Vaccinium Species Research Articles

A Note on the Genus Themistoclesia KL.

In reconsidering three species of Vaccinium proposed by the first author in 1933 (V. Benthamianum, V. anfractum, and V. Pen~tellii), we found it necessary to t ransfer these species to Themistoclesia. In making these transfers we were anticipated by Sleumer 1 who published a short discussion of this interesting genus and a key to the species recognized by him. As originally treated by the first author, 2 Themistoclesia contained six species. This number has now been increased to twelve, although we disagree with Slemner to the extent of again separating T. pendula and T. depertde~s, and of reducing T. Pittieri to T. mucronata. I t does not seem advisable to publish still another key to the species, as Sleumer's may be used. All the species have been adequately described in l i terature during the past few years. Eight species of the twelve appear elosely related, but the remaining four are very distinct, both from the first eight and from each other. Thus five species groups are readily recognizable in the genus. I t is even a debatable question whether the last four species should be left in Themistoclesia in the sense of T. penchda, the type species. The f ru i t of T. Dryanderae, for instance, appears to be a fleshy berry, and this character would remove it from the genus as it has been understood. A reconsideration of the genus is doubtless desirable, but for the present we limit ourselves to an outline of the five species groups and a discussion of the f ru i t character. SPEcms GRouP 1: pendulae. Calyx narrow at base, broad and flattened at apex; disk pubescent or glabrous; corolla short tubular,~ much narrowed at base; inflorescence up to 2 era. in length. Include~. T. hi~uta Smith, T. compacta Smith, T. peruviana Smith, T. vegasa~r Smith, T. pendula KI., T. dependens (Benth.) Smith, T. Pennelli:ii (Smith) Sleumer, and T. anfracta (Smith) Sleumer. Sleumer has expressed the opinion that T. pendula and T. dependens are identical, but we are unable to eonfirm this. In addition to slight and perhaps inconsequential differences in calyx proportions and position of the pedicellary braets, the species differ as follows: T. pendula: disk hir-sure; anthers rounded at base; T. dependens: disk glabrous; anthers;

TELIOSPORE DEVELOPMENT IN THE PUCCINIASTREAE

The genera that constitute the Pucciniastreae display a wide variation in the type of teliospore produced, as well as in the time and place of production. From the standpoint of development, however, there is a general situation that is common. In all genera primordial cells are formed from enlarged hyphal cells of the mycelium. These give rise to teliospore initials which are in the epidermal cells in Calyptospora, Milesia, Hyalopsora and Thecopsora, and are subepidermal in the other genera. These initials divide to form the mature teliospores, which are thick or thin walled, and few to many-celled. In all cases the teliospore is the product of a single primordial cell.The teliospores of Calyptospora goeppertiana are formed from a perennial mycelium, which causes a witches' broom and hypertrophied stems on species of Vaccinium. The mycelium gives rise to primordial cells in the cortex just below the epidermis. Each primordial cell pierces the host wall above and the contents pass in to form the initial, which by growth and division becomes the teliospore. The mature teliospores are one- to four-celled, with a thickened, dark brown wall. Development is not simultaneous, but progressive, and the teliospores are first formed in the basal parts, moving slowly upward until every cell of the hypertrophied portion of the stem is completely filled. In four species of Milesia the method of development is similar. The spores, however, are thin walled, and are formed in the epidermal cells of the overwintered fronds of their fern hosts. Thecopsora vacciniorum is similar to Milesia in many respects. The teliospores are intra-epidermal, thin walled and multicellular. In Pucciniastrum the teliospores are subepidermal, and arise from primordial cells, as in Calyptospora, Milesia and Thecopsora. The teliospore initials are closely packed, and the mature spores may form extended crusts. The simplest type of development is found in Uredinopsis, which is generally considered to be the most primitive of the fern rusts. Primordial cells are formed in the same way as in the other genera. These round up to form the initials, and cross walls are laid down to give the mature spores.From these studies two possible lines of development are suggested, both beginning with Uredinopsis. One line would lead through the intra-epidermal forms, as Milesia, Calyptospora, etc., and the other through the subepidermal genera, as Pucciniastrum and Melampsoridium.

On the Life History and the Poison Apparatus of the White Flannel Moth, Lagoa Crispata Packard.

The white flannel moth, according to Holland, ranges from Massachusetts southward along the coast. According to Riley and Johannsen, the white flannel moth occurs in the Atlantic and Southern United States. The caterpillar, Holland says, feeds on blackberry. As early as 1869 the life history of this species was observed by J. A. Lintner. In the published account there are very complete descriptions of the various stages, of the habits of the larvae, as well as of the manner of spinning the cocoon. The number of larval instars observed were six. The host plants of the larvae are given as various species of Quercus, Vaccinium, Pteris aquilina, and other plants. According to Smith, quoted by Felt, the caterpillar,“lives on most of the orchard trees and small fruits as well as many other trees and shrubs.” Felt lists, in addition to the host plants named above, elm, apple, and raspberry.