Morphology and Biology of Some Species of Odontia

Abstract

1. In studying species of Odontia, the use of reagents such as chloral hydrate with iodine and potassium carbonate with eosin has aided in distinguishing structures like cystidia, gloeocystidia, and subhymenial hyphae. The differential action of these reagents on spores, gloeocystidia, cystidia, and other hymenial elements offers supplementary characters for the identification of species. Likewise a knowledge of the corrosive action of these reagents on these structures is important. It has been shown that variations in descriptions of different investigators can in some cases be traced to the difference in the reagents used in the study of specimens. 2. The necessity for revising the generic concept is shown by this study, and an emended description of the genus Odontia Fr. is given. This genus is emended so as to include the species formerly included in the genera Mycoacia (Acia, Oxydontia), Grandinia, Radulum, and Kneiffia. 3. Two new combinations are made, Hydnum fragilissimum B. & C. and H. separans Peck being transferred to the genus Odontia. 4. A study of PECK'S types revealed that Hydnum carbonarium is the same as Odontia fusco-atra; Hydnum serratum and H. balsameum are the same as O. bicolor. 5. The following species were grown in pure culture for the first time: O. fusco-atra, O. uda, O. bicolor, O. arguta, O. sè parans, O.fragilissima, O. hydnoides, O. stenodon, and O. brinkmanni. 6. The following species produced basidia and basidiospores in culture: O. fusco-atra, O. uda, O. arguta, O. hydnoides, and O. steno-don. 7. Only two species, O. arguta and O. stenodon, produced fructifications similar to those produced in nature. Cystidia, an important diagnostic character, were not formed in culture. 8. The following seven species proved to be homothallic, mycelium from single spores developing clamp connections and producing basidiospores: O. fusco-atra, O. uda, O. arguta, O. fragilissima, O. hydnoides, and O. stenodon. 9. O. bicolor and O. separans proved to be heterothallic, the mycelium from monosporous cultures lacking clamp connections which were formed only when two compatible strains were mated.