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Two ciliate species of Blepharisma were collected from the riverine wetland and mountain peak soil in Korea, Blepharisma undulans Stein, 1867 and B. steini Kahl, 1932, which are reported for the first time from Korea. The description was based on the observations of live and protargol impregnation specimens. Diagnostics of these species (Blepharisma undulans vs. B. steini) are as follows. Body length/width ratio in vivo about 6/1 vs. 2/1, shaped in spindle vs. pyriform to ellipsoid and colored in pinkish vs. reddish. Macronuclei 2 vs. 1, with 4-9 vs. 4-7 spherical micronuclei. Adoral zone of membranelles extends from anterior end to 1/3 vs. 1/2-2/3 of body length, with 47-56 vs. 33-45 adoral membranelles. The numbers of somatic kineties are 22-27 vs. 18-22.

Previously published field studies have suggested that the concept of r/K selection may be applied to terrestrial ciliates. A census was taken of the dominant groups, the Colpodea and Polyhymenophora, to determine species composition and absolute abundances in climatically unpredictable alpine and predictable lowland sites. In addition, two typical representatives of each of the two taxa (Colpoda aspera and Grossglockneria acuta, and Blepharisma undulans and Gonostomum affine, respectively) were selected for examination under laboratory conditions. Variables investigated were: the C/P index (ratio of Colpodea to Polyhymenophora), fertility, tolerance of altered environmental conditions, incidence in predictable or unpredictable biotopes, opportunism, competitive ability, and body size. Our own observations were supplemented by reference to the literature. The field census produced a higher C/P index in the unpredictable sites than in the predictable ones. The experiments show that C. aspera and G. acuta are less sensitive to changes in temperature and exhibit a more rapid rise in individual density as well as a higher number of individuals than do B. undulans and G. affine, although the former species have longer generation times at low temperatures. The explosive increase in number of individuals can be ascribed to the special reproductive strategy of the Colpodea (quadripartition in cysts). These results imply that the Colpodea are more r-selected as compared with the Polyhymenophora. That might be an explanation for their wide distribution and high density in unfavourable terrestrial habitats.

1. 1. The effect of selected dosages of monochromatic ultraviolet light of wavelengths 238, 245, 253, 265, 280, 302, 313, 366 mμ were studied on the following: 1) regeneration of cut Blepharisma ; 2) division rate; 3) conjugation; 4) survival of colored and bleached individuals. 2. 2. No evidence for photoreactivation could be demonstrated in the ultraviolet injured animals. 3. 3. Fission was most delayed at wavelength 280 mμ at the first division, but a somewhat longer delay was observed at 254 and 265 mμ for the third division. 4. 4. The action spectrum for survival after large dosages of ultraviolet light best fits a curve that is a composite for a mixture of nucleic acid and protein, rather than either substance alone.

SYNOPSIS. An analysis of the pigments from the protozoan Blepharismn undtulans is reported. Methods of isolation and separation by paper chromatography are described. along with subsequent spectrophotometric and chemical analysis. Since the two major pigments were available only in amounts insufficient for thorough chemical analysis, these pigments were compared with the known pigment hypericin. Although similarities in the visible spectra indicate that the B. unduluns pigments possess the same mesodianthrone structure as hypericin, infrared spectra and chemical reactions disclose differences in the position, and possibly in the number, of the functional groups. A tentative structure is proposed.

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SYNOPSIS. An account of conjugation in an American species of Blepharisma is given. A comparison is also made with the available knowledge of the two Indian species of this genus. In the conjugating pair, the condensed macronucleus shows Feulgen negative regions. Before the conjugants separate, the macronuclear and micronuclear anlagen become distinguishable. The species is characterized by a number of striking features which become noticeable after syngamy. The synkaryon divides thrice giving rise to 8 bodies. Of these, 3 to 7 become the macronuclear anlagen and the rest, the micronuclei. The resorption of the old macronucleus occurs much later, just before the exconjugant attains the vegetative form. No metagamic fissions occur in this species and each exconjugant becomes a vegetative animal in 5 or 6 days. During this period, the macronuclear anlagen arrange themselves in a series and develop slender connections with one another to produce the moniliform macronucleus of the vegetative animal. The micronuclear anlagen, on the other hand, divide by mitosis to attain the vegetative number. In this species 40% to 45% of the exconjugants are viable and the rest die.

