Imágenes de páginas
PDF
EPUB

U. UNCIALIS Suhr. Robben Island, Boodle! Wenek! Table Bay, Dreye! dreschowy, Tyson! Cape Agulhas, Hohenack.! Cape, Areschoug, Phyc. extraeurop. exsicc. No. 59; Hohenack.! No. 153; Dickie! Reeve !

ENTEROMORPHA COMPRESSA Kütz. Table Bay, Ecklon! Sea Point, Tyson! Knysna, Krauss.

Geogr. Distr. General.

E. FLEXUOSA J. Ag. Cape, fide De Toni.
Geogr. Distr. Atlantic. Pacific. Baltic.

Mediterranean.

E. BULBOSA Kütz. Robben Island. Table Bay, Drege. Sea Point, Cape Point, Kalk Bay, Knysna, Boodle!

Geogr. Distr. Southern oceans.

E. LINZA J. Ag. Cape, Drege!

Geogr. Distr. N. Atlantic. Baltic. Mediterranean. W. Indies. Tasmania.

E. INTESTINALIS Link. Cape Agulhas, Hohenack.! Cape, Drege! Brand!

Geogr. Distr. Atlantic. Mediterranean. W. Indies.

E. CLATHRATA Roth. Mouth of Olifants River, Drege. Algoa Bay, Sutherland!

Geogr. Distr. N. Atlantic. North Sea. West Indies. Tasmania. New Zealand.

LETTERSTEDTIA INSIGNIS Aresch. Port Natal, fide Areschoug. PRINGSHEIMIA SCUTATA Rke. On Placophora Binderi J. Ag., an epiphyte on Codium tomentosum. Kei Mouth, Flanagan! Geogr. Distr. Baltic. Scotland.

CONFERVEÆ.

CHATOMORPHA CLAVATA Kütz. Table Bay, False Bay to Algoa, fide Areschoug. Cape Point, Boodle!

Bay, Harvey!

Geogr. Distr. West Indies.

C. LINUM Kütz.

Geogr. Distr.

Atlantic.

Red Sea.

Sea Point, Boodle!

Port Natal, Krauss.

North Sea. Baltic.

Table

Mediterranean. North

C. NATALENSIS Hering. Port Natal, Krauss.

C. CRASSA Kütz. Kei Mouth, Flanagan!
Geogr. Distr. Adriatic. Ireland.

C. ÆREA Kütz. Kalk Bay, Boodle!

Geogr. Distr. Mediterranean, Atlantic shores of Europe, Canaries, United States, W. Indies, Australia.

RHIZOCLONIUM RIPARIUM Harv. Knysna, Krauss.

Geogr. Distr. North Sea. Baltic. Adriatic. Atlantic. Indian Ocean.

R. ARENOSUM Kütz. Cape, Hb. Dickie!

Geogr. Distr. British shores. Arctic ocean.

R. TORTUOSUM Kütz. Knysna, Boodle!
Geogr. Distr. North Sea.

CLADOPHORA NUDA Kütz. Cape Agulhas, Hohenack.! Meeralgen, No. 464. This specimen is so fragmentary that it is quite impossible to examine it satisfactorily, and I therefore take Hohenacker's naming on trust.

Geogr. Distr. Atlantic.

C. MEDITERRANEA Kütz. Cape Agulhas, Hohenack.! Meeralgen, No. 466.

Geogr. Distr. Mediterranean.

C. SPINULOSA Kütz.

No. 351.

Cape Agulhas, Hohenack.! Meeralgen,

Geogr. Distr. Mediterranean.

C. GLOMERATA Kütz. Port Natal, Krauss.
Geogr. Distr. General.

C. AFRA Kütz. Knysna, Krauss.

Geogr. Distr. Mauritius.

C. HOSPITA Kütz. Robben Island, Tyson! Table Bay, Ecklon, Harvey! Green Point, Harvey! Cape Point, Boodle! Cape Agulhas, Hohenack.! Knysna, Krauss. Cape, Gaudichaud, Drege! Areschoug, Phyc. extraeurop. exsicc. No. 60; Hb. Dickie! Harvey! Hb. Lenormand! Hb. Wenek! Reeve! Hohenack.! Meeralgen, Nos. 53, 204.

C. CATENIFERA Kütz. Table Bay, Harvey! Boodle! Kalk Bay, Boodle! Cape, Hb. Lenormand! Reliquiæ Brebissoniana! Ser. 2, No. 124.

