Page:The Botany of the Antarctic Voyage.djvu/199

Campbell's Islands.] Hypogena, nigra, maculam nigrani subeffusam superne stromatis indicern exhibens, una tanturn niacula in singulo folio ut videtur evoluta. Stroma -§—1 lin. latum, hemisphericmn, carbonaceurn, extus scabriusculum, neo evidenter papillato-granulosum, demum fatiscens: intus carbonaceum, superne reticulatim cellulosum, sub lente atro-caeruleum vel demum viridi-fuscum constans, basi in floccos abeunte. CeUulte fructifem oblongo-eUiptica>, periphericse, obtusi- usculae, vix apiculatse. Asci breviusculi. Sporidia octona, oblonga, uniseptata, medio constricta.

This species has much more the habit of a Spkaria than most Dothidea, being of a carbonaceous texture, like the Spharia fragiformis ; but though, on making a delicate vertical section, a thin stratum of tissue, consisting of only a single layer of cells, occasionally appears, no trace of this is seen on the sides of the cavities distinct from the neighbouring tissue. The specimens procured are not numerous, in no instance does more than one individual appear upon a single leaf, the latter being probably of too small a size to support more than a solitary stroma of such high organization. Like some other species indicated by Montague in his ' Fungi of Cuba,' this is probably originally produced between the layers of the cuticle, for some of the latter is found beneath the stroma. The cells of the stroma pass at the base into a mass of reticulated filaments, without any membrane being attached to the meshes.

Plate LXVII. Fig. II. — 1, a sprig of Veronica odora, with the fungus of the natural size ; 2, a section of the fungus; 3, a portion of the same, more highly magnified; 4, an ascus; 5, sporidia; 6, a section shewing the loose cellular tissue of the centre, the pentagonal tissue about the base of the cells, and the elongated tissue between them: — all magnified.

2. Dothidea spilomea, Berk.; gregaria, kypophylla, maculis epipliyllis nullis v. obsoletissimis, subinnata, depressa, tenuis, orbicularis, ssepe confluens, minutissime granulosa, nitida, cellulis globosis, ascis clavatis, sporidiis oblongis uniseptatis medio constrictis. (Tab. LXYII. Kg. I.)

Hab. Lord Auckland's group and Campbell's Island ; on the leaves of Veronica elliptica, Forst.

Hypogena, nigra, nitida ; maculis - lin. latis, gregariis, orbicularibus, quandoque confluentibus, depressis, subinnatis, tenuibus, minutissime granulatis. Stroma tenue, subtus cum parenchymate confusum. Cellulee fructifem globosae, ostiolo punetiformi. Asci clavati. Sporidia oblonga, quandoque curvata, uniseptata, medio constricta.

In some leaves the spots are very numerous, in others they are but few and of a larger size. The species is most allied to the D. amphimelana, Mont., and D. ZoUingeri, B. and M., although not very near either ; it exhibits, also, some affinity with D. granulosa, Hook, et Am. Externally it strongly resembles the punctiform variety of Rhytisma salicinum. The spots are of a shining black, and are very minutely granulated under a lens.

Plate LXVII. Fig. I. — 1, a sprig of Veronica elliptica, covered with the parasite, of the natural size; 2, a section, slightly magnified; 3, ditto, more highly magnified; 4, asci; 5, sporidia : magnified.

7. ASTEKOMA, Dec.

1. Asteroma dilatatum, Berk.; superficiale, maculis iccia^formibus, lobis dilatatis e filamentis serpentibus approximatis in membranam-congestis. (Tab. LXVIII. Fig. VII.)