1. It has been observed, that when Blepharisma undulans is treated with strychnine sulphate, morphine sulphate and several other chemicals the pellicle is shed. The pellicle and the " naked " animal have been studied.2. The pink color so characteristic of this animal is restricted to the pellicle.3. The pellicle is not essential for life, division or motion and its character is dependent on the amount of food available.4. Under favorable conditions the pellicle is easily regenerated.

SYNOPSIS. A full account of the nuclear changes during binary fission and conjugation in a local race of Blepharisma is presented in this paper. The macronucleus consists of 2 nodes connected by a strand. Number of micronuclei varies from 6 to 18. During binary fission, condensation of macronucleus is followed by elongation and thinning of the middle region which finally breaks. Daughter nuclei later attain the typical vegetative form. Notably, during binary fission some micronuclei appear to complete their mitoses by the time the macronucleus attains the condensed form, while others lag behind and exhibit practically every stage of mitosis. During conjugation, from 6 to 10 micronuclei undergo the first pregamic division, the same number through the second division, and two products of the second division take part in the third division. The rest degenerate. Division products of the nuclei in the paraoral region take part in synkaryon formation. The synkaryon undergoes either 2 or 3 divisions. In the former case, of the 4 products, 2 become the macronuclear anlagen, one the micronucleus and the fourth degenerates. In the latter case, of the 8 products, 3 to 4 become the macronuclear anlagen and the rest become micronuclei. Chromatin elimination has been observed during the division of the macronuclear anlage, followed by an extra metagamic fission of the cell. Comparison with two other races from India and an American race indicates considerable diversity in the structure and behaviour of the nuclear apparatus in different races of Blepharisma undulans.

1. Blepharisma undulans, a protozoan with a reddish pigment, shows increased oxygen consumption under the influence of light. 2. If the light intensity is high, the animals are killed during a burst of oxygen consumption. 3. If the blepharismas are first bleached by exposure to light of low intensity they show only slightly increased oxygen consumption under the influence of light and they are not killed. 4. A preparation in which the animals are killed by heat still shows the increase in oxygen consumption on illumination with brilliant light. The supernatant solution does so as well, as does an alcohol extract of the dye. 5. The conclusion is drawn that the blepharismas are killed during photooxidation of the pigment, but the mechanism of action is not clear. Several possibilities are considered in the discussion.

1. Previous analysis of the division rates of Paramecium aurelia (mutant), Blepharisma undulans, and Histrio complanatus grown separately in pedigree isolation culture, under as nearly identical conditions as possible, for a period of 3 years, disclosed a secular trend and a seasonal rhythm for each organism. The seasonal rhythm has a maximum in July.2. This seasonal rhythm is shown to be related to the amount of sunshine reaching the locality of the cultures. The maximum amount of sunshine is received in July also.3. After the effect of trend and the influence of the amount of sunlight are removed from the division rates, they show no relation to each other except for deviations caused by known changes in the culture technique. Each organism has a division rate varying independently of the others, when the effect of external unifying influences are removed.4. Consequently, the amount of sunlight, other conditions held constant, seems to determine the similarity of the division rate of these diverse organ...

1. Two ciliates, Blepharisma undulans and Paramecium caudatum, were studied with reference to form stability and integrity (resistance to cytolysis) under varying conditions of hydrostatic pressure (up to 10,000 lbs./in.2) and of temperature (12°-25° C.).2. At lower pressures the specimens retained their elongate form, but at higher levels, depending on temperature, species, and age of the cloned cultures, the cells gradually become shorter and more rounded. Following this form change, cytolysis occurred in a varying percentage of the specimens. Older cloned cultures showed a greater and more variable susceptibility to the pressure-temperature effects, so that selected younger cultures were used for the quantitative evaluations.3. For Blepharisma, the critical pressure, which gave 50 per cent cytolysis within a 15-minute compression period, displayed a distinct temperature dependence, being 8000 psi. at 12° C., 8700 at 15° C., 9200 at 20° C., and 9300 at 25° C. Paramecium, in contrast, showed a distinctly...

