures of the little Proteus, remarks that in its natural size it looked like A. Now, this figure A represents the animal in its quiescent state, in globular form, and the figure measures just four fifths of a line. No Amoeba has since been recorded, in the same condition, so large as this, and it is not unfair to suppose that the figure is somewhat exaggerated, which could readily occur in absence of the accurate means of measurement which came subsequently into use. Rosel refers to his having held his little Proteus at rest with a pointed feather, which is alone sufficient to prove that he had under his observation one of the largest forms of Amoeba. In size, according to the actual measurements given, Rosel's Proteus is as much larger than Amoeba princeps as this is than Amoeba diffluens. In all other characters ascribed by Ehrenberg to Amoeba princeps, it appears to the writer to agree with the Proteus of Rosel, and this without doubt better than does the Amoeba diffluens as described by Ehrenberg. Amoeba princeps is said by the latter to be yellowish, while the Amoeba diffluens is said to be clear as water. Though Rosel says nothing of the color of the Proteus, his figures, carefully colored, exhibit the granular 3 BUIZ 34 FRESn WATEU UniZOPODS OF NORTH A?.i ERICA. contents yellowish, and the exterior investment colorless, just as our largo common Amoeba appears under partially reflected and transmitted light. Most of Rosel's figures exhibit the characteristic changes of form of the Proteus, and these certainly agree with those cf our common large Amtt3ba, and better with those of Ehrenberg's figures of Amoeba princcps than with those of the same author's figures of Amwha diffluens. Of the figures of Rosel, one ho likens in its branching to the antler of a deer, a resemblance which all must have seen who are familiar with the large Amoeba commonly regarded as the Aniceba princeps. As regards both size and color of the Proteus of Rosel, it might refer to other large Ama-ba) than A. pr'mceps, as for instance the A. villosa of Wallich, or the Pclomyxa pahistris of Greeff; but the changes of form and the extension and shape of the pseudopods rather approximate it to the former. Miiller's description and figures of Proteus diffluens, Avhich that author regarded to bo the same as Rosel's Proteus, appear to apply to the same animal as Ehrenberg's Amoeba princeps, rather than to the Amoeba diffluens of the latter. From the review thus presented, I think it will be admitted that the little Proteus of Rosel, the Proteus diffluens of Midler, the Atnoeba princeps of Ehrenberg, and our large familiar Amoeba, ai'e to be regarded as one and the same animal. It has been suggested that all forms of Amoeba may eventually be found to be transitory phases of the same species ; but even this view does not render the determinations of Ehrenberg and those who follow him in relation to Amoeba princeps and Amoeba diffluens any the less incorrect. Having arrived at the conclusion that our common large Amoeba, usually called Amoeba princeps, is the same as Rosel's Proteus, the question arises as to its appropriate name. Ehrenberg changed the name of Amiba of Bory into Amoeba ; and had it not been that the latter mode of spelling the word had come into such common iisie, I would have dropped the ugly diphthong, and resumed the word Amiba, as employed by Bory and Dujardin. Of the specific names employed for the little Proteus, that of chaos in Volvox Chaos of Linnaeus is oldest ; but that of proteus in Volvox Proteus of Pallas appears more appropriate, and would at the same time serve to .— *y OKNIIS AMa<}HA— AMCKJtA PROTEUS. 86 perpetuate the name jjiven to the animal by its discoverer. I therefore suggest tliat the name of Amcehu protcus shouhl be employed for the common large Amoeba, recognizable as the Proteus of Rosel and the Amaba princeps of Ehrenberg ; otherwise, according to the strict rules of scientific nomenclature, it should be Amoeba chaos. Amoeba proteus (pis. I, II) is one of the largest forms of the genus, and is the one which is perhaps the most familiar to those who are accustomed to the examination of the microscopic life abounding in fresh waters. It is commonly found in the superficial ooze of clear and comparatively quiet waters, such as ponds, lakes, and ditches. It also occurs among Duck-meat and on the under surfiico of leaves of aquatic plants floating on the surface of water. In some instances, in certain localities, it may be found in profusion; but frequently in similar places, or even at other seasons in the same place, I have failed to obtain it after the most diligent search. Specimens often vary, especiall)- in different localities, to such a degree that it is difficult to decide whether to regard them as really pertaining to this or some other described species. The habitual appearance of characteristic forms as they have come within my notice may be described as follows : The Amoeba, if observed immediately after having been transferred from the material in which it lived to the object-glass of the microscope, appears as a globular or ovoidal, granular ball, translucent and of a blackish hue by transmitted light, or faintly yellowish white by reflected light. Often, however, from the first moment of observation, the animal appears of irregular shape, with projected pseudopods already in movement, apparently as if it had been little affected by disturbance. The globular or ovoidal quiescent Amoeba after a little while puts forth from every part of the body a multitude of clear, rounded extensions of the ectosarc, which give one the impression that the creature had sud- denly exuded, or, if I may use the terra, sweated, numerous drops of liquid. These quickly elongate, and assume the form of digitate pseudopods, in which condition the animal may present the appearance seen in fig. 1, pi. I. A number of the pseudopods continue to elongate and become thicker, not only from an extension of the ectosarc, but by the attendant influx of the endosarc. The greater number of the pseudopods originally seen are 36 l>'RKSn WATKU imiZOF'ODH OF NORTH AMEllIOA. withdrawn and altogether disappear. The growing psoudopods are cylin- drical or digitate, with blunt extremities. They extend in all directions, are usually more or less curved, and frequently branch. In this condition, the Amoeba may jjresent the appearance represented in fig. 2. Occasionally iho rounded or ovoidal mass composing the body of the Amoeba, after ])utting forth ntunerous processes in the manner above described, withdraws the most of these, while a few others rapidly elongate, and diverge on each side, and the animal may assume a shape reminding one of a great spider. A specimen in this condition is represented in