. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Section of fruitful thallns of Sticta pulmonacea, about 20 diam. a, discoid apothecium. The vertical lines indicate the lamina proligera; s, spermogouia containing sperniatia; i, empty spermogonia. six to eight cylindrical cells, joined end to end; and secondly, the thecce, which are obovate vesicles, each containing, almost in- variably, eight spores. These elements are arranged side by side, their long diameters being perpendicular to the surface of the apothecium. They appear to be glued toge- ther, even in the fully
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Section of fruitful thallns of Sticta pulmonacea, about 20 diam. a, discoid apothecium. The vertical lines indicate the lamina proligera; s, spermogouia containing sperniatia; i, empty spermogonia. six to eight cylindrical cells, joined end to end; and secondly, the thecce, which are obovate vesicles, each containing, almost in- variably, eight spores. These elements are arranged side by side, their long diameters being perpendicular to the surface of the apothecium. They appear to be glued toge- ther, even in the fully formed apothecia, by an intermediary gelatinous substance, which, however, there is good reason for supposing to be nothing more than a thickening of the external membrane, from which it cannot be distinguished, either in respect of its chemical or other characters. Iodine colours this substance, as well as the external mem- branes of thecae and paraphyses, blue, without the addition of sulphuric acid. In the early condition, the cavities of the thecas are occupied by a yellow, plastic material, out of which the spores are afterwards formed. The thickness of the external starchy mem- brane is at this period relatively more consi- derable than later; as the spores increase in size, it gradually diminishes. The struc- ture of the fully formed spore is best ob- served in those species in which it is largest. The spore-membrane, of considerable pro- portional thickness, is smooth and semi- transparent, wholly unaltered by iodine and sulphuric acid. The contents consist partly of mucous granules, which are coloured brown by iodine, partly of yellowish oil globules. The whole is usually invested, even after its escape from the theca, with the still adherent remains of the inner proto- plasmic layer, by which it was immediately surrounded. In form, the spores are most frequently ellipsoid and unilocular. In other instances, however, they are divided by one or more partitions. This di
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