David G Hobbs

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Recent molecular work has confirmed the long-standing morphological hypothesis that capuchins are comprised of two distinct clades, the gracile (untufted) capuchins (genus Cebus, Erxleben, 1777) and the robust (tufted) capuchins (genus Sapajus Kerr, 1792). In the past, the robust group was treated as a single, undifferentiated and cosmopolitan species, with(More)
The chick was used to investigate the incidence of vesicles, 60-75 nm in diameter, previously observed (Chandler et al. 1975) associated with the intestinal brush border of various animals. Samples were taken from 3 positions in the small intestine, from the duodenum, 20 nm proximal to the yolk stalk and 100 mm proximal to the ileocaecal junction, and(More)
The changes in wall structure of two penicillinase-negative strains of Bacillus licheniformis on addition of penicillin were studied. After addition of penicillin to give a concentration of 1 unit/ml, exponentially growing cells of strain 749 c/72 doubled once and then stopped. Strain 749c/72/IIIg was more resistant and continued growing, but synthesis(More)
The changes in wall structure of a penicillinase micro-constitutive strain of Bacillus cereus (569/H/24), on exposure to penicillin, and after its removal by addition of penicillinase, have suggested the following model for the growth of the walls of these cylindrical cells. Longitudinal extension is by addition of material to a large and continuously(More)
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