Ithas been shown by Pearl(†07) thatin Parama@ciumcultures the conjugants differ from the non-conjugants in size and varia bility and that a correlation in size occurs between the two members of conjugating pairs. He has shown by statistical methods (r) that the conjugants are less variable in size than the non-conjugants, (2) that the conjugants show a smaller mean size than the non-conjugants, and (@) that a marked correlation in size exists between the members of the conjugating pairs, the smaller uniting with the smaller and the larger with the larger. Jennings (†II) took up the problem of size relationships in Paramwcium going into discussion of the reasons for the condi tions found, which he based on very careful observations of the conditions existing in his cultures. After careful measurement of a great many individuals he confirmed the results obtained by Pearl, i. e., (i) that the conjugants are smaller than the non conjugating population of a culture; (2) that they are less variable than the non-conjugants; and (@)that there is a marked correlation in size between the members of the pairs, so that on the whole larger individuals are found mated with larger, smaller individuals with smaller. It was with the idea of investigating the size relationships in another related form, that the present work on Biepharisma undulans was taken up. It will be possible here to give the facts of the size relationships only as they were found in material already mounted. The individuals under consideration are from a pure-line culture isolated at Woods Hole on July 20, 1911, by Professor Calkins. The six lots with which I shall deal were killed by him at various times during October, 191 I, by means of sublimate acetic, stained with Hoyer's picrocarmine, and mounted permanently in Canada balsam. In measuring the individuals, a Leitz projectoscope was used

SYNOPSIS. The Indian race of Blepharisma undulans described in this paper measures 150 μ in length. The macronucleus consists of 5–7 nodes, all of equal size. During binary fission, condensation of macronucleus is followed by its elongation and a thinning of the middle region which breaks with the division of the animal. It later attains the typical vegetative form. During conjugation 7 or 8 micronuclei pass through the first pregamic division, 5 to 7 through the second pregamic division and one product of the second division takes part in the third division. The rest degenerate. At the same time, the macronucleus also starts degenerating. After the synkaryon has divided twice, the conjugating pairs separate. Of the 4 products, 3 become macronuclear anlagen and one, micronuclear anlage. The micronuclei divide asynchronously both during binary fission and during conjugation. There is apparently considerable diversity in the structure and behaviour of the macronucleus and micronuclei in the different races of Blepharisma undulans.

1. Analysis of the division rates of Paramecium aurelia (mutant), Blepharisma undulans, and Histrio complanatus grown separately in pedigree isolation culture with the same culture medium, and in the same room at any given time, for a period of 3 years, discloses a secular trend and a seasonal rhythm for each organism. The seasonal rhythm is a yearly cycle with a maximum during July. 2. After removal of the effects of trend and seasonal rhythm, no correlation is found between the division rates of the several organisms. The distribution of the division rates is then one of chance order, except for large deviations known to be associated with changes in the culture technique. Each organism has a division rate varying independently of the others. 3. Consequently, seasonal rhythm alone has forced similar variations in the division rates of these three protozoans. The seasonal effect is gradually lost when the animals are raised for several years under laboratory conditions. Examination of the literature discloses other similar cases. 4. It is clear that unless all of the conditions of experiment are kept constant, one must analyze all protozoan division rate data in some such manner as that here presented before any conclusions may be drawn as to the existence of "cycles" or "rhythms."

SUMMARY. Isolated Blepharisma undulans were studied for the following: (1) fission rate, (2) mating behavior, (3) giant formation, (4) effects of daily transections. The organisms were maintained at 22°C. and isolated daily for 60 days. Fission rate varied from two divisions a day to one in 29 days. The major factor producing the variation appeared to be the type or amount of food. Frequency of conjugation also varied greatly. Daughters of a single organism will mate within 24 hours after division. Conjugation followed by one division, re-isolation, then conjugation within 24 hours following a second division occurred within a 5 day period. Giants were produced within 3 days by feeding with Khawkinea, Chilomonas and Paramecium. Paramecium alone did not produce giants. Exposure to 10−m, 10−4M colchicine did not accelerate this process. Daily transections into approximately equal halves were made. The anterior halves containing the mouth membranelles were followed. Fission rate was not affected by cutting. A progressive decrease in size occurred. All ultimately lysed, most on the 7th day. If cutting was suspended on any day, recovery and fission followed. If cutting was re-instituted, lysis would again occur on or about the 7th day. Daily amputation of the posterior tip for 2 weeks did not affect either size, fission rate, or longevity.

