Browsing by Author "Verdcourt, B."
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Item A Contribution to the Mollusc fauna of Northern Somaliland(1963) Verdcourt, B.An account of the land molluscs of the area formerly known as Somaliland Protectorate, but now termed Somali Republic: (Northern Region), was given by CONNOLLY (1931). A recent journey by Mr. C. F. HEMMING, in September 1960, has so added to our knowledge of a part of this territory that I have considered it useful to write up his collection as a whole. The object of Mr. HEMMING's journey was a general ecological study, and molluscs were collected only incidentally; this survey will ultimately be published. No apology is made for mentioning a number of undetermined species since it focusses the attention of other workers on the presence of such material in I certain museums. Where spirit material ls available the number has been marked with an asterisk.Item East African Slugs of the Family Urocyclidae(1960) Polhill, R.; Verdcourt, B.In tropical regions the problems of specific differentiation are often much more difficult than, for example, in Britain; this is not merely due to the great difference in the amount of work which has been carried out in the latter country. Species do appear to grade into each other in some tropical groups and the more material one examines the more confused does the situation become. When a little material is available from a small area one finds that several distinctive forms appear to be recognisable but when an abundance of material is available from a much wider area these distinctions often break down.Item Flora of Tropical East Africa(1953) Verdcourt, B.Herbs, shrubs or leafless parasites, rarely small trees, frequently twining or prostrate, less often erect. Leaves alternate, exstipulate, usually simple,entire or often lobed. Flowers usually bracteate, axillary or terminal, solitary or in various inflorescences, almost always regular, ermaphrodite save in a very few small genera. Sepals 4-5, imbricate, free or joined at the base, often accrescent. Corolla sympetalous, variable but often funnelshaped or salver-shaped, entire or 4--5-1obed, induplicate-valvate or contorted. Stamens (3-)4--5, inserted in the corolla-tube, alternating with the Jobes; pollen smooth or spinulose. Ovary superior, entire or 2-4-lobed, of 2-3 carpels, 1-4 (very rarely 3 or 5)-locular. Styles 1-2(-3), simple and terminal; stigmas 1-4, variously shaped. Fruit usually dry and capsular, rarely a berry or nut-like. Seeds 1-4 (rarely 6 or 10), with endosperm.Item The Names of the Morning Glories Cultivated and Naturalised in East Africa(1957) Verdcourt, B.; East African HerbariumThe following species of Morning Glory are cultivated in East Africa (using the names accepted by students of the Convolvulaceae at present): - Ipomoea tricolor Cav., I. conge5ta R. Br., I. purpurea (L.) Roth and I. hederacea Jacq. Another species which comes into the discussion is I. nil (L.) Roth. These species have long been badly misnamed in most herbaria but we are not concerned with that. The experts on the family interpret or interpreted these names in a given way and a recent perusal of the specimens in the Linnean Herbarium concerned with the three Linnean names, shows that these specimens at least are not in accordance with modern interpretations. It will be as well to set down the currently accepted interpretations with basic synonymy 1) before discussing the matter further. The name I. tricolor Cav. appears to be correctly interpreted although I have not seen the type. The species will be lettered and the letter used when the actual plant itself and not the name is meant.Item New Species of Adenia (Passifloraceae) From Eastern Africa(1964) Verdcourt, B.IN 1891, ENGLER described Adenia globosa from Hildebrandt 2858, stating that he considered it to be the most interesting species in the genus. Since then, the species has been collected many times. Recently other species have been collected which are closely related to globosa and, in the herbarium, so similar, if the specimens are poor, as they so frequently are, that they have gone down in lists as sp. near globosa or globosa forma in the field, however, the species are clearly very distinct.Item A New Species of Limeum from Somaliland(1961) Verdcourt, B.The genus Limeum L. (Aizoaceae) 'has, owing to the efforts of H. C. Friedrich, been reduced to a commendably tidy state but new species continue to be discovered, two very distinct ones having been described2,3 since the publication of the monograph. Yet another distinct new species has been collected in north-east tropical Africa. Working in Africa where no authentic material of L. pterocarpum (Gay) Heimerl was available, I tentatively assigned the plant described below to that species. Comparison with the abundant material of Gay's species preserved at Kew showed numerous differences and Mr. Jeffrey agrees with me that it is a new plant.Item Notes from the East African Herbarium: VI(1958) Verdcourt, B.; East African HerbariumThis robust climber has not been recorded from East Africa before. It may be an introduction from the Mascarenes but it might just possibly be native, though such a conspicuous plant could hardly be overlooked.Item Notes from the East African Herbarium: VII(1958) Verdcourt, B.; East African HerbariumNearly 100 species of this large genus are native to, or commonly naturalised in East Africa. Besides remarks concerning the nomenclature of many of these, information about species from other parts of Africa is included. I have already made some remarks about the difficult question of the division of the genus into sections. Mr. Bullock has since pointed out to me a serious omission in my remarks: I had overlooked a much earlier selection of Ipomoea pes-tigridis L. as the type species of Ipomoea, made by House in 1908.Item Notes from the East African Herbarium: XII(1961) Verdcourt, B.The account of the family Convolvulaceae for the 'Flora of Tropical East Africa' was practically finished in East Africa in 1958. Certain problems arose which were impossible to solve in Africa and completion was delayed. Whilst in England, I took the opportunity of working over all the East African material for a second time; this has meant the revision of several of my former opinions and, I