A brief description has been given in an earlier paper (Goodey, 1943) of damage to tulip bulbs caused by the stem and bulb eelworm, Anguillulina dipsaci. In April, 1944, an opportunity arose, through the good offices of Mr. J. Oldnall Page, of Spalding, Lincs., of visiting a field in his district, in which eelworm-affected tulips were growing. Two of the varieties inspected were in flower and the other two were in an advanced bud condition. All four varieties exhibited marked symptoms of attack, and in the case of two of them in which there were a considerable number of plants, the damage caused to the blooms would entail a distinct financial loss to the grower. The largest planting consisted of the variety “ Rijnland,” the next largest was the variety “Wonderful.” In addition to these there were smaller plantings of “ William Copland ” and “ Mrs. Farncombe Sanders.” In all four varieties evidences of attack were apparent on leaves, stems and flowers and, in general, the writer can confirm the findings of Chitwood and Machmer (1942) on the symptoms manifested by the growing plant. They mention longitudinal splitting of leaf, flower-stem and corolla. It may be well, however, to attempt a more detailed description of the chief symptoms and types of lesion shown by affected plants: see also the two photographs accompanying this paper.

Further investigations on the occurrence of Anguillulina dipsaci on onion seed are presented. It is shown by the examination of 2,000 seeds individually that the parasite is usually located on the seed in the region of the hilum. A given seed may have as many as 4·7 worms or only 1 worm attached to it.

A method of seed fumigation with methyl bromide is described whereby the parasites attached to seeds are killed but the seed is unharmed. By the use of a test-bottle technique it has been found that a minimum dosage of 600, i.e. a concentration-time product of 600 involving an exposure to the fumigant of 18 to 24 hours at 24°C. is necessary for the destruction of the parasites attached to the seeds and in such flower-part débris as may be mixed with it.

The fumigant has no harmful effect on the vitality of the seed at dosages sufficient to destroy the parasite nor at much higher dosages. There is thus a wide upper margin of safety in its use. Two practical methods for the fumigation of large quantities of seed are described.

The probable origin of seed-borne infection from lightly infected parent bulbs is discussed. It is shown that at the present time seedborne infection is fairly widespread and has been found to occur on at least 9 different varieties of onion seed as distributed by seed merchants. Recommendations as to control are made which it is suggested would go far to reduce the incidence of the disease in this country.

In a recent paper the writer (Goodey, 1943) has shown that the stem eelworm, Anguilulina dipsaci, occurred in considerable numbers in the scape, i.e. the flower stem, and the inflorescence of onions grown for seed in Sussex during 1943. The worms, mainly consisting of infective larvae, occurred in the dry papery tissues lining the hollow scape, in the pedicels of the flowers and in various of the floral organs, such as withered sepals and petals, in the receptacle and placenta and on the walls of the seed capsule. They were also attached to the outside of the ripened seed. In a second paper (Goodey, 1945) it is further shown that the parasite becomes firmly attached to the seed chiefly in the region of the hilum, whence it cannot be removed by the usual processes of winnowing and cleaning. The foregoing results were obtained from plant material in a dry condition and seed samples which had been threshed and cleaned. Study of this material had made it evident that the parasite must somehow gain access to the living tissues of the scape and inflorescence as these grow from the parent bulb, but it was not apparent how this came about; whether from lightly infected parent bulbs or direct from the soil. Circumstantial evidence had been adduced in the two papers, already mentioned, pointing to lightly infected parent bulbs being the probable source of infection, but the whole matter needed further investigation to elucidate this and other points. In the present communication the results of studies directed to the solution of these questions are given.

In a recent paper the writer (Goodey, 1943) dealt with the systematic position of the vinegar eelworm and certain related species. A new subfamily, Turbatricinae, was erected and a new genus, Turbator, proposed for 7 species possessing morphological features differentiating them from the vinegar eelworm, Turbatrix aceti (Müller, 1873) v. aceti Peters, 1927. In regard to this paper, Dr. Gerald Thorne has sent a letter to the writer in which he has been kind enough to draw attention to two points which, in his view, call for emendation and correction, as follows.

Heterodera cruciferae n. sp., parasitic upon Brassicas and other Cruciferous plants, is described and compared with H. schachtii, the sugar beet eelworm.

The new species differs from the sugar beet eelworm in its host range, in the reaction of the larvae to root excretions of sugar beet and in the time of hatching of the larvae. The cysts are somewhat shorter and rounder than in the sugar beet eelworm and differ in having attached to the vulva a mass of jelly-like substance containing eggs and sometimes one or two males. The larvae are shorter than in H. schachtii. The males are similar but tend to be smaller and with shorter stylets.

The results of infection experiments with cysts from the roots of dock and of clovers indicate that these cysts are of the same race, and are probably a biological strain of the sugar beet eelworm H. schachtii.