Regeneration of Blepharisma undulans variety japonicus from which the hypostome has been removed is retarded by dosages of 3000 to 4600 ergs/mm.2 at wavelength 2654A most strongly when the fragment is exposed soon after cutting. Dosages greater than 4600 ergs/mm.2 prevent regeneration. Regeneration is also retarded strongly when the Blepharisma are cut soon after irradiation. Starvation retards regeneration and potentiates the effect of ultraviolet radiations. Division after regeneration of Blepharisma is also retarded by ultraviolet radiations about equally, regardless of when the Blepharisma are cut indicating a more lasting effect of the radiations upon the cells. Blepharisma cut after irradiation usually recover from the effects of the radiations sooner than uncut individuals given the same dosage. Retardation of division by ultraviolet radiation is subject to photoreversal by visible light, especially in a nitrogen atmosphere, provided the ultraviolet dose is not excessive. Visible light alone if prolonged, retards regeneration or may even kill the cut fragments of Blepharisma.

X-rays and ultraviolet radiations delay regeneration and division of Blepharisma undulans . Irradiated blepharisma which have not been cut divide once or twice fairly soon after the controls then they cease dividing for a period of time (stasis) which may last for many hours or even days. Once they recover from stasis they divide at a rate comparable to controls. Cut irradiated blepharisma on the other hand having to replace lost parts start to divide later than the uncut irradiated individuals but little if any stasis occurs. As a consequence although irradiated with the same dosage cut individuals recover a normal rate of division sooner than uncut ones.

A cytological and experimental study was carried out on conjugations involving more than two individuals of Blepharisma undulans. Attachment of the participants in a conjugating group occurs in a number of characteristic patterns. Regardless of the attachment pattern, nuclear changes occur in all members of a multiconjugant system. These changes are identical in nature and duration to those observed in normal paired conjugation, and occur synchronously in all participants of the system. The stocks of B. undulans used are found to be selfing, physiologically not differentiated into mating types. Multiconjugation can be induced by varying food supply and population density. The probability of autogamous processes in connection with multiconjugation is discussed.

Chromatographic analysis of acid hydrolyzates of the asexual and sexual stages of Blepharisma indicated the presence of 14 amino acids in the asexual animals (I) and 18, including all 14 found in I, in the conjugants (II). The total N content was 2.5 mg./ml. of protein for II and 1.5 mg./ml. for I. The presence of proline, hydroxyproline, threonine, and histidine only in II is significant, but no biochem. significance can be assigned at present. [on SciFinder(R)]

Studies on the life history of Blepharisma undulans have been in progress for over five and a half years, all the animals employed being the progeny of a single individual isolated November, 1921. The work was planned to determine, in particular, the viability of this infusorian in the absence of fertilization, and the effects of fertilization on the rate of reproduction, in an attempt to broaden the results from our earlier studies on Paramecium aurelia1 and Spathidium spatula.2 A preliminary statement of the characteristics of this race of Blepharisma undulans was presented in 1922.4Whereas earlier workers on this organism found that conjugation occurred rather infrequently and invariably was followed by death, conjugation was readily induced in our pedigree cultures, and the exconjugants proved to be viable in nearly every case. Accordingly excellent material was afforded for the problem at hand.Two conclusions may be emphasized from the data secured to date:(1) The animals of this race of Blepharisma ...

In a study of regeneration of form and function at various phases in the life history of the infusorians Spathidium spathula and Blepharisma undulans, it has been determined that the power of restoring lost parts and of continuing normal existence is in all cases dependent upon the same factor, the nuclear content of the fragment. Individuals of known pedigree were cut transversely, and the behavior or the fragments observed until regeneration and division or regeneration and death had occurred. During the vegetative state, regenerative power is highly developed in both ciliates, but because of the more distributed condition of the nucleus in Spathidium than in Blepharisma relatively smaller fragments from either extremity of the former are capable of complete regeneration. All fragments which continue to divide contain both macro and micronuclear material. It has been impossible to produce an amicronucleate race by artificial means.1In Spathidium, where the two nuclear elements extend throughout the cell...

