Description of Dolichodorus cobbi n. sp. (Nematoda: Dolichodoridae) with Description of Dolichodorus cobbi n. sp. (Nematoda: Dolichodoridae) with Morphometrics and Lectotype Designation of D. heterocephalus Cobb, 1914

Dolichodorus cobbi n. sp. is described and illustrated from soil around roots of "woods" on the Stanley Farm, Scott County, Arkansas. This species is distinguishable from others of the genus by its short tail projection. It is most closely related to D. marylandicus but differs in having a short tail projection, longer stylet, greater body length, larger c value, and also in position of excretory pore. A limited number of Cobb''s original specimens and drawings of D. heterocephalus were examined. A lectotype and paralectotype were designated to establish the taxonomic base for the genus. Cobb''s original modified labeled drawing of D. heterocephalus is also included. Morphometric data on D. heterocephalus from the type locality and several other populations are given. Some variations in female tail shape, body length, and stylet length were noted.     

THE HOST RANGE OF THE CHLORELLAVOROUS BACTERIUM ("VAMPIROVIBRIO CHLORELLVORUS")

The chlorellavorous bacterium . "Vampirovibrio chlorellavorus" Gromov et Mamkaeva, grows only by killing and consuming the cell contents of species of the green alga Chlorella Beijerinck. Of the 76 algal strains examined in this study, the bacterium attacks all 31 strains of the species C. vulgaris. C. sorokiniana, and C. kessleri, but attacks only two of 39 strains of nine other Chlorella species. Neither of two Prototheca strains was susceptible to attack. This narrow host specificity may be related to cell surface properties .     

居群（population）概念和方法在植物分类学中的应用

本文依据我们近几年来对水生维管束植物的研究成果,讨论了居群概念和方法对植物分类学的理论和实际的意义与价值,同时对我国今后展开植物学研究提出了若干建议。     

Dolichodorus miradvulvus n. sp. (Nematoda: Tylenchida) with a Key to Species

Dolichodorus miradvulvus n. sp. from Anubias nana Engler in Florida is described and illustrated. The female is characterized by deep grooves in the cuticle on the ventral surface just anterior and posterior to the vulva, and by transversely elongate pouches anterior and posterior to the vulva. Both sexes have a constricted area of the stylet shaft just anterior to the knobs, and on the male the intersection of the lateral field and bursa appear sclerotized.     

A revision of the genus Paradoxostoma Fischer (Crustacea; Ostracoda) in British waters

Species of the genus Paradoxostoma Fischer are an important component of marine and estuarine ostracod faunas throughout the world. This revision of the genus in British waters deals with 17 species of which six are described as new. Each species is diagnosed and illustrated in detail, and comments are made on their ecology and distribution. The specialized mouthparts which characterize the genus are illustrated by means of the scanning electron microscope for the first time. A key to the genus is given.     

Numerical taxonomic analysis of cross-inoculation patterns of legumes and Rhizobium

Summary A survey was made of published results of tests of the capacity of Rhizobium derived from one legume genus to nodulate plants from other genera. The data were derived from more than 14,000 separate cross-inoculation trials involving species from 165 genera of legumes. Numerical taxonomic techniques were applied to 113 of the genera for which results of substantial cross-infection tests were available. The data were examined using mean character difference coefficients re-expressed as total and positive-only similarity coefficients. The resulting similarity matrices were clustered by the unweighted pair-group method using arithmetic averages. Eighteen affinity groups were defined at the 70% similarity level. With few exceptions, the physiological and cultural behavior of the rhizobia was consistent within the defined groups. Two broad categories were suggested in the numerical taxonomic analysis, and their validity is discussed in regard to the geographic, physiological and cultural characteristics of the legumes and their Rhizobium microsymbionts. The taxonomic and agronomic value of this approach and the new groupings are discussed.     

Chemical structure of the lipid A component of Plesiomonas shigelloides and its taxonomical significance

Abstract The chemical structure of the lipid A moiety of the lipopolysaccharide of the type strain of Plesiomonas shigelloides was elucidated. It consists of a β-(1 → 6)-linked glucosamine disaccharide carrying phosphate groups at C-1 of the reducing and at C-4' of the non-reducing glucosamine. It contains a total of 6 residues of fatty acids, 2 amide-linked and 4 ester-linked. The amino groups of the backbone disaccharide are N -acylated by substituted 3-hydroxyacyl residues: at the reducing glucosamine by 3-O-(14:0)14:0; and at the non-reducing glucosamine by 3-O-(12:0)14:0.
Two residues of 3-hydroxytetradecanoic acid are linked to C-3 and C-3' of the glucosamine residues; the hydroxy groups of these ester-linked 3-hydroxytetradecanoic acids are unsubstituted. In free lipid A, the hydroxyl groups at C-4 and C-6' are unsubstituted, indicating that the 2-keto-3-deoxyoctonic acid (KDO) is linked to C-6' of the non-reducing glucosamine, as was shown with enterobacterial lipid A. The taxonomical significance of these structural details is discussed.     

The genus Mixodiaptomus Kiefer, 1932 (Copepoda,Diaptomidae) in Spain

The distribution of the Calanoid genus Mixodiaptomus was studied in a large number of pools and small lakes scattered over Spain. Four species occur: M. incrassatus, M. kupelwieseri, M. ortizi and M. laciniatus, the latter in 2 subspecies (M. laciniatus laciniatus and M. laciniatus atlantis). M. ortizi is described as a new species. M. laciniatus lives in mountains, while all other species occur in the plains. M. incrassatus is found all over the country, M. kupelwieseri only in the eastern part of Catalonia, M. laciniatus atlantis in Andalucia and M. ortizi in the central lands called Mesetas. All live in little mineralized waters and only M. incrassatus and M. laciniatus atlantis occur in clayey waters.