C. FLAGELLIFORMIS Kütz. (? includes C. virgata Kütz.). Olifants River to Algoa Bay, Binder. Robben Island, Boodle! Table Bay, Drege! Krauss, Menzies! Harvey! Kalk Bay and Cape Point, Boodle! Knysna, Krauss. Cape, issued in Brebisson's Algues de France! Ser. 2, No.98; Hohenack! Meeralgen, No. 152; Hb. Wenek! C. RUPESTRIS Kütz. Cape, Brand! Harvey! Scott Elliot ! Geogr. Distr. Atlantic. Baltic.

C. TRICHOTOMA Kütz. Between Omsamculo and Omcomas, Drege. This is the only record of this alga from the Cape that I can find. In the Herbarium of the British Museum there is a specimen named "Conf. trichotoma, Cap. B. Spei. Herb. Roem.," which is clearly Cladophora hospita Kütz.; and as, with the exception of Mazé's Guadeloupe specimen, all other records of C. trichotoma are European, I am inclined to think that Drege's specimen was simply C. hospita Kütz.

Geogr. Distr. North Sea. Adriatic. W. Indies.

C. ECKLONI Kütz. Table Bay, Ecklon, Drege! Robben Island, Wenek! Cape Agulhas, Hohenack! Meeralgen, No. 463. Cape, Hb. Dickie Reeve Harvey!

Geogr. Distr. W. Indies.

C. VIRGATA Kütz. Table Bay, Binder.

C. CAPENSIS Ag.

Spec. dubia.

Cape, fide Areschoug (Phyc. cap. p. 13). ("Num Lychate Ecklonii?").

C. ACULEATA S. Algoa Bay, Ecklon.

C. RADIOSA S. Algoa Bay, mouth of Zwadtkap. Ecklon.

SIPHONEÆ.

MICRODICTYON UMBILICATUM Zanard. Port Natal, Krauss.

Geogr. Distr. Atlantic. Pacific. Mediterranean. Red Sea. APJOHNIA RUGULOSA G. Murr. Port Alfred, Carr! Kei Mouth, Flanagan! Algoa Bay, Becker! Cape, Harvey! Natal, Krauss! Sub nomine Confervæ prolifera Roth.

Geogr. Distr. Japan.

CHAMEDORIS ANNULATA Mont. Table Bay, fide Areschoug. Port Natal, Krauss !

Geogr. Distr.

Brazil. Indian Ocean. W. Indies.

(To be continued.)

SHORT NOTES.

ARCTIUM INTERMEDIUM IN WORCESTERSHIRE.

I met with one

plant of this species on the bank of the Severn, near the Ketch, between Worcester and Kempsey, on August 7th, 1890. So far as I can ascertain, it has not been recorded for this county before.— R. F. TOWNdrow.

[ocr errors]

HYBRID ORCHIS. I notice on p. 382 of last year's Journal that you would like to know whether I found more than one specimen of the natural hybrid Habenari-orchis viridi-maculata. I only found one specimen, which I removed at the time to what was formerly a wild garden at Longwitton, with the hope that it so might be preserved; I did not, however, see that it had come up last year, as I was not there at the right time. The spotted and frog orchises are both fairly abundant in the hay-field in which I found the hybrid, so that there must be plenty of opportunities for crossfertilisation, and it seems strange that it should not oftener occur. -CECIL H. SP. PERCIVAL.

VALERIANELLA CARINATA IN EAST KEnt. · My friend Mr. F. Smith sent me this plant a few months ago from Boughton Quarries, Linton, near Maidstone, where he has noticed it growing for several years. Atropa Belladonna occurs in the same quarries. Mr. Arthur Bennett has seen specimens.-ERNEST S. SALMON.

FESTUCA SYLVATICA Vill. IN Co. CORK. --During the summer of 1891, I found this handsome grass growing in a rocky wood overhanging the Glanmire estuary, about three miles east of Cork. Though this wood forms part of a private demesne, I think the plant has as much claim to be considered native as it has either near the Upper Lake, Killarney, or along the rocky bankside of the R. Feale, Listowel--all three localities being very similar. This is an addition to the Flora of Cork.-R. W. SCULLY.

NOTICES OF BOOKS.

Fossil Plants as Tests of Climate: the year 1892. By A. C. C. J. Clay & Sons. 1892. In this Essay Mr. Seward has undertaken the examination of a large and important question, and if his conclusions are less definite than could be wished, it is due rather to the state of existing knowledge than to a want of industry on his part. The subject being a wide one, he has restricted himself in the main to the task of bringing together such botanical and geological facts as are at present available for its discussion, and of calling attention to the several points of view from which previous writers have considered the subject. This will explain to the reader why the author has indulged so largely in quotation, and why, independent criticism, though not entirely absent, is not a prominent feature of the essay.

being the Sedgwick Prize Essay for SEWARD, M.A., F.G.S. London: 8vo, pp. xii. 151. Price 5s.

