Henry Allison’s interpretation of Kant’s First Analogy is among the most intriguing in the literature. Its virtues are considerable, but no previous discussion has done full justice to them. Nor has any previous discussion systematically explored the most important challenges to which it seems subject. This paper does both. Early sections provide a more thorough exegesis than is otherwise available and provide stronger textual backing than does Allison himself. Later sections turn to problems, most of which have not been raised by others. These problems, while serious, do not necessarily rule out the interpretation of Allison.

Matter’s real essence is a ground for certain features of phenomena. Things in themselves are likewise a ground for certain features of phenomena. How do these claims relate? The former is a causal essentialism about physics, Stang argues; and the features so grounded are phenomenally nomically necessary. The latter involves a distinctive ontology of things in themselves, I argue; but the features so grounded are not noumenally nomically necessary. Stang’s version of Kant’s modal metaphysics is admirable, but does not go far enough. Kant’s causal essentialism involves the essences of fundamental properties, as well as of matter. And things in themselves are grounds, because they are substances, the ‘substrate’ of phenomena.

The occurrence of 12 Usnea species in Estonia is verified by investigating c. 1800 specimens. The known distribution and substratum preferences of Usnea taxa in Estonia are summarized. Picea is the main substratum for Usnea species in Estonia, but occasionally these species occur also on deciduous trees, wood, and exceptionally on rock. A key for identification of 16 taxa recorded in the three Baltic countries is provided and diagnostic morphological and chemical characters used in the key are discussed. A new chemotype of U. fulvoreagens has been identified. U. wasmuthii is reported as new to Lithuania.