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The hydrophilous plant communities of Western Crete described and classified in this paper belong to the following classes: Potametea, Adiantetea, Phragmitetea, Molinio- Juncetea, Juncetea maritimi, Isoeto-Nanojuncetea and Alno-Populetea. Two new alliances and five new associations are described: Brachypodio-Holoschoenion, Dorycnio- Rumicion conqlomeratae. Dorycnio-Caricetum otrubae, Dorycnio-Cladietum marisci and Caricetum creticae (all Molinio-Juncetea), Acrocladio-Adiantetum (Adiantetea), and Juncetum subulato-maritimi (Juncetea maritimi).

As an extension of De Wit's competition theory a theoretical description has been developed of competition between plant populations with different rooting depths. This model shows that in mixtures of plants with different rooting depths the value of the Relative Yield Total can be expected to exceed one. Moreover, it predicts the frequency-dependence of the relative crowding coefficient of the deep rooting population with respect to the shallow rooting population. The relationship between properties of plant species and the environment required to establish a stable equilibrium turns out to be surprisingly simple. The shallow rooting species has to have a larger competitive ability sufficient to compensate for the extra nutrients that are exploited by the deeper rooting plants. The dependence of equilibrium plant frequencies on the properties of plant species and the characteristics of the environment is discussed.

In recent years pollen analysis has turned increasingly from historical plant geography towards paleoecology. More and more the main interest lies in a reconstruction of the past vegetation instead of simply floristics of a region. Vegetation as a rule is made up of communities¹) that can be described quantitatively in terms of species composition or qualitatively in terms of structure.

The vegetation was studied of a number of savannas in northern and southern Surinam, and in French Guiana. The results are compared in particular with the vegetation classification proposed earlier for northern Surinam, and with some records from the northern Rupununi Savanna, Guyana (Van Donselaar 1965). The savannas studied near Brownsweg (northern Surinam) have vegetation types that correspond completely with those of some other savannas of the same geological-pedological type more to the North, as described before. New is the finding of a type of scrub bordering the savanna, being the scrub equivalent of a type of bushes described earlier as the Marlierea type. On the top and the slopes of the Blauwe Berg near Berg en Dal (northern Surinam) an anthropogenic savanna has developed. Two new vegetation types are recorded here that belong to the alliance Rhynchosporo-Trachypogonion. At the foot of the hill a flat savanna supports a vegetation that gives the impression of being of recent origin and unbalanced. It appears possible to apply the existing classification to the communities found on savannas near Cayenne (French Guiana). In this area the conspicuous Byrsonima verbascifolia (var. villosa fo. spathulata) occurs in several undescribed vegetation types that belong to various entities. A xerophilous and a hygrophilous community of Byrsonima verbascifolia are distinguished, belonging to the Rhynchosporo-Trachypogonion and the Bulbostylidion lanatae, respectively. On the Sipaliwini Savanna in southern Surinam most vegetation types do not fit into one of the existing alliances. However, if new alliances would be described, it should be possible to include them into the existing orders. There probably is an alliance, called here “communities of Trachypogon plumosus and Bulbostylis spadicea”, that might be regarded as the southern counterpart of the Rhynchosporo-Trachypogonion in the order Trachypogonetalia plumosi, and a supposed alliance with much Rhynchospora graminea and R. globosa might have the same position with regard to the Imperato-Mesosetion in the order Paspaletalia pulchelli. Among the communities that might be included in the alliance Axonopodion chrysitidis there is one occurring on sandy soil without a hog-wallow structure at the surface. Floristically it has connections with the Paspaletalia pulchelli but it also has many characteristic species of its own. Whether this community has to be placed in a distinct alliance will have to depend on the results of further investigations in this area. Anyhow, more data are needed for the drafting of a complete picture of the rich and interesting Sipaliwini Savanna. On a savanna south-west of the airstrip “Sipaliwini” (southern Surinam) the vegetation consists mainly of communities belonging to the Bulbostylidion lanatae. Summarizing the above-mentioned results, one may say that a number of communities not studied before are added to the picture of the savanna vegetation of the Guianas. It proved possible to integrate these communities without much difficulty in the classification presented earlier that so far has functioned as a practical framework.

Daltonia fenestrellata Griffin was collected by A. M. Cleef in the Andes of Colombia in 1973. It is characterized by the cuspidate, incurved or recurved leaf tips, the elongated juxtacostal cells and the apically scabrous seta. It seems most closely allied to D. gomezii Crosby of Costa Rica.

For several years, The New York Botanical Garden has conducted a study of vegetation overlying certain ferruginous areas principally in Venezuela. During the winter of 1954-55, field work was organized to continue reconnaissance of plant-cover growing on iron-cap or ore-bodies in northeastern Brazil, French Guiana, Suriname, and British Guiana. In addition to studies in iron-bearing localities, observations and some statistical studies were made on manganiferous and bauxitic deposits in the region of Guiana. Dr. Cowan spent the period October-March in the field. We were together for the first three weeks, and again in the fore-part of January. Dr. Jan C. Lindeman of Utrecht accompanied Dr. Cowan for two weeks to Nassau-gebergte in Suriname. Independently I visited Nassau Mountains and Moengo for three weeks in March.

A few years ago a new and interesting mammal, which is exceedingly rare, even in its native haunts, was brought to the then Resident of Palembang, Mr. A. Pruys van der Hoeven. This gentleman who is not only an eager sportsman, but also well-versed in natural history, recognised it to be new to science and to be more closely allied to certain representatives of the Edentata, than to any other order of mammals. — The type-specimen was held in captivity for several weeks, was fed on ants and afterwards on cooked rice and was sent alive to Europe in order to be examined, described and ultimately preserved in the Royal Museum at Leyden. It unfortunately died on board the vessel, on its way to Holland, and by an unaccountable blunder on the part of one of those in charge, its remains were not preserved, but thrown overboard. During my own stay in Sumatra from February till May 1891 I took particular trouble to obtain further information concerning this animal and have found the fact of its existence — though at the same time of its exceeding rarity! — confirmed in a way which does not allow me to doubt that ere long further specimens will be available for a thorough examination, also with respect to anatomical detail. My own attempts to secure a second specimen have as yet not been successful, but as they have turned the attention of many persons towards this animal I feel bound, in deference to the claims to priority of its original discoverer, who has put his preliminary description as well as sketches of the animal at my disposal, to introduce this peculiar mammal into science, notwithstanding the type-specimen has been lost. The generic name has been selected, not with a view of indicating any closer anatomical relation with the genus Manis, but only to indicate that a hairy anteater is meant.