regret, the changing of more names. A very large amount of fresh material becomes available every year and this naturally modifies one's views constantly.Item Notes on the Plant and Molluscan Ecology of a Saline Desert Area in Italian Somaliland including the description of a new species of Cleopatra (Mollusca)(1956) Hemming, C.F.; Verdcourt, B.In December 1954 heavy rains resulting in bad road conditions caused one of the authors (C. F. H.) to stay at Beles Cugani ill Southern Somalia, situated at 00° 16' N., 41° 43' E. and at an altitude of 36-51 m. The opportunity was taken to collect, specimens of all the plants and snails observed and since reports other than .mere lists of species arc scanty the results were considered worthy of record. One new species has had to be described.Item Notes on the Tropical African Canellaceae(1954) Verdcourt, B.; East African HerbariumIn the course of the preparation of the account of the family Canellaceae for the Flora of Tropical East Africa two new names were found necessary. These taxa are validly published here.Item Notes on tropical African dodders(1952) Verdcourt, B.My attention has been drawn to an article by Dr. Nattrass in this journal (1941, EA. Agriculture on the subject of Cuscula species in East Africa. The fact that the article contains many wrong names is in no way any fault of its author. The account of the genus in the Flora of Tropical Africa (1906, 4 (2), 202-6) is exceedingly poor and inaccurate, the keys given to the species being quite useless. Moreover, whilst working at Kew during the preparation of an account of the genus for the Biological Flora of the British Isles and for the Flora of Tropical East Africa, I found that nearly half of the specimens of Cuscula preserved at Kew were wrongly determined. Since the account of the genus for the new flora must await the completion of the Convolvulacea by some other worker, a task that may not be started for several years, these notes are being published to correct previous literature.Item Notes on Tropical African Dodders(1952) Verdcourt, B.; E.A.A.F.R.O.My attention has been drawn to an article by Dr. Nattrass in this journal (1941, E.A. Agric. J., 6, 187-8), on the subject of Cuscuta species in East Africa. The fact that the article contains many wrong names is in no way any fault of its author. The account of the genus in the Flora of Tropical Africa (1906, 4 (2), 202-6) is exceedingly poor and inaccurate, the keys given to the species being quite useless. Moreover, whilst working at Kew during the preparation of an account of the genus for the Biological Flora of the British Isles and for the Flora of Tropical East Africa, I found that nearly half of the specimens of Cuscuta preserved at Kew were wrongly determined. Since the account of the genus for the new flora must await the completion of the Convoivuiacea' by some other worker, a task that may not be started for several years, these notes are being published to correct previous literature.Item Possible Occurrence of Strains in Species of Schistosomes(1957) Verdcourt, B.; P.O. Box 5166, Nairobi, Kenya ColonyIn a recent paper Cridland1 has stated among his conclusions that there is no evidence for the occurrence of strains in human schistosomes and also that he had found that certain species of snail did not appear to act as carriers. For example, he states that Bulinus africanus ovoideus (Bgt.) Will not act as a carrier of Schistosoma haematobium in Uganda, on the evidence that he had not been able to infect it in the laboratory. In the Kitui area of Kenya Bulinus (Physopsis) africanus ovoideus (Bgt.) And B. (P.) Nasutus (von Marts.) Both occur in ponds, dams and streams. The latter snail is common also in the coastal regions of north-east Tanganyika and is, in my opinion, quite different from the snail occurring in the Great Lakes which Mandahl–Barth2 recorded as nasutus. He agrees with me that different sub-species are involved.Item R. Occurring in East Africa(1962) Verdcourt, B.The writer has for several years been working on a Check List of East African non-marine mollusca. It has become apparent that although any type of list would be of great value, indeed will be a necessity for future progress, it is not possible to write a check list in the correct meaning of the term. Every genus needs revision, which in turn often involves dissection of topotypic material. The material and workers are not available for this task and any list which appears will be of a very preliminary nature.Item Remarks on the Classification of the Rubiaceae(1959) Verdcourt, B.The family Rubiaceae is a very well-defined group and its members are readily recognised. The combination of simple opposite leaves and stipules is the most obvious diagnostic character. Only a very few genera are doubtfully placed and sometimes placed in other familiesItem Some Notes on Tropical African Conyolvulaceae(1958) Verdcourt, B.; East African Herbarium, Ainsworth Hill P.O Box 5166, Nairobi, Kenya.In the short paper above, certain aspects of the taxonomy of East African Convolvulaceae are discussed and the following are the chief results obtained. Eremosperma Chiov. is a synonym of Hewittia Wight et Arn, the full synonymy of Ipomoea rubens choisy is given, A discussion of the variation of Ipomoea hildebrandtii Vatke and I. argyrophylla Vatke is given, a discussion of the variation of Ipomoea hildebrandtii Vatke and I. argyrophylla Vatke is given, the following new taxa are described: Stictocardia tiliifolia (Desr.) Hallier f. subsp. macalusoi (Mattei) Verdcourt; Ipomoea tenuirostris Choisy subsp. hindeana (Rendle) Verdcourt; Ipomoea transvaalensis Meeuse subsp. orientalis Verdcourt; Ipomoea hildebrandtii Vatke subsp. megaensis Verdcourt; Ipomoea somalensis Verdcourt; Turbina perbella Verdcourt.Item Typification of the Subdivisions of Ipomoea L. (Convolvulaceae) With Particular Regard to the East African Species(1957) Verdcourt, B.Whilst preparing the account of the Convolvulaceae for the Flora of Tropical East Africa it became evident that several people had divided up the genus Ipomoea but that each had prepared new sets of infra generic names. The system mostly used at present is that of Hallier f. (1893) and it is a reliable one. Some of his names however need changing to conform to the rules of priority in nomenclature.
