Page:Journal of botany, British and foreign, Volume 34 (1896).djvu/233

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A NEW VARIETY OF ENTERIDIUM OLIVACEUM EHRENB. 211 in the clustered spores, but in the structure of the sporangium- wall, which is shining and smooth, with minute granular matter diffused throughout its almost homogeneous substance. In Licea flexuosa the wall has a dull opaque appearance, occasioned by the deposit of refuse matter in the form of rough aggregations spread over the surface of the membranous inner layer. In examining several specimens of the new form, we also find that a pseudo- capillitium is by no means universally absent, but in some cases the plasmodiocarp bears on its inner surface membranous bands and folds connecting the base with the upper wall, having a strong resemblance to the pseudo-capillitium in an sethalium of E. olivaceum, though developed to only a small degree. Taking the above charac- ters into consideration, there is reason to conclude that, notwith- standing the wide difference in general appearance from the usual aethalioid form of E. olivaceum, these gatherings should be classed as a variety of that species. At the same time, on account of the constancy of the plasmodiocarp habit exhibited in the four gatherings which have come under my notice, it is entitled to a distinct varietal name, and I propose to mark it as R. olivaceum var. liceoidesr' Within a few yards' distance from the specimens of the above- named variety found at Leighton Buzzard, a few small aethalia of E. olivaceum were gathered, of pulvinate form, and with the pseudo- capillitium perfectly developed; but in these the spores were free, with no appearance of the usual clustering, though in all other respects they were typical, and like other gatherings found in the same plantation with clustered spores. A similar form with free spores is in the collection of Prof. Balfour. A type specimen of Enteridium Rostrupii Kaunk. has courteously been supplied to the British Museum by Dr. Raunkier, of Copen- hagen. It is a thin aethalium, and, having dried too quickly, is not perfectly mature, otherwise it is a typical form of Enteridium, olivaceum. It has the uSual pseudo-capillitium consisting of the perforated walls of the component sporangia, and the clustered spores measuring 10-12 /a diam., of the same size as those in the type specimens of the latter species in the British Museum, Kew, and Strassburg herbaria. It is part of a longer aethalium, and is 2-5-4 mm. broad, 19 mm. long, and 0-4-0-75 mm. thick ; the diameter of the sporangia composing the aethalium is 0'2-0"3 mm. Dr. Raunkier explains in a letter that, finding the spores to be so much larger than the measurements given by Schroeter, viz. 6-8 /x, he published the description of his gathering under a new name, "until more could be known about it." The sethalium does not consist of "one layer of sporangia,"! but preparations from the thinnest part so much resemble those of the plasmodiocarp of var. liceoides that it confirms the opinion that the latter is a form of E. olivaceum.

  • In the description of Licea fiexuosa in the British Museum " Guide to the

British Mycetozoa," p. 32, the spores are mentioned as sometimes occurring in clusters, a character based on the Appin and Leighton specimens. On the view here adopted this statement should be omitted from the account of the species. t Cfr. British Museum Catalogue of Mycetozoa, p. 169. p 2