The identification of the species of the genus Trichuris has been much simplified since the appearance of a paper by Chandler in 1930 in which he pointed out that the prepuce-like expansion surrounding the extruded spicule has very little diagnostic value because of its extreme variability. The length and appearance of the spicule is useful only when used in conjunction with other characters for this is a variable structure. However, the six species with which he was concerned could readily be distinguished by certain internal structures which seem to exhibit great constancy and reliability. These structures are the length of the cloacal tube and its diverticulum for the head of the spicule, the length and shape of the ejaculatory duct and the nature of the folding of the vas dcferens and of the testis. Using these characters and other minor ones, he was able to give useful descriptions of the males of Trichuris trichiura, T. vulpis, T. ovis, T. minuta and T. leporis and to describe a new species T. tenuis.

The material described consists of two small collections. One composed mainly of helminths from birds, was collected by Major T. A. Cockburn, M.D., D.P.H., on the Gold Coast in 1943. The other was collected from mammals by Dr. K. Morris, of the medical department, Kumasi, in 1939. To both of these collectors and to Dr. R. T. Leiper, C.M.G., F.R.S., who kindly put the material at my disposal, I am much indebted.

The bird material contained 8 different genera, of which one is a tremtftode, three are cestodes and the others are nematodes. The Acanthocephala are not represented.

A Squacco Heron, Ardeola ralloides, yielded a number of specimens of the trematode Clinostomum complanatum (Rud., 1814), Braun, 1899. They were taken from the oesophagus where they were actively moving about at the post-mortem examination. It is a small worm between 3 and 4 mm. long, strongly muscular with comparatively large suckers. The vitellaria are abundant and so deeply staining as somewhat to obscure the other organs. It has previously been recorded as a parasite of Ardea cinerea and Nycticorax griseus in Europe, but apparently both this host and this geographical distribution are new records. The vector is a fish; Ciurea in 1911 having implicated Perca fluviatilis.

The material on which this article is based was sent to Dr. R. T. Leiper, C.M.G., F.R.S., by Mr. L. R. Hutson, Veterinary Officer, Antigua, to both of whom my thanks are due. Most of the cestodes had already been described by Prof. J. G. Baer and recorded by him in 1940. The rest of the collection consists mainly of nematodes but there are, however, representatives of all three groups of helminths—Trematoda, Cestoda and Acanthocephala as well as the Nematoda. The hosts were all described by the local popular names and I am much indebted to Mr. Kinnear, of the Natural History Museum, London, for identifying them.

The only trematode in the collection is the Strigeid, Apharyngostrigca cornu Goeze, 1800, which had been removed from the large gut of a Yellow crowned night heron, Nycticorax violaceous. It has already been recorded from a number of birds belonging to the Ciconidae and to the Ardeidae but not from this particular host. It is not uncommon in Europe and the United States but has not been reported in the British West Indies before. There are two specimens both attached to the mucous membrane but they were easily removed and seemed to have caused no pathological changes. They are mature and contain eggs and the vitellaria are strongly developed, obscuring most of the other organs.

In the following article is described an interesting parasitic condition which is difficult to interpret. The small intestine of an Hadada, Geronticus hagedash, was brought back from the West Coast of Africa by Major T. A. Cockburn, M.D., R.A.M.C, who kindly passed it to me for further examination. The bird is a member of the family Plataleidae, living in wooded districts in West Africa in the neighbourhood of water and feeding on invertebrates, mainly annelids and small crustaceans which it finds at the bottom of ponds and streams in the mud.

Many crops of carrots grown in gardens and on a field scale, during the War, have been infested with a weed which bears a resemblance to Solanum nigrum. It has been identified as Solanum sarachoides Sendtner. The plant is a native of Temperate and Sub-temperate South America. The carrot seeds containing this impurity are said to be of Californian origin.

The plant possesses oval leaves, slightly more wavy than those of British specimens of S. nigrum. They are smooth and dark green in colour, but the stems are covered with short hairs. The habit is procumbent to prostrate and the weed creeps extensively through the dense foliage of the carrot crop. The inflorescences are borne laterally and display minute white flowers. Dark green berries are produced in great profusion each containing about 25 seeds. There is evidence that the plant is becoming established on light soils, in the market gardening districts of Staffordshire, and it is doubtless localised elsewhere.

It was noted that where the weed was growing adjacent to plots of potatoes affected with blight (Phytophthora infestans), that its leaves were also attacked. The lesions resembled those of potato blight and the identity of the fungus was confirmed by Mr. N. C. Preston, of Harper Adams Agricultural College.

Up to the present time, so far as the writer is aware, there has been no previous British record of galls on a moss caused by a nematode although cecidologists have reported galls of nematode origin on 52 species of moss on the continent of Europe (see Goodey, 1940). Except in the case of Hypnum cupressiforme L. and Thuidium delicatulum (L.) Hedw., in which the causal parasite is Anguillulina askenasyi (Bütschli, 1873), the specific identity of the worms affecting the other 50 species has not been determined though it is probable that in all cases they belong to the genus Anguillulina.