These experiments have been carried out during the past year for the purpose of finding out whether the products of nucleoproteid breakdown have any effect upon the division rate of free-living cells, the ultimate aim being to get some light on the controlling factors of cell division.Two ciliated protozoa were used. One, Actinobolus radians Stein, lives exclusively on a diet of Halteria grandinella, another ciliate. The other, Blepharisma undulans Stein, lives on bacteria. Four control lines of each have been watched, fed, and the number of divisions recorded daily, and curves based upon the averaged division rates for five day periods, give the fluctuations in vitality of the organisms as measured by the division rates. Periods of depression, and of decreasing and increasing vitality have been clearly marked. Individuals for experimentation were in all cases sister cells of the control lines of the same dates.The results show that amino acids and their derivatives have but slight effect on the division ...

Due to the difficulty of carrying on isolation cultures of Stentor coeruleus,1 this protozoan has not been much used in pedigreed culture work. Hetherington2 has recently published a culture method for this organism. He did not, however, continue the culture of Stentor for longer than 7-day periods, and also found some difficulty in keeping Stentor alive, using different types of Protozoa as food, and various media as the basis of his cultures. Beers34 has shown that Didinium can be cultured at a constant division rate if fed on a superabundant diet of Paramecium. At the suggestion and with the advice of Dr. J. A. Dawson, the writer began experiments to determine a suitable method of culturing Stentor coeruleus using Blepharisma undulans as the source of food.A pure line of Stentor coeruleus was begun by isolating a single individual. As a result of 2 successive divisions four individuals were isolated and used to begin a pedigree culture of 4 lines. Each individual was placed in a separate culture dish c...

Studies on Blepharisma undulans and Blepharisma lateritia Stein, have emphasized the impossibility or great difficulty of observing the micronuclei, and also the inevitable death of ex-conjugants without dividing. Thus Butschli1 was unable to identify micronuclei in vegetative specimens of B. lateritia though he found them in conjugants. Exconjugants invariably died. Calkins2 did not find micronuclei in non-dividing B. undulans, but discovered them during division within the macronuclear membrane, and described their emergence and activities during conjugation. He likewise was unsuccessful in obtaining a single viable exconjugant.During the past five months we have had under observation a pedigree culture of Blepharisma undulans which emphasizes racial differences within the species. The animals of this race possess from four to fourteen relatively conspicuous micronuclei, all of which are free in the cytoplasm during every stage of the life of the cell; and all the exconjugants thus far secured proved to...

From a study of the normal and regenerating contractile vacuoles in vivo, evidence was obtained that the normal contractile vacuole in Blepharisma undulans is not a permanent cell organ, but a system of temporary, potentially independent fluid vacuoles.1 In view of the fact that conflicting opinions concerning the permanence of contractile vacuoles have arisen from the failure of investigators to study both living and stained preparations, the above conclusions have been tested by a study of fixed material, derived from the pedigreed cultures. The Nassanov methods and the original Kolatschev technique were employed, not only because of their proved success in demonstrating contractile vacuole structure, but also because by their use the Blepharisma vacuole could be examined in the light of the Nassanov homology.In the several series of preparations which were made, Paramecia, mixed with the Blepharisma prior to fixation and treated identically step by step, were used as controls. Although the contractile ...

In mass cultures of several different races of Blepharisma undulans, including one which has been cultured by the writer for several years and used in connection with other investigations, cannibalism has occurred frequently. This phenomenon has not been very generally noted among ciliate protozoans, as the writer found in reporting a similar case in the Hypotrichida,1 and there are certain aspects of this process in Blepharisma which promise to add to the knowledge of digestive processes in ciliate protozoa.Cannibalism takes place in mass cultures in which growth has been rapid and large numbers of Blepharisma are present. The animal about to become a cannibal is always considerably larger than the individual that is ingested. The process of ingestion is relatively slow, requiring several minutes for completion. Ingested animals are not readily killed by the cannibal but show movements for varying periods, in one case as high as 8 hours. Ingestion is not always followed by digestion of ingested individua...