The author's “Observations” relate mainly to the Microscopic Anatomy of the reproductive tissues and corpuscles of about fifty Lichenicolous Parasites—apparently new species—referable partly to the true Fungi, and partly to the Fungo-Lichenes. These parasites, themselves microscopic, have accumulated in the author's Herbarium during the last twelve or fifteen years: or were examined by him while determining the species of various British and foreign Lichen-collections submitted for that purpose during the same period.