In a somewhat lengthy historical sketch, Mr. Seward traces the growth of such theories or opinions as have been formulated with regard to the connection between fossil plants and climatic changes in the past history of the earth. This is followed by brief accounts of plant distribution, and the life of plants at low temperatures, with special reference to Arctic vegetation. We then come to what we regard as one of the most important chapters in the whole essay, viz., that on "the influence of external conditions upon the macroscopic and microscopic structures of plants." Everyone allows that if plants are to be used as tests of climate in all possible ways, we ought to know to what extent it is possible to infer climatic conditions from morphological and histological details. Unfortunately, however, in spite of all that has been done in the way of distinguishing the floras of different climates in these respects, we are still far from such definite and constant relations between structure and climate as will enable us to pass with confidence from one to the other. The facts as they stand are fairly well summarised by the author, but they show most clearly that much experimental research will be required before we can use plant-structure as a guide to climate. In dealing with this part of his subject, Mr. Seward takes up one or two positions which we think will hardly be accepted by modern botanists. At the opening of the chapter it is stated that "plants with woody stems are able to live through the winter of the cold temperate zones, because the lignification of part of the plant tissues is followed by a development of cork, a screen against cold." italics are ours. Here he appears to have mistaken a condition for a cause, and to take a view of the function of cork not held by plant physiologists generally. A few sentences further on, reference is made to the woody plants of the tropics, and we read that "there, the wood is not a safeguard against the influence of cold, but serves to give the plants that firmness which they require to enable them to support their branches. In a tropical climate, cork must be looked upon, not as a screen from cold (italics ours), but as

The

a regulator of transpiration, of which it prevents excess." We venture to think that this statement is as correct for cold temperate plants as for tropical ones, and that neither wood nor cork is a special adaptation against cold.

In dealing with the possibility of using the structure of fossil plants as a guide to climate, the author gives most attention to those of the Carboniferous Period, and concludes that “we cannot as yet learn many lessons in Climatology from the structure of stems, roots, and other parts of fossil plants," In this we fully agree. Thanks to the researches of Carruthers, Williamson, and their continental co-workers, the minute structure of some of the best known types has been worked out with considerable detail, but this merely gives us some idea of the nature of the habitat, and throws little light on that of climate. In considering the case of Lepidodendron, Mr. Seward follows what is a common practice, and speaks of the vascular tissue as "wood." We would suggest that the time has arrived when a reform of this terminology is urgently needed, especially if we are to employ the structure of the fossil in the diagnosis of climate. As applied to Dicotyledons, the term "wood" represents neither a histological nor a physiological unity, but a mass of tracheids, fibres and cells, subserving the functions of conduction, mechanical support, and storage of elaborated food-stuffs. But in Lepidodendron, and several other Carboniferous plants, a corresponding complex of tissues is not met with. Here both the primary and secondary xylem are purely vascular, and contain no sclerenchymatous elements whatever, the mechanical function being performed by a zone of sclerenchyma which runs in the cortex near the periphery of the stem. Hence in these plants the term "wood" is as applicable to the mechanical as to the vascular tissue, but in either case does not mean the same thing as in Dicotyledons. If this were borne in mind we should not hear so much about the "comparatively feeble development of wood" in Lepidodendron, seeing that the mechanical tissue is often well developed, even in stems where the monostelic axis is unaccompanied by a zone of secondary xylem. Curiously enough, Mr. Seward describes this sclerenchyma as cork, overlooking the facts that it lies entirely within the generating layer, which produces it centrifugally, and that the tissues outside it appear to retain their power of growth even when it has attained considerable thickness.

Passing over the next two chapters on "Annual Rings in Recent and Fossil Plants" and "Arctic Fossil Plants" respectively, we have another excellent chapter on the Climate of the Carboniferous Period as indicated by other characteristics of the vegetation than those of structure. Here the evidence which has rendered untenable the old ideas of a tropical climate, with an atmosphere laden with moisture and carbon dioxide, is well set out, and special prominence is given to the views of the late Dr. Neumayer, of Vienna. There is nothing, however, which calls for special comment or criticism, and the same may be said of the closing chapter on the plants of the Pleiocene. THOMAS HICK.

« AnteriorContinuar »