ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02524.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.Photokinesis or the non‐directed rate of swimming ofEuglena gracilisfor various light intensities was studied. The rate of swimming in white light was found to increase with light intensity until it reaches 0.16 mm./sec. at a saturation of 40 ft. candles, and then decreased with increasing light intensities. Polarized light appeared to be more effective (0.18 mm./sec. at 13 ft. candles) than non‐polarized light.The action spectrum forphotokinesisshowed two peaks, a major one near 465 mμ, and another in the neighborhood of 630 mμ, having the values of 0.18 mm./sec. and 0.16 mm./sec. respectively at an intensity of 4 ft. candles.The action spectrum forphototaxis, or directed orientation, had a peak near 420 mμ and showed a maximum near 490 mμ. Both dark‐grown and dark‐adaptedEuglenashowed spectral peaks similar to those of the light‐grown cells. For polarized light, the action spectrum had two additional peaks at 468 mμ and 508 mμ. The polarized light effect may indicate more than one light‐absorbing pigment within the “eye spot” or that other pigments within

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02525.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.The role of eleven different types of achromatic figures in chromosomal movement ofBarbulanymphais analyzed. When only one pole is present, no chromosomes are ever connected with it, and hence they do not move. The chromosomes go through their usual life cycle including pairing, but remain in the parent nucleus, which, of course, does not divide. When two poles are present with only one pole near the nucleus, the poles, which are the distal ends of the elongate centrioles, do not cooperate in the formation of a central spindle and the chromosomal behavior is just as if there were only one pole—no movement. The same is true when more than two poles are present with only one near the nucleus.Unless a central spindle is present, movement of chromosomes never occurs. However, when many central spindles are present, sister chromosomes may separate and move to poles which are not directly connected by a central spindle. In other words, sisters may separate without moving along a central spindle.In binucleate cells with one central spindle the chromosomes of one nucleus move to the poles, but those of the other do not. Movement always occurs in the nucleus that has its nuclear membrane depressed by the central spindle. When two or more central spindles are present, the chromosomes of both nuclei may move to the pole

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02526.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.A description is given of the formation of an unusual type of achromatic figure by two very long, narrow centrioles. The unique manner in which this structure functions in chromosomal movement is explained.

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02527.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.Coprozoic protozoa from elk, bison, bear, moose, coyote, marmot, cattle, horse, sheep and man were kept in feces at 4° C. for 2–6 months. During that time in most of the samples there developed the flagellatesCercomonassp.,Copromonas ruminantiumandMonas communis;the amoebaeVahlkampfiasp. andSappinia diploidea, and ciliates of theNyctotherustype, and an unidentified smaller species. There was a correlation between numbers of protozoa and bacteria. The same species of protozoa in soil or in soil mixed with boiled feces failed to live. Coprozoic protozoa may require certain essential metabolites from bacteria as do true parasites. The wide variation in appearance of cysts made it practically impossible to identify the protozoa with certainty in that stage. Reliance had to be on motile forms which readily developed in the cold cultur

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02528.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.The nutritional requirements of 3 isolates ofPrymnesium parvum(2 Israeli, 1 Scottish) included vitamin B12and thiamine. For comparison, 2 other brackish chrysomonads were studied:Monochrysis lutheriisolated by Droop in Scotland andIsochrysis galbanapurified by McLaughlin from a culture obtained from the Plymouth laboratory.The isolates ofPrymnesium parvumandIsochrysis galbanahad a molecular B12specificity likeOchromonas malhamensis: no response to Factor B, pseudovitamin B12, Factor A or Factor H.M. lutheri, in contrast, responded to pseudovitamin B12, Factor H, and Factor A.Thiamine was essential; 1.0 μg.% allowed full growth ofP. parvum.The NaCl concentration for good growth was 0.3–5.0%; growth was possible from 6–12%. Dark growth was not achieved.Ammonia, as suggested from its use in suppressing outbreaks ofP. parvum, was sharply inhibitory, less so at high concentrations of NaCl or at acid pH.Nitrate, ammonia, arginine, asparagine, methionine, histidine, alanine, glycine, serine, proline, leucine, isoleucine, tyrosine, aspartic and glutamic acids, acetylurea, and creatine served as nitrogen sources in both acid and alkaline media.The phosphate requirement ofP. parvumandM. lutheriandIsochrysis galbanawas satisfied by inorganic phosphate, commercial glycerophosphate, yeast adenylic acid, cytidylic acid, monoethyl phosphate, and riboflavin monophosphate.Laboratory cultures in defined media of the isolates ofP. parvumwere toxigenic toLebistesandGambusia.Culture fluids from alkaline media were more toxic than those from acid media, as previously noted in Israel.Culture media suitable for production of large quantities of these organisms were devel

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02529.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.Four new species ofEimeriaare described from small mammals in Liberia. These are:E. levinei, sp. nov. from a free‐tailed bat,E. firestonei, sp. nov., andE. milleri, sp. nov., from a shrew, andE. putevelata, sp. nov., from a striped grass mous

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02530.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.Euplotes eurystomusWrzesniowski was cultured on bacterial media withTetrahymena pyriformisserving as the food organism. Animals were injured with various types of operations using the Chambers' micromanipulator. These animals were followed during the course of their regeneration using various nuclear stains, silver impregnation techniques and vital staining methods. It was found that two cirral fields arose as a result of injury removing one or more of the locomotor organelles and that the posterior field was soon resorbed, while the anterior one replaced all of the old cirri of the regenerating animal. In addition, in response to this sort of injury, complete nuclear reorganization took place. Animals which were injured in a manner not affecting the locomotor organelles directly, responded by proliferating a fine network in the area of injury. This network seemed to reinforce the injured area and persisted until the next binary fission of the animal. No nuclear reorganization took place in these cases.

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02531.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.Certain aspects of the metabolism of aTrichomonas batrachorum‐type flagellate from the cecum of swine were studied. This trichomonad (1) oxidized glucose, mannose, maltose, sucrose, and inulin, (2) was incapable of oxidizing Krebs' cycle intermediates, (3) possessed peroxide‐splitting capabilities, (4) was inhibited by only iodoacetate and arsenite, and (5) formed acid(s) aerobically. Although there was no effect on oxygen uptake, pyruvate and lactate increased the anaerobic evolution of gas(es). In addition to CO2, other gas, not absorbed by KOH, was produced anaerobically.Compared with other porcine trichomonads, the metabolism of this small trichomonad resembles most closely that of the large cecal trichomonad,T. suis.However, the smaller trichomonad had a generally lower respiratory rate, a slightly lower optimal pH, and failed to oxidize fructose, galactose, lactose, raffinose, and trehal

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02532.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY

摘要:

SYNOPSIS.A new species ofStentoris described, a fresh water form, medium sized, with cerulean blue pigment, and characterized by retractable feeding organelles.

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1958.tb02533.x

出版商:Blackwell Publishing Ltd    

年代:1958

数据来源: WILEY